Inhibitory effects of sword bean extract on alveolar bone resorption induced in rats by Porphyromonas gingivalis infection.

BACKGROUND: The domesticated legume, Canavalia gladiata (commonly called the sword bean), is known to contain canavanine. The fruit is used in Chinese and Japanese herbal medicine for treating the discharge of pus, but its pharmacological mechanisms are still unclear. OBJECTIVES: This study examined the effect of sword bean extract (SBE) on (i) oral bacteria and human oral epithelial cells in vitro, and (ii) the initiation and progression of experimental Porphyromonas gingivalis-induced alveolar bone resorption in rats. MATERIAL AND METHODS: A high-performance liquid chromatography/ultraviolet method was applied to quantitate canavanine in SBE. By assessing oral bacterial growth, we estimated the minimum inhibitory concentration and minimum bactericidal concentration of SBE, canavanine, chlorhexidine gluconate (CHX) solution. The cytotoxicity of SBE, canavanine, CHX, leupeptin and cystatin for KB cells was determined using a trypan blue assay. The effects of SBE, canavanine, leupeptin and cystatin on Arg-gingipain (Rgp) and Lys-gingipain (Kgp) were evaluated by colorimetric assay using synthetic substrates. To examine its effects on P. gingivalis-associated periodontal tissue breakdown, SBE was orally administered to P. gingivalis-infected rats. RESULT: Sword bean extract contained 6.4% canavanine. SBE and canavanine inhibited the growth of P. gingivalis and Fusobacterium nucleatum. The cytotoxicity of SBE, canavanine and cystatin on KB cells was significantly lower than that of CHX. Inhibition of Rgp with SBE was comparable to that with leupeptin, a known Rgp inhibitor, and inhibition of Kgp with SBE was significantly higher than that with leupeptin at 500 µg/mL ( p < 0.05). P. gingivalis-induced alveolar bone resorption was significantly suppressed by administration of SBE, with bone levels remaining comparable to non-infected animals ( p < 0.05). CONCLUSION: The present study suggests that SBE might be effective against P. gingivalis-associated alveolar bone resorption.

Preoperative estimation of remnant hepatic function using fusion images obtained by (99m)Tc-labelled galactosyl-human serum albumin liver scintigraphy and computed tomography.

BACKGROUND: Assessment of hepatic functional reserve is important in hepatic resection. The aim of this study was to evaluate the role of hepatic asialoglycoprotein receptor (ASGP-R) analysis in the preoperative estimation of remnant liver function in liver surgery. METHODS: One hundred and one patients undergoing hepatic resection for liver tumours were studied. Seventeen patients had preoperative percutaneous transhepatic portal vein embolization (PTPE). Function of the hepatic remnant was estimated before surgery using radioactivity in fusion images of both liver single-photon emission computed tomography and computed tomography scans using (99m)Tc-labelled diethylene triamine penta-acetate-galactosyl-human serum albumin. RESULTS: All three patients with an ASGP-R concentration below 400 nmol/l and preoperative total amount of receptor in the future remnant liver (R0-remnant) of less than 53.0 nmol per liver died. Two patients with chronic hepatitis and R0-remnant values between 53.0 and 65.0 nmol per liver and a receptor concentration lower than 600 nmol/l developed liver dysfunction. The incidence of liver failure decreased inversely with increasing R0-remnant value. CONCLUSION: A combination of receptor concentration and the amount of hepatic receptor in the future liver remnant as detected on fusion images is useful in evaluating the risk of postoperative liver failure.

Aberration of genomic DNA in association with human hepatocellular carcinomas detected by 2-dimensional gel analysis.

