Nutritional status and clinical outcome of uremic patients after high doses of hemodialysis

The effects of high doses of hemodialysis on the nutritional status, morbidity and mortality of 85 metabolically stable chronic hemodialysis patients were studied. Urea kinetic studies showed Kt/Vurea 1.8 +/- 0.4, mean time-average concentration of urea (TAC) 48.4 +/- 11 mg/dL and protein catabolic rate (PCR) 1.3 +/- 0.3 g/kg/d. All patients were followed up over a 12-month period with blood biochemistry and anthropometry measurements. The total number of hospitalizations and mortality were also recorded. Study results showed positive correlations between PCR and Kt/V, and PCR and TAC. Age was negatively correlated with serum albumin. A PCR < 1.0 g/kg/d (n = 14) was highly associated with more hospital admissions than those with a PCR > or = 1.0 g/kg/d (n = 71). There was no significant difference in biochemical nutritional indices and urea kinetic study between diabetic patients and non-diabetic patients, while aged patients (> or = 65 years) had significant lower serum albumin and hematocrit. A significant number of patients had anthropometric measurements below the 10th percentile, when compared with the standard for the Taiwan area. No difference was found in the effect of diabetes mellitus and time on hemodialysis on the anthropometric variables. The mortality rate was 4.7% (4/85), and all deaths involved patients over 65 years of age with either diabetic nephropathy or diffuse vascular disease. Despite high doses of dialysis, there was a high prevalence of subclinical malnutrition evidenced by anthropometric measurements. However, high doses of dialysis improved protein intake, nutritional status, as well as morbidity and mortality. Younger patients (< 65 years) had excellent results in this short-term study.

Unbiased usage of T-cell receptor beta variable region genes in peripheral blood cells of hepatitis C patients: no correlation with superantigen effect

Hepatitis C virus (HCV) infection frequently causes chronic hepatitis and lack of virus clearance in these patients. In addition, many patients infected by HCV also present with hypergammaglobulinemia in the early stage of chronic infection. These observations raise a possible viral superantigen effect induced by HCV, because viral superantigen found in human immunodeficiency virus (HIV) or in replication of defective murine leukemia virus (MuLV) is associated with T-cell dysfunction and polyclonal activation of B cells. The possibility was investigated of whether HCV encodes any superantigen by analyzing the usage of T-cell receptor (TCR) from the peripheral blood lymphocytes (PBL) of patients with chronic hepatitis C. Two groups, one with hypergammaglobulinemia and the other without hypergammaglobulinemia, were studied for the usage of TCR beta chain by reverse transcription-polymerase chain reaction (RT-PCR) analysis. It was found that all genes of V beta variable chain were used in the PBL of these patients. Furthermore, there was no significant difference of the TCR expression pattern between these two groups, nor a complete deletion of a particular T-cell subset in either group. These results do not provide evidence for HCV superantigen, but indicate that the TCR usage in the patients was neither defective nor biased.

Evaluation of third-generation hepatitis C antibody assay in chronic hepatitis C and chronic non-B, non-C hepatitis

Second-generation hepatitis C virus (HCV) antibody assays are more sensitive and specific than first-generation assays in the detection of HCV infection; such tests are widely used. However, there are still HCV-infected patients who test seronegative for anti-HCV even by second-generation assays. In this study we evaluated the performance of the new third-generation HCV assay (HCV 3.0) in 230 individuals with different second-generation anti-HCV (HCV 2.0) and HCV RNA patterns. Our results showed the followings: only one healthy adult had a discrepant result in 200 subjects negative (group I) or positive (group II) for HCV 2.0 and HCV RNA; 7 of 13 (54%) HCV 2.0-negative but HCV RNA-positive patients (group III) were HCV 3.0-positive; two of 17 (12%) so-called chronic non-B, non-C hepatitis patients (group IV) were positive for HCV 3.0. We conclude that third-generation anti-HCV assays are more sensitive and specific than second-generation assays in the detection of chronic HCV infection; however false-positive results may be observed among low-risk healthy persons.

Fibrosing cholestatic hepatitis in a hepatitis B surface antigen carrier after renal transplantation

A 45-year-old hepatitis B surface antigen carrier had an allograft kidney transplantation and maintenance immunosuppression with cyclosporin A and prednisolone. Six months later, she experienced a rapidly progressive hepatic failure manifested by elevation of serum bilirubin level, prolongation of prothrombin time, and mild to modest increase of serum aminotransferase levels. She died in 6 weeks. Postmortem liver histology showed canalicular and cellular cholestasis and ground-glass appearance and ballooning of most hepatocytes, but only mild inflammatory cell infiltration. Immunohistochemical staining showed massive loads of hepatitis B surface and core antigens in the hepatocytes and extensive periportal fibrosis. The whole picture was compatible with fibrosing cholestatic hepatitis described in hepatitis B virus-infected liver transplant. Sequencing of the hepatitis B virus genome amplified from the patient's serum indicated a precore mutant but few mutations in the core, pre-S, and S genes. Little inflammatory reaction was observed histologically despite HLA compatibility, a situation differing from that in liver transplant. This observation indicates that fibrosing cholestatic hepatitis may also occur in non-liver transplant setting.

Mixed infections of hepatitis C virus as a factor in acute exacerbations of chronic type C hepatitis

Twenty patients with chronic hepatitis C virus (HCV) infection and acute exacerbations (group A) were studied by polymerase chain reaction with genotype-specific primers to explore the role of mixed infections of HCV in acute exacerbations of chronic type C hepatitis. Another 26 patients who did not have acute exacerbation were matched controls (group B). Eleven (55%) of the group A patients had heterologous HCV, and their mean age was significantly younger than that of the 9 without heterologous infection (55 vs. 67 years, P < .05). In contrast, only 2 group B patients (7.7%) had heterologous HCV infection. In 10 of 13 patients with heterologous HCV infection, type III/2a virus emerged on type II/1b HCV, and viral interference was observed in half of them. The results support that mixed infections of HCV may be important in acute exacerbations of chronic type C hepatitis.

Intrafamilial transmission of hepatitis C virus

Family members of hepatitis C virus (HCV)-infected hemodialysis patients had a high rate (8.1%) of HCV infection and were often infected by the same genotype of HCV as the renal patients. Renal patients who had a longer history of hemodialysis or more frequent arteriovenous shunt replacement posed a higher risk to their household contacts, especially to their primary-care providers at home.

