Dynamics of Microbial Community during the Co-Composting of Swine and Poultry Manure with Spent Mushroom Substrates at an Industrial Scale

Spent mushroom substrates (SMSs) can be developed as a biofertilizer through composting. Here, we investigated the dynamics of bacterial and fungal communities during commercial composting and the effect of swine and poultry manure on their communities through MiSeq pyrosequencing. Weissella paramesenteroides and Lactobacillus helveticus were dominant bacterial species in the composts with soy waste (SMS-SW), whereas Thermotogaceae sp. and Ureibacillus sp. were dominant in the composts with swine and poultry manure (SMS-PM). For the fungal community, Flammulina velutipes was dominant in SMS-SW, whereas Trichosporon asahii, Candida catenulate, Aspergillus fumigatus, and Candida tropicalis were dominant in SMS-PM. The addition of manure affected the bacterial community significantly. Redundancy analysis indicated that bacterial communities were affected by temperature, potassium, and potassium oxide and fungal communities by temperature, Kjeldahl nitrogen, organic matter, and ammonium nitrogen. Our findings can guide future research on composting microbiology.

Undescribed alkyne-geranylcyclohexenetriols from the endophyte Diaporthe caulivora 09F0132 and their anti-melanogenic activity

To explore valuable endophytic fungus from Formosan Lauraceous plants as natural medicinal products, the fungus, Diaporthe caulivora isolated from leaves of Neolitsea daibuensis, was investigated. Through a thorough investigation of the ethanolic extract of the solid fermentation of D. caulivora 09F0132, six undescribed alkyne-geranylcyclohexenetriols, caulivotrioloxins A-F, one undescribed trichopyrone, diapopyrone, two undescribed sesquiterpenes, caulibysins A-B, one compound firstly isolated from the natural source, 3-O-desmethyl phomentrioloxin, and eight known compounds have been successfully identified. The absolute configuration of caulibysin A was confirmed by single-crystal X-ray diffraction, and those of (3R,8S)-5,7-dihydroxy-3-(1-hydroxyethyl)phthalide and (3S,8S)-5,7-dihydroxy-3-(1-hydroxyethyl)phthalide were determined by circular dichroism (CD) spectra. Among the isolated compounds, caulivotrioloxin A concentration-dependently decreased the cellular melanin contents and tyrosinase activities in mouse melanoma B16-F10 cells, suggesting the anti-melanogenic potentials. The anti-melanogenic effects of caulivotrioloxin A involved the decrease in the protein expressions of melanogenic enzymes, including tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2. Taken together, these results suggested that the isolates from D. caulivora could be served as natural melanogenesis inhibitors for cosmeceutical applications.

AR-12 Has a Bactericidal Activity and a Synergistic Effect with Gentamicin against Group A Streptococcus

Streptococcus pyogenes (group A Streptococcus (GAS) is an important human pathogen that can cause severe invasive infection, such as necrotizing fasciitis and streptococcal toxic shock syndrome. The mortality rate of streptococcal toxic shock syndrome ranges from 20% to 50% in spite of antibiotics administration. AR-12, a pyrazole derivative, has been reported to inhibit the infection of viruses, intracellular bacteria, and fungi. In this report, we evaluated the bactericidal activities and mechanisms of AR-12 on GAS infection. Our in vitro results showed that AR-12 dose-dependently reduced the GAS growth, and 2.5 μg/mL of AR-12 significantly killed GAS within 2 h. AR-12 caused a remarkable reduction in nucleic acid and protein content of GAS. The expression of heat shock protein DnaK and streptococcal exotoxins was also inhibited by AR-12. Surveys of the GAS architecture by scanning electron microscopy revealed that AR-12-treated GAS displayed incomplete septa and micro-spherical structures protruding out of cell walls. Moreover, the combination of AR-12 and gentamicin had a synergistic antibacterial activity against GAS replication for both in vitro and in vivo infection. Taken together, these novel findings obtained in this study may provide a new therapeutic strategy for invasive GAS infection.

Prevotella hominis sp. nov., isolated from human faeces

A strictly anaerobic predominant bacterium, designated as strain gm001^T, was isolated from a freshly voided faecal sample collected from a healthy Taiwanese adult. Cells were Gram-stain-negative rods, non-motile and non-spore-forming. Strain gm001^T was identified as a member of the genus Prevotella, and a comparison of 16S rRNA and hsp60 gene sequences revealed sequence similarities of 98.5 and 93.3 %, respectively, demonstrating that it was most closely related to the type strain of Prevotella copri. Phylogenomic tree analysis indicated that the gm001^T cluster is an independent lineage of P. copri DSM 18205^T. The average nucleotide identity, digital DNA‒DNA hybridization and average amino acid identity values between strain gm001^T and P. copri DSM 18205^T were 80.9, 28.6 and 83.8 %, respectively, which were clearly lower than the species delineation thresholds. The species-specific genes of this novel species were also identified on the basis of pan-genomic analysis. The predominant menaquinones were MK-11 and MK-12, and the predominant fatty acids were anteiso-C_15 : 0, C_15 : 0 and iso-C_15 : 0. Acetate and succinate were produced from glucose as metabolic end products. Taken together, the results indicate that strain gm001^T represents a novel species of the genus Prevotella, for which the name Prevotella hominis sp. nov. is proposed. The type strain is gm001^T (=BCRC 81118^T=JCM 33280^T).

