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Y Osada

Publications and source records attributed to Y Osada.

At least 19 recordsLinked to original sources
PubMed1995

Cloning of the cDNA encoding a novel rat mast-cell proteinase, rMCP-3, and its expression in comparison with other rat mast-cell proteinases.

A cDNA encoding a novel rat mast-cell proteinase (MCP) named rMCP-3 was successfully cloned and sequenced from the peritoneal cells of Lewis rats infected with the intestinal nematode Nippostrongylus brasiliensis by using the combination of reverse transcription-PCR and rapid-amplification-of-cDNA-ends ('RACE') methods. The cDNA was 979 bp long and included a 741 bp open reading frame. When the deduced amino acid sequence was compared with those of other known mast-cell proteinases, rMCP-3 was considered to be translated as a preproenzyme with a 19-amino-acid signal peptide, a two-amino-acid activation peptide and a 226-amino-acid mature enzyme. The amino acid identity in the mature enzyme was 52.9% and 55.1% with rMCP-1 and rMCP-2 respectively. The rMCP-3 mRNA was not detected in the peritoneal cells of mast-cell-deficient Ws/Ws rats, though it was strongly detected in those of littermate +/+ and Lewis rats, indicating the mast-cell origin of rMCP-3 In addition to being present in peritoneal mast cells, the rMCP-3 mRNA was strongly detected in the skin, tongue, and RBL2H3 rat basophilic leukaemia cells and weakly in the jejunum of N. brasiliensis-infected rats by RNA blot analysis using a rMCP-3 gene-specific probe. By reverse transcription-PCR, the rMCP-3 mRNA was also detected in the lung. While the expression of rMCP-1 and rMCP-2 are clearly restricted in connective-tissue mast cells and mucosal mast cells respectively, rMCP-3 was widely expressed in both types of mast cells with a predominance in connective-tissue mast cells.

Amino Acid Sequence↗
PubMed1995

Cloning of multidrug resistance gene pqrA from Proteus vulgaris.

The multiple antibiotic resistance gene pqrA was cloned from the chromosomal DNA of a clinical isolate of Proteus vulgaris 881051 into Escherichia coli KY2563. The MICs of quinolones tetracycline, cephalosporin, and chloramphenicol for transformant strain DNS7020 were from 8 to 32 times higher than those for the parent strain, KY2563. The level of expression of outer membrane protein F (OmpF) by DNS7020 was lower than that of KY2563 but not as low as that of an OmpF-deficient control strain. The 1.4-kb fragment containing the pqrA gene had an open reading frame encoding a polypeptide of 122 amino acid residues with a molecular weight of about 14,000, which was consistent with the experimental value identified by the Maxicell method. The putative PqrA polypeptide showed significant amino acid sequence similarity to the E. coli proteins SoxS and MarA. These polypeptides are strongly conserved in predicted helix-turn-helix DNA binding domains. The MarA protein, which is responsible for multiple antibiotic resistance in E. coli, also decreases OmpF expression. Moreover, the SoxS protein, which is characterized as a superoxide response regulon of E. coli, has also been shown to increase resistance to many structurally unrelated antibiotics. The soxS gene increases superoxide dismutase levels in addition to decreasing OmpF expression. The expression level of superoxide dismutase with DNS7020 was about 1.5 times higher than that with KY2563. These findings suggest that the pqrA gene in P. vulgaris confers multidrug resistance in a way similar to that of the soxS and marA genes in E. coli.

Amino Acid Sequence↗
PubMed1995

[Treatment of advanced renal cell carcinoma with a combination of interferon alpha and gamma].

A total of 29 patients with advanced renal cell carcinoma entered a pilot study of combination therapy with interferon alpha (IFN-alpha) and interferon gamma (IFN-gamma). IFN-alpha (HLBI: 3 x 10(6) IU, BALL 1:5 x 10(6) IU, IFN-alpha-2a: 9 x 10(6) IU or IFN-alpha-2b: 6 x 10(6) IU) was given intramuscularly every day and IFN-gamma (IFN-gamma-1a: 3 x 10(6) JRU) was given intravenously by drip infusion 3 times a week (every 2-3 days). The treatment was continued for 3 months as the induction therapy, and then the tumor response was evaluated. Of the 22 evaluable patients, 4 achieved a partial response (PR), 10 showed no change (NC), and in 8 the disease had progressed (PD) during the therapy. Thus, the overall response rate was 18.2% [95% confidence interval (CI) 2.1-34.3%]. A favorable response tended to be obtained in patients with good performance status or small pulmonary metastases, or in those who had no prior therapy with IFN-alpha, who received this treatment immediately subsequent to radical nephrectomy, or who received IFN-gamma as much as possible according to this regimen. Toxicity was evaluated in 28 patients: fever, general fatigue, anorexia, leukocytopenia and impaired liver function were frequently noted, and 3 patients were withdrawn from the study because of such adverse effects. In patients who had a PR or NC, the same dosage of IFN-alpha was continued to be given intramuscularly 2-3 times a week (every 2-4 days) as the maintenance therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Establishment and characterization of a human renal carcinoma cell line MRT-1, with special reference to the production of serine proteinase inhibitors.