Packaging of hepatitis delta virus RNA via the RNA-binding domain of hepatitis delta antigens: different roles for the small and large delta antigens

Hepatitis delta virus (HDV) is composed of four specific components. The first component is envelope protein which contains hepatitis B surface antigens. The second and third components are nucleocapsid proteins, referred to as small and large hepatitis delta antigens (HDAgs). The final component is a single-stranded circular RNA molecule known as the viral genome. In order to study the mechanism of HDV RNA packaging, a four-plasmid cotransfection system in which each viral component was provided by a separate plasmid was employed. Virus-like particles released from Huh-7 cells receiving such a cotransfection were found to contain HDV RNA along with three proteins. Therefore, the four-plasmid cotransfection system could lead to successful HDV RNA packaging in vitro. The system was then used to show that the large HDAg alone was able to achieve a low level of HDV RNA packaging. Analysis of a variety of large HDAg mutants revealed that the RNA-binding domain was essential for viral RNA packaging. By increasing the incorporation of small HDAg into virus-like particles, we found a three- to fourfold enhancement of HDV RNA packaging. This effect was probably through a direct binding of HDV RNA, independent from that of large HDAg, with the small HDAg. The subsequent RNA-protein complex was packaged into particles. The results provided insight into the roles and functional domains of small and large HDAgs in HDV RNA packaging.

Inverse polymerase chain reaction for cloning cellular sequences adjacent to integrated hepatitis B virus DNA in hepatocellular carcinomas

Integration of hepatitis B virus (HBV) DNA is found in most HBV-related human hepatocellular carcinomas (HCCs). In the past, construction of genomic libraries was mainly employed to study the role of viral integration. However, large amounts of tissue DNA and a laborious screening procedures were required. Inverse polymerase chain reaction (IPCR) is based on the simple procedures of digestion of DNA with restriction enzymes and circularization of cleavage products before amplification using primers synthesized in the opposite orientations to those normally employed for PCR. This technique allows the in vitro amplification of DNA flanking a region of known sequence. By employing this method, starting from nanograms of hepatoma DNA, two adjacent cellular sequences were cloned from 11 HBV integrants in three HCCs. The original configurations in the chromosomes were further confirmed. One of the flanking cellular sequences was identified as the human 28S rRNA gene, the other was not found homologous to any known human sequences. This method appears to be practical and can be improved further to clone more flanking cellular sequences, especially in early and small HCCs.

Immune response to a hepatitis C virus nonstructural protein in chronic hepatitis C virus infection

The immune responses to a hepatitis C virus nonstructural protein (T3Ag) overlapping with the C100-3 antigen were examined in three groups of patients with chronic non-A, non-B hepatitis. Group I included 20 cases positive for both anti-C100-3 and the second-generation anti-HCV test (anti-HCV-II): Group II, five cases with anti-C100-3(-)/anti-HCV-II(+); and Group III, seven cases negative for both tests. HCV RNA was detectable in 20 (100%), 4 (80%) and 0 (0%) patients in each group, respectively. Proliferative responses of peripheral blood mononuclear cells to T3Ag were present in 16 (80%), 3 (60%) and 0 (0%) cases in each group, respectively (p < 0.05). Removal of CD8+ T cells from peripheral blood mononuclear cells resulted in a conversion of unresponsiveness to significant proliferation to T3Ag in the remaining cases in groups I and II, but not in group III. This change paralleled the antigen-induced production of interferon-gamma and interleukin-2, but not interleukin-4. The removal also enhanced the T3Ag-stimulated anti-C100-3 antibody production from cultured peripheral blood mononuclear cells in group II patients. These results indicate that the T3Ag-specific type 1 T helper cells play an important role in regulating anti-C100-3 antibody secretion in hepatitis C patients.

Long term clinical and virologic outcome of primary hepatitis C virus infection in children: a prospective study

To investigate the long term natural course of primary hepatitis C virus infection in children from the beginning, we prospectively followed up 88 children at risk because of frequent blood transfusions or of hepatitis C virus infection from the mother. Ten of the 88 children contracted primary infection during follow-up. In the acute stage of infection acute hepatitis with elevation of aminotransferases and a positive IgM antibody was found in both children infected during open heart surgery, 3 of the 5 multiply transfused children with congenital hemolytic anemia and none of the 3 infants infected by their mothers. Four of the 10 children later lost hepatitis C virus RNA, whereas 6 had a chronic course. Three of the latter 6 children had abnormal aminotransferase activities in the chronic phase. Our study suggests that the very young age of primary infection and the underlying status of the host may affect the clinical course of hepatitis C virus infection in children.

A clinicopathologic study of chronic non-A, non-B (type C) hepatitis in Taiwan: comparison between posttransfusion and sporadic patients

To elucidate the clinicopathological course and the role of hepatitis C virus in posttransfusion and sporadic chronic non-A, non-B hepatitis in Taiwan, we retrospectively studied 85 histologically confirmed patients with long-term follow up. Antibodies against hepatitis C virus (anti-HCV) by a second-generation assay were positive in 81% of the patients: 88% in the posttransfusion group and 76% in the sporadic group. Clinical manifestations were generally mild, and were noted in only half of the patients. During follow up, 33% (28 of 85 patients) had episodes of acute exacerbation of chronic liver disease and 24% (20 of 85) had normalized liver tests. Patients with normalized liver tests were usually anti-HCV negative (55% vs. 8%, p < 0.001). In 34 patients who had had blood transfusions, initial liver biopsies revealed chronic active hepatitis in 41%, active cirrhosis in 6%, and inactive cirrhosis in 9%. Follow-up biopsies in eight patients in this group showed histological progression in three after an average of 40.6 months. In the 51 sporadically infected patients, initial work-up revealed chronic active hepatitis in 37%, active cirrhosis in 4%, and inactive cirrhosis in 14%. Among the nine who underwent repeated biopsies, only one (11%) had progression. Patients above age 40 displayed more severe histologic activity than those below 40 (p < 0.005). Three patients, all with cirrhosis, died of hepatocellular carcinoma 7 to 12 years after follow up. Further genotyping study of hepatitis C virus in 28 patients showed that type II virus was most predominant in Taiwan and histologic severity was similar among patients infected with different genotypes.(ABSTRACT TRUNCATED AT 250 WORDS)

Frequent genetic alterations at the distal region of chromosome 1p in human hepatocellular carcinomas

Cytogenetic analysis of hepatocellular carcinoma (HCC) cell lines and primary HCC tissues has demonstrated chromosome 1p to be the region most commonly affected. To refine the altered locus, genetic abnormalities of this region were surveyed systemically by microsatellite polymorphism analysis. Twelve sets of primers evenly distributed on chromosome 1p which can amplify di- or tetranucleotide repeat length polymorphism by polymerase chain reaction were selected. The results were then supplemented by the conventional restriction fragment length polymorphism study. A comparison of the allele patterns between 30 pairs of HCC and their corresponding nontumor DNAs discovered chromosome 1p aberrations in 15 of 30 tumors (50%). The abnormalities can be classified into three groups. The first aberration was typical loss of heterozygosity that was found in 9 HCCs (30%). The second aberration was a 2-3-fold increase of allelic dosage, which was detected in 6 HCCs (20%). The third aberration was the novel microsatellite polymorphism, which was detected in 3 cases (10%). These abnormalities seemed to cluster at the distal part of chromosome 1p, with a common region mapped to 1p35-36, which is also the region with frequent loss of heterozygosity in neuroblastoma and colorectal and breast cancers. Therefore, loss of putative tumor suppressor gene(s) in this locus may participate in the development of hepatocellular carcinoma and a wide range of human cancers.