Salinity, pH and temperature growth ranges of Halophytophthora isolates suggest their physiological adaptations to mangrove environments

Species of Halophytophthora are early colonisers of fallen mangrove leaves in the tropics but recently found commonly in temperate areas. In mangrove habitats, temperature and salinity change rapidly daily (high/low tide) and seasonally (summer/winter, rainy/dry seasons). Mangrove organisms have to develop adaptive strategies to thrive in such a physiologically challenging environment. In this study, growth of three isolates of Halophytophthora avicenniae and two isolates of H. batemanensis was tested under combined effects of 3 temperatures (15°C, 25°C, 37°C), 3 pHs (6, 7, 8) and 4 salinities (4 ‰, 8 ‰, 16 ‰, 32 ‰). No/little growth was observed at 37°C and growth saturation occurred earlier at 25°C than at 15°C. The log phase of growth was steeper at pH 6 than pH 7 and 8. Temperature and pH were found to exert a greater effect on growth than salinity. Generally, a reduction of growth rate was observed at pH 8 and 15°C. Increase in salinity caused a slight decrease in growth, most noticeable at 32 ‰. The wide growth ranges of temperature, salinity and pH of Halophytophthora isolates suggest that they are well adapted to the physical and chemical conditions of mangrove habitats.

Isolation and Structure Elucidation of Secondary Metabolites From an Endophytic Fungus Annulohypoxylon ilanense

Fractionation of the EtOAc-soluble fraction of the liquid fermentation of an endophytic fungus Annulohypoxylon ilanense associated with the wood of medicinal plant Cinnamomum species resulted in the isolation of 1 new α-pyrone, ilanpyrone (1), along with 3 previously identified compounds, 2 to 4. Their structures were elucidated by means of spectroscopic and mass-spectrometric analyses, especially 1D and 2D nuclear magnetic resonance (NMR) spectroscopy as well as high-resolution electrospray ionization mass spectrometry. The isolated compounds were tested for their cytotoxicity against MCF-7, NCI-H460, and SF-268 cell lines using the MTT assay. Among them, compounds 1 and 4 were found to have moderate-to-weak cytotoxic effects against these 3 cell lines in vitro.

Saccharomonospora piscinae sp. nov., a novel actinobacterium from fishpond sediment in Taiwan

Strain 06168H-1^T was isolated from a fishpond sediment sample collected from the southern area of Taiwan, and a polyphasic approach was used to determine its taxonomic position. The isolate grew between 20-40 °C and 0-8 % (w/v) NaCl. It produced branched and unfragmented substrate mycelia. Short spore chains (3-10 spores per chain) formed on branched aerial mycelia. The spore chains contained non-motile, smooth-surfaced, oval spores. Galactose, arabinose and ribose were the whole-cell sugars and meso-diaminopimelic acid was present in its peptidoglycan. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, phosphatidylcholine, hydroxyphosphati dylethanolamine and a ninhydrin-positive phosphoglycolipid. The predominant menaquinone was MK-9(H4) and minor components were MK-8(H4) and MK-9(H6). Mycolic acids were not detected. The major cellular fatty acids were iso-C16 : 0 and C17 : 1ω6c and C17 : 0ω8c. The DNA G+C content of the strain was 70.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed this strain clustered with the members of the genus Saccharomonospora and was closely related to Saccharomonospora xinjiangensis, Saccharomonospora azurea and Saccharomonosporacyanea. The levels of similarity between this strain and the closely related species were: Sxinjiangensis BCRC16887^T, 98.34 %; S. azurea BCRC 16220^T, 98.27 %; and S. cyanea BCRC 16886^T, 97.99 %. Based on phylogenetic characteristics, strain 06168H-1^T represents a novel species of the genus Saccharomonospora. We thus propose the name Saccharomonospora piscinae sp. nov. for this novel strain, with strain 06168H-1^T (=BCRC 16893^T=KCTC 19743^T) as the type strain.

Necroptosis promotes autophagy-dependent upregulation of DAMP and results in immunosurveillance

Programmed necrosis, necroptosis, is considered to be a highly immunogenic activity, often mediated via the release of damage-associated molecular patterns (DAMPs). Interestingly, enhanced macroautophagic/autophagic activity is often found to be accompanied by necroptosis. However, the possible role of autophagy in the immunogenicity of necroptotic death remains largely obscure. In this study, we investigated the possible mechanistic correlation between phytochemical shikonin-induced autophagy and the shikonin-induced necroptosis for tumor immunogenicity. We show that shikonin can instigate RIPK1 (receptor [TNFRSF]-interacting serine-threonine kinase 1)- and RIPK3 (receptor-interacting serine-threonine kinase 3)-dependent necroptosis that is accompanied by enhanced autophagy. Shikonin-induced autophagy can directly contribute to DAMP upregulation. Counterintuitively, among the released and ectoDAMPs, only the latter were shown to be able to activate the cocultured dendritic cells (DCs). Interruption of autophagic flux via chloroquine further upregulated ectoDAMP activity and resultant DC activation. For potential clinical application, DC vaccine preparations treated with tumor cells that were already pretreated with chloroquine and shikonin further enhanced the antimetastatic activity of 4T1 tumors and reduced the effective dosage of doxorubicin. The enhanced immunogenicity and vaccine efficacy obtained via shikonin and chloroquine cotreatment of tumor cells may thus constitute a compelling strategy for developing cancer vaccines via the use of a combinational drug treatment.

