MarpolBase Expression: A Web-Based, Comprehensive Platform for Visualization and Analysis of Transcriptomes in the Liverwort Marchantia polymorpha

The liverwort Marchantia polymorpha is equipped with a wide range of molecular and genetic tools and resources that have led to its wide use to explore the evo-devo aspects of land plants. Although its diverse transcriptome data are rapidly accumulating, there is no extensive yet user-friendly tool to exploit such a compilation of data and to summarize results with the latest annotations. Here, we have developed a web-based suite of tools, MarpolBase Expression (MBEX, https://marchantia.info/mbex/), where users can visualize gene expression profiles, identify differentially expressed genes, perform co-expression and functional enrichment analyses and summarize their comprehensive output in various portable formats. Using oil body biogenesis as an example, we demonstrated that the results generated by MBEX were consistent with the published experimental evidence and also revealed a novel transcriptional network in this process. MBEX should facilitate the exploration and discovery of the genetic and functional networks behind various biological processes in M. polymorpha and promote our understanding of the evolution of land plants.

Squalomix: shark and ray genome analysis consortium and its data sharing platform

The taxon Elasmobranchii (sharks and rays) contains one of the long-established evolutionary lineages of vertebrates with a tantalizing collection of species occupying critical aquatic habitats. To overcome the current limitation in molecular resources, we launched the Squalomix Consortium in 2020 to promote a genome-wide array of molecular approaches, specifically targeting shark and ray species. Among the various bottlenecks in working with elasmobranchs are their elusiveness and low fecundity as well as the large and highly repetitive genomes. Their peculiar body fluid composition has also hindered the establishment of methods to perform routine cell culturing required for their karyotyping. In the Squalomix consortium, these obstacles are expected to be solved through a combination of in-house cytological techniques including karyotyping of cultured cells, chromatin preparation for Hi-C data acquisition, and high fidelity long-read sequencing. The resources and products obtained in this consortium, including genome and transcriptome sequences, a genome browser powered by JBrowse2 to visualize sequence alignments, and comprehensive matrices of gene expression profiles for selected species are accessible through https://github.com/Squalomix/info.

Identification of the sex-determining factor in the liverwort Marchantia polymorpha reveals unique evolution of sex chromosomes in a haploid system

Sex determination is a central process for sexual reproduction and is often regulated by a sex determinant encoded on a sex chromosome. Rules that govern the evolution of sex chromosomes via specialization and degeneration following the evolution of a sex determinant have been well studied in diploid organisms. However, distinct predictions apply to sex chromosomes in organisms where sex is determined in the haploid phase of the life cycle: both sex chromosomes, female U and male V, are expected to maintain their gene functions, even though both are non-recombining. This is in contrast to the X-Y (or Z-W) asymmetry and Y (W) chromosome degeneration in XY (ZW) systems of diploids. Here, we provide evidence that sex chromosomes diverged early during the evolution of haploid liverworts and identify the sex determinant on the Marchantia polymorpha U chromosome. This gene, Feminizer, encodes a member of the plant-specific BASIC PENTACYSTEINE transcription factor family. It triggers female differentiation via regulation of the autosomal sex-determining locus of FEMALE GAMETOPHYTE MYB and SUPPRESSOR OF FEMINIZATION. Phylogenetic analyses of Feminizer and other sex chromosome genes indicate dimorphic sex chromosomes had already been established 430 mya in the ancestral liverwort. Feminizer also plays a role in reproductive induction that is shared with its gametolog on the V chromosome, suggesting an ancestral function, distinct from sex determination, was retained by the gametologs. This implies ancestral functions can be preserved after the acquisition of a sex determination mechanism during the evolution of a dominant haploid sex chromosome system.