Transfusion-transmitted human T-cell lymphotropic virus type I infection in Taiwan: a true risk and occasional coinfection with hepatitis C virus shown in a prospective study

To study the incidence of human T-cell lymphotropic virus (HTLV) after blood transfusion in Taiwan, serum samples from 699 patients in a prospective study were examined for seroreactivity of anti-HTLV. By an enzyme immunoassay, 9 of the 699 recipients were repeatedly positive. Serial serum samples of these 9 patients were then confirmed with a Western blot analysis and with a polymerase chain reaction (PCR) assay for HTLV-I genome. Four were already positive for anti-HTLV before transfusion, 1 carried antibodies to HTLV-I transiently after transfusion, and only 4 cases had de nova seroconversions. These patients and their family members were called back and tested for HTLV-I genome in the peripheral blood mononuclear cell (PBMC) and plasma. All the serologically positive patients, except the "transient one," were positive for HTLV sequences in the PBMCs. Viral sequences could also be detected in several serum or plasma samples. In the family members, only the spouse of a pretransfusion-positive patient was infected. These results suggested that approximately 0.6% of the blood recipients were infected by HTLV-I through transfusion in Taiwan, and that the frequency of intrafamilial HTLV-I transmission is low. We also observed the unusual coinfection by both HTLV-I and hepatitis C virus in 2 patients, and superinfection of hepatitis C virus after blood transfusion in 1 HTLV-I carrier. Cases of coinfection suggest a prevalence of both viruses in blood donors and warrant further screening.

Age-specific prevalence of hepatitis B surface and e antigenemia in pregnant women in Taiwan

To investigate the age-specific prevalence of hepatitis B surface and e antigens (HBsAg and HBeAg) in pregnant women, we studied all the parturients encountered in National Taiwan University Hospital between 1985 and 1990. Serum HBsAg and HBeAg were checked by radioimmunoassay. The prevalence rate of HBsAg in pregnant women was 13.2%, 12.7%, 11.4%, 11.7%, 12.9% and 14.2%, respectively for each year. The figures seemed stable. The positive rate of HBeAg in HBsAg-positive pregnant women was 32.8%, 39.9%, 42.6%, 30.8%, 32.0% and 31.7%, respectively during the past 6 years. We also analyzed the results in different age-grouped pregnant women. The positive rate of HBsAg was 12.8%, 13.1%, 11.6% and 11.5% respectively in 21-25 year-old, 26-30 year-old, 31-35 year-old and 36-40 year-old groups. The positive rate of HBeAg in HBsAg-positive pregnant women was 49.4%, 36.5%, 31.5% and 20.0% respectively in these 4 age groups, with a prevalence declining with the advanced age. We conclude that HBsAg-positive rate was 11-14% in the pregnant women who visited our hospital, and their HBeAg-positive rate was 31-43%. No decrease of HBsAg carriage or HBeAg prevalence was seen in the past 6 years.

Posttransfusion hepatitis C virus infection in children

Hepatitis C virus (HCV) infection was investigated retrospectively and prospectively in children who had open heart surgery. The retrospective study included 196 patients who had open heart surgery 2 to 6 years before enrollment and were regularly followed. Antibody to HCV was detected in eight cases, and seven of these eight patients had viremia caused by HCV infection. The other patient's anti-HCV titer gradually decreased and HCV ribonucleic acid was absent throughout the course. Four of these eight had persistent viral replication without clinical evidence of hepatitis; the other three had viremia and chronic hepatitis. The HCV infection rate in the retrospective study group was about 4%. The HCV was of genotype 2 in five cases and of genotype 3 in two cases. The clinical outcome was not related to sex, age, amount of transfusion, or HCV genotype. For the prospective study, we enrolled 94 patients. Of the 56 enrolled after the initiation of anti-HCV screening in the blood bank, none was infected by HCV. Of the 94 patients, 38 were enrolled before screening; 4 had abnormal liver function 1 to 3 months after operation, and 2 were infected with HCV. One patient had an acute but resolving course; the other had persistent anti-HCV and HCV viremia, although the liver function test results returned to the normal range. The HCV in both cases belonged to genotype 2. We conclude that in Taiwan the seroconversion rate of HCV in children who underwent open heart surgery was 4% to 5%. Anti-HCV screening in donor blood significantly decreased the incidence of posttransfusion hepatitis C.

Temporal profile of hepatitis C virus antibody and genome in infants born to mothers infected with hepatitis C virus but without human immunodeficiency virus coinfection

To investigate mother-to-infant transmission of hepatitis C virus, serial follow-up of anti-HCV and hepatitis C virus RNA was undertaken in 11 infants born to hepatitis C virus-infected mothers who had been screened from 11,688 pregnant women. None of the hepatitis C virus-infected mothers was infected by human immunodeficiency virus. Anti-HCV was checked by the second-generation enzyme immunoassay kit, and hepatitis C virus RNA was examined by reverse transcriptase-nested polymerase chain reaction. Hepatitis C virus RNA was found in more than two serum samples in two of these 11 infants; those two infants were regarded as hepatitis C virus-infected. One of the two had hepatitis C virus RNA at the age of 1, 3, and 6 months, but not later. The course of hepatitis C virus RNA and anti-HCV in this baby may reflect fluctuating viral replication in chronic infectious disease or viral clearance in acute infection. The other infant had hepatitis C virus RNA detectable at the age of 3 months and at 15, 18 and 24 months. In the other nine non-hepatitis C virus-infected infants, maternally acquired anti-HCV gradually disappeared by the age of 6 months. The liver function profile fell to the normal range in all the infants, including the two hepatitis C virus-infected infants. This may indicate the subclinical nature of hepatitis C virus infection in infancy. Seven fathers and four siblings of these 11 infants were checked for anti-HCV and liver function tests; none had evidence of hepatitis C virus infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Possible role of high-titer maternal viremia in perinatal transmission of hepatitis C virus

