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T Usui

Publications and source records attributed to T Usui.

At least 217 records · Page 12Linked to original sources
PubMed1996

Age associated changes in the distribution of lpr gene-induced B220-positive T cells in lymphoid organs of MRL/Mp-lpr/lpr mice using dual exposure microphotographs of double immunofluorescence staining.

Homozygous MRL/Mp-lpr/lpr [MRL/lpr] mice, which have an autosomal recessive mutant lpr gene and exhibit defects in Fas antigen, spontaneously develop autoimmune disease with progressive expansion and accumulation of characteristic abnormal CD4-CD8-double negative T cells that express B220 surface antigen, a B cell-specific surface marker in normal mice. We analyzed the distribution and age related changes of lpr gene-induced abnormal T cells (B220-positive lpr T cells) in the lymphoid organs of MRL/lpr mice. We studied cryostat sections of the spleen, peripheral lymph nodes, mesenteric lymph nodes, and Peyer's patches at different stages using FITC [fluorescein isothiocyanate)-conjugated monoclonal antibodies directed against B220 (RA3-6B2) and PE (phycoerythrin)-conjugated anti-mouse CD3 (2C11) monoclonal antibody, examining dual-exposure microphotographs of double-immunofluorescence stained preparations. We observed that in aged MRL/lpr mice, B220-positive abnormal lpr T cells were not present in the thymus-dependent area, and the majority of the follicular area cells were displaced by lpr T cells. These findings suggest that the cellular trafficking of B220-positive lpr T cells differs from that of conventional T cells and that these lpr-derived T cells play a role in the follicle.

Aging↗
PubMed1996

[Usefulness of bladder auto-augmentation in neurogenic bladder: a case report].

A 41-year-old male with myelomenigocele underwent a bladder auto-augmentation and endoscopic collagen injections. He has been performing self intermittent catheterization for 10 years but urinary incontinence remained unchanged. Furthermore, he suffered from recurrent pyelonephritis due to the left vesicoureteral reflux. A preoperative fluoroscopic urodynamic study showed a poorly compliant bladder with the maximal bladder capacity of 200 ml at 60 cmH2O. The left vesicoureteral reflux was observed at 10 cmH2O. The low compliant bladder was treated with the bladder autoaugmentation and the left vesicoureteral reflux was treated with the endoscopic subureteral injection of collagen 5 months after the previous operation. A fluoroscopic urodynamic study 6 months postoperatively showed the increase of the maximal bladder capacity of 300 ml at 18 cmH2O and the reflux disappeared completely. The endoscopic periurethral injections of collagen improved his persisting urinary incontinence. In patient with neurogenic bladder having a lot of clinical problems, bladder auto-augmentation is less invasive and offers many advantages over enterocystoplasy.

Adult↗
PubMed1996

Inhibition of mouse tumor metastasis with nojirimycin-related compounds.

The antimetastatic activity of ten compounds structurally related to nojirimycin A was examined using a pulmonary metastatic model of mouse B16 melanoma. Nojirimycin B, deoxynojirimycin, D-gluco-delta-lactam, CP3068 and CP3069 are structural analogues of nojirimycin A, and showed potent or moderate antimetastatic activities. Nojirimycin A, nojirimycin B, deoxynojirimycin and D-gluco-delta-lactam showed potent or moderate inhibitory activities against alpha-glucosidase, beta-glucosidase and beta-mannosidase, but CP3068 and CP3069 in which the structures were related to D-gluco-delta-lactam showed no inhibitory activities. CP3041, CP3042, CP3043, CP3045 and CP3048 are analogues of sodium D-glucaro-delta-lactam (ND2001), a carboxy derivative of nojirimycin A, and showed potent or moderate antimetastatic activities. But no analogue was superior to ND2001 concerning with antimetastatic and anti-beta-glucuronidase activities. CP3041 and CP3042 showed potent and moderate inhibitory activities against beta-glucuronidase, respectively, but CP3043, CP3045 and CP3048 showed little or no activities.

1-Deoxynojirimycin↗
PubMed1996

Electroretinographic campimetry in a patient with crystalline retinopathy.

