A Novel Imaging Technique for Analyzing Condylar Movement During Mastication in Patients With Jaw Deformities: Four-Dimensional Computed Tomography

OBJECTIVE

This study aimed to reveal characteristic condylar movements in patients with jaw deformities.

STUDY DESIGN

Thirty patients with jaw deformities before surgery were enrolled and instructed to chew a cookie during 4-dimensional computed tomography (4DCT). The distance between the most anterior and posterior positions of the bilateral condyles on 4DCT images was measured and compared among patients with different skeletal classes. Correlations between the condylar protrusion and cephalometric values were also determined.

RESULTS

The distances of condylar protrusion during mastication were significantly greater in the skeletal class II group than in the skeletal class III group ( P =0.0002). Significant correlations were found between the distances of condylar protrusion during mastication and the sella-nasion-B point angle ( r =-0.442, P =0.015), A point-nasion-B point angle ( r =0.516, P =0.004), sella-nasion plane to ramus plane angle ( r =0.464, P =0.01), sella-nasion plane to occlusal plane angle ( r =0.367, P =0.047), and condylion-gonion length ( r =-0.366, P =0.048).

CONCLUSION

Motion analysis with 4DCT images revealed that condylar movement in patients with retrognathism was larger than in patients with mandibular prognathism. Skeletal structure was therefore correlated with condylar movement during mastication.

Risk factors for pathological fracture in patients with mandibular osteoradionecrosis

Osteoradionecrosis (ORN) often results in pathological fractures through progression. We aimed to identify the risk factors for pathological fracture in patients with mandibular ORN. Seventy-four patients with mandibular ORN were included in this retrospective study. We investigated various risk factors for pathological fracture in patients with mandibular ORN, including number of mandibular teeth with a poor prognosis each at initial evaluation before radiation therapy (RT) and when fracture occurred, and the proportion of antibiotic administration period in a follow-up duration after RT. The rate of occurrence of pathological fractures in patients with mandibular ORN was 25.7%. The median of duration between RT completion and fracture occurrence was 74.0 months. We found that pathological fracture was significantly associated with a larger number of mandibular teeth with a poor prognosis at initial evaluation before RT (P = 0.024) and when fracture occurred (P = 0.009). Especially, a larger number of mandibular teeth with P4 periodontitis, in other words severe periodontal status, was related to pathological fracture in both timings. The proportion of antibiotic administration period in a follow-up duration was also significant risk factor (P = 0.002). Multivariate analyses showed statistically significant associations between pathological fracture and a larger number of mandibular teeth with a poor prognosis when fracture occurred (hazard ratio 3.669). The patient with a larger number of mandibular teeth with P4 periodontitis may have a risk of not only occurrence of ORN but resulting in pathological fracture by accumulation of infection. Surgeons should consider extraction of those teeth regardless of before/after RT if necessary for infection control.

S-1 and irinotecan plus bevacizumab versus mFOLFOX6 or CapeOX plus bevacizumab as first-line treatment in patients with metastatic colorectal cancer (TRICOLORE): a randomized, open-label, phase III, noninferiority trial

Background

Combination therapy with oral fluoropyrimidine and irinotecan has not yet been established as first-line treatment of metastatic colorectal cancer (mCRC). We carried out a randomized, open-label, phase III trial to determine whether S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab in terms of progression-free survival (PFS).

Patients and methods

Patients from 53 institutions who had previously untreated mCRC were randomly assigned (1 : 1) to receive either mFOLFOX6 or CapeOX plus bevacizumab (control group) or S-1 and irinotecan plus bevacizumab (experimental group; a 3-week regimen: intravenous infusions of irinotecan 150 mg/m2 and bevacizumab 7.5 mg/kg on day 1, oral S-1 80 mg/m2 twice daily for 2 weeks, followed by a 1-week rest; or a 4-week regimen: irinotecan 100 mg/m2 and bevacizumab 5 mg/kg on days 1 and 15, S-1 80 mg/m2 twice daily for 2 weeks, followed by a 2-week rest). The primary end point was PFS. The noninferiority margin was 1.25; noninferiority would be established if the upper limit of the 95% confidence interval (CI) for the hazard ratio (HR) of the control group versus the experimental group was less than this margin.

Result

Between June 2012 and September 2014, 487 patients underwent randomization. Two hundred and forty-three patients assigned to the control group and 241 assigned to the experimental group were included in the primary analysis. Median PFS was 10.8 months (95% CI 9.6-11.6) in the control group and 14.0 months (95% CI 12.4-15.5) in the experimental group (HR 0.84, 95% CI 0.70-1.02; P < 0.0001 for noninferiority, P = 0.0815 for superiority). One hundred and fifty-seven patients (64.9%) in the control group and 140 (58.6%) in the experimental group had adverse events of grade 3 or higher.

Conclusion

S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab with respect to PFS as first-line treatment of mCRC and could be a new standard treatment.

Clinical trials number

UMIN000007834.

Haemagglutination and glycolipid-binding activities of Lactobacillus reuteri

The carbohydrate-binding activity of Lactobacillus reuteri was studied by haemagglutination (HA), HA inhibition and thin layer chromatography (TLC) overlay assays. Three of the six Lact. reuteri strains examined showed HA activity. Two strains (JCM1081 and JCM1112T) agglutinated neuraminidase-treated, but not untreated, erythrocytes. Strain JCM2762 agglutinated both treated and untreated erythrocytes. The HA activity of JCM 1081 was inhibited by galactose, lactose, methyl beta-galactoside and asialoglycophorin A. Among 12 glycosphingolipids, TLC overlay assay showed that JCM1081 strongly bound to asialo-GM1. These results indicated that JCM1081 bound to the beta-galactosyl residues of the non-reducing terminal of sugar chains of glycoconjugates. The carbohydrate-binding ability of JCM1081 may be responsible for the adhesion of this strain to the mucosal surface of the intestine.