Inhibitory effects of constituents of an endophytic fungus Hypoxylon investiens on nitric oxide and interleukin-6 production in RAW264.7 macrophages

Three new compounds, hypoxyloamide (1), 8-methoxynaphthalene-1,7-diol (2), and hypoxylonol (3), together with seven compounds isolated from nature for the first time, investiamide (4), hypoxypropanamide (5), hypoxylonol A (6), investienol (7), 2-heptylfuran (8), (3S)-5-methyl-8-O-methylmellein (9), (4R)-O-methylsclerone (10), along with 19 known compounds, 11-29, were isolated from the culture broth of Hypoxylon investiens BCRC 10F0115, a fungal endophyte residing in the stems of an endemic Formosan plant Litsea akoensis var. chitouchiaoensis. The structures of the new compounds were established by spectroscopic methods, including UV, IR, HR-ESI-MS, and extensive 1D- and 2D-NMR techniques. Of these isolates, 2, 8-methoxynaphthalen-1-ol (15), and 1,8-dimethoxynaphthalene (16) showed nitric oxide (NO) inhibitory activity with IC50 values of 11.8±0.9, 17.8±1.1, and 13.3±0.5 μM, respectively, stronger than the positive control quercetin (IC50 36.8±1.3 μM). Compounds 2, 15, and 16 also showed interleukin-6 (IL-6) inhibitory activity with IC50 values of 9.2±1.7, 18.0±0.6, and 2.0±0.1 μM, stronger than the positive control quercetin (IC50 31.3±1.6 μM). To the best of our knowledge, this is the first report on guaiane sesquiterpene metabolites, 3, 6, and 7, from the genus Hypoxylon.

Identification of the mokH gene encoding transcription factor for the upregulation of monacolin K biosynthesis in Monascus pilosus

Monacolin K is a secondary metabolite synthesized by polyketide synthases (PKS) from Monascus. The monacolin K biosynthetic gene cluster, mokA-mokI, has been characterized in Monascus pilosus. The mokH gene encoding Zn(II)2Cys6 binuclear DNA binding protein is assumed to be an activator for monacolin K production. In this study, the mokH gene was cloned and driven by the glyceraldehyde-3-phosphate dehydrogenase (gpd) promoter for overexpression in M. pilosus. The transformants containing an extra copy of the mokH gene were obtained and verified by PCR and Southern hybridization. The transcripts of mokH in the transformants were expressed significantly higher than those of the wild-type strain. The transformants were stably inherited through the next generation, as determined by observation of the enhanced green fluorescent protein (EGFP). The transformant T-mokH1 also showed a 1.7-fold higher production of monacolin K than the wild-type strain in a time course analysis. Analysis of the RT-PCR products demonstrated that the monacolin K biosynthetic genes in the transformant were expressed to a greater extent than those in the wild-type strain. These results indicated that mokH upregulated the transcription of monacolin K biosynthetic genes and increased monacolin K production.

Aberrant caspase-activated DNase (CAD) transcripts in human hepatoma cells

The gene of caspase-activated DNase (CAD), the key enzyme for nucleosome cleavage during apoptosis, is mapped at chromosome 1p36, a region usually associated with hemizygous deletions in human cancers, particularly in hepatoma (HCC). It is tempting to speculate that CAD plays a tumour-suppressive role in hepatocarcinogenesis. To address this, we examined the CAD transcripts in six human HCC cell lines, one liver tissue from a non-HCC subject, and peripheral blood leukocytes (PBL) from three healthy individuals. Alternatively spliced CAD transcripts with fusion of exon 1 to exon 7 were isolated in most of the examined samples including HCC cells and normal controls. However, relatively abundant alternatively spliced CAD transcripts with fusion of exon 2 to exon 6 or 7, in which the corresponding domain directing CAD interaction with ICAD was preserved, were found only in poorly differentiated Mahlavu and SK-Hep1 cells. Interestingly, an abnormal CAD transcript with its exon 3 replaced by a truncated transposable Alu repeat was isolated in Hep3B cells, indicative of the implication of an Alu-mediated genomic mutation. Moreover, mis-sense mutations in the CAD genes were identified in all six HCC cell lines. Upon UV-induced apoptosis, DNA fragmentation efficiency was found to be intact, partially reduced and remarkably reduced in Huh7 and J328, Hep3B and HepG2, and Mahlavu cells, respectively. That mutations and aberrantly spliced transcripts for the CAD gene are frequently present in human HCC cells, especially in poorly differentiated HCC cells, suggests a significant role of CAD in human hepatocarcinogenesis.

