Regression of rectal MALT lymphoma after antibiotic treatment in a patient negative for Helicobacter pylori.

A 53-year-old man was referred to our hospital with bloody stool. Barium enema study and colonoscopy revealed multiple small nodules on the anterior wall of the lower rectum. Biopsy specimens showed proliferation of atypical lymphoid cells forming the nodules. Mucosa-associated lymphoid tissue lymphoma was diagnosed on the basis of histologic and immunohistochemical examinations. No metastasis was detected in lymph nodes or distant organs, indicative of clinical stage I disease. Although the test results were negative for Helicobacter pylori, eradication therapy was performed. The lesion disappeared completely within 9 months after the triple antibiotic therapy. H. pylori eradication therapy may be a useful treatment option regardless of H. pylori status.

[Increased serum PIVKA-II levels in hyperthyroidism].

PIVKA-II has been practically used as a tumor marker of hepatocellular carcinoma. On the other hand, increased serum PIVKA-II concentration was reported in a Japanese patient who had hyperthyroidism without liver diseases. To evaluate whether thyroid hormone is related with serum PIVKA-II, we examined serum PIVKA-II concentrations in patients with various thyroid diseases. Eight patients with Hashimoto disease, 24 patients with Graves' disease, and 8 healthy subjects were studied. There was no significant difference of serum PIVKA-II levels among the three groups. However, serum PIVKA-II concentrations(mean +/- SD mAU/ml) in hyperthyroidism(37 +/- 27) were significantly higher than those in hypothyroidism(16 +/- 9) and normal controls(12 +/- 4) (p < 0.05 and p < 0.01, respectively). When hyperthyroid patients were treated by antithyroid drug or isotope, serum PIVKA-II concentrations decreased in accordance with the decrease of serum FT4 concentrations. Our data indicate that serum PIVKA-II concentration was increased in patients with hyperthyroidism, but further in vivo studies are necessary to clarify the mechanism related to increased serum PIVKA-II by thyroid hormone.

[Increased serum soluble Fas ligand in hyperthyroid Graves' disease].

The interaction of Fas with its ligand (FasL) regulates a number of physiological and pathophysiological process of cell death or apoptosis. Recent studies suggest that Fas and Fas ligand (FasL) interactions among thyrocytes from patients with Hashimoto disease which is caused by thyroid autoimmunity may contribute to clinical hypothyroidism. The role of Fas-FasL interaction in the pathophysiology of Graves' disease has not well been determined. The serum levels of soluble Fas (sFas) and FasL (sFasL) were measured in 48 Japanese patients with Graves' disease (U; untreated hyperthyroidism, T; hyperthyroidism under treatment, E; euthyroidism under treatment and R; remission), destructive thyroiditis (D), subacute thyroiditis (S) and 40 normal controls using commercially available ELISA kits. The levels of sFas (mean +/- SD, ng/ml) were 0.93 +/- 0.30 in normal controls (n = 32), 2.41 +/- 1.28 in U (n = 19), 2.44 +/- 0.79 in T (n = 16), 2.37 +/- 0.55 in E (n = 12), and 2.30 +/- 0.11 in R (n = 6), 2.42 +/- 0.37 in D (n = 3) and 2.68 +/- 0.17 in S (n = 3). There were no significant differences of sFas levels among any groups. While, the mean levels of sFasL (ng/ml) of normal controls were 0.058 +/- 0.02 (n = 40), and those of patients with hyperthyroid Graves' disease (U; 0.34 +/- 0.09 and T; 0.26 +/- 0.05), were significantly higher than those in normal controls (p < 0.005) and with subacute thyroiditis (0.097 +/- 0.001, vs U; p < 0.01, vs T; p < 0.05) but not different from those in E, R and D (E; 0.34 +/- 0.09, R; 0.25 +/- 0.07 and D; 0.31 +/- 0.11, respectively). There was a significant correlation between serum thyrotropin receptor antibody (TRAb) and free thyroxine levels (p < 0.01) while there were no correlation between sFas and sFasL levels and TRAb or free thyroxine levels. The results indicate that the Fas-FasL system contributes to the pathophysiology of hyperthyroid Graves' disease although serum sFas and sFasL levels do not appear to be useful indicators in evaluating disease activity.

[An effective case of arterial infusion therapy of low-dose CDDP and continuous 5-FU for isolated hepatic recurrence of gastric carcinoma].