A new human cell line MRT-1 was established from a metastatic lymph node of renal cell carcinoma of a 47 years old Japanese male. The cultured MRT-1 cells exhibit an epithelial appearance and contain lipid vacuoles in their cytoplasm in vitro. The modal chromosome number was 70. Doubling time and plating efficiency were 32.5 h and 5%, respectively (at the 47th passage). Injection of 1X10(6) MRT-1 cells beneath the renal capsule of nude mice resulted in tumor formation resembling the original tumor. Serine proteinase inhibitors produced by the cell line were analyzed. The cultured cells produced alpha 1-antitrypsin (alpha 1-AT) and plasminogen activator inhibitor-1 (PAl-1) into the conditioned medium. Most of the MRT-1 derived alpha 1-AT had lost the affinity to Concanavalin A when compared to the normal plasma alpha 1-AT.

Animals↗
PubMed1994

Relationship between serum prostate specific antigen and histological prostatitis in patients with benign prostatic hyperplasia.

The relationship between the serum values of prostate specific antigen (PSA) and the extent of histological prostatitis was investigated in 42 patients undergoing transurethral resection of the prostate for benign hyperplasia (BPH) without clinical evidence of prostatitis. Histological prostatitis was divided into three groups: acute, chronic-active, and chronic-inactive inflammation. The extent of histological prostatitis was expressed as the number of prostatic acinar and ductal glands with inflammatory infiltrate per total number of glands (%). The serum PSA values significantly correlated with the extent of acute and chronic-active prostatitis (correlation coefficient r = 0.765 and 0.656, P < 0.01). A relationship between PSA values and the extent of chronic-inactive prostatitis was not found. In the immunohistochemical study, prostatic epithelial cells with acute and chronic-active inflammation showed negative staining for PSA antigen. These results indicate that histological acute and chronic-active prostatitis is considered an important factor for inducing the high increase in serum PSA values via the leak phenomenon.

Aged↗
PubMed1994

Anti-angiogenesis agent DS-4152 is a potent and selective inhibitor of HIV-1 replication in vitro.

OBJECTIVE: To determine whether the anti-angiogenesis agent DS-4152 inhibits the replication of HIV-1 in vitro. DESIGN: A sulfated polysaccharide-peptidoglycan DS-4152 has recently been identified as a potent and selective inhibitor of Kaposi's sarcoma (KS). Therefore, it is important to evaluate the anti-HIV-1 activity of DS-4152 alone and in combination with dideoxynucleosides. METHODS: Activity of DS-4152 against HIV-1 replication was examined in MT-4, Molt-4, and peripheral blood lymphocyte cells. The inhibitory effect of the compound on syncytium-formation was determined by cocultivation of Molt-4 cells with Molt-4/IIIB cells. Inhibition of virus adsorption to the host cells was measured by a p24 antigen capture enzyme-linked immunosorbent assay. RESULTS: DS-4152 showed potent and selective inhibition of HIV-1 replication in the cell systems. Its 50% effective concentration for HIV-1 (IIIB strain) in MT-4 cells was 0.7 microgram/ml. The compound was not cytotoxic at concentrations < or = 100 micrograms/ml. DS-4125 proved inhibitory to syncytium-formation and virus adsorption. The anti-HIV-1 activities of zidovudine, dideoxycytidine and dideoxyinosine were not affected by the presence of DS-4152. CONCLUSION: DS-4152 has the potential, from these in vitro studies, to function as an anti-HIV-1 as well as an anti-angiogenesis agent. In order to determine this possibility, consequences of DS-4152 infusion on HIV-1 p24 serum levels and CD4+ cell counts over time are being examined in ongoing clinical trials in the United States on patients with AIDS-associated KS.