Genome-wide hypomethylation in hepatocellular carcinogenesis

Aberrant genome-wide hypomethylation has been thought to be related to tumorigenesis. However, its mechanism and implications in hepatocellular carcinogenesis remain to be elucidated. Samples of hepatoma (hepatocellular carcinoma, HCC) and paired non-HCC liver tissues were obtained from 17 HCC patients. Normal liver tissues obtained from three individuals were used as controls. Compared with the paired non-HCC liver tissues, genome-wide 5-methylcytosine content in HCC was reduced in all of the tested HCC samples (P < 0.001). Conversely, genome-wide 5-methylcytosine content did not significantly differ among normal, noncirrhotic, and cirrhotic liver tissues. Moreover, the degree of reduced DNA methylation was related to late histopathological HCC grade (P = 0.005) and large tumor size (P = 0.079). Compared with the paired non-HCC liver tissues, expression of DNA methyltransferases DNMT-1, DNMT-3A, and DNMT-3B and the DNA methyltransferase-like gene, DNMT-2, was up-regulated in 53, 41, 59, and 47% of the HCC samples, respectively. Surprisingly, small amounts of LINE-1 retrotransposon transcripts were detected in HCC and non-HCC as well as normal liver tissues, and the expression levels were not significantly different in HCC compared with the paired non-HCC or normal liver tissues. Of interest, the 3' ends of these LINE-1 transcripts were truncated. Our findings suggest that genome-wide hypomethylation in HCC is a continuing process that persists throughout the lifetime of the tumor cells rather than a historical event occurring in precancer stages or in cell origins for HCC. Up-regulation of DNA methyltransferases might simply be a result of increased cell proliferation in cancer. In addition, our results did not support the hypothesis of activation of transposable elements in HCC via genome-wide hypomethylation.

Correlation of mutational analysis to clinical features in Taiwanese patients with Gilbert's syndrome

OBJECTIVES

Mutations in the promoter as well as in the coding region of the bilirubin UDP-glucuronosyltransferase gene (UGT1A1) have been found to be associated with Gilbert's syndrome. However, the genetic basis of Gilbert's syndrome in our population and correlation of these mutations to fasting serum bilirubin levels in patients with Gilbert's syndrome remain to be clarified.

METHODS

We applied polymerase chain reaction-based direct-sequencing assays to examine mutations in UGT1A1 gene in 20 unrelated Gilbert's patients and in a family with Gilbert's syndrome.

RESULTS

We studied three mutations that were previously reported to be associated with Gilbert's syndrome (i.e., the TATAA-box mutation, Gly71Arg, and Pro229Gln) in 20 patients with Gilbert's syndrome. Of the patients, 16, five, and six were found to have the TATAA-box, Gly71Arg and Pro229Gln mutations, respectively. Seven patients had simultaneous mutations both in the TATAA box and in the coding region. Of note, all six patients with Pro229Gln also had the TATAA-box mutation. Localization of Pro229Gln on the allele containing the TATAA-box mutation was demonstrated in a family with Gilbert's syndrome. The patients simultaneously heterozygous for both the TATAA-box mutation and Gly71Arg usually had serum bilirubin levels similar to those found in the patients homozygous for the TATAA-box mutation, but usually higher than those found in the patients heterozygous for the TATAA-box mutation alone. On the other hand, concurrence of Pro229Gln in patients with TATAA-box mutation or with Gly71Arg did not significantly affect serum bilirubin levels.

CONCLUSIONS

The TATAA-box mutation and Gly71Arg are the major causes for Gilbert's syndrome in our population. Concurrence of mutations of Gly71Arg and TATAA-box usually exerts a synergistic effect on hyperbilirubinemia. Pro229Gln, which is regularly linked to the TATAA-box mutation, may not have a significant effect on serum bilirubin levels.

Olone modulates the therapeutic effect of interferon to eliminate preferentially the hepatitis B virus precore stop mutant

BACKGROUND/AIMS

The aim of this study was to understand the changes in the proportion of hepatitis B virus precore stop mutant during the course of prednisolone primed interferon (IFN) therapy.

METHODS

Three groups of patients were included: patients receiving prednisolone-primed IFN treatment (Group I, n=31), IFN treatment only (Group II, n=29), and placebo (Group III, n=25). The proportion of precore stop mutant was measured by a quantitative amplification-created restriction site method.

RESULTS

Distinct patterns of the progression of the proportion of mutant were found among these three groups. A steady increase in the proportion of mutant was observed only in Group III patients. In Group II patients, the presence of a higher percentage of mutant (> 25%) immediately before IFN treatment was predictive for the subsequent clearance of hepatitis B e antigen (HBeAg) (p<0.01), but not for complete anti-viral response (p>0.05). Prednisolone pretreatment resulted in an increase in the proportion of mutant in patients with initially low percentages (< or = 25%) of mutant. During the period of IFN treatment, both the relative and absolute amount of the precore stop mutant decreased significantly in Group I patients who cleared HBeAg. The presence of such a decrease in this group of patients was predictive for both HBeAg clearance and complete anti-viral response.