Clostridium zeae sp. nov., isolated from corn silage

A rod-shaped, Gram-stain-negative, strictly anaerobic, catalase-negative and endospore-forming bacterial strain CSC2^T was isolated from corn silage preserved in Tochigi, Japan. The strain CSC2^T grew at 15-40 °C, at pH 5.0-7.7 and with up to 0.5 % (w/v) NaCl. The main cellular fatty acids were C_14 : 0, C_16 : 0 and C_16 : 0 dimethyl acetal. The cellular polar lipids detected were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidic acid, lysophosphatidylethanolamine, phosphatidylserine, lysophosphatidylcholine and two unidentified polar lipids. Phylogenetic analysis of the 16S rRNA gene showed that strain CSC2^T was a member of the genus Clostridium and closely related to Clostridium polyendosporum DSM 57272^T (95.6 % gene sequence similarity) and Clostridium fallax ATCC 19400^T (95.3 %). The genomic DNA G+C content of strain CSC2^T was 31.1 mol% (whole genome analysis). The average nucleotide identity based on blast and digital DNA-DNA hybridization values between strain CSC2^T and the type strains of phylogenetically related species were below 71 and 24 %, respectively. On the basis of the genotypic, phenotypic and chemotaxonomic characteristics, it is proposed to designate strain CSC2^T as representing Clostridium zeae sp. nov. The type strain is CSC2^T (=MAFF212476^T=JCM 33766^T=DSM 111242^T).

Chromatin Organization in Early Land Plants Reveals an Ancestral Association between H3K27me3, Transposons, and Constitutive Heterochromatin

Genome packaging by nucleosomes is a hallmark of eukaryotes. Histones and the pathways that deposit, remove, and read histone modifications are deeply conserved. Yet, we lack information regarding chromatin landscapes in extant representatives of ancestors of the main groups of eukaryotes, and our knowledge of the evolution of chromatin-related processes is limited. We used the bryophyte Marchantia polymorpha, which diverged from vascular plants circa 400 mya, to obtain a whole chromosome genome assembly and explore the chromatin landscape and three-dimensional genome organization in an early diverging land plant lineage. Based on genomic profiles of ten chromatin marks, we conclude that the relationship between active marks and gene expression is conserved across land plants. In contrast, we observed distinctive features of transposons and other repetitive sequences in Marchantia compared with flowering plants. Silenced transposons and repeats did not accumulate around centromeres. Although a large fraction of constitutive heterochromatin was marked by H3K9 methylation as in flowering plants, a significant proportion of transposons were marked by H3K27me3, which is otherwise dedicated to the transcriptional repression of protein-coding genes in flowering plants. Chromatin compartmentalization analyses of Hi-C data revealed that repressed B compartments were densely decorated with H3K27me3 but not H3K9 or DNA methylation as reported in flowering plants. We conclude that, in early plants, H3K27me3 played an essential role in heterochromatin function, suggesting an ancestral role of this mark in transposon silencing.

Structural basis for replication origin unwinding by an initiator primase of plasmid ColE2-P9: duplex DNA unwinding by a single protein

Duplex DNA is generally unwound by protein oligomers prior to replication. The Rep protein of plasmid ColE2-P9 (34 kDa) is an essential initiator for plasmid DNA replication. This protein binds the replication origin (Ori) in a sequence-specific manner as a monomer and unwinds DNA. Here we present the crystal structure of the DNA-binding domain of Rep (E2Rep-DBD) in complex with Ori DNA. The structure unveils the basis for Ori-specific recognition by the E2Rep-DBD and also reveals that it unwinds DNA by the concerted actions of its three contiguous structural modules. The structure also shows that the functionally unknown PriCT domain, which forms a compact module, plays a central role in DNA unwinding. The conservation of the PriCT domain in the C termini of some archaeo-eukaryotic primases indicates that it probably plays a similar role in these proteins. Thus, this is the first report providing the structural basis for the functional importance of the conserved PriCT domain and also reveals a novel mechanism for DNA unwinding by a single protein.

Ctf4 coordinates the progression of helicase and DNA polymerase alpha

Ctf4 is a protein conserved in eukaryotes and a constituent of the replisome progression complex. It also plays a role in the establishment of sister chromatid cohesion. In our current study, we demonstrate that the replication checkpoint is activated in the absence of Ctf4, and that the interaction between the MCM helicase-go ichi ni san (GINS) complex and DNA polymerase alpha (Pol alpha)-primase is destabilized specifically in a ctf4Delta mutant. An in vitro interaction between GINS and DNA Pol alpha was also found to be mediated by Ctf4. The same interaction was not affected in the absence of the replication checkpoint mediators Tof1 or Mrc1. In ctf4Delta cells, DNA pol alpha became significantly unstable and was barely detectable at the replication forks in HU. In contrast, the quantities of helicase and DNA pol epsilon bound to replication forks were almost unchanged but their localizations were widely and abnormally dispersed in the mutant cells compared with wild type. These results lead us to propose that Ctf4 is a key connector between DNA helicase and Pol alpha and is required for the coordinated progression of the replisome.