Alterations of genomic DNAs in primary hepatocellular carcinomas (HCCs) were examined by restriction landmark genomic scanning (I. Hatada et al., Proc. Natl. Acad. Sci. USA, 88: 9523-9527, 1991) which is a 2-dimensional gel analysis that allows detection of deletion, amplification, or other rearrangements of genomic DNA. Sixteen HCC samples together with their normal counterparts were tested in this manner. Each HCC sample was micromanipulated to minimize possible carryover from non-malignant cells. DNAs from HCCs and their normal counterparts were cleaved with the restriction enzyme NotI, end labeled with 32P, and size fractionated by 2-dimensional electrophoresis using HinfI as the second cleavage enzyme. The resulting spots (about 2000) in HCC samples were compared with their normal counterparts. Five spots were more intense in 10-14 of the 16 HCCs (63-88%). The intensity of several spots was reduced to about half, suggesting the loss of one of two alleles. Some of these decreases were observed frequently in different HCC samples, whereas others were sporadic. Sixty of these spots reproducibly decreased in > 2 cases, with 27 showing a decrease in > 50% of the informative cases. The highest incidence was observed in 14 of 16 samples (88%). No significant correlations were observed between these changes in spots and hepatitis B virus or hepatitis B virus infection. The use of landmarks that show a reproducible increase or decrease in intensity is discussed in conjunction with future studies of genomic alterations inherent in HCC.

Restriction fragment length polymorphism of bcr in Japanese patients with hematological malignancies.

We surveyed DNAs from patients with various hematological malignancies by Southern blot hybridization to analyze bcr rearrangements, and detected a new restriction fragment length polymorphism (RFLP) of the breakpoint cluster region at a BamHI site in three patients. By using a 1.2-kb HindIII-BglII 3' bcr probe, unusual BamHI restriction enzyme fragments (1.9 kb and 1.4 kb) were detected from the DNAs of three patients with hematological malignancies. DNAs from cultured fibroblasts derived from the skin of a patient, as well as from peripheral leukocytes of the father of a patient and the mother of another patient, showed identical 1.9- and 1.4-kb additional bands, besides a 3.3-kb germline band, establishing that polymorphism, rather than gene arrangement, was responsible for these additional restriction enzyme fragments. However, RFLP was not detected in the DNAs of 40 normal unrelated individuals.

CPP32/Yama/apopain cleaves the catalytic component of DNA-dependent protein kinase in the holoenzyme.

DNA-dependent protein kinase (DNA-PK) is composed of a 460-kDa catalytic component (p460) and a DNA-binding component Ku protein. Immunoblot analysis after treatment of Jurkat cells with anti-Fas antibody demonstrated the cleavage of p460 concomitantly with an increase in CPP32/Yama/apopain activity. Recombinant CPP32/Yama/apopain specifically cleaved p460 in the DNA-PK preparation that had been purified from Raji cells into 230- and 160-kDa polypeptides, the latter of which was detected in anti-Fas-treated Jurkat cells. The regulatory component Ku protein was not significantly affected by CPP32/Yama/apopain. DNA-PK activity was decreased with the disappearance of p460 in the incubation of DNA-PK with CPP32/Yama/apopain. These results suggest that the catalytic component of DNA-PK is one of the target proteins for CPP32/Yama/apopain in Fas-mediated apoptosis.

Prospective and randomized trial of lipiodol-transcatheter arterial chemoembolization for treatment of hepatocellular carcinoma: a comparison of epirubicin and doxorubicin (second cooperative study). The Cooperative Study Group for Liver Cancer Treatment of Japan.