To study perinatal transmission of hepatitis C virus (HCV), 15 anti-HCV-positive carrier mothers without human immunodeficiency virus coinfection were recruited. At delivery, maternal blood was taken and anti-HCV titer was determined and HCV RNA measured in each serum sample by reverse transcription polymerase chain reaction (PCR). A competitive PCR was used in selected samples to quantitate HCV concentration. The 15 neonates were followed regularly for 1 year and their sera were also assayed for anti-HCV and for HCV RNA by reverse transcription PCR. All the mothers were positive for HCV RNA. Only one normal spontaneously delivered neonate of a mother with extremely high titer of anti-HCV (1:20,000) and HCV concentration (10(10) copies/mL) had both anti-HCV and HCV RNA in serum for up to 6 months of age. In contrast, none of the remaining 14 neonates born to mothers with low- to high-titer anti-HCV (1:4-1:1000) and moderate amounts of HCV RNA (10(5)-10(6) copies/mL) contracted HCV infection. The results imply that high-titer maternal viremia and normal spontaneous delivery may allow more HCV to infect the neonate intrapartum, therefore establishing perinatal transmission.

Hepatitis C virus infection in pregnant women: detection by different anti-HCV immunoassays and serum HCV-RNA

To assess the seroepidemiology of hepatitis C virus (HCV) infection in pregnant women and explore the correlation between different anti-HCV immunoassays, we investigated 2 independent groups in Taipei: 1,687 pregnant women without screening for serum alanine aminotransferase (ALT) (group A) and 260 pregnant women with elevated ALT activity (> 45 IU/l) screened from 15,978 cases (group B). In group A, 11 women (0.65%) were found to be anti-HCV-positive by first-generation tests and 21 (1.24%) by second-generation tests, while 7 (2.69%) and 15 (5.77%) of the group B subjects were positive, respectively. The results of the second-generation assays, based either on recombinant proteins or synthetic peptides, were identical. Among the 36 second-generation anti-HCV-positive cases, 18 (86%) of the 21 cases in group A and 13 (87%) of the 15 cases in group B contained serum HCV-RNA by RT-PCR. We conclude that the prevalence of anti-HCV in pregnant Taiwanese women is 1.24%, and the prevalence is 5.77% among those with an elevated ALT level. HCV-RNA is present in 86% of the cases positive for anti-HCV. The discrepancy between positive anti-HCV and negative HCV-RNA in some pregnant women suggests that anti-HCV positivity in such cases may merely represent a past HCV infection or a fluctuating viremia.

Isoprenylation of large hepatitis delta antigen is necessary but not sufficient for hepatitis delta virus assembly

Hepatitis delta virus (HDV) encodes two proteins, the small hepatitis delta antigen (SHDAg) and large hepatitis delta antigen (LHDAg). Both proteins are identical except for the presence of additional 19 amino acids at the C terminus of LHDAg. While SHDAg is required for HDV RNA replication, LHDAg inhibits replication and is required together with hepatitis B surface antigen for the assembly of HDV. The C-terminal last 4 amino acids of LHDAg (Cys-Arg-Pro-Gln) is an isoprenylation motif. It has previously been shown that the mutation of the Cys inhibited the assembly of HDV. In order to discern whether this effect is due to change of amino acid residue or abolition of isoprenylation, we constructed several LHDAg mutants of the terminal three amino acid residues and tested their abilities to be packaged with HBsAg by cotransfection experiments. We also made GST-fusion proteins of these mutants and tested their abilities to be isoprenylated in rabbit reticulocyte lysate system. We found that some, but not all, of the substitutions of the amino acid residues other than the Cys also inhibited isoprenylation and that the status of isoprenylation of these mutant proteins correlated well with their abilities to be packaged with HBsAg into virions. This result indicates that isoprenylation, rather than the primary amino acid sequence, is required for LHDAg packaging. Furthermore, we found that the attachment of an isoprenylation motif to SHDAg did not enable it to be packaged with HBsAg and that the deletions of any 5 amino acids in the last 15 amino acids (amino acids 196 to 210) unique to the LHDAg abolished the packaging ability. In contrast, the deletion of 33 amino acids (amino acids 163 to 195) upstream of the last C-terminal 19 amino acids of LHDAg did not interfere with its packaging ability. Therefore, we conclude that the 15 amino acids upstream of the isoprenylation site of LHDAg are also essential for HDV assembly, and a large portion of the alleged C-terminal Pro/Gly-rich region (amino acids 146 to 195) is not required for the assembly process.

An analysis of substance abuse patterns, medical expenses and effectiveness of treatment in the workplace: long-term followup

This study of workplace substance abuse programs indicates that they are effective for many participants and also shows that these programs can significantly lower medical expenses for those who successfully complete them.

Hepatitis delta virus cDNA monomer can be used in transfection experiments to initiate viral RNA replication

The complementary DNA (cDNA) of hepatitis delta virus (HDV), constructed as tandem repeats under appropriate exogenous promoters, has been used to initiate viral replication in transfection experiments. Whether the structure of tandem repeats is essential has not yet been systematically examined. In this study, expression vectors containing only an HDV cDNA monomer, permutated at unique position of the genome, were shown still able to initiate viral replication. Furthermore, HDV cDNA monomer, separated from plasmid sequences by restriction enzyme digestion, also could be used to initiate viral RNA replication. The competence of HDV cDNA alone to direct viral RNA production suggested the presence of cryptic internal promoter-like elements. Such elements actually demonstrated by the chloramphenicol acetyltransferase assay. Therefore, HDV cDNA, in contrast to that of viroids, could be used to initiate viral RNA replication in monomeric form. This observation simplified the use of HDV cDNA for studying viral biology in transfection systems.

Hepatitis B virus in the colostra of HBeAg-positive carrier mothers

To investigate the amount of hepatitis B virus (HBV) in colostra of hepatitis B e antigen (HBeAg)-positive carrier mothers and the relationship of HBV amount between colostrum and maternal blood, 50 HBeAg-positive carrier mothers were recruited and studied for hepatitis B surface antigen (HBsAg) titer, HBeAg titer, and HBV-DNA concentration in their sera and colostra. According to the presence or absence of seral HBV-DNA determined by dot hybridization, these 50 HBeAg-positive carrier mothers could be divided into two groups: group 1 (n = 28, HBV-DNA < 0.04 ng/ml), and group 2 (n = 22, HBV-DNA > or = 0.04 ng/ml). The colostral HBsAg and HBeAg titers were both significantly higher in group 2 than in group 1. In addition, both colostral HBsAg and HBeAg titers had positive correlation with each corresponding maternal blood. Although the colostral HBV-DNA was undetectable by dot hybridization, all were positive by polymerase chain reaction with Southern blot hybridization. Because HBV-DNA can be detected in all HBeAg-positive carrier mother's milk, it reinforces the necessity of hepatitis B vaccination for the neonates born to these carrier mothers, particularly in countries with a high carrier rate.