The ColE2-P9 Rep protein binds to the origin DNA as a monomer

The Rep proteins of some plasmid replicons have two functions. Dimers bind to the operator sequences acting as auto-repressors, whereas monomers bind to the iterons to initiate replication of DNA. The ColE2 Rep proteins are present mostly in a dimeric form with some multimers larger than dimers in solution, while the form of Rep binding to Ori is not known. We used an EMSA-based method to determine the molecular weight of Rep in the Rep-Ori complex. The result suggested that Rep binds to Ori as a monomer. In addition, the result of EMSA using the Rep protein fused with the maltose binding protein and the His6-tag also supported this conclusion. We proposed that dimerization of Rep might probably be involved in keeping the copy number of the ColE2 plasmid at the normal low level by limiting the amount of active monomeric forms of Rep in the host cell.

Specific interaction between the initiator protein (Rep) and origin of plasmid ColE2-P9

The replication initiator protein (Rep) of plasmid ColE2-P9 (ColE2) is multifunctional. We are interested in how Rep binds to the origin (Ori) to perform various functions. We used the wild type and variants of Rep to study the Rep-Ori interaction by both in vitro and in vivo approaches, including biochemical analyses of protein-DNA interactions and an in vivo replication assay. We identified three regions (I, II, and III) of Rep, located in the C-terminal half, and three corresponding binding sites (I, II, and III) in Ori which are important for Rep-Ori interaction. We showed that region I, containing a putative helix-turn-helix motif, is necessary and sufficient for specific Ori recognition, interacting with site I of the origin DNA from the major groove. Region II interacts with site II of the origin DNA, from the adjacent minor groove in the left half of Ori, and region III interacts with site III, next to the template sequence for primer synthesis, which is one and one-half turn apart from site I on the opposite surface of the origin DNA. A putative linker region located between the two DNA binding domains (regions II and III) was identified, which might provide Rep an extended conformation suitable for binding to the two separate sites in Ori. Based on the results presented in this paper, we propose a model for Rep-Ori interaction in which Rep binds to Ori as a monomer.

The Rep protein binding elements of the plasmid ColE2-P9 replication origin

The plasmid ColE2-P9 (ColE2) origin (32bp) is specifically recognized by the plasmid-specified Rep protein that initiates DNA replication. The ColE2 origin is divided into at least three functional subregions (I, II, and III), and three sites (a, b, and c) found in subregions I and II play important roles in Rep protein binding. We performed SELEX experiments of plasmid ColE2 to determine the optimal sequences for specific binding of the Rep protein. From these experiments, we obtained a common 16-bp sequence (5'-TGAGACCANATAAGCC-3'), which corresponds to about one half of the minimal ColE2 origin and contains sites a and b. Gel mobility shift assays using single-point mutant origins and the Rep protein further indicated that high affinity sequence-specific recognition by the Rep protein requires sites a, b, and c, but that mutations in site c were less disruptive to this recognition than those in sites a and b.

Anatomy of the replication origin of plasmid ColE2-P9

The plasmid ColE2-P9 origin is a 32-bp region which is specifically recognized by the plasmid-specified Rep protein to initiate DNA replication. We analyzed the structural and functional organization of the ColE2 origin by using various derivatives carrying deletions and single-base-pair substitutions. The origin may be divided into three subregions: subregion I, which is important for stable binding of the Rep protein; subregion II, which is important for binding of the Rep protein and for initiation of DNA replication; and subregion III, which is important for DNA replication but apparently not for binding of the Rep protein. The Rep protein might recognize three specific DNA elements in subregions I and II. The relative transformation frequency of the autonomously replicating plasmids carrying deletions in subregion I is lower, and nevertheless the copy numbers of these plasmids in host bacteria are higher than those of the wild-type plasmid. Efficient and stable binding of the Rep protein to the origin might be important for the replication efficiency to be at the normal (low) level. Subregion II might be essential for interaction with the catalytic domain of the Rep protein for primer RNA synthesis. The 8-bp sequence across the border of subregions II and III, including the primer sequence, is conserved in the (putative) origins of many plasmids, the putative Rep proteins of which are related to the ColE2-P9 Rep protein. Subregion III might be required for a step that is necessary after Rep protein binding has taken place.