Antiviral Agents↗
PubMed1992

The content of urokinase-type plasminogen activator antigen as a prognostic factor in urinary bladder cancer.

Urokinase-type plasminogen activator (u-PA) is thought to be implicated in cancer invasion and metastasis. The aim of this study was to determine whether the u-PA content of cancer tissue is a prognostic factor in bladder cancer. Tissue samples from 46 patients with bladder cancer were assessed for u-PA antigen by a highly sensitive enzyme immunoassay. The relationships between the u-PA level in extracts of bladder cancer and the survival rates of the bladder-cancer patients were examined. Patients with a high u-PA level (8 ng/mg of protein and more) showed a statistically significantly higher rate of survival than those with a low u-PA level (p less than 0.005). The u-PA antigen level in cancer tissue was significantly lower in low-graded and non-invasive cancers than in others (p less than 0.01).

Aged↗
PubMed1992

Inhibition of development of Kaposi's sarcoma-related lesions by a bacterial cell wall complex.

In vitro and in vivo model systems for the study of human immunodeficiency virus (HIV)-associated Kaposi's sarcoma (KS) were used to evaluate compounds for their potential as therapeutic agents. A sulfated polysaccharide-peptidoglycan compound (SP-PG) produced by bacteria controlled the in vitro growth of acquired immunodeficiency syndrome (AIDS)-associated, KS-derived spindle-shaped cells (AIDS-KS cells) at noncytotoxic concentrations. Angiogenesis induced by AIDS-KS cells in the chicken chorioallantoic membrane assay was blocked by SP-PG, which also inhibited the vascular hyperpermeability response and the angiogenesis associated with the induction of KS-like lesions that develop after subcutaneous inoculation of AIDS-KS cells into nude mice. Suramin, pentosan polysulfate, and interferon alpha, which are currently in use for therapy of KS, were either less effective than SP-PG or much more cytotoxic, or both.

Acquired Immunodeficiency Syndrome↗
PubMed1992

The relationship between cardiovascular complications of estrogen therapy and fibrinolysis in patients with prostatic cancer.

To determine the relationship between cardiovascular complications of estrogen therapy and fibrinolysis, fibrinolysis parameters plasminogen, urokinase-type plasminogen activator (u-PA), tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor-1 (PAI-1), were assessed in 12 prostatic cancer patients before and 6 weeks after the onset of estrogen therapy. The levels of plasminogen, u-PA, and PAI-1 in the patients treated with the estrogen therapy were significantly higher than those in the patients before the therapy. The t-PA level in the patients during the therapy was significantly lower than that before the treatment. Cardiovascular complications were found in two patients (16.7%) during estrogen therapy. In the two patients, marked elevation of PAI-1 and decreased level of t-PA were observed during the therapy. These results indicate that cardiovascular complications of estrogen therapy in patients with prostatic cancer may be related to hypofibrinolysis resulting from changes of PAI-1 and t-PA.

Aged↗
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

Significant antitumor effect of a synthetic lipid A analogue, DT-5461, on murine syngeneic tumor models.

The antitumor effect of a synthetic lipid A analogue, DT-5461, was investigated using syngeneic tumor models in mice. Intravenous injection of DT-5461 into mice transplanted with solid tumors of MethA fibrosarcoma, MH134 hepatoma, MM46 mammary carcinoma, Lewis lung carcinoma (3LL), and colon adenocarcinomas 26 and 38 resulted in significant reductions in the weight of all tumors except Colon 26, with marked hemorrhagic necrosis of tumor tissues. Efficacy was almost equal to that of an Escherichia coli-type synthetic lipid A (compound 506), and also to those of some chemotherapeutics including Adriamycin, mitomycin C, fluorouracil and cisplatin. Furthermore, DT-5461 was more effective than other immunotherapeutics, including picibanil (OK-432) and lentinan. However, its antitumor effects were inferior to those of Adriamycin or OK-432 against the malignant ascites caused by intraperitoneal inoculation with MethA or with MH134 cells; life span was not prolonged by either intraperitoneal or intravenous administration. In addition, although DT-5461 showed direct inhibitory effects on the in vitro growth of MethA or MH134, these were much weaker than those of Adriamycin. These findings clearly indicated that DT-5461 with systemic administration is a highly effective antitumor agent on solid tumors, and suggest that the antitumor effect of DT-5461 with potent necrotizing activity might derive from indirect mechanisms related to the activation of host immune systems and not to the weak direct cytotoxicity.