Superinfection of heterologous hepatitis C virus in a patient with chronic type C hepatitis

A Taiwanese woman who had chronic infection of type II hepatitis C virus was superinfected by type III hepatitis C virus after blood transfusion. The subtypes of the hepatitis C virus were determined by direct sequencing of the envelope region of the viral genome in serial serum samples before and after transfusion. The original virus in the patient had a 95.6% homology to the Taiwanese isolate (a type II virus) by comparing nucleotide sequences of the envelope region. After transfusion, markedly elevated serum aminotransferase activities were noted and the virus sequenced showed only a 55.2% homology to the Taiwanese isolate but had a 88.9% homology to a Japanese isolate (a type III virus). After recovery from the acute episode, the newly introduced type III virus became undetectable and type II virus predominated again but with significant genetic variation in the follow-up samples as compared with the original type II virus. It was concluded that superinfection of hepatitis C virus indeed occurs in humans, and this should be taken into consideration in the pathogenesis of reactivation of chronic type C hepatitis.

Comparison of three different immunoassays and PCR for the detection of hepatitis C virus infection in pregnant women in Taiwan

To compare different hepatitis C virus (HCV) immunoassays and HCV-RNA in pregnant women, we investigated two independent groups: 1,687 cases without screening for serum alanine aminotransferase (ALT) (group A) and 333 cases with elevated ALT (> 45 IU/l) (group B), after screening 21,459 pregnant women. In group A, 11 (0.65%) and 21 (1.24%) were anti-HCV-positive by first- and second-generation tests, respectively, while in group B 8 (2.40%) and 19 (5.71%) were positive, respectively. The results revealed by second-generation assays based on either recombinant protein or synthetic peptides were identical, as were the anti-HCV titers in group B. Among 40 second-generation anti-HCV-positive cases, 18 (86%) of 21 in group A and 17 (89%) of the 19 in group B contained serum HCV-RNA by RT-PCR. Thus the prevalence of anti-HCV in Taiwanese pregnant women is 1.24% versus 5.71% in those with elevated ALT level.

Immunoglobulin M antibodies against hepatitis C virus antigens: significance and applications

The immunoglobulin M antibody against hepatitis C viral capsid (core) antigen has been found to be a possible marker for acute infection in post-transfusion hepatitis C. We extended this observation to a sporadic hepatitis C. In addition, a modified recombinant immunoblot assay (RIBA) that contained three HCV antigens (capsid, NS3 and NS5) in one strip was developed and used to study the antibody response among patients. This allowed a simultaneous comparison of either immunoglobulin M or G specific to individual HCV antigen and yielded more information. The assay was found useful in the diagnosis of acute hepatitis C in clinically uncertain cases.

Splicing mutations of the p53 gene in human hepatocellular carcinoma

Point mutations in exons of the tumor suppressor p53 gene occur frequently in many human tumors including hepatocellular carcinoma and are extensively studied. However, intronic point mutations are rare and are totally unknown for hepatocellular carcinoma. By reverse transcription and polymerase chain reaction amplification of p53 RNA from hepatocellular carcinoma tissues of 45 Taiwanese patients, we found amplified complementary DNA fragments of abnormal size in 4 (9%) tumor samples. Sequence analysis of these complementary DNA products revealed aberrant retention of intron 7 in one sample, insertion of 49 base pairs of the 3' end of intron 6 in 2 samples, and deletion of exon 4 in the other sample. Direct sequencing of their genomic DNA revealed relevant point mutations at consensus sequence at either the 5' or 3' splice site of intron 7, 6, 6, and 3, respectively. The splicing mutations produced p53 mutants with truncation of COOH-terminus that are identical to those found in lung cancers. Three of the 4 patients with splicing mutations were younger and had huge tumors. The results suggest a possible role of these p53 mutants in the development of human cancers.

Cytogenetic studies on human liver cancer cell lines

Karyotyping of human liver cancer cell lines and chromosome in situ hybridization of hepatitis B virus (HBV) DNA was performed in order to elucidate the possible mechanism of hepatocarcinogenesis from evidence of chromosomal changes and HBV integration patterns. HepG2-2 and HepG2-5 cell lines were HepG2 cells experimentally transfected with HBV DNA; the HCC36 cell line was derived from a hepatocellular carcinoma containing integrated HBV DNA from a Taiwanese patient. HepG2 cells, a hepatoblastoma cell line without HBV DNA integration, served as negative control. In HepG2-2, HepG2-5, and HCC36 cells, multiple integrations of HBV DNA were observed by in situ hybridization and hybridization signals occurred preferentially on certain chromosomes: 2, 5, 10, 11, 18; 7, 10, 13, 17, 18; and 4, 6, 11, 12q+, 18; respectively. In addition, a strong correlation between chromosomal changes and HBV integration was noticed in HCC36 cells, especially at chromosome 12q+.

The relationship between sleep apnea syndrome and hypothyroidism

To evaluate the prevalence of obstructive sleep apnea syndrome (OSAS) in patients with hypothyroidism, the prevalence of hypothyroidism in patients with OSAS, the possible factors predisposing to sleep-related breathing disorder in hypothyroid patients, and the effect of thyroid hormone in treating hypothyroidism associated with OSAS, we studied 65 patients with proven OSAS (apnea index [AI] > 5) and 20 hypothyroid patients. All patients were monitored for one overnight sleep study using polysomnography (Grass 78). We found only two (3.1 percent) of 65 OSAS patients had thyroid hypofunction. Of 20 patients with hypothyroidism, two showed moderate to severe OSAS and three had mild OSAS. Patients with both hypothyroidism and OSAS had impaired respiratory drive, but this was corrected by thyroid hormone therapy. Patients with hypothyroidism without OSAS were younger and had a lower percentage of ideal body weight than those with both hypothyroidism and OSAS. All hypothyroid patients were snorers. Thyroid hormone replacement was effective in correcting snoring only after one year of therapy. We conclude the following: (1) an overnight sleep study is not necessary in every case of hypothyroidism; (2) thyroid function studies need not be done routinely for every OSAS patient; (3) thyroid hormone therapy is effective for OSAS but it takes longer to correct the snore than respiratory drive; and (4) age and body weight are related to the development of OSAS.