Whole genome association study of rheumatoid arthritis using 27 039 microsatellites

A major goal of current human genome-wide studies is to identify the genetic basis of complex disorders. However, the availability of an unbiased, reliable, cost efficient and comprehensive methodology to analyze the entire genome for complex disease association is still largely lacking or problematic. Therefore, we have developed a practical and efficient strategy for whole genome association studies of complex diseases by charting the human genome at 100 kb intervals using a collection of 27,039 microsatellites and the DNA pooling method in three successive genomic screens of independent case-control populations. The final step in our methodology consists of fine mapping of the candidate susceptible DNA regions by single nucleotide polymorphisms (SNPs) analysis. This approach was validated upon application to rheumatoid arthritis, a destructive joint disease affecting up to 1% of the population. A total of 47 candidate regions were identified. The top seven loci, withstanding the most stringent statistical tests, were dissected down to individual genes and/or SNPs on four chromosomes, including the previously known 6p21.3-encoded Major Histocompatibility Complex gene, HLA-DRB1. Hence, microsatellite-based genome-wide association analysis complemented by end stage SNP typing provides a new tool for genetic dissection of multifactorial pathologies including common diseases.

Novel algorithm for automated genotyping of microsatellites

Microsatellites or short tandem repeats (STRs) are abundant in the human genome with easily assayed polymorphisms, providing powerful genetic tools for mapping both Mendelian and complex traits. Microsatellite genotyping requires detection of the products of polymerase chain reaction (PCR) amplification by electrophoresis, and analysis of the peak data for discrimination of the true allele. A high-throughput genotyping approach requires computer-based automation at both the detection and analysis phases. In order to achieve this, complicated peak patterns from individual alleles must be interpreted in order to assign alleles. Previous methods consider limited types of noise peaks and cannot provide enough accuracy. By pattern recognition of various types of noise peaks, such as stutter peaks and additional peaks, we have achieved an overall average accuracy of 94% for allele calling in our actual data. Our algorithm is crucial for a high-throughput genotyping system for microsatellite markers by reducing manual editing and human errors.

Treatment of chronic hepatitis C patients with amantadine

BACKGROUND

Amantadine was reported to decrease serum alanine aminotransferase and HCV RNA levels in chronic hepatitis C patients who had not respond to interferon, but further experience has produced mixed results. The aim of this study was to investigate the efficacy and safety of amantadine in a larger number of patients with chronic hepatitis C.

METHODS

Fifty-eight consecutive patients with chronic hepatitis C were enrolled in this open-label prospective study. The patients had either received no antiviral agents or interferon therapy had previously failed.

RESULTS

In 85% of the patients, the time-relation between therapy and reduction of serum aminotransferase levels suggested a potential anti-inflammatory activity of the drug without an effect on viremia. Seven patients discontinued the therapy because of side effects, and overall, side effects were observed in 31% of patients.

CONCLUSIONS

Amantadine monotherapy in chronic hepatitis C patients may be effective in terms of reducing biochemical markers, but this effect was not associated with loss of viremia.

Long-term histological prognosis and serum fibrosis markers in chronic hepatitis C patients treated with interferon

BACKGROUND

Interferon (IFN) therapy is effective in 20-40% of patients with chronic hepatitis C, but the relationship between histological changes and the response to interferon is still unclear. We investigated the long-term histological prognosis and the changes of serum fibrosis markers after interferon therapy relation to the response.

