Katsuo Hayashi

Pyogenic granuloma of the stomach successfully treated by endoscopic resection after transarterial embolization of the feeding artery

Pyogenic granulomas represent the aquisition of vasodilative granulation tissue in the skin or mucosa. They are extremely rare in the alimentary tract, other than in the oral cavity. Here, we report a case of pyogenic granuloma arising from the gastric mucosa. An 82-year-old man was admitted to our hospital because of melena of more than 3 months, duration. Esophagogastroduodenoscopy (EGD) revealed a 30-mm-diameter semipedunculated lesion with an irregular surface in the fundus of the stomach. During hospitalization, the patient’s anemia worsened due to loss of blood from the lesion, with the level of hemoglobin declining to 6 g/dl, and a blood transfusion was required. Because radiological and endoscopic findings indicated the lesion was hypervascular, transarterial embolization of the nutritional artery of the lesion was performed before endoscopic resection of the lesion. One week after the embolotherapy, endoscopic mucosal resection was performed, without any complications, such as massive bleeding. Histological studies of the resected specimen revealed many capillaries of various sizes, lined with plump endothelial cells, and accompanied by acute and chronic inflammatory infiltrates. On the basis of these observations, the lesion was diagnosed as a pyogenic granuloma. One year later, the patient was asymptomatic and there was no evidence of tumor recurrence on follow-up EGD.

Molecular Evolutionary Analysis of the Complete Nucleotide Sequence of Hepatitis B Virus (HBV) in a Case of HBV Infection Acquired through a Needlestick Accident

To elucidate needlestick transmission of hepatitis B virus (HBV), strains isolated from 1 physician who acquired HBV infection through a needlestick accident and 3 patients with chronic hepatitis B (donor patients A, B, and C) were tested using molecular evolutionary analysis based on full-length HBV genomic sequences. Nucleotide sequences of these isolates were aligned with 55 previously reported full-length genomic sequences. Genetic distances were estimated using the 6-parameter method, and phylogenetic trees were constructed using the neighbor-joining method. Strains isolated from patient A and the recipient pair were clustered within a closer range of evolutionary distances than were strains recovered from the recipient pair and patients B and C. Furthermore, strains from patient A and the recipient were also clustered on the S gene sequences of HBV. These results demonstrated that patient A alone was the source of direct transmission to the recipient. This approach can be used to investigate the transmission route of HBV.

Automated determination of 5-fluorouracil and its metabolite in urine by high-performance liquid chromatography with column switching.

We report a quantitative assay of 5-fluorouracil (FU) and its metabolite, 5-fluorodihydrouracil (FDHU) in human urine by used a column-switching high-performance liquid chromatographic method. The analyses were carried out using a molecular exclusion column for sample purification, and a cation-exchange column for separation. Each sample required only 40 min to analyze, and required no preparation other than filtration. Linearity was verified up to 1000 nmol/ml (r > 0.993). The recovery of FU was 96-101%; recovery of FDHU was 96-105%. The imprecision (RSD) for FU (10-100 nmol/ml) was < 1.5%, same-day (n = 5), and < 1.8%, day-to-day (n = 5). The imprecision (RSD) for FDHU (10-100 nmol/ml) was < 3.2%, same-day (n = 5), and < 4.0%, day-to-day (n = 5). The detection limits were, respectively, 0.1 nmol/ml. We measured FU and FDHU in urine of seven cancer patients after oral administration of FU. The cumulative quantity ratio of the FDHU and FU (FDHU/FU) excreted in their urine within 120 min after FU administration was a constant value in all seven patients. Based on these results, we believe that our method provides a useful tool for evaluating FU metabolism.

Lack of association between TTV viral load and aminotransferase levels in patients with hepatitis C or non-B-C.

TT virus (TTV) is a newly identified un-enveloped single-stranded DNA virus. Although TTV was initially thought to be a new hepatitis virus, it is still unclear whether it causes hepatitis. To clarify the natural history and pathogenesis of TTV infection, serial serum samples from patients with chronic hepatitis were analysed. TTV DNA was quantified by real-time detection polymerase chain reaction assay (RTD-PCR), which was adapted for TTV. Five patients with chronic hepatitis, 4 with hepatitis C and 1 with non-B-C, were studied. The study period ranged from 9 to 50 months. In 3 patients there were frequent increases in TTV DNA titres, but no concomitant elevation of the aminotransferase (ALT) levels. In 2 patients who were treated with interferon, the changes in TTV titres were not synchronized with those of the ALT levels. Thus, in cases of chronic hepatitis, no correlation was observed between the serum TTV DNA titres and the ALT levels.TT virus (TTV) is a newly identified un-enveloped single-stranded DNA virus. Although TTV was initially thought to be a new hepatitis virus, it is still unclear whether it causes hepatitis. To clarify the natural history and pathogenesis of TTV infection, serial serum samples from patients with chronic hepatitis were analysed. TTV DNA was quantified by real-time detection polymerase chain reaction assay (RTD-PCR), which was adapted for TTV. Five patients with chronic hepatitis, 4 with hepatitis C and 1 with non-B-C, were studied. The study period ranged from 9 to 50 months. In 3 patients there were frequent increases in TTV DNA titres, but no concomitant elevation of the aminotransferase (ALT) levels. In 2 patients who were treated with interferon, the changes in TTV titres were not synchronized with those of the ALT levels. Thus, in cases of chronic hepatitis, no correlation was observed between the serum TTV DNA titres and the ALT levels.