Collagen binding of Bifidobacterium adolescentis

In this study, 13 bifidobacterial strains were tested for their ability to adhere to immobilized extracellular matrix (ECM) proteins. Only two Bifidobacterium adolescentis strains adhered to immobilized type I and type V collagens, but not to laminin, fibronectin, and type III and IV collagens. The adhesion of B. adolescentis BB-119 to type V collagen was inhibited by type I and V collagens and gelatin, and was diminished after protease treatment of the cells. Periodate treatment of immobilized collagen and the presence of galactose inhibited the adhesion of strain BB-119 to type V collagen. Two cell surface proteins with molecular masses of 36 kDa and 52 kDa from strain BB-119 were found to bind to horseradish peroxidase-conjugated type V collagen by ligand blotting. We concluded that B. adolescentis BB-119 binds to type V collagen at galactose chains as target via these two cell surface proteins by their lectin-like activity.

Depletion of dietary sulphamonomethoxine and sulphadimethoxine from various tissues of laying hens

Sulphamonomethoxine (SMM) or sulphadimethoxine (SDM) was fed to laying hens at 400 mg/kg diet for 5 successive days. After withdrawal of the drugs, contents (mg/kg) of SMM and SDM in the blood, kidney, liver, ovary, muscle and adipose tissue were determined by HPLC. 2. The disappearance of dietary SMM and SDM from the tissues of laying hens was rapid and, except for the liver, was very similar in all tissues. 3. A common biological half-life (t1/2) of SMM in the above 6 tissues was estimated to be 5.2 h. The t1/2 of SDM in the liver was 6.9 h, significantly longer than that of 4.4 h in the other 5 tissues. The values were much shorter than 51/2 (reported elsewhere) for other drugs. 4. Comparing the data found in this study with those obtained from previous papers, the depletion velocities of SMM and SDM from the hen's body were much faster than those from albumen in egg. The reason for this is probably related to the longer time period over which albumen formation occurs.

Prevalence of precore-defective mutant of hepatitis B virus in HBV carriers

Two hundred and seventy-three serum specimens from hepatitis B virus (HBV) carriers were examined for the presence of a characteristic one point mutation at nucleotide (nt) 1896 from the EcoRI site of the HBV genome in the precore region (the preC mutant) using restriction fragment length polymorphism (RFLP) analysis. This assay approach could detect preC mutants or wild-type sequences when either form constituted more than 10% of the total sample. Overall, 65.5% (76/116) of HBeAg-positive carriers had only the preC wild-type. All HBeAg-positive asymptomatic carriers (n = 14) had only the preC wild-type. In patients with chronic hepatitis B and in anti-HBe-positive asymptomatic carriers, increased prevalence of the preC mutant was associated with the development of anti-HBe antibodies and normalization of the serum alanine aminotransferase concentration. Furthermore, 27 (29.0%) of 93 HBeAg-negative carriers had unexpectedly preC wild-type sequences only. Direct sequencing of the HBV precore region of HBV specimens from 24 patients revealed no mutation at nt 1896, supporting the specificity of the RFLP analysis. These results suggest that RFLP analysis was accurate for the detection of the preC mutation and that the absence of serum HBeAg cannot be explained solely by the dominance of the preC mutant.

Changes of serum hepatitis C virus levels in patients with chronic hepatitis C treated with two courses of interferon administration

To assess the efficacy of repeated interferon (IFN) administration in patients with chronic hepatitis C unresponsive to initial therapy, serum hepatitis C virus (HCV)-RNA levels were measured in 12 patients who had failed prior IFN therapy. Serum HCV-RNA was assayed by measuring DNA complementary to HCV-RNA using a quantitative reverse transcription-polymerase chain reaction assay. The mean total dose of IFN was 227.8 mega-units for first treatment and 270.7 mega-units for second treatment. Five responders with a normal alanine aminotransferase (ALT) concentration (less than 40 IU/liter) at the end of the first treatment also had a normal ALT concentration at the end of the second treatment. By contrast, all nonresponders with an elevated ALT concentration during the first treatment likewise had an elevated ALT concentration at the end of the second treatment. HCV-RNA levels before the first treatment varied from 10(6) to 10(8) copies/microliters. The serum HCV-RNA levels fell in 9 out of 10 patients after the first treatment and in 11 out of 12 patients after the second treatment. One patient had unchanged normal serum ALT levels after two courses of IFN treatment. These results suggested that the outcome of a second course of IFN treatment was similar biochemically and virologically to a first course, and that patients who did not respond initially seldom respond to additional IFN therapy. Therefore, readministration of IFN should be restricted to patients who respond biochemically and virologically to initial treatment. The optimal second dose shall be determined with further studies.

Two cases of porphyria cutanea tarda associated with chronic hepatitis positive for the antibody against hepatitis C virus

We report two cases of porphyria cutanea tarda (PCT) positive for the antibody against hepatitis C virus (anti-HCV). The serological and histological examinations revealed that they were persistently infected with HCV and were suffering from liver disease compatible with chronic viral hepatitis. It is suggested that one of the factors which contribute to liver damage of patients with PCT may be HCV infection. It now may be advisable to examine anti-HCV in PCT patients with liver disease.