A randomized, controlled clinical trial was conducted to compare the use of epirubicin (EPI) and doxorubicin (DOX) in Lipiodol (Laboratoire Guerbet, Roissy-Charles-de-Gaulle Cedex, France)-transcatheter arterial chemoembolization as a treatment of hepatocellular carcinoma. One hundred ninety-two hospitals participated, and 415 patients were enrolled in the study during the period between October 1989 and December 1990. The patients were randomly allocated to group A (EPI) or group B (DOX) by a centralized telephone registration. The actual doses of EPI and DOX were 72 mg/body and 48 mg/body, respectively. The 1-, 2-, and 3-year survival rates were, respectively, 69%, 44%, and 33% for group A and 73%, 54%, and 37% for group B. There were no statistically significant differences (P = .2296, log-rank test). When each group of patients was classified retrospectively into high-risk and low-risk subgroups based on the severity index calculated by the Cox regression model from the significant prognostic factors (the pretreatment tumor size, the pretreatment serum alpha-fetoprotein level, tumor encroachment, and Child's classification), the survival curve of the low-risk DOX subgroup was significantly superior to that of the low-risk EPI subgroup (P = .0182). However, there was no significant difference between the high-risk subgroups (P = .4606). The change in the serum alpha-fetoprotein level, the extent of Lipiodol accumulation in the tumor, and the extent of tumor reduction after the treatment did not show any significant differences between the groups. The white blood cell count in group B showed a tendency to decrease slightly more than in group A at 3 weeks after Lipiodol-transcatheter arterial chemoembolization. In conclusion, there was no statistically significant difference between the survival curves of the EPI and DOX groups in Lipiodol-transcatheter arterial embolization treatment of hepatocellular carcinoma.

Dephosphorylation of specific proteins in HL-60 cells by 1 alpha, 25-dihydroxyvitamin D3: possible involvement of cAMP-dependent protein kinase.

Changes of phosphoprotein patterns in HL-60 cells were studied during short exposures to 1 alpha, 25-dihydroxyvitamin D3 [1,25(OH)2D3]. One hundred nanometers 1,25(OH)2D3 dephosphorylated at least three proteins in 6 h: phosphoproteins with molecular weights of 82 kD (pp82), 33 kD (pp33), and 31 kD (pp31). Phosphorylation of pp33 and pp31 was also suppressed by 1 mM dbcAMP, and dephosphorylation of the two protein by 1,25(OH)2D3 was inhibited by 8 microM H-8, an inhibitor of cAMP-dependent protein kinase (PKA). Furthermore, 8 microM H-8 inhibited dephosphorylation of the two proteins when it was added with 1,25(OH)2D3. On the other hand, 10 nM TPA gave no significant change to these two phosphoproteins. These results suggest the possibility that PKA is involved in the early stages of 1,25(OH)2D3-induced HL-60 cell differentiation through specific protein dephosphorylation.

High mobility group proteins 1 and 2 can function as DNA-binding regulatory components for DNA-dependent protein kinase in vitro.

The DNA-dependent protein kinase (DNA-PK) holoenzyme consists of a 470-kDa catalytic subunit (DNA-PKcs), a DNA-binding regulatory component known as Ku protein, and double-stranded DNA (dsDNA) with ends. We previously reported that the activity of DNA-PK in vitro is stimulated by non-histone chromosomal high mobility group proteins (HMG) 1 and 2 comprising two similar repeats, termed domains A and B, and an acidic C-terminal. Here we demonstrate that in vitro HMG1 and 2 can completely replace Ku protein as the DNA-binding regulatory component of DNA-PK. DNA-PKcs and Ku protein were separately purified from Raji nuclear extracts, and reconstituted into the DNA-PK holoenzyme in the presence of dsDNA. DNA-PKcs alone catalyzed DNA-dependent phosphorylation at a very low but significant level, and HMG1 and 2 markedly stimulated the phosphorylation of alpha-casein and a specific peptide substrate in a DNA-dependent manner. The HMG2-domains (A+B) polypeptide devoid of the C-terminal acidic region was more effective for DNA-PKcs stimulation than the full-length HMG2, and HMG2-domain A and -domain B polypeptides. Anti(Ku protein) antibodies inhibited the DNA-dependent phosphorylation activity of the DNA-PKcs:Ku protein complex, but not that of DNA-PKcs alone or when it was complexed with HMG1 or 2. These results demonstrate that HMG1 and 2 can function as the DNA-binding regulatory component for DNA-PKcs in vitro, and imply that a conformational change of dsDNA, which is elicited by regulatory components, is important for the stimulation of DNA-PK activity of DNA-PKcs.

Effects of transcatheter arterial chemoembolization with oral chemotherapy on hepatic neoplasms.