METHODS AND RESULTS

One hundred and eighteen patients with chronic hepatitis C who received interferon therapy were divided into four groups based on the detection of viremia and the serum alanine aminotransferase (ALT) level after treatment. A histological examination was performed by using the histological activity index and the criteria of the METAVIR score. Serum fibrosis markers were used to measure the levels of hyaluronic acid and type IV collagen 7s. Responders, whose serum ALT levels became normal after treatment, demonstrated histological improvement. Histological improvement was more rapid in sustained virological responders with hepatitis C virus (HCV) RNA seronegativity than in biochemical responders with HCV-RNA seropositivity. Only sustained virological responders exhibited histological cure. In partial responders, whose serum ALT levels decreased to less than twice the upper of normal, and non-responders whose serum ALT levels were not reduced, liver fibrosis was unchanged or showed progression. Serum fibrosis markers increased with progression of the histological stage and varied depending on the response to interferon.

CONCLUSION

Normalization of serum ALT levels after interferon therapy led to a histological improvement, and that with viral clearance achieved histological cure. Serum fibrosis markers were useful indicators for long-term according to the response of IFN therapy.

Influence of TT virus infection on the thrombocytopenia of patients with chronic liver disease

TT virus (TTV) can replicate not only in the liver but also in hematopoietic cells. To investigate the possible influence of TTV infection on the hematological parameters of patients with chronic liver disease, serum samples from 581 patients with chronic, viral or non-viral liver disease were tested for TTV DNA by polymerase chain reaction (PCR). PCR was performed by two distinct methods using N22 primer pairs (N22 PCR), which detect primarily the four major TTV genotypes (1-4), and using genotype 1-specific primers (Genotype 1-PCR). Thirteen hematological parameters measured in routine laboratory tests were compared among the patients who were positive or negative for TTV infection. The platelet count was significantly lower in the N22 PCR-positive group than in the N22 PCR-negative group among the 189 patients with chronic hepatitis C (CH-C) and among the 40 patients with chronic hepatitis without serological markers of ongoing hepatitis B virus or hepatitis C virus infection (CH-NBNC) (P<0.0001, P<0.005, respectively). Similarly, among the patients with CH-C or CH-NBNC, the platelet count was significantly lower in the TTV genotype 1-positive group than in the TTV genotype 1-negative group (P<0.001, P<0.05, respectively). The reduced platelet count of the TTV DNA-positive group was observed in every fibrotic stage of chronic hepatitis (F0-F3). These results suggest that infection of TTV of certain genotypes including genotype 1 may worsen the thrombocytopenia of patients with CH-C or CH-NBNC, irrespective of the degree of hepatic fibrosis.

Influence of TT virus on the histopathological features of nonalcoholic fatty liver disease

The sera of 38 patients with nonalcoholic fatty liver disease (NAFLD) including nonalcoholic steatohepatitis (NASH), were tested for TT virus (TTV) DNA by polymerase chain reaction (PCR) using three different primer pairs (UTR PCR, N22 PCR and genotype-1 PCR), and various histological features of the liver biopsy specimens were compared among those who were positive or negative for TTV infection. By UTR PCR which detects all TTV genotypes, TTV DNA was detected in 37 (97%) of the 38 patients. In contrast, N22 PCR which detects primarily TTV genotypes 1-4, detected TTV DNA in 18 patients (47%). In the liver biopsy specimens, moderate to many acidophilic bodies, moderate to marked focal/spotty necrosis of hepatocytes and marked stellate, pericellular or perivenular fibrosis were observed significantly more frequently among those who were positive for TTV DNA by N22 PCR, than among those who were negative by N22 PCR. Twelve patients (32%) were positive for TTV genotype 1. Moderate to marked vacuolation of nuclei, moderate to many acidophilic bodies, and moderate to marked focal/spotty necrosis as well as marked stellate, pericellular or perivenular fibrosis were found significantly more frequently in the TTV genotype 1-positive group than in the TTV genotype 1-negative group. These results suggest that certain TTV genotypes including genotype 1 influence the necrosis and inflammation of hepatocytes and liver fibrosis in NAFLD patients.

Does the control of alanine aminotransferase levels lead to a regression of liver fibrosis in chronic hepatitis C patients?