Relationship between molecular state of serum HBV-DNA and clinical features of hepatitis B virus carriers

Molecular species of serum hepatitis B virus (HBV)-DNA in HBV carriers were classified by Southern blot hybridization into three types; type I with two bands of 4.0 kb and 3.2 kb, type II with the two bands of type I plus the smear between 4.0 kb and 3.2 kb, and type III with a broad band below 4.0 kb. A total of 51 HBV carriers were classified into three groups (group I, n = 19 with type I; group II, n = 12 with type II; and group III, n = 20 with type III). Serum aminotransferase levels of group I were significantly lower than those of groups II and III. Liver pathology revealed that 18 of the 19 (94.7%) group I patients showed nonspecific reactive hepatitis (NSRH), while 11 of the 12 (91.7%) group II patients and 19 of the 20 (95.0%) group III patients showed chronic persistent hepatitis (CPH) or chronic active hepatitis (CAH). Immunohistochemical study showed that hepatitis B core antigen (HBcAg) was localized in the nucleus of hepatocytes in most of patients with type I while it was localized in both the nucleus and cytoplasm in those with types II and III. Since the smear between 4.0 kb and 3.2 kb is specifically found in groups II and III, HBV-DNA with this smear may be related to active hepatitis.

Demonstration of hepatitis C virus genome in saliva and urine of patients with type C hepatitis: usefulness of the single round polymerase chain reaction method for detection of the HCV genome

The possible transmission routes of hepatitis C virus (HCV) in patients without overt parenteral exposure (sporadic or community acquired form) were examined. Saliva and urine specimens obtained from type C hepatitis patients, whose sera were positive for the HCV genome, were examined by reverse transcription and polymerase chain reaction (RT-PCR). By analyzing the factors that influenced the detection of the HCV genome by PCR, we developed a single round method which enabled semiquantitative detection with higher sensitivity than that obtained with nested PCR. Single round PCR revealed that 34.8% (8 of 23) of saliva and 56.5% (13 of 23) of urine specimens from patients with type C hepatitis contained the HCV genome. The amounts of HCV genome in saliva and urine specimens correlated with those in serum. The relative amounts of HCV genome in serum, saliva, and urine from a chronic type C hepatitis patient were determined by comparing the reciprocal of the smallest volume of the specimens in which the PCR products were visualized in agarose gels (PCR units/ml), and the values were 1 x 10(5), 5 x 10(1), and 3 x 10(1) PCR units/ml for serum, saliva, and urine specimens, respectively.

Three distinct Southern blot hybridization patterns of HBV-DNA in the sera of HBV carriers

The molecular species of hepatitis B virus (HBV)-DNA of 44 sera taken from 25 HBV carriers were examined by Southern blot hybridization with a biotin-labeled HBV-DNA probe and classified into three patterns. Type I consisted of two distinct bands of 4.0 kb and 3.2 kb. Type II consisted of the 4.0 kb and 3.2 kb bands and a smear between these two bands. Type III showed a broad band below 4.0 kb. With endogenous HBV-DNA polymerase reaction, the smear disappeared and 4.0 kb and 3.2 kb bands appeared. After EcoRI digestion, the 4.0 kb band disappeared to form a single band of 3.2 kb. These results suggest that the 4.0 kb and 3.2 kb forms are a relaxed circular, fully double-stranded DNA and a linear, fully double-stranded DNA, respectively, and that the smear between 4.0 kb and 3.2 kb is formed from the sum of relaxed circular, partially double-stranded DNAs with various length of plus strands. Comparison between histological diagnosis and Southern blot hybridization patterns of 25 HBV carriers indicates that these three patterns are closely related to the degree of hepatitis.

Helicobacter pylori infection and chronic atrophic gastritis among Japanese blood donors: a cross-sectional study

To evaluate an association between Helicobacter pylori (H. pylori) infection and chronic atrophic gastritis (CAG), an established precursor of gastric cancer, we performed a cross-sectional study using IgG antibody against H. pylori and pepsinogens of blood donors in four prefectures in Japan. Although a geographic correlation between the age-adjusted prevalence rates for H. pylori infection and those for CAG was not seen, the age-adjusted odds ratios (OR) of H. pylori infection for CAG were high in each area (around five for men and from four to 12.6 for women). The association between them weakened with advancing age; the ORs in the youngest age group (16-29 yrs) and in the oldest age group (50-64 yrs) were 12.5 and 2.8 for men, and 11.5 and 5.2 for women, respectively. These findings suggest that H. pylori infection is strongly associated with CAG, while there are some other factors interacting in the development of CAG. A prospective cohort study in which CAG and H. pylori infection are taken into account will be necessary to assess the risks of gastric cancer.

Intra- and extracellular distribution and immunochemical characterization of hepatitis B virus nucleocapsid proteins produced by a human hepatoma cell line transfected with cloned viral DNA

Hepatitis B virus (HBV)-related antigens produced by the human hepatoma cell line (HB611 cell), which had been transfected with a cloned HBV DNA and established as a stable producer of HBV (T. Tsurimoto, A. Fujiyama, and K. Matsubara, 1987, Proc. Natl. Acad. Sci. USA 84, 444-448), were investigated immunochemically and morphologically. All HBV-related antigens, HBV surface (HBsAg), e (HBeAg), and core (HBcAg), were semiquantitatively examined by the respective reversed passive hemagglutination assay (RPHA). RPHAs for HBcAg and for HBeAg were characterized as reacting only to the core particles and to the free form of nucleocapsid proteins, respectively. The amounts of HBsAg and nucleocapsid protein in culture medium were roughly related to the number of viable cells. The amount of core particles was, instead, proportional to the number of dead cells. Relative amounts of HBsAg, core particles, and nucleocapsid proteins in culture medium, cell surface, and cell lysate were determined and it was found that HBsAg and nucleocapsid proteins were effectively secreted into culture medium but core particles were not. Molecular species of nucleocapsid proteins were identified to be p17 and p18 (HBeAg polypeptides) in the culture medium and HBeAg polypeptides and p21.5 (HBcAg polypeptide) in the cytosol fraction. The p21.5 was preferentially found in the nuclear fraction.

