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T Ueda

Publications and source records attributed to T Ueda.

At least 19 recordsLinked to original sources
PubMed1992

A novel anti-HIV synthetic peptide, T-22 ([Tyr5,12,Lys7]-polyphemusin II).

Tachyplesin and polyphemusin are antimicrobial peptides recently isolated from the hemocytes of horseshoe crabs (Tachypleus tridentatus and Limulus polyphemus). We synthesized them and their analogs and examined their antiviral activity against human immunodeficiency virus (HIV) type 1 in vitro. The infection of human T cells with the virus was markedly inhibited by some of them at low concentrations. In this structure-activity study, we found that [Tyr5,12, Lys7]-polyphemusin II, which was designated as T22, had extremely high anti-HIV activity. Its 50% inhibitory concentration (EC50) was 0.008 micrograms/ml, while its 50% cytotoxic concentration (CC50) was 54 micrograms/ml and these values were comparable to those of AZT. This result indicates that T22 would be a potential candidate for the therapy of HIV infection.

Amino Acid Sequence↗
PubMed1992

Interleukin 6/B cell stimulatory factor-II is expressed and released by normal and transformed human bronchial epithelial cells.

Airway epithelial cells have a potential to participate in local immune and inflammatory responses via releasing biologically active compounds. We studied the expression and release of interleukin 6 (IL-6), a multifunctional cytokine possibly involved in tissue immune responses. Primary culture of normal human bronchial epithelial cells and its transformed cell line BEAS-2B released significant amount of biologically and immunologically intact IL-6 into media. A protein synthesis inhibitor cycloheximide abolished the IL-6 release, suggesting a de novo synthesis. Northern blot analysis demonstrated the expression of the specific IL-6 mRNA. Human bronchial epithelial cells can produce IL-6 and contribute to the local activity of IL-6, suggesting that these cells may play a role in the regulation of airway immune responses.

Antibodies, Monoclonal↗
PubMed1992

[Intraarterial urokinase infusion therapy with superselective catheterization for acute occlusive cerebrovascular disease].

Intraarterial urokinase infusion therapy with superselective catheterization was performed on 11 patients for acute occlusive cerebrovascular disease. The subjects were five men and six women with a mean age of 70 years (range, 48-83 years). Nine of 11 patients had middle cerebral artery occlusion and two had basilar artery occlusion. The interval from onset to infusion ranged from 3.5 to 9 hours, and the total dosage of urokinase from 24 x 10(4) to 150 x 10(4) IU. Recanalization of the occluded artery was achieved in nine patients (82%), and favorable clinical outcome was achieved in seven patients (64%). Six of whom were discharged with no neurologic deficits. Hemorrhagic infarction occurred in two patients without clinical deterioration. Our observations suggest that intraarterial urokinase infusion therapy with superselective catheterization may be very useful in the acute stage of occlusive cerebrovascular disease.

Acute Disease↗
PubMed1992

Serine tRNA complementary to the nonuniversal serine codon CUG in Candida cylindracea: evolutionary implications.

In the asporogenic yeast Candida cylindracea, the codon CUG is read as serine instead of leucine. This is an unusual instance in which the amino acid assignment of a codon deviates from the universal code. To infer the evolutionary process of this change, the tRNA with the anticodon sequence CAG, which is complementary to and thus responsible for translation of the codon CUG, has been identified. Indeed, this tRNA translates an in-frame CUG codon in a synthetic mRNA as serine in an in vitro translation system. The gene for the tRNA is interrupted by an intron in the anticodon loop. Sequence comparisons of the tRNA and its gene suggest that a single cytidine was inserted into the anticodon loop of the gene for tRNA(Ser)IGA during evolution to produce tRNA(Ser)CAG. The tRNA(Ser)CAG may be produced from its precursor molecule containing the cytidine insertion by splicing.

Amino Acid Sequence↗
PubMed1992

Glutamate transport into synaptic vesicles. Roles of membrane potential, pH gradient, and intravesicular pH.