An investigation was carried out into the effects of lipiodol-transcatheter arterial chemoembolization (L-TACE) therapy on hepatocellular carcinoma (HCC) and metastatic liver cancer, as well as the effects of oral 5-fluorouracil administration after L-TACE. For L-TACE, lipiodol mixed with adriamycin (doxorubicin) was injected through a catheter inserted into the tumor feeding artery and this was followed by embolization with a gelatin sponge. Twenty national hospitals throughout Japan participated in this multicenter co-operative open trial. A total of 102 patients became the subjects of study, including 75 HCC patients, 12 metastatic liver cancer patients treated with L-TACE, and 15 HCC patients who had hepatectomy after L-TACE. In 22% of the HCC patients and in 42% of the metastatic liver cancer patients, the tumor size was reduced by more than 50% after L-TACE. 73% of the 63 HCC patients showed a more than 50% reduction of the levels of serum alpha-fetoprotein. Although the survival rates of the HCC patients who had a hepatic resection were better than those who had not, there was no statistically significant difference between the survival rates of the HCC patients and those of the metastatic liver cancer patients treated with L-TACE. The survival rates of the HCC patients after L-TACE did not change as a result of oral 5-fluorouracil administration. It was therefore concluded that L-TACE is an effective way of treating both HCC patients and metastatic liver cancer patients, and that repeated L-TACE should be considered for some patients whose serum levels of alpha-fetoprotein rose again after L-TACE. Further follow-up studies will be needed to discover the effects of oral chemotherapy after L-TACE.

Treatment of hepatocellular carcinoma by transcatheter hepatic arterial injection of radioactive iodized oil solution.

After 12 days of culture, VX2 carcinoma cells were inoculated into the liver of 16 rabbits; 14 days later, 131I-labeled iodized oil ([131I]-Lp) suspended in lipiodol was injected into the hepatic artery. Selective accumulation of the contrast material in the tumor for an extended time was evident on X-rays and hepatic scintiphotographs. The antitumor effect was remarkable. [131I]-Lp agents warrant further examination for their clinical usefulness. Internal radiation therapy by transcatheter hepatic arterial injection of [131I]-Lp (group A) was evaluated in 9 patients with hepatocellular carcinoma (HCC, tumor stage III or IV) associated with liver cirrhosis (LC) and compared with combination therapy of Lp-TAE (group B) in 18 patients with HCC (tumor stage III or IV) associated with LC. In group A, serum AFP levels dropped rapidly in eight of the nine patients who had an elevated initial level of more than 500 ng/ml. The average reduction in tumor size was 50% in eight cases as determined by computed tomography. Histological examination of one resected liver specimen at 3 months after the third injection of [131I]-Lp revealed microscopic features highly suggestive of a radiation effect in the [131I]-Lp-containing area. The 1-year survival value for patients with HCC was estimated at 49.0% using the Kaplan-Meier method. The survival of patients treated with internal radiation therapy tended to be better than that of those treated with Lp-TAE (P = 0.119).

Estimation of remnant liver function before hepatectomy by means of technetium-99m-diethylenetriamine-pentaacetic acid galactosyl human albumin.