Identification of a novel 23 kDa protein encoded by putative open reading frame 2 of TT virus (TTV) genotype 1 different from the other genotypes

Summary. We report the entire open reading frames (ORFs) sequences of four TT virus (TTV) isolates, one genotype 2 (G2) and three G4 isolates. Despite a DNA virus, TTV possesses high rate of amino acid (aa) substitution: the aa sequence homology of ORF1 and 2 is lower than the nucleotide homology. The partial ‘N22’ region of ORF1 is suitable for genotyping of ‘prototype TTV’ isolates, because the phylogenetic tree from partial ‘N22’ sequence is consistent with that from the entire ORF1. Based on our sequence data, ORF2 from most isolates excluding G1 encode truncated 49 aa (pORF2a) because of an in-frame stop codon, although ORF2s from most G1 isolates encode 202 aa (pORF2ab). Just downstream the stop codon, another ORF encoding a protein of approximately 150 aa (pORF2b) is found, whose homology is quite low among these genotypes. Our in vitro transcription/translation study supports that all G1a and a part of G1b without an in-frame stop codon dominantly encode pORF2ab, a novel 23 kDa protein, whereas the other genotypes with an in-frame stop codon encode pORF2b (17 kDa). Our data indicate TTV G1a and a part of G1b should have different characteristics from the other genotypes.

Urinary Screening for Pyrimidine Metabolism Disorders

Pyrimidine chemotherapy agent such as 5-FU are used widely but can occasionally cause serious adverse reactions in patients with pyrimidine metabolism disorders. The screening method which entailed measuring dihydropyrimidine dehydro- genase activity (DPD) has been reported. This method is acceptable with small groups, but difficulties arise when dealing with large populations owing to the complicated procedure for measuring enzyme activity. We have studied the urinary screening method using high-performance liquid chromatograpy, which is acceptable with large groups.1 This method can diagnose not only dihydropyrimidine dehydrogenase deficiency but also dihydropyrimidinuria. Using this method, we have analyzed urinary dihydrouracil (DHU) and uracil concentrations in 167 healthy adults and 966 patients with malignancy, hypertension, cerebral infarction, etc. In order to establish the reference ranges of urinary pyrimidine, we used “log (concentration)”. Additionally, we calculated dihydrouracil/uracil ratio, which seemed to be reflected of DPD activity.

Variations in the viral NS5B region in Japanese patients with chronic hepatitis C virus genotype 1b infection : No specific amino acid substitution was identified as determinants of treatment response to interferon/ribavirin combination therapy

Objective: A recent study suggested that the substitution of amino acid 415 of HCV NS5B from phenylalanine to tyrosine in patients with HCV genotype 1a infection is induced by ribavirin and responsible for resistance to ribavirin therapy. The aim of this study was to evaluate whether specific variations in the HCV NS5B sequence in Japanese patients with HCV genotype 1b (HCV/1b) infection are associated with treatment response or selected by treatment with interferon-α/ribavirin combination therapy. Methods: Eighteen Japanese patients with HCV/1b infection receiving interferon-α/ribavirin combination therapy for 24 weeks were studied. Five patients treated with interferon-α monotherapy for 24 weeks were also studied as controls. The entire HCV NS5B sequence before and after therapy was determined. Results: All HCV isolates had tyrosine at position 415 of NS5B before and after therapy. Further analysis showed that no specific amino acid substitutions were identified to associate with clinical response and no specific amino acid substitutions were induced/selected by the clinical treatment. Conclusion: No specific HCV NS5B nucleotide/amino acid sequence variations, including amino acid 415 of NS5B, were identified as being associated with clinical treatment response or selected by the combination therapy in Japanese patients with HCV/1b infection.

Nucleotide and amino acid diversities of E2/NS1 hypervariable region 1 and response to interferon therapy in patients with chronic hepatitis C virus infection

Abstract To clarify the relationship between nucleotide and amino acid diversities of the E2/NS1 hypervariable region 1 (HVR1) of hepatitis C virus (HCV) and response to subsequent interferon- α (IFN) therapy, pretreatment serum samples were studied from 13 Japanese patients, who were infected with HCV genotype 1b, had similar histological profiles and serum HCV RNA levels (1–10 million eq ml −1 ), and were subsequently treated with the same IFN treatment protocol. Nucleotide sequence of HVR1 was determined by dideoxynucleotide chain termination in eight clones derived from each serum sample. Nucleotide and amino acid diversities were calculated from the mean of the genetic distances among these eight clones by six-parameter method. Of the 13 patients, four showed a complete and sustained response, three were complete responders followed by early relapse, and six were non-responders to IFN therapy. No significant differences in clinical or virological parameters among the three groups were found. There was no significant difference in the diversity of HVR1 among the three groups, indicating that when host and viral factors were controlled, nucleotide and amino acid diversities in HCV HVR1 might not correlate well with response to IFN.