DNA-binding activity of hepatitis B e antigen polypeptide lacking the protaminelike sequence of nucleocapsid protein of human hepatitis B virus

The characteristics of binding of hepatitis B core antigen (HBcAg) and hepatitis B e antigen (HBeAg) polypeptides to hepatitis B virus (HBV) DNA were analyzed. HBcAg polypeptide from recombinant HBV core particles and HBeAg polypeptide from partially purified serum HBeAg were prepared and verified to have molecular weights of 21,500 (P21.5) and of 17,000 (P17) and 18,000 (P18), respectively, by immunoblot analysis. By reaction of these proteins on a nitrocellulose membrane with cloned 32P-HBV DNA, it was revealed that the HBeAg polypeptide, which lacks the C-terminal 34 amino acids of P21.5, as well as the HBcAg polypeptide, bound to the DNA. The secondary structures of nucleocapsid proteins of HBV, woodchuck hepatitis virus, and ground squirrel hepatitis virus were predicted by the Garnier algorithm. Amino acid sequences which, in addition to those of the C-terminal regions, may contribute to binding were proposed to be the 21-amino-acid residues located at amino acids 100 to 120 of the nucleocapsid proteins of these hepadnaviruses.

Immunochemical characteristics of hepatitis B e antigen subspecificities, HBeAg/1 and HBeAg/2

The molecular interrelation between hepatitis B e Ag 1 (HBeAg/1) and HBeAg/2 was examined immunochemically. Major polypeptides with m.w. around 17,000 (P17) and one minor polypeptide with m.w. 18,000 (P18) that had HBeAg activity were consistently detected in 12 different serum samples by immunoblotting analysis. To examine the polypeptide composition of HBeAg/1 and HBeAg/2, precipitin lines of HBeAg/1-anti-HBeAg/1 and HBeAg/2-anti-HBeAg/2 were separately cut from the agarose gel and analyzed by immunoblotting. HBeAg/1 and HBeAg/2 showed similar P17 and P18 compositions. Monomeric forms of P17 and P18 in a solution of 0.1% SDS showed HBeAg/1 activity, whereas polymeric forms of these polypeptides showed HBeAg/2 activity. The stability of HBeAg subspecificities to SDS and 2-ME was examined. When HBeAg was incubated in a buffer containing 0.1% SDS and 0.1% 2-ME, only the HBeAg/2 precipitin line disappeared in agarose gel concurrently with the conversion of HBeAg molecules to a monomeric from a polymeric form. In contrast, neither monomerization nor the disappearance of HBeAg/2 was seen when SDS or 2-ME was used by itself. These results indicate that hydrophobic forces and disulfide bonds may be involved in the association of P17 and P18 in serum and that HBeAg/2 activity depends upon association of HBeAg-polypeptides but that HBeAg/1 activity does not. The possibility that the epitopes of HBeAg/2 are specific for the conformation of polymerized molecules is discussed.

Immunochemical characteristics of hepatitis B e antigen subspecificities, HBeAg/1 and HBeAg/2

The molecular interrelation between hepatitis B e Ag 1 (HBeAg/1) and HBeAg/2 was examined immunochemically. Major polypeptides with m.w. around 17,000 (P17) and one minor polypeptide with m.w. 18,000 (P18) that had HBeAg activity were consistently detected in 12 different serum samples by immunoblotting analysis. To examine the polypeptide composition of HBeAg/1 and HBeAg/2, precipitin lines of HBeAg/1-anti-HBeAg/1 and HBeAg/2-anti-HBeAg/2 were separately cut from the agarose gel and analyzed by immunoblotting. HBeAg/1 and HBeAg/2 showed similar P17 and P18 compositions. Monomeric forms of P17 and P18 in a solution of 0.1% SDS showed HBeAg/1 activity, whereas polymeric forms of these polypeptides showed HBeAg/2 activity. The stability of HBeAg subspecificities to SDS and 2-ME was examined. When HBeAg was incubated in a buffer containing 0.1% SDS and 0.1% 2-ME, only the HBeAg/2 precipitin line disappeared in agarose gel concurrently with the conversion of HBeAg molecules to a monomeric from a polymeric form. In contrast, neither monomerization nor the disappearance of HBeAg/2 was seen when SDS or 2-ME was used by itself. These results indicate that hydrophobic forces and disulfide bonds may be involved in the association of P17 and P18 in serum and that HBeAg/2 activity depends upon association of HBeAg-polypeptides but that HBeAg/1 activity does not. The possibility that the epitopes of HBeAg/2 are specific for the conformation of polymerized molecules is discussed.