Glutamate, the major excitatory neurotransmitter in the mammalian central nervous system, is transported into bovine synaptic vesicles in a manner that is ATP dependent and requires a vesicular electrochemical proton gradient. We studied the electrical and chemical elements of this driving force and evaluated the effects of chloride on transport. Increasing concentrations of Cl- were found to increase the steady-state ATP-dependent vesicular pH gradient (delta pH) and were found to concomitantly decrease the vesicular membrane potential (delta psi). Low millimolar chloride concentrations, which cause 3-6-fold stimulation of vesicular glutamate uptake, caused small but measurable increases in delta pH and decreases in delta psi, when compared to control vesicles in the absence of chloride. Nigericin in potassium buffers was used to alter the relative proportions of delta pH and delta psi. Compared to controls, at all chloride concentrations tested, nigericin virtually abolished delta pH and increased the vesicle interior positive delta psi. Concomitantly, nigericin increased ATP-dependent glutamate uptake in 0-1 mM chloride but decreased glutamate uptake in 4 mM (45%), 20 mM (80%), and 140 mM (75%) Cl- (where delta pH in the absence of nigericin was large). These findings suggest that either delta psi, delta pH, or a combination can drive glutamate uptake, but to different degrees. In the presence of 4 mM Cl-, where uptake is optimal, both delta psi and delta pH contribute to the driving force for uptake. When the extravesicular pH was increased from 7.4 to 8.0, more Cl- was required to stimulate vesicular glutamate uptake. In the absence of Cl-, as extravesicular pH was lowered to 6.8, uptake was over 3-fold greater than it was at pH 7.4. As extravesicular pH was reduced from 8.0 toward 6.8, less Cl- was required for maximal stimulation. Decreasing the extravesicular pH from 8.0 to 6.8 in the absence of Cl- significantly increased glutamate uptake activity, even though proton-pumping ATPase activity actually decreased about 45% under identical conditions. In the absence of chloride, nigericin increased glutamate uptake at all the pH values tested except pH 8.0. Glutamate uptake at pH 6.8 in the presence of nigericin was over 6-fold greater than uptake at pH 7.4 in the absence of nigericin. We conclude from these experiments that optimal ATP-dependent glutamate uptake requires a large delta psi and a small delta pH.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenosine Triphosphate↗
PubMed1992

Phenotypical characteristics of acute myelocytic leukemia associated with the t(8;21)(q22;q22) chromosomal abnormality: frequent expression of immature B-cell antigen CD19 together with stem cell antigen CD34.

Twenty-three acute myelocytic leukemia (AML) patients with t(8;21) chromosomal abnormality, all classified as M2 (French-American-British [FAB] classification), were investigated. Blastic cells from all patients were positive for the stem cell-associated antigens, CD34 and HLA-DR, and the immature myeloid antigens, CD13 and CD33. The nonblastic leukemic cells expressed the more mature myeloid antigens, CD11b and CD15, with loss of the immature phenotype. The incidence of positivities for the stem cell-associated antigens, CD34 and HLA-DR, in t(8;21) AML cells was significantly higher in comparison with those in other AML showing granulocytic differentiation (M2 or M3). AML cells with t(8;21) also showed some phenotypic abnormalities. Frequent expression of CD19 was found in the blastic population of t(8;21) AML (18 of 23 cases) without other B-cell antigens and Ig gene rearrangements. CD19 expression was confirmed by immunocytochemistry and Northern blotting. The CD19+ blastic cells coexpressed both CD34 and HLA-DR. In addition, CD33+ cells among the blastic fraction in t(8;21) AML cells were fewer in number than in those of M2 or M3 AML without t(8;21). Our findings indicate that leukemic blasts of t(8;21) AML commonly express CD19 while preserving the stem cell-associated antigens, and differentiate into the granulocytic pathway with discordant maturation such as low CD33 expression.

Adult↗
PubMed1992

[Experimental study on the usefulness of the autoperfusion balloon catheter in maintaining the blood supply to the distal organs].

Autoperfusion Balloon Catheters (APBC) were inserted into the renal arteries of seven dogs for about two and a half hours. Abdominal aortography showed renal arterial flow of the kidney obstructed by APBC. Macroscopic and microscopic examination revealed no significant changes in the resected specimen. It is concluded that APBC is useful in cases of proximal arterial occlusion by maintaining the blood supply to the distal organs for relatively short periods and that it can be used for the treatment of rupture of arteries which feed critical organs.