Inactivation of the retinoblastoma gene in acute myelogenous leukaemia

To investigate the role of retinoblastoma susceptibility (RB) gene inactivation in leukaemogenesis, we evaluated 36 bone marrow specimens of acute leukaemia for RB protein expression by immunoprecipitation and Western blot analysis. 15 patients had no detectable RB protein at initial screening. However, nine of them were subsequently excluded due to evidence of protein degradation. Of 27 valid cases, six (22%) were repeatedly shown to lack expression of the RB protein with three different anti-RB antibodies. Five were patients with acute myelogenous leukaemia (AML) and one, mixed-lineage acute leukaemia. The RB inactivation was noted more frequently in AML (5/18, 28%) than in acute lymphoid leukaemia (0/7, 0%). By karyotyping, none of these six patients exhibited cytogenetic changes involving chromosome 13q14, the RB locus. There is no correlation between inactivation of the RB gene and FAB subtypes or cytogenetic changes. Four patients achieved complete remission with standard chemotherapy for 6, 12, 20 and 26+ months, respectively. Southern and Northern blot analyses further indicated that the RB genes were grossly intact and the level of RB transcripts did not decrease in the majority of these six patients. These results suggest that the absence of RB products in some of acute leukaemia might be regulated at the post-transcriptional level, and it imposes no significant effect on treatment response and prognosis.

Intrafamilial transmission of hepatitis C virus: the important role of infections between spouses

To investigate the intrafamilial transmission of hepatitis C virus (HCV) and related risk factors, anti-HCV antibodies in 186 family members of 48 index patients were studied. The index patients were anti-HCV-positive and had chronic liver disease. Overall, 10 family members (5.4%) were positive for anti-HCV, indicating a higher prevalence of anti-HCV among family members than among the Taiwanese general population. Spouses had the highest prevalence (21%) of anti-HCV, with older age and longer duration of marriage of index patients the most evident risk factors. HCV RNA, recovered from the infected couples by reverse transcription-nested polymerase chain reaction and subsequently sequenced directly, was identical at the nucleotide level in 3 of the 4 couples studied, and the remaining couple had a homology of greater than 96%. These results strongly support that interspousal transmission may be the most important route of intrafamilial spreading of HCV, and thus sexual transmission, although with low efficiency, should be considered important in HCV infection.

Transient immunoglobulin M antibody response to hepatitis C virus capsid antigen in posttransfusion hepatitis C: putative serological marker for acute viral infection

The development of serological assays for hepatitis C virus (HCV) has made specific diagnosis possible. However, markers useful in indicating acute-phase HCV infection have not been identified. By an immunoblotting method, we characterized the IgM and IgG antibody response against HCV capsid antigen in patients with HCV infection. Among 88% of patients with acute posttransfusion hepatitis C recruited in a prospective study, there was a transient IgM antibody response. The IgM antibody appeared shortly after onset of hepatitis (average 3.7 weeks), persisted for several months (average 18 weeks), and then disappeared. In contrast, the IgG antibody persisted long-term once it appeared. Among patients with chronic hepatitis C with milder disease activities (serum aminotransferase increase above normal levels of less than 4-fold), the IgM antibody was negative in the majority (72%). In those with acute exacerbations (aminotransferase increase of greater than 10-fold), about 55% were negative for the IgM antibody. The reactivity of the IgM antibody in the rest was weaker or became negative upon further dilution of serum. The results suggest that IgM anti-capsid antibody may serve as a marker indicating acute or active HCV infection.

Correlation between ELISA and recombinant immunoblot assay in serum samples positive for anti-HCV

To determine the false-positivity of antibody to hepatitis C virus (HCV) (anti-C100-3), the correlation between ELISA optical density (OD), anti-HCV titer and recombinant immunoblot assay (RIBA) in 87 anti-HCV-positive sera was analyzed. The results showed that > 90% of the serum samples with an anti-HCV OD > 2.0 or with titers > 10 x were RIBA reactive. These findings are applicable in daily clinical practice.

Functional study of hepatitis delta virus large antigen in packaging and replication inhibition: role of the amino-terminal leucine zipper

The large hepatitis delta antigen (HDAg) has been found to be essential for the assembly of the hepatitis delta virion. Furthermore, in a cotransfection experiment, the large HDAg itself, without the hepatitis delta virus (HDV) genome and small HDAg, could be packaged into hepatitis B surface antigen (HBsAg) particles. By deletion analysis, it was shown that the amino-terminal leucine zipper domain was dispensable for packaging. The large HDAg could also help in copackaging of the small HDAg into HBsAg particles without the need for HDV RNA. This process was probably mediated through direct interaction of the two HDAgs as a mutated large HDAg whose leucine zipper domain was deleted such that it could not help in copackaging of the small HDAg. This mutated large HDAg did not suppress HDV replication, suggesting that this effect is probably also via protein interaction. These results indicated that functional domains of the large HDAg responsible for packaging with HBsAg particles and for the trans-negative effect on HDV replication can be separated.

The Taiwanese hepatitis C virus genome: sequence determination and mapping the 5' termini of viral genomic and antigenomic RNA

The complete nucleotide sequence of hepatitis C virus (HCV) cloned from the liver tissue of a Taiwanese patient with post-transfusion type C hepatitis was determined. The 5' end of HCV genomic RNA was located 341 nucleotides upstream from the initiation codon for the viral polyprotein open reading frame. The 5' end of the viral antigenomic RNA was shown to have 13 consecutive As. Thus the 3' terminus of the viral genome is a stretch of U which ends about 50 nucleotides downstream from the stop codon of the large open reading frame. The nucleotide sequence homology between this HCV strain and two Japanese isolates was 90.5 and 90.7%, respectively. Homology with the United States strain, however, was only 77.8%. Accordingly, the indigenous Taiwanese HCV strain is of the same subtype as the Japanese isolates. Novel features of the viral genome termini are possibly relevant to HCV genome replication.