To improve the results of hepatectomy in cirrhotic patients, the likely reserve function of the liver was evaluated before surgery. Asialoglycoprotein receptor (ASGP-R) is a hepatic cell surface receptor specific for galactose-terminated glycoproteins. Technetium-99m-diethylene triamine pentaacetic acid-galactosyl human serum albumin (99mTc-GSA) is a newly developed analog ligand to ASPG-R. The probable functional reserve of the remnant liver after hepatectomy was estimated preoperatively as the hepatic binding protein (HBP) concentration specific for ASGP-R on the hepatocellular membrane of the remnant liver. This estimate was based on the effective liver volume rate, obtained by the uptake of 99mTc-GSA. In all, 3 normal volunteers, 3 patients with chronic hepatitis (CH), 9 patients with liver cirrhosis (LC), 2 patients with hepatic cystadenoma, 3 patients with hepatocellular carcinoma (HCC) associated with CH, and 21 HCC patients with LC were studied. The mean value +/- SD obtained for HBP in normal volunteers (three cases) and in patients with mild (four cases), moderate (two cases), and severe liver damage (five cases) were 0.74 +/- 0.03 microM, 0.43 +/- 0.042 microM, 0.31 +/- 0.05 microM, and 0.20 +/- 0.05 microM, respectively. Most of the cases in which the preoperative HBP of the remnant liver was above 0.22 microM had a good postoperative course irrespective of the type of hepatectomy. On the other hand, in subjects with a remnant liver HBP of between 0.22 and 0.11 microM, postoperative severe liver dysfunction occurred in about 50% of cases. In all cases with a remnant liver HBP below 0.1 microM, the prognosis was very poor, indicating that hepatectomy should be avoided. The HBP concentration detected by the 99mTc-GSA study is a very sensitive indicator of changes in the hepatic functional reserve, and the HBP value for the functional reserve of the remnant liver is extremely useful for estimating the liver function before and after hepatectomy.

Persistent primitive hypoglossal artery associated with Arnold-Chiari type I malformation.

The case of a 49-year-old woman with persistent primitive hypoglossal artery associated with Arnold-Chiari type I malformation is reported. The hypoglossal artery was located on the left side. The left vertebral artery was hypoplastic, the right vertebral artery could not be visualized angiographically. The clinical significance of a persistent primitive hypoglossal artery is discussed.

Point mutations in the S and pre-S2 genes observed in two hepatitis B virus carriers positive for antibody to hepatitis B surface antigen.

Two hepatitis B virus (HBV) carriers who had antibodies to HBV surface antigen (anti-HBs) were studied. Case 1 was a 47 year old woman positive for hepatitis B e antigen (HBeAg), and case 2 was a 61 year old man positive for antibody to HBeAg (anti-HBe) and DNA-polymerase (DNA-p). Neither case had received the HBV vaccine. The nucleotide sequences of the HBV-DNA extracted from the patients' sera were determined within the pre-S2 and S genes. Seven out of nine S gene clones from case 1 and six out of nine S gene clones from case 2 had an amino acid replacement from Thr or Ile to Ser at codon 126 in the alpha-determinant of the S gene. Amino acid substitution of codon 145 of the S gene previously reported was not observed. Although two previous reports on HBV escape mutant carriers with both anti-HBs and HBeAg described some deletions in the pre-S2 gene, our cases did not show these deletions. Our analysis indicated that carriers with the HBV escape mutant did not always have pre-S2 gene deletions. We found two HBV escape mutant carriers who had amino acid substitutions at codon 126 in the S gene due to point mutation without any deletions in the pre-S2 gene.

Expression of the midkine gene in human hepatocellular carcinomas.

BACKGROUND/AIMS: Aberrant expression of Midkine (MK) has been found in various human carcinomas including hepatocellular carcinoma (HCC). The aim of study is to identify the incidence of MK expression in tumor and surrounding non-tumor tissues of the liver, and to find the correlation of MK expression with other tumor markers. METHODOLOGY: Liver tissues were obtained from 16 patients with HCC and 4 with metastatic liver cancer. Background diseases of the HCC patients include liver cirrhosis and chronic hepatitis of type B or C. RNA was prepared from both cancerous and surrounding non-cancerous tissues, and analyzed for the presence of MK mRNA by RT-PCR, PCR-Southern blot, and Northern blot analysis. RESULTS: MK expression was detected in 12 (75%) of 16 HCCs by PCR-Southern blot analysis, the most sensitive of the 3 methods. Three of 9 surrounding cirrhotic tissues were weakly positive for MK expression, and none of chronic hepatitis and 4 normal tissues were negative. No significant difference was found in clinical and pathological parameters between MK negative and positive cases. Among metastatic cancers, 1 of gastric origin was positive for MK expression, but 1 each of chorangiocellular, gall bladder, and gastrinoma origin was negative. CONCLUSIONS: These results suggest that MK is expressed in the majority of HCC tissues and rarely in surrounding tissues in chronic liver diseases.