The aim of this study was to investigate the effect of various medications other than interferon (IFN) on liver fibrosis in chronic hepatitis C (CH-C) patients, and the results were compared with those obtained in CH-C patients without therapy. Fifty CH-C patients (32 men and 18 women; mean age 58.5 years) without previous IFN therapy, who randomly received medicines other than IFN such as Stronger Neo-Minophagen C, Ursodeoxycholic acid and a herbal medicine, Sho-saiko-to (TJ-9) (Group I), and as a control group, 45 CH-C patients (27 men and 18 women; mean age 56.6 years) without therapy (Group II) were examined. All patients had persistent alanine aminotransferase (ALT) elevation more than 6 months before this study and were also subdivided into three subgroups according to different pattern of ALT during the observation period, i.e. (a): persistently ALT<60 IU/l (below about twice the upper limit of normal range); (b): persistently ALT>/=60 IU/l; and (c) other than (a) and (b). All patients were biopsied twice before starting this study and during observation period and the liver fibrosis was compared between them by staging in each case. When the fibrosis stage was the same between two specimens, we determined whether the degree of fibrosis had improved or worsened by computed image analysis. Blood tests for fibrosis marker, serum aminoterminal peptide of type III procollagen (P III P) and liver enzyme such as albumin (Alb) and zinc turbidity test (ZTT) levels, and platelet (Plt) counts were also examined on the two times of liver biopsy. As a result, there were no significant differences in fibrotic improvement rate when assessed by both staging only and staging together with fibrotic ratio, determined by computed image analysis and also in yearly change of P III P (P/Y) and fibrosis (F/Y), the changed rate of Alb, ZTT levels and Plt counts between Group I and Group II, except for P/Y in subgroup (a) which was rather higher in Group I than in Group II. There were also no significant relationship between the changes of histological activity and fibrosis staging in both groups. In conclusion, other medications than IFN could not significantly improve both liver fibrosis and its associated laboratory data irrespective of ALT levels in CH-C patients as compared to the control group during average 3 years' follow-up period.

Influence of TT virus on the clinical course of alcoholic liver disease

The sera of 43 patients with alcoholic liver disease (ALD) who abstained from alcohol for 4 weeks, were tested for TT virus (TTV) DNA by polymerase chain reaction (PCR) using three different primer pairs (UTR PCR, N22 PCR and genotype-1 PCR). The clinical course of the TTV DNA-positive and -negative groups was compared. By UTR PCR which detects all TTV genotypes, TTV DNA was detected in 40 patients (93%). N22 PCR which detects primarily TTV genotypes 1-6, detected TTV DNA in 17 patients (40%). The alanine aminotransferase (ALT) level 4 weeks after the start of abstinence was significantly higher and the rate of change in ALT {[(ALT on admission-ALT 4 weeks after abstinence)/(ALT on admission)]x100} was lower in the patients who were positive by N22 PCR, than in those who were negative by N22 PCR. Twelve patients (28%) were positive for TTV genotype 1. In the TTV genotype 1-positive group, the ALT 4 weeks after the start of abstinence was significantly higher, and the improvement rates of ALT, gamma-glutamyl transpeptidase and alkaline phosphatase levels were lower than those in the TTV genotype 1-negative group. These results suggest that certain genotypes of TTV may interfere with the improvement of liver function following the start of abstinence in ALD patients.

Changes of liver fibrosis in chronic hepatitis C patients with no response to interferon-alpha therapy: including quantitative assessment by a morphometric method