CONCLUSIONS

Our data suggest that prednisolone serves as a modulator to enhance elimination of precore stop mutant by IFN, which advocates the benefit of corticosteroid pretreatment in an area where the precore mutants are prevalent.

Case report: Clostridium septicum infection presenting as liver abscess in a case of choriocarcinoma with liver metastasis

Clostridium septicum is an anaerobic, gram-positive bacillus. Infection with this organism has a known association with malignant diseases, especially colon and haematological cancers. Clostridium septicum is rarely found to be a pathogen of liver abscess. Herein, we report the case of a female choriocarcinoma patient with liver metastasis in which C. septicum infection presented as a gas-forming liver abscess. This case and previous reports indicate that once C. septicum is identified as a pathogen in liver abscess, metastatic liver tumours should be highly suspected.

Identity of a novel swine hepatitis E virus in Taiwan forming a monophyletic group with Taiwan isolates of human hepatitis E virus

Recently, we found that more than 10% of the cases of acute non-A, non-B, non-C hepatitis in Taiwan were caused by a novel strain of hepatitis E virus (HEV). Since none of these patients had a history of travel to areas where HEV is endemic, the source of transmission remains unclear. The recent discovery of a swine HEV in herd pigs in the United States has led us to speculate that HEV may also circulate in herd pigs in Taiwan and may serve as a reservoir for HEV in Taiwan. Of 275 herd pigs obtained from 10 pig farms in Taiwan, 102 (37%) were seropositive for serum anti-HEV immunoglobulin G (IgG). A 185-bp genomic sequence within the ORF-2 of the HEV genome was amplified and cloned from serum samples of an anti-HEV positive pig and subsequently from serum samples of a patient with acute hepatitis E. Sequence comparison revealed that the swine and human isolates of HEV share 97.3% identity. Phylogenetic analyses further showed that the Taiwan swine and human isolates of HEV form a distinct branch divergent from all other known strains of HEV, including the U.S. swine strain. To examine the potential risk of cross-species transmission of swine HEV to humans, the seroprevalences of anti-HEV IgG in 30 swine handlers, 20 pork dealers, and 50 control subjects were assessed and were found to be 26.7, 15, and 8%, respectively (for swine handlers versus controls, P = 0.048). Our findings may help provide an understanding of the modes of HEV transmission and may also raise potential public health concerns for HEV zoonosis.

High prevalence of TT virus infection in healthy children and adults and in patients with liver disease in Taiwan

A newly identified DNA virus, named TT virus (TTV), was found to be related to transfusion-associated hepatitis. We conducted the following experiments to evaluate its pathogenic role in liver disease and potential modes of transmission. We used PCR to detect TTV DNA in serum. The rates of TTV viremia in 13 patients with idiopathic acute hepatitis, 14 patients with idiopathic fulminant hepatitis, 22 patients with chronic hepatitis, and 19 patients with cirrhosis of the liver were 46, 64, 55, and 63%, respectively, and were not significantly different from those in 50 healthy control subjects (53%). PCR products derived from seven patients with liver disease and three healthy controls were cloned and then subjected to phylogenetic analyses, which failed to link a virulent strain of TTV to severe liver disease. TTV infection was further assessed in an additional 148 subjects with normal liver biochemical tests, including 30 newborns (sera collected from the umbilical cord), 23 infants, 16 preschool children, 21 individuals of an age prior to that of sexual experience (aged 6 to 15 years), 15 young adults (aged under 30 years), and 43 individuals older than 30 years. The rates of TTV viremia were 0, 17, 25, 33, 47, and 54%, respectively. These findings suggest that TTV is transmitted mainly via nonparenteral daily contact and frequently occurs very early in life and that TTV infection does not have a significant effect on liver disease.

Etiology of sporadic acute viral hepatitis in Taiwan: the role of hepatitis C virus, hepatitis E virus and GB virus-C/hepatitis G virus in an endemic area of hepatitis A and B