Severe acute exacerbation in chronic hepatitis B virus infection in Sendai, Japan

In order to examine the clinical features of severe acute exacerbation in chronic hepatitis B virus (HBV) infection, 297 hepatitis B surface antigen (HBsAg) carriers were followed for 35 +/- 22 months (mean +/- S.D.) in Tohoku University Hospital from 1976 to 1987. Of these, 10 experienced severe acute exacerbation with hepatic decompensation. All of these patients had intense subjective symptoms related to the hepatitis. They were all icteric and 8 had ascites. Three developed to fulminant hepatic failure, eventually died. Histology after the exacerbation showed severe hepatic damage such as massive hepatic necrosis and bridging hepatic necrosis in a half of them. Six cases were suspected to result from spontaneous reactivation and 2 from drug-induced reactivation of chronic HBV infection, and the other 2 from superinfection with non-A, non-B hepatitis agent (s). These results suggest that the reactivation of chronic HBV infection is an important factor of severe acute exacerbations in chronic HBV infection in Japan.

Relationship between the replication of hepatitis B virus and the localization of virus nucleocapsid antigen (HBcAg) in hepatocytes

According to the localization of hepatitis B virus (HBV) core antigen (HBcAg), detected by the avidin-biotin complex method, infected hepatocytes were classified into three types, i.e. those having nuclear (type I), nuclear and cytoplasmic (type II) or only cytoplasmic (type III) antigen. HBcAg-positive hepatocytes of all specimens (three) from non-specific reactive hepatitis and of most (five of seven) from chronic persistent hepatitis (CPH) patients were only type I; the other two CPH samples and all (seven) chronic active hepatitis samples were composed of a mixture of types I, II and III. Linear correlations between the frequency of type I, as well as that of of all types (I, II and III) of the HBcAg-positive hepatocytes, and the amount of HBV DNA in serum were found. The relative HBV production of HBcAg-positive hepatocytes (serum HBV DNA amount/frequency of HBcAg-positive cells) was 0.11 in type I and 0.07 in all hepatocytes including types I, II and III. HBV core particles and complete HBV particles were found in type I hepatocytes. On the other hand, these particles were not found in a predominantly type III liver specimen. These results suggest that type I hepatocytes are more involved in the propagation of HBV than types II and III.

Virological significance of HBeAg subtypes (HBeAg/1 and HBeAg/2) in patients with type B hepatitis

In order to establish the virological significance of HBeAg subtypes (HBeAg/1 and HBeAg/2) during hepatitis B virus infection, HBsAg, HBeAg and hepatitis B virus DNA in serum and HBcAg in liver were determined quantitatively in relation to the detection of HBeAg subtypes in agar gel diffusion. Thirty-eight chronic HBsAg carriers with HBeAg, including 16 non-specific reactive hepatitis, 8 chronic persistent hepatitis, 11 chronic active hepatitis and 3 liver cirrhosis, who were seen at Tohoku University Hospital from 1983 to 1985, were examined. Significantly larger amounts of HBsAg, HBeAg and hepatitis B virus DNA in serum and HBcAg in liver were found in patients positive for both HBeAg/1 and HBeAg/2 in serum than in those positive for only HBeAg/1 or negative for both subtypes. These results suggest that the presence of HBeAg/2 in serum may reflect the occurrence of active viral replication. When the detection pattern of HBeAg subtypes was examined during serial follow-up for at least 1 year, three groups of patients were classified with respect to the presence of HBeAg/2, i.e., Type I, consistently positive for HBeAg/2; Type II, consistently negative for HBeAg/2, and Type III, intermittently positive for HBeAg/2. More than 80% of Type I patients were histologically diagnosed having as nonspecific reactive hepatitis, while more than 80% of Type II and III patients had more progressive liver diseases such as chronic persistent hepatitis, chronic active hepatitis and liver cirrhosis. These results suggest that the serial examination of HBeAg subtypes in serum may be important for more detailed evaluations of type B hepatitis.

Immunochemical characterization of hepatitis B e antigen subtypes, HBeAg/1 and HBeAg/2, in sera of hepatitis B virus carriers

The interrelation between HBeAg subtypes, HBeAg/1 and HBeAg/2, in sera was examined immunochemically. The detection of HBeAg subtypes in immunodiffusion (ID) depended upon the amount of HBeAg determined by reversed passive haemagglutination (RPHA), ie, the titres of HBeAg in sera positive for both HBeAg/1 and HBeAg/2, positive for only HBeAg/1 and negative for both HBeAg/1 and HBeAg/2 were 2(9.8) +/- 1.5, 2(7.0) +/- 1.6, and 2(5.6) +/- 1.3, respectively. When the sera belonging to the latter two groups were concentrated up to 2(10) RPHA titre, the precipitin line corresponding to that of HBeAg/2-anti-HBeAg/2 was visualized in ID. Monoclonal anti-HBeAg antibody that absorbed only the precipitin line of HBeAg/1-anti-HBeAg/1 in ID was prepared for the characterization of HBeAg subtypes. A linear correlation (r = 0.91) between titres of HBeAg determined by the RPHA cells prepared with monoclonal and polyclonal antibodies was found in almost all HBeAg-positive sera. The reactivities of this monoclonal anti-HBeAg antibody to both HBeAg/1 and HBeAg/2 were demonstrated in affinity chromatography experiments using a Sepharose 4B column conjugated with this antibody. These results suggest that both HBeAg/1 and HBeAg/2 are constantly present in HBeAg-positive sera and that they are closely associated. Based upon these results, a hypothetical model for the elucidation of the immunological relationship between HBeAg/1 and HBeAg/2 is proposed.