The aim of this study was to evaluate the antifibrotic effect of interferon (IFN)-alpha in chronic hepatitis C (CH-C) patients with no response to IFN-alpha therapy. We studied 76 patients (46 men, 30 women; mean age, 55.6 years) who received IFN-alpha intramuscularly, at a total close of 480 to 880MU for 6 months (group A). As a control group, we studied 50 patients (32 men and 18 women; mean age, 58.5 years) with CH-C who received medication other than IFN (ie, Strong-Neo-Minophagen C, ursodeoxycholic acid, and a herbal medicine, Sho-saiko-to [TJ-9]) and who had persistent alanine aminotransferase (ALT) elevation (group B). All patients were subdivided into three subgroups according to different patterns of ALT changes during the observation period, ie, (a) persistent ALT level < 60IU/ 1 (below about twice the upper limit of the normal range), (b) persistent ALT level > or = 60IU/1, (c) ALT levels other than (a) and (b). Liver biopsy was performed within 6 months prior to IFN therapy and more than 6 months after IFN therapy, while two liver biopsies were performed during therapy in group B. Liver fibrosis was compared between two specimens by staging. When the fibrosis stage was the same in the two specimens, we determined whether the fibrosis had improved or worsened by comparing the fibrotic ratio, ie, the ratio of the area of fibrosis to the area of the entire liver tissue specimen, calculated using computed graphic software. Serum aminoterminal peptide of type III procollagen (PIIIP) levels were measured on the day of the liver biopsy and their mean yearly changes were compared between the two groups. Improvement of liver fibrosis was found in 12% to 30% of patients in each ALT subgroup and in 24% of all patients in group A and there were no significant differences in liver fibrosis in comparison with findings in of group B when assessed by staging alone. However, these percentages rose to 59% to 75% and 66%, respectively, when liver fibrosis was assessed by the fibrotic ratio together with staging, resulting in a significant difference in fibrosis between groups A and B in total (P < 0.01). The mean yearly changes in serum PIIIP levels in each subgroup and in all patients in group A were below zero, indicating a tendency to improvement of fibrosis after IFN therapy, while these changes in group B were all above zero, except for subgroup (c). Improvement of fibrosis after IFN therapy was found in 15 of 24 patients (64%) whose ALT changes had the same pattern before and after IFN therapy, although no significant difference was noted between improved and worsened patients. These results suggest that IFN-alpha may have an antifibrotic effect even in CH-C patients with no overt response to IFN-alpha therapy, compared with the effect of medications other than IFN.

Interferon treatment in patients with chronic hepatitis C with normal alanine-aminotransferase activity

BACKGROUND/AIMS

Chronic hepatitis C virus carriers may have repeatedly normal alanine aminotransferase activity despite detectable viremia and histological hepatitis. We aimed to evaluate the effect of interferon treatment in these cases.

METHODOLOGY

Twelve patients with persistently normal alanine aminotransferase levels at least 6 months before therapy were treated with recombinant interferon (IFN)alpha-2b for 6 months, totaling 840 MU in amount. Alanine aminotransferase levels were measured monthly during treatment and after treatment withdrawal, and HCV-RNA levels were measured by polymerase chain reaction before treatment, and 6 and 12 months after treatment withdrawal.

RESULTS

At treatment withdrawal, HCV-RNA levels had significantly decreased and HCV-RNA disappeared in 9 of the 12 patients by polymerase chain reaction. At 6 months after treatment withdrawal, HCV-RNA reappeared in 6 of the 9 patients whose HCV-RNA was negative at treatment withdrawal. Over all, only 4 of the 12 patients (33%) were sustained virological responders (HCV-RNA is negative more than 6 months after treatment withdrawal). Pre-treatment HCV-RNA levels in a sustained virological responder was significantly lower than that of transient and non-responders (4.9 +/- 1.6 vs. 7.7 +/- 1.6 log10[copies/ml], p < 0.05). Of 8 patients who did not achieved sustained virological response, alanine aminotransferase levels had transiently increased above normal during treatment in one patient and after treatment withdrawal in 6 patients; however, in the remaining one patient abnormal values have continued from 8 months after treatment withdrawal till now for 24 months.

CONCLUSIONS

In patients with chronic hepatitis C with normal alanine aminotransferase levels, the response to interferon therapy was by no means satisfactory. However, if it would be used in cases with the lower pre-treatment HCV-RNA levels with careful attention to a transient alanine aminotransferase elevation, the more a sustained virological response might be expected.

[Comparative studies on immunogenicity of Chinese hamster ovary cell drived HB vaccine and plasma drived HB vaccine]

Chinese Hamster Ovary cell drived HB vaccine (CDV) and plasma drived HB vaccine (PDV) were separately given to two groups of 113 and 112 medical staff subjected, and the anti-HBs responses were observed for five years from the initial injection. The anti-HBs positive rate at 7 months was 96.9% (mean geometric anti-HBs concentration 588 IU/L) in CDV group and 77.8% (83 IU/L) in PDV group, and the positive rate and mean titer of anti-HBs were always higher for 5 years in CDV group. Those differences were remarkable in the subjects aged over 40 years. The decreasing curves of anti-HBs titer in the two groups were parallel from 7th. month to 60th. month. Thus, the protective efficacy was estimated to be far longer in CDV than PDV. Also, the rate of non-responder was less lower in CDV group (2.8%) than PDV group (15.2%). Above results show that CDV has a higher immunogenicity than PDV.