The etiology of sporadic acute hepatitis was studied in 334 consecutive patients from Taiwan (237 men and 97 women, aged 16-81 years), with emphasis on the role of hepatitis C virus (HCV), hepatitis E virus (HEV), and GB virus-C/hepatitis G virus (GBV-C/HGV) in acute non-A, non-B (NANB) hepatitis and in HBsAg carriers with superimposed acute hepatitis. According to the conventional diagnostic criteria, there were 12 cases (3.6%) of acute hepatitis A, 17 cases (5.1%) of acute hepatitis B, 128 cases (38.3%) of acute NANB hepatitis, and 177 cases (53.0%) of acute hepatitis in HBsAg carriers (those who were HBsAg positive but IgM anti-HBc negative). Among 128 cases of acute NANB hepatitis, 70 (54.7%) had acute hepatitis C (HCV RNA positive), 5 (3.9%) had acute hepatitis E (IgM anti-HEV positive), and the other 53 (41.4%) were presumably acute hepatitis non-A-E. The prevalence of acute hepatitis A, B, E, and non-A-E showed no significant sex difference, whereas acute hepatitis C was significantly more prevalent in females. The prevalence of acute hepatitis A and B decreased and that of acute hepatitis C increased significantly with increasing age. In contrast, acute hepatitis E and non-A-E showed no significant age predominance. Of 177 HBsAg carriers with acute hepatitis, 64 (36.1%) demonstrated non-B hepatotropic virus superinfection, with HCV being the most common (60.9%), followed by hepatitis D, E, and A viruses, and the other 55 (31.1%) and 58 (32.8%) were presumed to have acute exacerbation of chronic hepatitis B or superimposed acute hepatitis non-A-E, respectively. Serum GBV-C/HGV RNA was detected in 3-4% of acute hepatitis non-A-E cases, suggesting its limited role in these cases.

Primary hepatic angiosarcoma: report of a case involving environmental arsenic exposure

Hepatic angiosarcoma is a rare malignant tumor with a rapidly fatal course. It has become a subject of interest because of its intimate relationship with environmental carcinogens, such as thorium dioxide (Thorotrast), vinyl chloride monomer, and arsenic. We describe a case of a chronic hepatitis B surface antigen carrier, with a 20-year history of environmental exposure to arsenical-containing agricultural herbicides and bactericides, who developed a hepatic angiosarcoma. He died due to rupture of the hepatic angiosarcoma with acute hemoperitoneum 9 weeks after initial diagnosis. This is a rare case of primary hepatic sarcoma, especially in Taiwan where hepatocellular carcinoma is endemic. This case not only serves to give more evidence of the relationship between hepatic angiosarcoma and arsenical exposure, but also demonstrates the key point in the differential diagnosis of liver tumors. Increased familiarity with this disease will facilitate correct diagnosis and help to improve management of the condition in the future.

Emergence of an S gene mutant during thymosin alpha1 therapy in a patient with chronic hepatitis B

The presence of a hepatitis B virus S gene mutant was investigated in a patient being treated with thymosin alpha1. He was seropositive for hepatitis B e antigen throughout therapy but was intermittently seronegative for hepatitis B surface antigen (HBsAg) by an RIA. Sequence analysis revealed an S gene mutant in HBsAg-seronegative serum with two consecutive amino acid substitutions: threonine115-to-isoleucine and threonine116-to-asparagine, whereas no amino acid substitution or deletion was found in the pre-S region. A site-directed mutagenesis experiment confirmed that these mutations were responsible for the failure to detect HBsAg. In summary, an S gene mutant was identified in an HBsAg-seronegative patient. The mutations were located outside the putative "a" determinant. The emergence of an S gene mutant during thymosin alpha1 treatment suggests that enhanced host immunity against HBsAg may play a role in its antiviral activity.

Identification of a novel strain of hepatitis E virus responsible for sporadic acute hepatitis in Taiwan

Hepatitis caused by the hepatitis E virus (HEV) is a self-limited disease and occurs most frequently as epidemic or sporadic hepatitis in developing countries. The role of HEV in sporadic acute hepatitis in areas without a history of hepatitis E epidemics is obscure. Recently, it was found that more than 10% of the patients with acute non-A, non-B, non-C hepatitis in Taiwan were associated with an acute HEV infection. Nucleotide sequences of the regions within the first open reading frame of HEV were determined in four cases and were 96.7-100% identical to each other. As compared to the isolates from China, Pakistan, Burma, India, Africa, and Mexico, the similarities were, however, only 71.7-79.3%. Phylogenetic analysis revealed that the four Taiwan isolates were categorized as a novel HEV group (the Taiwan strain), which was distinct from all of the strains isolated from other parts of the world. In addition, the isolates from China, Burma, India, and Pakistan were catalogued as the second genotype of HEV (the Asian strain), and the Mexican isolate as the third (the Mexican strain). The African isolate was more related to the Asian type and might be a subtype of the Asian strain. A simple genotyping method by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) is described. The findings also support the hypothesis that HEV may be responsible for some sporadic acute non-A, non-B, non-C hepatitis in other developed countries.

Change of thermal stability of colicin E7 triggered by acidic pH suggests the existence of unfolded intermediate during the membrane-translocation phase

Purified colicin E7 was analyzed by CD spectrum and gel filtration chromatography in a mimicking membrane-translocation phase. It was found that the CD spectra of colicin E7 at pH 7 and pH 2.5 were similar. Although the melting temperature of the protein shifted from 54.5 degrees C to 34 degrees C at low pH, the thermal denaturation curves of colicin E7 at different pH conditions still fit a two-state model. These experimental results imply that a minor structural change, triggered by acidic pH, for instance, may reduce the energy required for protein melting. In contrast to the minor change in secondary structure at different pH conditions, we observed that, in vitro, all monomeric colicin E7s converted into multimer-like conformations after recovering from the partial unfolding process. This multimeric form of colicin can only be dissociated by formamide and guanidine hydrochloride, indicating that this protein complex is indeed formed by aggregation of the monomeric colicins. Most interestingly, the aggregated colicins still perform in vivo bacteriocidal activity. We suggest that in a partial unfolding state the colicin is prepared for binding to the specific targets for translocation through the membrane. However, in the absence of specific targets in vitro these unfold intermediates may therefore aggregate into the multimeric form of colicins.