We report an effective case of arterial infusion therapy of low-dose CDDP and continuous 5-FU for isolated hepatic recurrence of gastric carcinoma. An 83-year-old man was admitted for epigastric pain and vomiting due to a huge liver metastasis of gastric carcinoma in May, 1997. Nineteen months earlier, in October of 1995, he had undergone distal gastrectomy and D2 lymph node dissection with Billroth I reconstruction. His conclusive stage and pathological findings were as follows. The conclusive stage was stage II: t3, n0, P0, H0. Histological typing was tub 2. Lymph node involvement was not detected, but venous invasion was found in the surrounding regional lymph nodes. CEA had been getting elevated from November, 1996. But he had been well until March, 1997, when CT scans revealed huge hepatic recurrence. The artery-side port was placed for hepatic arterial infusion therapy for liver metastasis. Intra-arterial bolus injection of low-dose CDDP (5 mg) and continuous intra-arterial infusion of 5-FU (250 mg/day for 7 days) were started. Through 4 courses of this arterial infusion therapy, the patient improved. CT scans revealed shrinking of liver metastasis after 3 months of this therapy. The patient was followed in an outpatient clinic and continued to receive this arterial infusion therapy once every 4 weeks. New lung metastasis was detected 9 months after the start, but liver metastasis continued to be responded. The patient died from bleeding into the bile duct from the liver metastasis 16 months after the start of arterial infusion therapy, when metastatic lesions of liver continued to shrink. Arterial infusion therapy of low-dose CDDP and continuous 5-FU may be effective for isolated hepatic recurrence of gastric carcinoma.

Identification of stable RNA hairpins causing band compression in transcriptional sequencing and their elimination by use of inosine triphosphate.

To identify stable RNA secondary structure causing band compression, 30 lambda DNA clones and four cDNA clones (about 10 kb in total length) were sequenced using Transcriptional Sequencing, which is based on the phage RNA polymerase chain termination reaction with fluorescent 3' deoxynucleoside triphosphate, using the canonical set of rNTPs for the substrate. Electrophoresis was performed on acrylamide gel containing 7 M urea at 50 degrees C using ABI 377 DNA sequencer. A total of 159 band compressions were identified, and most compression sites seem to be due to hairpin structures. We also found that the presence of rITP in place of rGTP in the sequencing reaction can entirely eliminate all band compressions. The use of rITP gave a better peak uniformity and resolution in the sequencing gel in the case of lambda DNA than with c7rGTP, leading to improved accuracy in the sequence determination. Substitution of the base analog rITP for rGTP should be useful for accurate sequencing determination.

Recognition sites of 3'-OH group by T7 RNA polymerase and its application to transcriptional sequencing.

When analyzing the elongation mechanisms in T7 RNA polymerase (T7 RNAP)by using site-directed mutagenesis and a protein expression system, we identified the recognition sites of the rNTP 3'-OH group in T7 RNAP. On the basis of three-dimensional crystal structure analysis, we selected and analyzed six candidate sites interacting with the 3'-OH group of rNTP in T7 RNAP. We found that the Phe-644 and Phe-667 sites are responsible for the high selectivity of T7 RNAP for rNTPs. Also, we constructed the protein mutations of these residues, F644Y and F667Y, which display a >200-fold higher affinity than the wild type for 3'-dNTPs. These findings indicate that the phenylalanine residues of 644 and 667 specifically interact with the 3'-OH group. Thus, these mutants, F644Y and F667Y, with incorporation of 3'-dNTP terminators, which is similar to native rNTPs, can offer low backgrounds and equal intensities of the sequencing ladders in our method, called "transcriptional sequencing. "

Syntheses of recombinant yellowtail and flounder growth hormones in Escherichia coli.

For syntheses of recombinant yellowtail and flounder growth hormones (r-yGH and r-fGH) in E. coli, expression plasmids were constructed. The expression level of r-yGH and r-fGH in the host cells were very high, reaching 15 and 8% of the total protein, respectively. These product proteins were accumulated in inclusion bodies in the cells. The recombinant hormones were isolated from the pellets ina glutathione reduction/oxidation buffer. The refolded hormones were further purified by DEAE-Toyopearl 650M chromatography to homogeneity. The purified r-yGH and r-fGH were composed of 188 and 174 amino acid residues, respectively, having amino-terminal sequences starting with methionine. The recombinant hormones had potent growth-promoting activities on juvenile rainbow trout Salmo gairdneri in a dose-dependent manner.

Cleavage action of a trypsin-like protease from Bacteroides gingivalis 381 on reduced egg-white lysozyme.

Soluble reduced lysozyme was extensively digested by a trypsin-like protease purified from the culture supernatant of the bacterium. The digestion peptides were separated and purified by reversed-phase high-performance liquid chromatography, and were subjected to amino acid analysis. The fragments were identified by their amino acid composition, and the cleavage sites in the lysozyme chain were determined. Like mammalian trypsin, the enzyme from B. gingivalis split peptide bonds non-specifically at carboxyl sides of internal arginine and lysine residues, but the lysine present at the amino terminus of the lysozyme chain was not released. In addition, the enzyme cleaved the peptide linkage at the amino side of lysine and bonds between leucine-glycine, alanine-leucine and leucine-serine. Thus the trypsin-like protease from B. gingivalis has some cleavage actions on lysozyme different from those of mammalian trypsin.