Animals↗
PubMed1992

The T-loop region of animal mitochondrial tRNA(Ser)(AGY) is a main recognition site for homologous seryl-tRNA synthetase.

Recognition sites of bovine mitochondrial serine tRNA specific for condons AGY [tRNA(Ser) (AGY)] by the cognate mitochondrial seryl-tRNA synthetase were studied using a range of tRNA(Ser)(AGY) variants which were obtained by the in vitro transcription of synthetic tRNA genes with T7 RNA polymerase. Base replacements in the anticodon and discriminator sites did not affect serine acceptance. However, deletion and/or replacement in the T-loop region completely deprived the variants of their charging activities. Point mutation experiments in this region also showed that the adenosine residue in the middle of the T-loop (position 58), which is involved in tertiary interaction between the T-loop and the truncated D-arm [de Bruijn and Klug, 1983] played a significant role in the recognition process by the synthetase.

Animals↗
PubMed1992

The synthesis and properties of oligodeoxyribonucleotides containing N6-methoxyadenine.

Oligodeoxyribonucleotides containing N6-methoxyadenine (M) have been synthesized. The order of stability of duplexes consisting of synthesized oligodeoxyribonucleotides, 5'd(CCTGGTAXCAGGTCC)3'-5'd(GGACCTGNTACCAGG)3' (X = M, A, G. N = A, G, T, C), was M: A (Tm = 52 degrees C) greater than M: T (50 degrees C) greater than M: G (48 degrees C) greater than M: C (46 degrees C) observed by thermal denaturation in a buffer of 0.01 M Na cacodylate, and 0.1 M NaCl at pH 7.0. The Tms are within a range of 6 degrees of difference, which is smaller than those of Tms of the duplexes containing A:N pairs (11 degrees) and G:N pairs (11 degrees). DNA replication study on a template-primer system, 5'd(32p-CAGCTTTCGC)3' 3'd(GTCGAAAGCGMAGTCG)5', showed that TTP and dCTP were incorporated into DNA strands at a site opposite to M by Klenow DNA polymerase, but dATP and dGTP were not.

Adenine↗
PubMed1992

Detection of hepatitis C virus antibody in the absence of viral RNA in patients with autoimmune hepatitis.

OBJECTIVE: To determine whether laboratory findings showing antibodies to hepatitis C virus (HCV) in patients with autoimmune hepatitis represent false-positive results and to identify possible explanations for true-positive results in these patients. DESIGN: Cross-sectional. SETTING: University-based hospital. PATIENTS: Fifty-two patients with non-A, non-B chronic hepatitis as a control group and 26 patients with classic chronic active autoimmune hepatitis. MEASUREMENTS: Comparison of the results of five kinds of assays of HCV antibodies and HCV RNA. MAIN RESULTS: Of 52 patients with non-A, non-B chronic hepatitis, HCV antibodies (anti-HCV) were detected in 42 patients (81%; 95% CI, 67% to 90%) by a first-generation enzyme-linked immunosorbent assay (ELISA-I), in 39 patients (75%) by Sp42 ELISA, in 37 patients (71%) by RIA-I, in 49 patients (94%) by ELISA-II, and in 48 patients (92%) by RIBA-II. We found HCV RNA in 47 patients (90%; CI, 79% to 97%). Of the 26 patients with autoimmune hepatitis, anti-HCV were detected in 23 patients (88%; CI, 70% to 98%) by ELISA-I, in 12 (46%) by both RIA-I and Sp42 ELISA, in 20 (77%) by ELISA-II, and in 9 (35%) by RIBA-II. However, HCV RNA was found in only five of these patients (19%; CI, 7% to 39%). None of our patients, including controls, had antibodies to superoxide dismutase. Of the 21 patients who had autoimmune hepatitis that was completely responsive to steroid therapy, 18 had anti-HCV by ELISA-I, but 13 of these patients had negative results by RIBA-II, and only two patients had HCV RNA. Of the five patients who did not respond to steroid treatment, all had anti-HCV by ELISA-I, four had negative results by RIBA-II, and three had HCV RNA. CONCLUSIONS: Testing for HCV antibodies in patients with autoimmune hepatitis frequently elicits positive results when the ELISA-I or ELISA-II tests are used. Most of these appear to represent false-positive results because HCV RNA is usually absent from the serum. Such false positivity may result from previous infection with HCV or from cross-reaction of an epitope of HCV. Other patients with apparent autoimmune hepatitis who fail to respond to corticosteroid therapy may actually have chronic hepatitis C (or other non-A, non-B hepatitis) infection.