[Diagnosis and treatment of pulmonary tuberculosis complicated with chronic liver disease]

Immunocompromised or malnutritional hosts are high risk group of pulmonary tuberculosis. Chronic liver disease especially decompensated cirrhosis of the liver is one of the risk group for this infection. When ascites or pleural effusion developed in patient with hepatic cirrhosis, complication of pulmonary tuberculosis must be considered. In such condition, drug metabolism was impaired so that anti-tuberculous drugs should be used carefully, but in almost cases except decompensated cirrhotic patients are tolerable for standard anti-tuberculous combination therapy and they could be cured. Hepatitis C virus infection is common in patients with old pulmonary tuberculosis because many of them were infected Hepatitis C virus at the time of blood transfusion for pulmonary resection or thoracoplasty. In such condition recurrence of pulmonary tuberculosis is rare but probability of recurrence must be considered when they developed decompensated cirrhosis.

[Comparative studies on immunogenicity of Chinese hamster ovary cell derived HB vaccine and plasma derived HB vaccine]

Chinese Hamster Ovary Cell derived HB vaccine (CDV) and plasma derived HB vaccine (PDV) were separately given to two groups of 131 and 112 medical stuff subjected, and both the anti-HBs responses were observed for 24 months from the time of first injection. The anti-HBs positive rate at the 7th month was 97% (mean geometric anti-HBs concentration 588 IU/L) in CDV group and 78% (83 IV/L) in PDV group, and the positive rate and mean titer of anti-HBs were always higher for 24 months in CDV group. The differences were remarkable between both the subjects aged over 40 years. The decreasing curves of the anti-HBs titer in the two groups were almost parallel; accordingly, the protective efficacy was estimated to be far longer in CDV. Also, the rate of non-responder was less lower (2.8%) in CDV group than that (15.2%) in PDV group. Above results show that CDV has a higher immunogenicity than PDV.

Usefulness of percutaneous transluminal angioplasty for aortitis syndrome

A woman with aortitis syndrome who had had severe hypertension for more than 30 years, despite the administration of various antihypertensive drugs, underwent percutaneous transluminal angioplasty (PTA) a total of three times. The operation resulted in good control of BP and with an improvement of other hemodynamics without any medication for one year after PTA.

[99mTc-MAA brain scan and CT in the diagnosis of intracranial diseases (author's transl)]

Brain scan with 99mTc-labelled macroaggregated albumin (MAA brain scan) and computed tomography studies (CT) were performed on 78 patients with intracranial diseases. 99mTc-MAA was injected into right and left carotid artery respectively, at the different time. And then diagnostic evaluation of both techniques were investigated. The MAA brain scan was useful for the detection of ischemic lesion in the early stage after onset of cerebral infarction. It was shown in 29.5% that partial field of anterior cerebral artery was injected through the contralateral artery. In these cases, the MAA brain scan was also useful. In the cases of hemorrhagic lesions, however, the CT was more useful than MAA brain scan. Therefore, the both techniques helped each other in the diagnosis of intracranial diseases.

[Diagnostic evaluation on cerebral hemisphere scintigraphy using 99mTc-MAA (author's transl)]

Using 99mTc-labeled macroaggregated albumin (99mTc-MAA), we made an examination of the cerebral blood flow distribution with various kinds of cerebrovascular diseases in 151 cases. The particle size of MAA used in this study ranged from 10 to 100 micron. Scan was performed after injection of 3 mCi of 99mTc-MAA into common carotid artery. No side effects were observed except for one case with headache. Distribution of 99mTc-MAA was found to be homogeneous in normal cerebral hemisphere but not in the lesion. Most lesion was shown as nonradioactive area. Meningioma with hypervascularity was represented as hot area. By this method cerebral infarct could be easily represented not only in main artery but also in such a very small artery as hardly detected by CAG. This method is therefore useful for detecting cerebral infarct, sequela of cerebral apoplexy, head injury and others. The dose of 99mTc-MAA used in this method is much lower compared with those of common brain scan, its excretion is speedy, and therefore internal radiation exposure is diminished.