We report the findings we obtained by multifocal electroretinography (ERG) in a patient with crystalline retinopathy. Although the conventional Ganzfeld (full-field) ERG was within the normal range, the amplitudes were reduced and implicit times were delayed in the parafoveolar region in the multifocal ERG. To our knowledge, this is the first report on crystalline retinopathy investigated with this spatially differentiating electrophysiologic method, which is useful for the detection of early change in this disease.

Adult↗
PubMed1995

A K-252a-resistance gene, sks1+, encodes a protein similar to the Caenorhabditis elegans F37 A4.5 gene product and confers multidrug resistance in Schizosaccharomyces pombe.

A gene named sks1+ was cloned as a suppressor of the K-252a-sensitivity phenotype of Schizosaccharomyces pombe (Sp) from a gene library of the parental Sp chromosomal DNA constructed with a multicopy vector pDB248'. The gene encoded a 308-amino-acid (aa) protein similar to the Caenorhabditis elegans F37 A4.5 gene product and to the mouse and Drosophila Mov34 gene products. The sks1+ null mutants obtained by gene disruption were non-viable, indicating that sks1+ is essential for vegetative growth. The parental Sp strain carrying multiple copies of sks1+ showed distinct cross-resistance to staurosporine, thiabendazole and vanadate in addition to K-252a, although Sks1 has no similarity in aa sequence to those of ATP-binding cassette (ABC)-type transporters. The multicopy plasmid containing sks1+ conferred multidrug resistance (MDR), even in a mutant cell defective in pmd1+ encoding an ABC-type transporter. It is therefore unlikely that the function of pmd1+ is involved in MDR conferred by sks1+. These results suggest that sks1+ is a functionally novel MDR gene.

Amino Acid Sequence↗
PubMed1995

Structural organization and chromosomal assignment of the human prostacyclin receptor gene.

Prostacyclin receptor is a member of the prostanoid receptor family in the G protein-coupled receptor superfamily with seven transmembrane domains. We report here the isolation and structural organization of the human prostacyclin receptor gene. Southern blot analysis demonstrated a single copy of the human prostacyclin receptor gene in the human genome. The human prostacyclin receptor gene spanned approximately 7.0 kb and was composed of three exons separated by two introns. The first intron occurred in the 5'-untranslated region, 13 bp upstream to the ATG start codon. The second intron was located at the end of the sixth transmembrane domain, thereby separating it from the downstream coding region and the 3'-untranslated region. By primer extension analysis, the transcription initiation sites were mapped 870-872 bp upstream to the ATG start codon. The 1.2-kb human prostacyclin receptor 5'-flanking region lacked conventional TATA and CCAAT boxes, but it contained several cis-acting regulatory elements including an inverted CCAAT box (Y box) and two copies of SP-1 binding sites. Using human-rodent somatic hybrid cell DNA, the human prostacyclin receptor gene was assigned to human chromosome 19. The present study helps establish the genetic basis for prostacyclin receptor research and provides further insight into the molecular mechanisms underlying the prostanoid receptor family.

Amino Acid Sequence↗
PubMed1995

Enzymic synthesis of lacto-N-triose II and its positional analogues.

N-acetylhexosaminidase from Nocardia orientalis catalysed the synthesis of lacto-N-triose II glycoside (beta-D-GlcNAc-(1-3)-beta-D-Gal-(1-4)-beta-D-Glc-OMe, 3) with its isomers beta-D-GlcNAc-(1-6)-beta-D-Gal-(1-4)-beta-d-Glc-OMe (4) and beta-D-Gal-(1-4)-[beta-D-GlcNAc-(1-6)]-beta-D-Glc-OMe (5) through N-acetylglucosaminyl transfer from N,N'-diacetylchitobiose (GlcNAc2) to methyl beta-lactoside. The enzyme formed the mixture of trisaccharides 3, 4 and 5 in 17% overall yield based on GlcNAc2, in a ratio of 20:21:59. With p-nitrophenyl beta-lactoside as an acceptor, the enzyme also produced p-nitrophenyl beta-lacto-N-trioside II (beta-D-GlcNAc-(1-3)-beta-D-Gal-(1-4)-beta-D-Glc-OC6H4NO2-p, 6) with its isomers beta-D-GlcNAc-(1-6)-beta-D-Gal-(1-4)-beta-D-Glc-OC6H4NO2-p (7) and beta-D-Gal-(1-4)-[beta-D-GlcNAc-(1-6)]-beta-D-Glc-OC6H4NO2-p (8). In this case, when an inclusion complex of p-nitrophenyl lactoside acceptor with beta-cyclodextrin was used the regioselectivity of glycosidase-catalysed formation of trisaccharide glycoside was substantially changed. It resulted not only in a significant increase of the overall yield of transfer products, but also in the proportion of the desired compound 6.