Cellular immune response to HBcAg in mother-to-infant transmission of hepatitis B virus

Cellular immunity to HBcAg was studied in hepatitis B virus carrier children and neonates born to hepatitis B virus carrier mothers. A significant proliferative response of peripheral blood mononuclear cells to HBcAg was found in 5 of 10 children with elevated ALT levels but in none of the nine HBeAg-positive children with normal ALT levels. HBeAg but not HBsAg was detected in cord blood of 9 of 10 neonates born to HBeAg-positive carrier mothers, suggesting exposure of these neonates to HBeAg in utero. However, cord mononuclear cells from neonates born to HBeAg-positive carrier mothers did not show a significant change in the proportion of suppressor and helper T-cell subsets or proliferative response to HBcAg. Nor did they produce interleukin-2 receptor after being cocultured with HBcAg. The unresponsiveness of peripheral-blood mononuclear cells or cord mononuclear cells to HBcAg was not reversed by CD8+ cell depletion. Although cord blood mononuclear cells from neonates born to carrier mothers positive for antibody to HBeAg also did not respond to HBcAg, we encountered an infant, born to a carrier mother positive for antibody to HBeAg, who contracted acute hepatitis B at 2.5 mo of age. The baby's peripheral-blood mononuclear cells showed a significant proliferative response to HBcAg. These results support the view that transplacental maternal HBeAg probably induces a specific unresponsiveness of helper T cells to HBcAg and HBeAg in the neonates born to HBeAg-positive carrier mothers. This specific helper T cell tolerance could be maintained throughout the early replicative phase of carrier state but might break someday with the appearance of raised ALT level.

[Changes in plasma interleukin-1 and their possible relationship with the changes in glucocorticoid receptor in aged long-distance runner]

For the study of the changes in plasma interleukin-1 (IL-1) and their possible relationship with the changes in glucocorticoid receptor (GR), plasma IL-1 and GR in peripheral blood leukocytes in aged long-distance runner were measured simultaneously. The activity of IL-1 was expressed as its ability to stimulate 3H-TdR incorporation in the thymocytes of C57 mice. GR was determined by whole cell assay with 3H-Dex. The results showed that the activity of plasma IL-1 in aged long-distance runner was 209%, 223% and 145% of the control at 14.7-18.7, 3.8-7.0 and 1.5-2.6 KD fractions. The GR in peripheral blood leukocytes in aged runner was 65% of the control. Possible relationship between the changes in IL-1 and GR in aged long-distance runner and its physiological significance are discussed.

Acute exacerbations of chronic type B hepatitis are accompanied by increased T cell responses to hepatitis B core and e antigens. Implications for hepatitis B e antigen seroconversion

T cell proliferative responses to hepatitis B virus-encoded envelope antigen (S + preS2 + preS1), recombinant core antigen (HBcAg), and natural hepatitis B e antigen (HBeAg) were examined in 22 HBeAg-positive patients with chronic type B hepatitis and 17 healthy hepatitis B surface antigen (HBsAg) carriers. The results showed that HBeAg-positive patients had (a) higher levels of T cell responses to HBcAg/HBeAg than those of healthy HBsAg carriers (P less than 0.001 and P less than 0.01, respectively); (b) a further increase in these T cell responses during acute exacerbations (P less than 0.05 and P less than 0.05, respectively); (c) subsidence in the T cell responses to HBcAg/HBeAg after recovery from acute exacerbations and HBeAg seroconversion, whereas the responses would persist at high levels if the patients did not enter a clinical remission; and (d) low levels of T cell responses to S + preS2 + preS1 either before or after HBeAg seroconversion. The appearance of increasing T cell responses to HBcAg/HBeAg usually occurred in the early phase of acute exacerbations. These findings imply that HBcAg/HBeAg-specific T cells play an important role in the exacerbations of chronic hepatitis B and in HBeAg seroconversion. HBcAg/HBeAg-specific precursor T cell frequencies were serially studied in selected cases by limiting dilution assay. Elevation (two- to fourfold) of HBcAg/HBeAg-specific precursor T cell frequencies contributed to the increase of HBcAg/HBeAg-specific T cell proliferation during acute exacerbations.

Temporal aspects of major viral transcript expression in Hep G2 cells transfected with cloned hepatitis B virus DNA: with emphasis on the X transcript

The major transcripts of hepatitis B virus (HBV) and the kinetics of their expression were studied in a transient expression system by transfecting partially duplicated copies of HBV genome into Hep G2 cells. By Northern blotting, six species of HBV-specific transcripts could be identified. They were the pregenomic (3.6 kb), the preS1 (2.6 kb), the preS2/S (2.2 kb), the X (0.8 kb), and two spliced (2.2 kb) RNAs, respectively. The preS2/S RNA and the spliced RNAs could be distinguished when a core gene-specific probe, which could not hybridize with the former, was used. Kinetic analysis of the expression of these RNAs revealed that the X transcript exhibited a pattern different from that of other viral transcripts. Amounts of all RNAs peaked at 24-48 hr post-transfection and then gradually declined. However, the X transcript became undetectable on Day 4 post-transfection while other viral RNAs persisted for at least 10 days. The unique expression profile of the X transcript suggested that it probably behaves as an early gene and this is consistent with its proposed role as a transactivator. Nevertheless, frameshift mutations within the X ORF had no obvious effects on the activities and temporal pattern of HBV transcription in this transient expression system.

Low prevalence of hepatitis C virus and infrequent perinatal or spouse infections in pregnant women in Taiwan

To assess the prevalence of hepatitis C virus (HCV) infection in the pregnant women in Taiwan, we investigated two groups of pregnant women, 944 women without serum alanine aminotransferase (ALT) screening (group A) and 197 women with abnormal ALT (greater than 45 IU/L) (group B). They were checked for anti-HCV (anti-C100-3) with HCV EIA kit (Abbott Lab., North Chicago, IL). The results showed that 21 (2.2%) in group A and 5 (2.5%) in group B were anti-HCV-positive. However, 15 out of 21 in group A had an optical density (O.D.) of anti-HCV less than 1.0, were negative by recombinant immunoblot assay (RIBA), and were regarded as false-positive. Nine infants delivered by those 11 cases were negative for anti-HCV at 6 months of age, while none of the 8 husbands were anti-HCV-positive. It is concluded that the prevalence of anti-HCV in pregnant women in Taiwan is low (6/944, 0.63%), even in the cases with abnormal ALT (5/197, 2.5%). There was no serologic evidence for perinatal transmission or spouse infection.

Small-form hepatitis B surface antigen is sufficient to help in the assembly of hepatitis delta virus-like particles

Hepatitis delta virus (HDV) has an envelope composed of large-, middle-, and small-form hepatitis B surface antigens (HBsAgs) provided by the helper hepatitis B virus (HBV). In order to examine the roles of individual HBsAgs in HDV assembly, we constructed plasmids containing each specific HBsAg gene and then cotransfected each plasmid with HDV cDNA into a permissive human hepatoma cell line (HuH-7) to examine the effects on HDV production. Results indicated that the plasmids containing only the HBsAg genes were able to complement HDV cDNA as efficiently as the plasmid containing the complete HBV genome in generating HDV-like particles. Moreover, the small-form HBsAg alone was sufficient for HDV packaging. The particles produced from the cotransfection experiments have density and protein composition characteristics similar to those of naturally occurring HDV. With the electron microscope, they were identified as 36- to 38-nm-diameter particles. It was concluded that only the HBsAgs were able to help in the assembly of HDV-like particles.