Adult↗
PubMed1992

A new cdc gene required for S phase entry of Schizosaccharomyces pombe encodes a protein similar to the cdc 10+ and SWI4 gene products.

We have isolated a new cell division cycle gene (res1+) required for entry into S phase, as a multicopy dual suppressor of the pat1 and cdc10 mutants of the fission yeast Schizosaccharomyces pombe. The res1+ gene specifies a 72 kDa protein with two copies of the cdc10/SWI6 motif. A disruptant of res1+ grows poorly at 30 degrees C with severe heat- and cold-sensitivities, and completely arrests in G1 at 36 degrees C and 23 degrees C. The arrested disruptant retains a full conjugation ability. In addition to the cdc10/SWI6 motif, Res1 and SWI4 proteins share a remarkable homology in their amino-terminal region, whereas Cdc10 and SWI6 do so in their carboxy-terminal region. Moreover, the amino-terminal region is essential for the function of Res1 as it is for the function of SWI4. Furthermore, analogous to the relationship of SWI4 to SWI6, the res1+ gene effectively rescues cdc10 mutants, but the cdc10+ gene cannot rescue the res1- phenotype. Thus, striking similarities exist in both structural and functional relationships between Res1 and SWI4, and between Cdc10 and SWI6. In view of the fact that SWI4 and SWI6 form a transcription factor complex and activate promoters containing the SWI4/SWI6 dependent cell-cycle box, Res1 might be a putative association partner of Cdc10 which appears to be involved at least in the activation of promoters containing a MluI cell-cycle box.

Amino Acid Sequence↗
PubMed1992

Hemocompatibility of human whole blood on polymers with a phospholipid polar group and its mechanism.

The hemocompatibility of a polymer containing a phospholipid polar group, poly(2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate(BMA)), with human whole blood was evaluated. When human whole blood without an anticoagulant was contacted with polymers, the blood cell adhesion and aggregation on the polymer without the MPC moiety was extensive, and considerable fibrin deposition was observed. This phenomenon was suppressed with an increase in the polymer MPC composition. Thus, the MPC moiety in the copolymer plays an important role in the nonthrombogenic behavior of the copolymer. These results were also confirmed by the whole blood coagulation time on the polymer surface which was determined by Lee-White method. The adsorption of phospholipids and proteins from human plasma on poly(MPC-co-BMA) was investigated to clarify the mechanism of the nonthrombogenicity observed with the polymer. The amount of phospholipids was increased; whereas, adsorbed proteins were decreased with an increase in the MPC composition. From these results, we concluded that the phospholipids adsorbed on poly(MPC-co-BMA) play the most important role in the nonthrombogenicity of the MPC copolymer.

Adsorption↗
PubMed1992

Adjuvant chemotherapy with early intravesical instillation of adriamycin and long-term oral administration of 5-fluorouracil in superficial bladder cancer. The Kyushu University Urological Oncology Group.