Clinical and virological course of chronic hepatitis B virus infection with hepatitis C and D virus markers

OBJECTIVE

Hepatitis B, C, and delta virus (HBV, HCV, HDV) share similar transmission routes; thus, dual or triple infections may occur and even persist in the same patient. However, little is known about the presentations and course of chronic HBV infection with HCV and HDV markers, which this study examined.

METHODS

Antibodies against HCV (anti-HCV) and HDV (anti-HDV) were assayed as appropriate in patients with HBV infection. The clinical, pathological, and virological presentations as well as the course of the disease in patients with HBV/HDV/HCV triple infection markers were then reviewed.

RESULTS

A total of 60 patients, 51 men and nine women, age 19-67 yr (mean 45.9+/-1.6 yr) were identified. Of these 60 patients, five (8.3%) were HBeAg positive and 10 (16.7%) cirrhotic at entry, 30 (50%) presented with acute superinfection (HCV or HDV, or both) and the remaining 30 presented with chronic liver disease. On presentation, 16 (53.3%) of the 30 patients with acute superinfection showed hepatic decompensation and eight (26.7%) died. In contrast, only one of the patients with "chronic liver disease" presented with hepatic decompensation. Of the 42 patients followed up for 1-15 (mean, 4.7+/-0.6) yr, 45.2% showed remission and 19% showed HBsAg seroclearance, whereas 12.5% of the 32 noncirrhotics developed cirrhosis and three of the nine cirrhotics became decompensated. At the end of follow-up, 29 patients (69.9%) were still seropositive for HCV-RNA but only nine (22.5%) were seropositive for HDV-RNA and five (12.5%) were seropositive for HBV-DNA.

CONCLUSIONS

These results suggest that infection with HBV, HCV, and HDV triple markers is a severe disease in acute superinfection stage but that the course is relatively benign, slowly progressive, and usually dominated by HCV.

High-performance liquid chromatographic determination of clindamycin in human plasma or serum: application to the bioequivalency study of clindamycin phosphate injections

This paper presents an assay of clindamycin phosphate injection in human plasma or serum. A 0.5-ml volume of plasma was used with the internal standard, propranolol. The sample was loaded onto a silica extraction column. The column was washed with deionized water and then eluted with methanol. The eluates were evaporated under nitrogen gas. The residue was reconstituted with the mobile phase and injected onto the high-performance liquid chromatographic system: a 5-micron, 25 cm X 4.6 mm I.D. ODS2 column was used with acetonitrile, tetrahydrofuran and 0.05 M phosphate buffer as the mobile phase and with ultraviolet detection at 204 nm. A limit of quantitation of 0.05 microgram/ml was found, with a coefficient of variation of 11.6% (n = 6). The linear range is between 0.05 and 20.00 micrograms/ml and gives a coefficient of determination (r2) or 0.9992. The method has been successfully applied to the bioavailability study of two commercial preparations of clindamycin phosphate injection (300 mg each) in twelve healthy adult male volunteers.

Cloning and characterization of the extreme 5'-terminal sequences of the RNA genomes of GB virus C/hepatitis G virus

The extreme 5'-terminal sequences of the GB virus C/hepatitis G virus (GBV-C/HGV), containing elements essential for regulation of viral gene expression and replication, have not been determined. By using a RNA-ligase-mediated RACE (rapid amplification of the cDNA ends) procedure, we have cloned the extreme 5'-terminal sequences of the viral genome from the serum of three Taiwanese patients. Sequence analysis of the 5' noncoding region in alignment with one West African and two American isolates showed that (i) a consensus 5'-end sequence was cloned; (ii) about 97% of sequences were homologous among the three Taiwan isolates and also between the two American isolates, whereas about 90% of sequences were homologous among the isolates from the three different geographic areas; (iii) the sequence heterogeneity related to geographic separation is confined mainly to three domains; and (iv) a potential hairpin structure, resembling the hairpin structure found in the 5' end of hepatitis C virus genome, was detected in the 5' end of the noncoding region. Our data support the hypotheses that (i) the extreme 5' end of the hepatitis GBV-C/HGV viral genome has been cloned, (ii) there are different genotypes correlated with geographic separation, and (iii) the viral translation and replication mechanisms may be similar to that of hepatitis C virus and pestiviruses. Our data have not only shed light on the viral replication mechanism but also offer information for selection of optimal primer sequences for the detection and genotyping of the hepatitis GBV-C/HGV virus by PCR assays.