The large form of hepatitis delta antigen is crucial for assembly of hepatitis delta virus

The virions of hepatitis delta virus (HDV) contain two species of HDV-specific protein, a large and a small form of hepatitis delta antigen (HDAg). We examined the role of individual HDAgs in virion assembly in cotransfection experiments. First, we constructed a replication-competent HDV mutant expressing only the small HDAg. When cotransfected with a plasmid expressing hepatitis B virus surface antigens to the HuH-7 cells, the mutant did not produce HDV virions, whereas the wild-type HDV clone did. Therefore, though the small HDAg is important for viral replication and is incorporated into the virus, the small-form delta antigen by itself is insufficient for virion formation. When the system was co-transfected with an additional plasmid providing the large HDAg, the HDV virion was then recovered. There was also evidence suggesting that the large HDAg could be copackaged into the HBsAg particles, without the presence of the HDV genome and the small HDAg. The results indicate a crucial role of the large HDAg in HDV assembly.

An analysis of substance abuse patterns, medical expenses and effectiveness of treatment in the workplace

This article examines the effectiveness of substance abuse treatment offered by the Members Assistance Program of a self-insured union welfare fund. The authors find that medical costs decreased dramatically for participants who were under treatment for at least one year.

Hepatitis C virus infection in Taiwan

To investigate the epidemiology of HCV in Taiwan, anti-HCV was studied by radioimmunoassay or enzyme immunoassay in patients with chronic liver disease, healthy adults, and subjects at risk. The anti-HCV prevalence was 0.95% in 420 volunteer blood donors, 90% in 100 hemophiliacs and 81% in 58 parenteral drug abusers. Anti-HCV was present in 6 (7.7%) of 78 HBsAg-positive and 28 (65%) of 43 HBsAg-negative patients with chronic hepatitis, 3 (10%) of 31 HBsAg-positive and 13 (43%) of 30 HBsAg-negative cirrhotics, and 7 (17%) of 42 HBsAg-positive and 15 (63%) of 24 HBsAg-negative patients with HCC. An outbreak of non-A, non-B hepatitis revealed 18% of 57 patients to be positive for anti-HCV. In a prospective study of PTH, 37 or 13% patients contracted hepatitis and 22 (60%) were due to HCV, and at least 17 (77%) of them became chronic. Cloning of HCV genome in a Taiwanese patient with acute posttransfusion non-A, non-B hepatitis by using reverse transcription polymerase chain reaction was performed, and partial characterization of the nucleotide sequences showed 80% and 92% homology as compared to HCV sequences from Chiron and one of the published Japanese isolates, respectively. It is concluded that HCV infection plays a relatively minor role in HBsAg-positive liver decrease in Taiwan, but is strongly associated with HBsAg-negative chronic liver disease and HCC. It is also important in PTH, and the infection is extremely common in hemophiliacs and parenteral drug abusers. The Taiwanese strain of HCV seems more similar to that from Japan, as revealed by nucleotide sequences.

Isolation of a complementary DNA fragment of hepatitis C virus in Taiwan revealed significant sequence variations compared with other isolates

To clone and characterize hepatitis C virus strains present in Taiwan, RNA was extracted from liver tissue collected from a patient during the acute phase of posttransfusion non-A, non-B hepatitis. RNA was then subjected to complementary DNA synthesis and the polymerase chain reaction, using primers derived from the original nucleotide sequence of the United States hepatitis C virus strain. A complementary DNA clone, HCV-T3, containing 552 base pairs of hepatitis C virus complementary DNA sequences was isolated and characterized. The homologies in nucleotide sequence between the Taiwan isolate and either the United States or Japan isolate were 80.1% and 91.5%, respectively. However, most of the nucleotide changes occurred in the third base positions, resulting in much higher homologies in amino acid sequence of 91.8% and 97.3%, respectively. Amplification of the less conserved region of hepatitis C virus genome with the polymerase chain reaction was improved by use of primers with nucleotides matched to the local strain. Finally, in addition to the liver and serum, the viral genome was also demonstrated in the spleen tissue by similar methods, suggesting another possible target for hepatitis C viral infection. These findings indicate that there is considerable heterogeneity in hepatitis C virus genomes isolated from different areas of the world.

Prevalence of antibody to hepatitis C virus in pregnant Taiwanese

To assess the prevalence of an antibody to hepatitis C virus (anti-HCV) in pregnant women in Taiwan, and elucidate whether or not there is superinfection of the hepatitis B virus (HBV) in such cases, we investigated two independent groups of pregnant women. Group A included 294 without serum alanine aminotranferase (ALT) screening, and group B included 171 pregnant women with an abnormal ALT level (greater than 45 IU/L) who were recruited from 9,523 pregnant women screened for ALT. Blood samplings were taken at early gestation and each serum sample was tested with an HCV EIA kit for anti-HCV. The results showed that 1 woman in group A (0.34%) and 4 women in group B (2.3%) were anti-HCV-positive. However, all 5 cases showed positive antibodies to both the hepatitis B surface and core antigens, but were negative for the hepatitis B surface antigen. Therefore, the prevalence of anti-HCV in pregnant women by current assay in Taiwan is 0.34% without ALT screening, but increases to 2.3% among abnormal ALT cases. The prevalence rate is less than the rates reported in other countries. If confirmed by subsequent study, the results suggest that infection with HCV is low among healthy young females in Taiwan today.

Characterization and genetic analysis of alternatively spliced transcripts of hepatitis B virus in infected human liver tissues and transfected HepG2 cells

The transcriptional map of hepatitis B virus (HBV) has been expanded recently by the discovery of a singly spliced transcript in hepatoma cell lines transfected with cloned viral DNA and a doubly spliced one in naturally infected human liver tissues. By the use of reverse transcription and a subsequent polymerase chain reaction, the two spliced HBV RNAs were shown to be present in both types of cells. As further evidence, an HBV mutant was constructed and found to exclusively express the singly spliced RNA. This mutant was also used to quantitate the two spliced species in transfected HepG2 cells; they were found to be equally abundant, and each represented about 30% of the pregenomic RNA. The HBV mutant could still produce replication-competent HBV virions when transfected into HepG2 cells, indicating that the doubly spliced transcript, just like the singly spliced one, was not essential for HBV replication. However, the two abundant spliced HBV transcripts were detected in most naturally infected human liver tissues, suggesting that they may have biologic functions in vivo.