Carbohydrate Conformation↗
PubMed1995

Gene expression of prostacyclin receptor in the hypertrophied heart of spontaneously hypertensive rats.

1. Prostacyclin elicits potent vasodilation and inhibition of platelet aggregation through binding to its membrane receptor. The impairment of prostacyclin receptor activity is implicated in various human cardiovascular diseases. We recently succeeded in molecular cloning of cDNA for the mouse, rat, and human prostacyclin receptors. 2. In the present study, we examined the mRNA expression of the prostacyclin receptor in various rat tissues, and further investigated its gene expression in the hypertrophied cardiac ventricles of stroke-prone spontaneously hypertensive rats (SHRSP). 3. In rat tissues, a single RNA band of approximately 3.7 kb was detected by northern blotting analysis using rat prostacyclin receptor cDNA as a probe. In adult Wistar rats, abundant mRNA expression was observed in the aorta, lung and spleen. Substantial amounts of transcript were expressed in the heart, pancreas, thymus and stomach. In contrast, no mRNA expression was detected in the brain. 4. We further examined the mRNA expression of the prostacyclin receptor in the ventricles of 21 week old SHRSP. The ventricles of SHRSP showed remarkable hypertrophy, compared with those of age-matched Wistar-Kyoto (WKY) rats. The expression of prostacyclin receptor mRNA in the hypertrophied ventricles of SHRSP was almost equivalent to that in the ventricles of WKY. 5. The present study revealed the gene expression of the prostacyclin receptor in various rat tissues, and further demonstrated the receptor mRNA expression in hypertensive cardiac hypertrophy. The present study will give a clue to investigate the clinical implication of prostacyclin and its receptor.

Animals↗
PubMed1995

Pulmonary nodules in patients with a history of radical nephrectomy for renal cell carcinoma.

BACKGROUND: Nine patients with a history of radical nephrectomy for renal cell carcinoma underwent surgical removal of newly detected pulmonary nodules at the Hiroshima University Hospital. Six patients had metastatic lung tumors two patients had bronchogenic primary carcinomas and one had a granulomatous infection. METHODS: To determine if any characteristics can distinguish a new primary carcinoma from metastatic renal cell carcinoma, we reviewed the nine patients described above. The patients with pulmonary metastases and those with new primary lung cancers did not differ in age, sex, history of smoking, clinical stage and pathological findings of the renal primary site, on the location and size of the pulmonary nodules. RESULTS: Only the interval between the nephrectomy and the appearance of the new pulmonary lesion may be a predictive factor. This interval was 48 and 51 months for the patients with new primary lung cancers but varied from 0 to 39 months for the patients with metastatic renal cell carcinoma. A solitary nodule had an equal chance of being metastatic or primary. CONCLUSIONS: These results indicate that a solitary nodule that is detected at a longer interval after radical nephrectomy may be a new primary lung cancer. Once new pulmonary nodules are identified in a patient with a history of radical nephrectomy for renal cell carcinoma, surgical excision is required for a final diagnosis before initiating therapy for metastases.

Adult↗
PubMed1995

Long-term results with M-VAC for advanced urothelial cancer: high relapse rate and low survival in patients with a complete response.

OBJECTIVE: To describe the long-term results of treating patients with advanced urothelial cancer using a combination of methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC). PATIENTS AND METHODS: Fifty-one patients (37 men and 14 women, median age 66 years, range 41-82) with inoperable or metastatic carcinoma of the bladder, ureter or renal pelvis were treated with M-VAC and their responses evaluated for up to 7 years. Relative dose intensity (RDI) was calculated by dividing the actual dose intensity by the projected total dose intensity and related to outcome. Overall survival was assessed from the date of initiation of treatment with M-VAC, using the Kaplan-Meier method. RESULTS: Of the 51 patients. 10 (20%) had a complete and 18 (35%) had a partial response, giving an overall response rate of 55% (95% CI, 41-68%). There was no significant difference in the median values of RDIs with response to the M-VAC regimen. The median duration of response was 11.9 months for the 10 patients with a complete response and of these, eight relapsed at a median of 10 months after treatment and died at a median of 8.5 months from the time of disease recurrence. Survival of patients with a complete response differed significantly from those with no response at 1 year after the start of treatment, but not subsequently. CONCLUSION: Long-term follow-up revealed a high relapse rate and poor prognosis in patients with a complete response who received the M-VAC as induction therapy. Therefore, new adjunctive therapies are needed for patients with locally unresectable or metastatic urothelial cancer.