A novel role of ImmE7 in the autoregulatory expression of the ColE7 operon and identification of possible RNase active sites in the crystal structure of dimeric ImmE7

Site-specific cleavage of mRNA has been identified in vivo for the polycistronic colicin E7 operon (ColE7), which occurs between G and A nucleotides located at the Asp52 codon (GAT) of the immunity gene (ceiE7). In vitro, this specific cleavage occurs only in the presence of the ceiE7 gene product (ImmE7). The crystal structure of dimeric ImmE7 has been determined at 1.8 A resolution by X-ray crystallographic analysis. We found that several residues located at the interface of dimeric ImmE7 bear surprising resemblance to the active sites of some RNases. These results suggest that dimeric ImmE7 may possess a novel RNase activity that cleaves its own mRNA at a specific site and thus autoregulates translational expression of the downstream celE7 gene as well as degradation of the upstream ceaE7 mRNA.

The crystal structure of the immunity protein of colicin E7 suggests a possible colicin-interacting surface

The immunity protein of colicin E7 (ImmE7) can bind specifically to the DNase-type colicin E7 and inhibit its bactericidal activity. Here we report the 1.8-angstrom crystal structure of the ImmE7 protein. This is the first x-ray structure determined in the superfamily of colicin immunity proteins. The ImmE7 protein consists of four antiparallel alpha-helices, folded in a topology similar to the architecture of a four-helix bundle structure. A region rich in acidic residues is identified. This negatively charged area has the greatest variability within the family of DNase-type immunity proteins; thus, it seems likely that this area is involved in specific binding to colicin. Based on structural, genetic, and kinetic data, we suggest that all the DNase-type immunity proteins, as well as colicins, share a "homologous-structural framework" and that specific interaction between a colicin and its cognate immunity protein relies upon how well these two proteins' charged residues match on the interaction surface, thus leading to specific immunity of the colicin.

Serum levels of interferon-alpha and -gamma in acute and chronic hepatitis B virus infection

To evaluate the potential implication of in vivo interferon production in the pathogenesis of different forms of acute and chronic hepatitis B virus infection, serum levels of interferon-alpha and -gamma were measured using immunoassay techniques in 20 patients with acute hepatitis B who subsequently cleared the virus (group Ia), 8 patients with acute hepatitis B who became HBsAg carriers (group Ib), 55 patients with chronic hepatitis B (group II), and 15 healthy controls. None of the controls had interferon-alpha or -gamma detectable in serum, while 15% and 100% of group Ia patients, 25% and 100% of group Ib patients, and 22% and 15% of group II patients, had raised serum levels of interferon-alpha and -gamma, respectively. Serum interferon-gamma was detected significantly more frequently in group Ia and Ib patients than in controls and in group II patients. Among patients with acute hepatitis B, serum levels of interferon-alpha and -gamma showed no significant difference between group Ia and group Ib patients. Among patients with chronic hepatitis B, interferon-alpha was detected significantly more frequently in patients with serum HBV-DNA (31.4% or 11/35) than in those without (5% or 1/20), whereas interferon-gamma was detected significantly more frequently in patients with chronic active hepatitis (28% or 7/25) than in those with chronic persistent hepatitis (3.3% or 1/30). In conclusion, in acute hepatitis B, serum levels of interferon-alpha and -gamma did not show a significant difference between patients who subsequently cleared the virus and those who became HBsAg carriers.(ABSTRACT TRUNCATED AT 250 WORDS)

A clinical study on pseudomyxoma peritonei

To elucidate the clinical entity of pseudomyxoma peritonei, nine patients (male: female = 6:3) who had been treated in Chang Gung Memorial Hospital in the past 13 years were reviewed. The male patients with original appendiceal tumour were older than the male patients with original colon cancer or indefinite tumour (70, 67 and 67 years vs 42, 27 and 50 years). In addition, the former group survived in a disease-free status for 28 months on average, while the latter group died within 2 years. Echogenic ascites and diffuse low-attenuation intra-abdominal masses with scalloping on the surface of liver detected by ultrasonography and by computerized tomography, respectively, were found in most of the patients. Elevation of the serum carcinoembryonic antigen (CEA) during recurrence of the disease was also noted. This series suggested that: (i) the pre-operative diagnosis could be made with careful physical examination in conjunction with sonography or computerized tomography; (ii) the prognosis was better in patients with tumour of appendiceal origin; and (iii) serum CEA might be valuable for early detection of recurrence.

Role of the ribozyme of hepatitis delta virus on the transcription after polyadenylation

We have previously demonstrated that the ribozyme located 34 nucleotides downstream of the polyadenylation site on the antigenomic RNA of the hepatitis delta virus can stabilize the downstream transcript after polyadenylation. Here, we have reports on further investigations of the molecular mechanism of this stabilization effect and the potential role of the small and large delta antigens. We found that the downstream transcripts after polyadenylation were stabilized by the ribozyme independently of either the small or large delta antigen. The stabilization effect was abolished as the ribozyme activity was eliminated by mutations on either the enzyme domain or target site of the ribozyme. These findings suggested that it was the ribozyme activity rather than the RNA structure or the delta antigens that contributed to the stabilization effect.