A randomized controlled trial was performed to study the efficiency of adjuvant chemotherapy with early intravesical instillation of Adriamycin and long-term oral administration of 5-fluorouracil in 275 patients with superficial bladder cancer. All of the patients were randomized into four groups. Group A received early (immediately and 2 days after transurethral resection) instillation of Adriamycin alone; Group B received early instillation of Adriamycin with oral administration of 5-fluorouracil; Group C received delayed (7 days after transurethral resection) instillation of Adriamycin alone; and group D received delayed instillation of Adriamycin with oral administration of 5-fluorouracil. All patients subsequently received instillations weekly for 2 weeks and then every 2 weeks for a further 14 weeks. After 4 months, they received monthly instillations for 8 months. 5-Fluorouracil (groups B and D) was given daily p.o. for 1 year. Evaluation was possible in 187 patients. The postoperative follow-up period for determination of non-recurrence rates was 36 months, during which no significant difference was detected among the four groups. Moreover, no statistically significant difference was found between the early- and delayed-instillation groups. However, the non-recurrence rates obtained in the groups undergoing early instillation were higher than those determined in the delayed-instillation groups during the 36-month follow-up period, and this difference was especially significant at 4 and 5 months. In addition, the early-instillation groups showed significantly higher non-recurrence rates than did the delayed-instillation groups in terms of primary cases (P less than 0.01), tumor size of less than 1 cm (P less than 0.05), multiple tumors (P less than 0.01), pathological stage pTa (P less than 0.01), and histological grades G1 and G2 (P less than 0.05). Groups B and D, which were treated by intravesical instillation of Adriamycin with oral administration of 5-fluorouracil, showed no significant prophylaxis of recurrence during the 36-month follow-up as compared with groups A and C, which received intravesical instillations alone. The main side effect, which required discontinuation of the treatment, was bladder irritation. However, no significant difference in its incidence was found between the early- and delayed-instillation groups. No severe systemic side effect was encountered in this study. These results suggest that early as well as repeated intravesical instillation of Adriamycin is clinically tolerable and may be effective in preventing the recurrence of superficial bladder cancer.

Administration, Intravesical↗
PubMed1992

Calcium blockers enhance cisplatin-induced nephrotoxicity in rats.

To examine the effects of calcium blockers on nephrotoxicity caused by cisplatin, the renal function and renal accumulation of Pt in Sprague-Dawley rats given 6.5 mg/kg i.v. cisplatin simultaneously with several doses of verapamil or nicardipine were evaluated. BUN, serum creatinine and kidney Pt concentrations in rats given more than 5.0 mg/kg of verapamil were significantly higher than those of the control animals injected with 6.5 mg/kg i.v. cisplatin alone, and the increase of each value was dependent upon the dose of verapamil. BUN, creatinine and kidney Pt in rats injected with more than 0.5 mg/kg i.p. nicardipine were also significantly higher than those of the controls. Calcium blockers enhanced the renal accumulation of Pt and the nephrotoxicity of cisplatin.

Animals↗
PubMed1992

Generation of lysoglyceroglycolipids in the cyanobacterium, Phormidium tenue.

Two kinds of lysoglycolipids, monogalactosyl 1-monoacylglycerol and digalactosyl 1-monoacylglycerol were generated in the cyanobacterium, Phormidium tenue, when it was stored at -20 degrees for more than 1 month. By comparison of the compositions of fatty acid residues between monogalactosyl 1-monoacylglycerol and monogalactosyl diacylglycerol, digalactosyl 1-monoacylglycerol and digalactosyl diacylglycerol, respectively, the 1-monoacylgalactolipids were presumed to be formed by regioselective deacylation at the sn-1 position with subsequent acyl-group migration from the sn-2 to the sn-1 position. In contrast, 1-monoacyl derivatives of sulphoquinovosyl diacylglycerol and phosphatidylglycerol, the other membrane lipids contained in cyanobacteria, were not formed.

Carbohydrate Sequence↗
PubMed1992

Immediate type of allergy in statis growers.

Three statis growers complaining of immediate allergic symptoms induced by harvesting statis in a plastic greenhouse were examined to clarify their allergic conditions. Distinct positive reactions in the intradermal test and nasal and eye provocation test to the statis extracts were shown in all three cases. High score of radioallergosorbent test (RAST) IgE and remarkable RAST inhibitory effects to the statis extracts were seen in these cases. The immunologic cross-reactivity between statis and chrysanthemum was absent in the RAST inhibition in the patient labeled case C who had complained of the same allergic symptoms when handling chrysanthemums in the off-season for harvesting statis. Those results indicated that the allergic conditions of the present cases were from an immediate type of allergy mediated by a specific IgE antibody to the statis extract.

Adult↗