Reciprocal gene expression of rat fibroglycan and beta-actin during the course of regeneration after D-galactosamine liver injury.

BACKGROUND/AIMS: Fibroglycan (FG) is a major heparan sulfate proteoglycan (HSPG) in the rat liver that is mainly distributed on the surface of hepatocytes. HSPG may play some important roles in the regeneration of liver by interacting with various growth factors such as bFGF and HB-EGF. However, little is known about the function of FG. We reported that after injury caused by D-galactosamine, regeneration started on the following day and peaked on day 2. To clarify the function of FG in liver regeneration, we investigated the gene expression of FG during regeneration after D-galactosamine injury. MATERIALS AND METHODS: Rats were given D-galactosamine on day 0. Liver RNA was collected from day 0 to day 7. The gene expression of FG and beta-actin (as a representative cytoskeleton) was examined by Northern and/or Slot blotting. RESULTS: FG gene expression was markedly decreased on day 2, but totally recovered on day 3. In contrast, beta-actin gene expression was markedly increased on day 2 and returned to the normal level on day 3. Expression of the FG and beta-actin genes was reciprocal. CONCLUSION: FG expression is transiently suppressed when cytoskeleton gene expression is enhanced at the early phase of liver regeneration.

Promoter-independent loss of mRNA and protein of the Rb gene in a human hepatocellular carcinoma.

BACKGROUND: Inactivation of the retinoblastoma (Rb) gene is considered to play a fundamental role in the genesis and progression of several human cancers. In retinoblastoma, the inactivation of Rb promoter by mutations or hypermethylation has been reported. Although genetic changes of Rb gene have been described in hepatocellular carcinoma (HCC), an epigenetic change such as hypermethylation of the Rb promoter as reported in retinoblastoma has not been described. MATERIALS AND METHODS: We examined the hypermethylation in the promoter region of Rb gene by restriction fragment length polymorphism in 19 HCCs, as well as the expression of Rb mRNA and protein by RT-PCR and by immunoblotting, respectively. RESULTS: We found no evidence of hypermethylation in the promoter region of the Rb gene in all HCCs analyzed. However, the expression of Rb mRNA and protein was lost in one HCC, and no mutation was detected in the Rb promoter region of this patient. The inactivation of Rb promoter by hypermethylation or by inhibition of binding of transcription factors due to point mutations did not contribute to the loss of mRNA and protein in the patient. CONCLUSIONS: Hypermethylation in the Rb promoter region appeared to have little causal effect on HCC.

Determination of antibody to hepatitis B core antigen by radioimmunoassay in chronic liver disease.

Antibody to hepatitis B core antigen (anti-HBc) was measured by radioimmunoassay using CORAB (Abbott Laboratories) in 10 cases of chronic persistent hepatitis (CPH), 46 cases of chronic aggressive hepatitis (CAH), 33 cases of liver cirrhosis (LC) and 53 cases of hepatocellular carcinoma (HCC) in relation to hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs). Ninety-eight point four percent of patients with HBsAg and 93.8% of patients with anti-HBs were positive for anti-HBc and the titers of anti-HBc in patients with HBsAg were significantly higher than those with anti-HBs. Thirty-five point five percent of patients negative for either HBsAg or anti-HBs were positive for anti-HBc. The titers of anti-HBc in patients with CPH, CAH and LC were relatively low, whereas 7 (46.8%) of the HCC patients negative for either HBsAg or anti-HBc had high titers of anti-HBc. The significance of the presence of anti-HBc alone is discussed.

Serodiagnosis of type A hepatitis by detection of immunoglobulin M-type antibody to hepatitis A virus.