Establishment of passive hemagglutination assay (PHA) system for anti-HBc in plasma

A sensitive and specific assay system for anti-HBc, the passive hemagglutination (PHA) method, has been established. The reactivity of PHA cells prepared by conjugating purified recombinant HBcAg-particles with fixed sheep blood cells (SRBC) was highly specific to monoclonal- and polyclonal anti-HBc IgGs. The sensitivity of PHA method was higher than that of radioimmunoassay (RIA). However, uncertainty for the positivity of anti-HBc still remained in plasma with the PHA titers lower than 2(5). A relatively high ratio (19%, 37 of 196) of anti-HBc-positive plasma, which had been confirmed to be HBsAg negative, was demonstrated in blood donors whose bloods have been considered suitable for transfusion. The hazards of anti-HBc-positive bloods and the importance of anti-HBc detection in plasma are discussed in this paper.

Seroepidemiological studies on a non-A, non-B hepatitis specific antigen/antibody system (SO-antigen/anti-SO)

The patients and staff members of a haemodialysis unit were examined for their serological responses to SO-antigen, which was isolated from the urine of epidemic type non-A, non-B hepatitis patients at Tohoku University Hospital. To understand how SO-antigen or SO-antigen-related aetiology can be incriminated for the hepatitis found in the haemodialysis unit, the prevalence of SO-antigen/anti-SO system and hepatitis A and B virus-related antibodies was compared in the sera of patients and staff members. Although the SO-antigen was rarely detected in the serum, anti-SO antibody was frequently detected in the sera of patients and staff. A significantly higher prevalence was found in the serum of patients (15%, 54 out of 361) than staff members (7.1%, 13 out of 184) and volunteer blood donors (1%, 3 out of 305). The same prevalence percentages of HBV-related antibodies (either positive for anti-HBs or anti-HBc) and anti-HAV were observed among the patients, staff, and volunteer blood donors, irrespective of whether the sera were anti-SO positive or negative. Among the staff, anti-SO antibody was more frequently found in those with a history of acute hepatitis (16.7%, 3 out of 18) than in those without (6%, 10 out of 166). These prevalence ratios conformed with those of HBV-related antibodies, but the same prevalence ratios of antibody to HAV were observed between the staff with and without a history of acute hepatitis. These results indicate that the SO-antigen/anti-SO system or entity related to this immune system is distinct from HBV or HAV, and this immune system was found widely in the haemodialysis unit where type B and non-A, non-B hepatitis were also found frequently.

Virological classification of autopsy livers with hepatic disorders

Forty six selected autopsy livers with hepatic disorders were classified histologically into three groups, i.e., hepatitis 8, liver cirrhosis 16 and hepatocellular carcinoma 22, chiefly by histological findings. These groups were subdivided into two categories after determining the presence or absence of three HBV associated markers, i.e., the hepatitis B surface antigen (HBsAg), the antibody to hepatitis B surface antigen (anti-HBs) and the antibody to hepatitis B core antigen (anti-HBc) in the sera and liver homogenates. At least one of these markers was found to be present in the sera and homogenates of 38% of the livers with hepatitis, 69% of the livers with liver cirrhosis and 77% of the livers with hepatocellular carcinoma. When the liver tissues were examined for the presence of HBV DNA using Southern blot technique, the majority of them (10 out of 11) which proved to be positive for at least one HBV associated marker were also positive for HBV DNA. However, HBV DNA could not be detected in the other 10 livers which contained no HBV associated markers. These results showed that a HBV associated serological marker was always expressed, when liver tissue HBV DNA was demonstrable. The results of the two detection methods we used in this study were found to be almost equivalent. These results showed no evidence of nucleic acid homology between DNA from the liver of patients with non-B type liver disorders and HBV DNA.

Immunological and morphological properties of HBeAg subtypes (HBeAg/1 and HBeAg/2) in hepatitis B virus core particles

A polypeptide of 21 500 mol. wt., structurally associated with hepatitis B virus core particles, was shown to have two kinds of HBeAg antigenicity (HBeAg/1 and HBeAg/2). This was revealed by transferring a single core peptide from polyacrylamide gels to nitrocellulose sheets (Western blotting), which reacted with anti-HBeAg/1 and anti-HBeAg/2. Selective discrimination of the two HBe antigens was achieved by radioimmunoassay (RIA). When highly purified core particles were incubated at 37 degrees C in a 0.1% SDS-0.1% 2-mercaptoethanol solution, only HBeAg/1 was released after 5 min incubation and the release of HBeAg/2 occurred only after prolonging incubation for 30 min. The course of degradation was also detected by CsCl density gradient centrifugation. These results indicate that HBeAg/1 is less closely associated with core particles than is HBeAg/2. Electron microscopy showed that the core particles from which HBeAg/1 was removed were more labile than the original preparation when incubated at 56 degrees C in aqueous solution, or at 37 degrees C in Sarkosyl solutions; when placed in 1 M-NaCl or -CsCl solution, the particles swelled to a larger diameter than untreated cores.

Two distinct types of non-A, non-B hepatitis in a cardiovascular surgical unit

The incidence of non-A, non-B hepatitis in a cardiovascular surgical unit was examined among the 204 patients who received blood transfusion and extracorporeal circulation while undergoing open heart surgery during April 1979 to December 1981. Among 115 adult patients (20 to 69 years old) 46 (43%) developed non-A, non-B hepatitis, whereas the incidence in younger patients (1 to 19 years old) was much lower (21.8%, 19 out of 89). When monthly incidence was examined during the study period, two nosocomial epidemics, the first during September 1979 to February 1980 and second during October 1980 to January 1981, were found. When clinical features such as maximum ALT level and the proportion of icterus were examined, the features of the above two epidemics were taken to be different from those consistently observed through the study period. The epidemic type hepatitis not only resulted in more severe clinical features than the nonepidemic type, but the sera of the former contained immune complexes at a higher rate (80%) than did the latter (7.6%).