Adult↗
PubMed1995

Trends in antimicrobial resistance of Streptococcus pneumoniae in Japan.

A total of 184 isolates of Streptococcus pneumoniae were recovered from the sputa of patients over a 5-year period in the Nagasaki area and were examined. A total of 30 strains were resistant to penicillin (MIC, > or = 0.10 micrograms/ml), 13 of which belonged to serotype 19B. These strains showed decreased susceptibility to other antimicrobial agents. Vancomycin, cefpirome, and imipenem were the most active agents tested.

Anti-Bacterial Agents↗
PubMed1995

Preliminary results of methotrexate, etoposide and cisplatin in the treatment of urothelial cancer.

Thirty-seven patients with urothelial cancer were given combination chemotherapy with methotrexate, etoposide and cisplatin. Thirty patients were evaluated for response. Response rates were 50% in the primary organ, 50% in the lymph nodes, 0% in lung and bone lesions. Two patients (7%) had a complete response and 12 (40%) had a partial response, for an overall response rate of 47%. The overall response rate rose to 57% in 7 patients treated with escalated doses of methotrexate and cisplatin. The median durations of response were 14 months for complete responders and 16 months for partial responders. Of the 30 evaluable patients, 16 (53%) are alive at a median survival of 30 months. The toxicity of the present regimen was acceptable. The methotrexate-etoposide-cisplatin combination chemotherapy seems to be an effective and safe regimen for urothelial cancer.

Adenocarcinoma↗
PubMed1995

Neoadjuvant chemotherapy for locally advanced urothelial cancer of the upper urinary tract.

Cisplatin-based multiple-drug chemotherapy is currently considered the most effective treatment for advanced and metastatic urothelial cancers. We treated 15 patients with locally advanced urothelial cancers of the upper urinary tract using the cisplatin-based multiple-drug regimen in a neoadjuvant setting. The regimens administered were: M-VAC (methotrexate, vinblastine, doxorubicin and cisplatin); MEC (methotrexate, etoposide and cisplatin), or M-VEC (methotrexate, vinblastine, epirubicin and cisplatin). Total nephroureterectomy was performed in all patients and response was evaluated pathologically Of 15 patients 2 (13%) achieved a pathological complete response, 6 (40%) a pathological partial response, for an overall response rate of 53% (95% confidence limits 29-77%). The median durations of response were 54 months for patients with a pathological complete response and 15.5 months for patients with a pathological partial response. One of six patients with a pathological partial response and 4 of 7 with no remission died of cancer. While a positive relationship between the pathological response and prognosis was observed, adequate follow-up is needed to assess the ability of neoadjuvant chemotherapy to improve the prognosis of patients with locally advanced urothelial cancer of the upper urinary tract.

Adenocarcinoma↗
PubMed1995

Phosphatidylinositol-3 kinase in fission yeast: a possible role in stress responses.

A DNA fragment coding for a part of a putative phosphatidylinositol 3 kinase was cloned from Schizosaccharomyces pombe by cross-hybridization with Saccharomyces cerevisiae VPS34 gene, a yeast homologue of mammalian PI-3 kinase. The clone contained an open reading frame of 797 amino acids but lacked the initiation codon, ATG. The predicted amino acid sequence was homologous to those of S. cerevisiae VPS34 and mammalian PI-3 kinase genes. Disruption of the gene resulted in extremely low levels of PI-3-P and higher levels of PI-4-P, supporting the idea that the gene codes for the PI-3 kinase of S. pombe. The disruptants harbored large vacuoles and were sensitive to stresses such as high temperature or high concentration of monovalent and divalent cations.

Amino Acid Sequence↗