Serum specimens from 12 patients with type A hepatitis were analyzed for immunoglobulin M-type antibody to hepatitis A virus (IgM anti-HA). A recently developed solid-phase radioimmunoassay kit for IgM anti-HA (HAVAB-M, Abbott Laboratories) and a competitive binding radioimmunoassay kit (HAVAB, Abbott Laboratories) with or without 2-mercaptoethanol treatment, as modified by Yano et al. (Acta Hepatol. Jpn. 21, 704-712, 1980) were used to obtain an M-index. All specimens obtained within 60 days of the onset of illness and specimens from 2 of 4 patients later than 60 days after the onset were positive with the HAVAB-M test. This test gave negative results to sera which were positive for anti-HA by a standard HAVAB test in the following: 3 patients with type B hepatitis; 5 with non-A, non-B hepatitis; 11 healthy adults; and 10 sera strongly positive for rheumatoid factor. The M-index for type A hepatitis in sera within 30 days of the onset (mean value of the M-index, m, = 1.52; standard deviation, SD, = 0.25) was significantly higher than that for non-A hepatitis (m = 1.05; SD = 0.15) and for healthy adults (m = 1.02; SD = 0.10). The simplicity and usefulness of the HAVAB-M test in diagnosis of acute type A hepatitis over those measuring the M-index by HAVAB tests were shown by direct comparison of the results.

Detection by western blotting of an antibody to the hepatitis C virus E1 envelope protein in sera of patients with chronic liver disease.

We detected an antibody to HCV envelope protein (E1) in sera of patients with HCV-related chronic liver diseases (20 patients with chronic hepatitis and 5 patients with liver cirrhosis) by Western blotting using the fusion protein of E1 envelope protein and beta-galactosidase as an antigen. The antibody to HCV E1 (anti-HCV E1) was detected in 8 (42%) of 19 patients positive for HCV-RNA (16 were positive and 3 were negative for antibody to C100-3) and in 1 (17%) of 6 patients negative for HCV-RNA but positive for antibody to C100-3. HCV-RNA was detected in 8 (89%) of 9 anti-HCV E1 positive sera. The value of alanine aminotransferase was significantly higher in patients positive for anti-HCV E1 than in patients negative for the antibody. Although an antibody to the envelope protein of HCV is suspected to be one of the candidates of virus-neutralizing antibodies, our results suggest this hypothesis appears to be unlikely.

Experimental incineration of low level radioactive samples.

To determine the volume reduction potential for incineration of radioactivity in low-level radioactive waste, an incineration experiment was performed at the Okayama University Radioisotope Center (OURIC). Solid low-level radioactive samples (LLRS) were prepared for 15 routinely used radionuclides (45Ca, 1251, 32p, 33p, 35S, 59Fe, 123I, 131I, 67Ga, 99mTc, 111In, 3H, 14C, 51Cr, and 201Tl). For each radionuclide, incinerated one at a time, the smoke duct radioisotope concentration was less than 1/10 of the regulatory concentration limit (The Japanese law concerning prevention of radiation hazard due to radioisotopes, etc.). The radionuclide-containing combustible and semi-combustible LLRS were incinerated at the AP-1 50R furnace erected at OURIC, and the distribution of radioactivity inside and outside the furnace was measured. In the experimental incineration of LLRS containing these 15 radionuclides, the fractions released (RF) in the gas phase of the final smoke duct ranged from 0.165 to 0.99. The radioactivities remaining in the incineration residue were 99mTc, 87%; 59Fe, 83.1%; 45Ca, 75%; 51Cr, 62.1%; 33P, 62.0%; 32P, 61.1%; 67Ga, 57.7%; 35S, 26.0%; 111In, 21.1%; 201Tl, 16.6%; 123I, 11.9%; 131I, 8.2%; 125I, 2.4%; 14C, 0.39%; 3H, 0.04%. In the incineration of LLR S containing 35S, the rate of adhesion to the furnace wall was lower at high-temperature (809 degrees C) incineration than at low-temperature (376 degrees C) incineration. For LLRS containing one of the three radioiodines, 123I, 125I, or 131I, no such difference was observed between low (372 degrees C) and high (827 degrees C) temperature incineration (RF varied from 0.82 to 0.94).