A risk index for the prediction of the incidence of non-A, non-B posttransfusion hepatitis in open-heart surgery patients

Risk factors related to the occurrence of non-A, non-B posttransfusion hepatitis (PTH) were statistically analyzed in 204 patients (115 adults and 89 children) who received blood transfusion and extracorporeal circulation during open-heart surgery. The PTH incidence, irrespective of age or body weight, was affected by both transfusion volume and circulation time, ie, the incidence increased cumulatively with the increment of these two variables. Based upon such statistical analysis, a "PTH-risk index," from which one can objectively predict the probability of PTH, was devised by the summation of standardized transfusion volumes (Vs) and circulation time (Ts). As a result, a high correlation between the obtained PTH-risk index and actual incidence was found. The obtained straight regression line between PTH-risk index and the actual incidence rate enabled us to predict the incidence of PTH in open-heart surgery patients.

An antigen/antibody system specific for an epidemic non-A, non-B hepatitis in patients of a cardiovascular surgical unit

The antigen/antibody systems specific for non-A, non-B hepatitis (NANB) were studied using urine samples as the antigen source and sera for the antibody source. Two immunologically distinct systems, SO-antigen/anti-SO and MI-antigen/anti-MI were discovered. This paper deals chiefly with the characterization of the SO-antigen, which was associated with an epidemic-type non-A, non-B hepatitis found during September 1979 to February 1980 (first outbreak) and October 1980 to January 1981 (second outbreak) in the Cardiovascular Surgical Unit of Tohoku University Hospital. All patients who developed non-A, non-B hepatitis during the first and second epidemic periods had SO-antigen in their urine (24 out of 24). After the epidemic, however, the detection rate of SO-antigen gradually decreased among patients in the same unit, although posttransfusion non-A, non-B hepatitis continued to be found. The final detection of SO-antigen occurred at or just after the elevation of alanine aminotransferase (ALT) levels during the episode of hepatitis and persisted in most cases throughout the elevated period. Anti-SO antibody was detected relatively late (eight months after blood transfusion, in most cases) and apparently persisted longer than five years. The immunological and physicochemical properties of SO-antigen were also studied. It appeared to be neither a plasma protein nor a liver tissue component when the cross-reactivity of SO-antigen was examined by the immunodiffusion method. Absorption with insolubilized human serum and liver tissues failed to affect the anti-SO antibody activity. The molecular weight of SO-antigen was estimated to be 250,000, the sedimentation coefficient to be 11.0 S, and the buoyant density in CsCl to be 1.215 g/cm3. Electron microscopy showed that the SO-antigen corresponded with uniform particles with a mean diameter of 11 nm. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of SO-antigen revealed only a single protein band corresponding to molecular weight 38,000.

Circular dichroism and biochemical properties of the hepatitis B virus core antigen

The hepatitis B virus (HBV) core antigen was purified by mild procedures, including hydroxyapatite column chromatography, with care taken to avoid the degradation of the particles. Circular dichroism (CD) of the HBV core particles in saline showed low intensities of negative ellipticities in the region dominated by amide bond absorption. Acid treatment of the particles induced a remarkable change in the CD spectrum, with the appearance of a positive extremum at about 208 nm. The amino acid composition and the COOH-terminal residue of the isolated core polypeptide (Mr 21,000-21,500) were shown to be essentially the same as those of the polypeptide deduced from the nucleotide sequences which had been proposed for the HBV core antigen by other laboratories. We failed to detect any NH2-terminal dansyl-derivatives from the core polypeptide by the dansyl-Edman method. We also showed by the method of fluorescein polarization that the core polypeptide conjugated with fluorescein isothiocyanate has an affinity for serum albumin. This may indicate a state of disassembled or non-assembled core polypeptide in sera.

Electron microscopy of human hepatitis B virus cores by negative staining-carbon film technique

The ultrastructure of the nucleocapsid component of human hepatitis B virus (core particle) was studied by negative staining-carbon film technique. Using this method an improved image of core particles was obtained in respect of resolution and contrast. Two-dimensional crystalline arrays of core particles were formed in vitro. Under these arrays the distance between the particle centers was 28.3 nm, corresponding to the capsid diameter, when analyzed through optical diffraction patterns. Positively stained images of these arrays revealed that core particles contain an electron-dense center of nucleoid-like area about 21 nm in diameter. The capsid surface rarely exhibited small capsomeres, ie, small spheres or ring-like structures measuring 4.0-4.2 nm. From the dimension of these structures and the analysis by Markham's rotational technique, it was suggested that each of these capsomeres is an individual subunit (monomer) and 180 of these subunits build up the core particle capsid according to the icosahedral symmetry (T = 3), but not clustering into distinct morphological features.

Molecular heterogeneity of hepatitis B virus e antigen in liver and serum

Hepatitis B virus e antigen (HBeAg) derived from liver at autopsy or from the serum of asymptomatic carriers has been characterized. The liver-derived HBeAg consisted of two different molecules, one with a mol. wt. of 30 000 (monomer) and the other with a mol. wt. of 90 000 (trimer), in a ratio of 3:1. Both were free of IgG. The serum-derived HBeAgs were heterogeneous with mol. wt. of 30 000, 90 000, 240 000, 400 000 and 540 000. Among them, the so-called IgG-free HBeAgs consisted almost exclusively of the 30 000 and 90 000 molecular species, in a ratio of 1:9. The serum HBeAg of mol. wt. 90 000 was further differentiated into two molecular species, one trimer and the other associated with albumin. The large mol. wt. HBeAgs (240 000, 400 000 and 540 000) were associated with IgG in ratios of one molecule of HBeAg to one, two or three molecules of IgG respectively. The complete dissociation of the IgG molecule was not achieved by 5 M-urea treatment of such HBeAgs, suggesting that it was bound in an immune complex. A hypothetical model is proposed which describes the heterogeneity of the HBeAgs derived from both the liver and serum, and containing HBeAgs either in a free form or associated with serum IgG.

Antigenic conversion from HBcAg to HBeAg by degradation of hepatitis B core particles

Highly purified and homogenous hepatitis B core particles were obtained from an autopsy liver. The core particles consisted mainly of an electrophoretically single major polypeptide with a molecular weight of 20,000 daltons. When antigenic conversion from hepatitis B core antigen (HBcAg) to hepatitis B e antigen was achieved by treating these core particles by sonication or by passing them through an anti-HBc IgG-conjugated Sepharose 4B column, no appreciable changes were found in the above protein composition. The same antigenic conversion was also achieved by centrifugation of core particles in CsCl, which revealed the process of morphological disintegration accompanied by antigenic conversion. These observations may support the hypothesis that HBcAg resides on a protein conformation which consists of a polypeptide sharing HBe antigenicity.

Prevalence of Williams e1 antigen in comparison with e2 antigen in hepatitis B antigen carriers and patients in hemodialysis unit

The prevalence of both e1 and e2 antigens in 1,158 sera of asymptomatic HBsAg carriers, carriers in hemodialysis units, and HBsAg-negative blood donors was examined. The detection rate of e1 antigen was as high as 80% in asymptomatic carriers, 95% in hemodialysis patients, and even 13.1% in HBsAg-negative donors. All of the e1 antigen-positive specimens in such HBsAg-negative sera were found to have both or either anti-HBs and anti-HBc, suggesting the past history of Hepatitis B virus (HBV) infection of the donors. In the HBsAg-positive serum, the detection rate of e2 antigen (17%) was lower than that of e1 (80%), and all sera having e2 antigen were positive for e1 antigen. The titers of HBsAg, HBcAg, and anti-HBc in e2 antigen-positive sera were higher than that of sera detecting only e1 antigen. The appearance of e1 antigen and e2 antigen in the course of post-transfusion hepatitis B was studied with five cases. Retrospective study showed that three of them each received one unit of HBsAg-positive blood, and the other two received HBsAg-negative blood but with high-titered anti-HBc. In four cases out of five, in which e2 antigen was detected during the course of infection, the initial detection of e2 antigen occurred at or just before the elevation of liver enzyme levels. On the other hand, e1 antigen was detected relatively early after transfusion, and the time of onset. Moreover, the detection period of e1 antigen persisted longer, even after the disappearance of HBsAg antigenemia. These two separate studies suggest that not only e2 antigen but also e1 antigen are associated with the infection of HBV, but they are distinct from each other; the e2 antigen may have the properties of a signal of the viral activity in the patient as suggested by many others, but e1 antigen does not seem to bear such diagnostic values.

Demonstration of hepatitis B e antigen (HBeAg) in association with intact Dane particles

Mild detergent treatment (0.1% Sarkosyl-0.1% beta-mercaptoethanol) of Dane particle-rich fraction from human serum resulted in the release of core particles together with HBe antigen activity when examined by the reversed passive haemagglutination method. Furthermore, when the core particles isolated by the above procedure were exposed to stronger detergent (1% Sarkosyl-0.1% beta-mercaptoethanol), additional HBe antigen activity was released only from intact core particles with DNA polymerase activity and not from empty core particles.

Physicochemical heterogeneity of hepatitis B e antigen detected in asymptomatic carriers and carriers in a hemodialysis unit

Physicochemical studies of hepatitis B e antigen (HBeAg) revealed a clear cut difference between e1 and e2 antigen. The e1 antigen was found to have a MW of Ca 150,000 and a pI of 6.4-7.2, whereas both the MW and pI of the e2 antigen were heterogeneous depending upon the source of serum. Sera obtained from asymptomatic carriers were characterized by low titers of HBs antigen, HBc antigen and DNA polymerase and contained e2 antigen of larger molecular weight (200,000-300,000) with a narrow distribution range and a pI of 4.8 to 5.2 (type 1). On the other hand, the sera from patients in a hemodialysis unit who were HBs antigen carriers and had high titers of HBs antigen, HBc antigen and DNA polymerase contained e2 antigen of heterogeneous distribution in MW (from 300,000 to 70,000) and pI (type 2 and 3). The e2 antigen obtained from the higher MW type 3 serum had lower isoelectric points (pI 4.5 to 5.2) as was the case with e2 antigen obtained from asymptomatic carriers whereas relatively wide range of isoelectric points (pI 5.1 to 8.2) was found with the lower molecular weight e2 antigen.

Evidence for the multiplication of hepatitis B virus in "oval cell" culture originated from human embryonic liver

Growth conditions fof human oval cells (immature hepatocytes),evidence of hepatitis B (HB) antigen synthesis in oval cells as revealed by immunofluorescent staining and successful passage of such an agent in the culture fluid up to the 4th passage are described. The results have been proved to be readily reproducible with different inocula. The oval cells used in these experiments were defined as small round cells, with scant cytoplasm, vesicular nuclei and small nucleoli, vitally stained with indocyanine green and synthesizing alpha-foetoprotein but no albumin.