Animals↗
PubMed1992

The prognostic significance of vascular invasion in upper urinary tract transitional cell carcinoma.

The prognostic significance of vascular invasion was evaluated in a retrospective series of 30 patients with upper urinary tract cancer who underwent a potentially curative operation. Vascular invasion was found in 11 patients (36.7%). The incidence of vascular invasion was well correlated with tumor grade and stage. The incidence of metastases postoperatively was significantly higher in the patients with (72.7%) than without (21.1%) vascular invasion (p < 0.01). The survival rate of the patients with vascular invasion was significantly lower than in those without vascular invasion (p < 0.005). In multivariate Cox regression analysis the prognostic value of vascular invasion was independent of tumor stage and grade. These results indicate that vascular invasion should predict a more unfavorable outcome in patients with upper urinary tract cancer as an independent morphological indicator.

Adult↗
PubMed1992

Bladder function in elderly men with subclinical brain magnetic resonance imaging lesions.

Among 43 men more than 60 years old who complained of urinary irritative symptoms 40 had subclinical lesions in the brain on magnetic resonance imaging (MRI). Of these 40 patients 23 (57.5%) had detrusor hyperreflexia. The mean age of the patients with and without detrusor hyperreflexia was 75.8 and 68.2 years, respectively, which is a statistically significant difference. Patients with detrusor hyperreflexia were more likely to have lesions of the basal ganglia than patients without detrusor hyperreflexia. This study suggests that detrusor hyperreflexia, subclinical MRI lesions in the brain and aging are intimately interrelated.

Aged↗
PubMed1992

Antimicrobial activity of DU-6859, a new potent fluoroquinolone, against clinical isolates.

DU-6859, (-)-7-[(7S)-amino-5-azaspiro(2,4)heptan-5-yl]-8-chloro-6- fluoro-1-[(1R,2R)-cis-2-fluoro-1-cyclopropyl]-1,4-dihydro-4-oxoquinol one-3- carboxylic acid, is a new fluoroquinolone with antibacterial activity which is significantly better than those of currently available quinolones. The MICs for 90% of methicillin-susceptible and -resistant Staphylococcus aureus and Staphylococcus epidermidis clinical isolates (MIC90s) were 0.1, 3.13, 0.1, and 0.39 microgram/ml, respectively. MIC50s of DU-6859 against quinolone-resistant, methicillin-resistant S. aureus were 8-, 32-, 64-, and 128-fold lower than those of tosufloxacin and sparfloxacin, ofloxacin and fleroxacin, ciprofloxacin, and lomefloxacin, respectively. DU-6859 inhibited the growth of all strains of Streptococcus pneumoniae and Streptococcus pyogenes at 0.1 and 0.2 microgram/ml, respectively, and was more active against enterococci than the other quinolones tested. Although the activity of DU-6859 against Pseudomonas aeruginosa was roughly comparable to that of ciprofloxacin at the MIC50 level, it was fourfold more active than ciprofloxacin at the MIC90 level. DU-6859 was also more active against other glucose-nonfermenting bacteria, Haemophilus influenzae, Moraxella catarrhalis, and Neisseria gonorrhoeae, than the other drugs tested. Strains of Bacteroides fragilis and Peptostreptococcus spp. were susceptible to DU-6859; MIC90s were 0.39 and 0.2 microgram/ml, respectively. DU-6859 generally showed activities twofold or greater than those of ciprofloxacin and the other drugs against almost all members of the family Enterobacteriaceae. The action of DU-6859 against the clinical isolates was bactericidal at concentrations near the MICs. DU-6859 activity was not affected by different media, pH, inoculum size, or human serum but was decreased in human urine.

Anti-Infective Agents↗
PubMed1992

Synergistic effect of romurtide with ampicillin against pneumococcal pneumonia in mice.

The anti-infective activity of romurtide, a synthetic muramyl dipeptide (MDP) derivative, was evaluated in experimental pneumococcal pneumonia in mice deficient in the third component of complement (C3). The compound was found to be effective against the pneumonia in combination with subcutaneous ampicillin (ABPC). This synergistic effect of romurtide with ABPC was most pronounced when the compound was administered subcutaneously 1 day before infection. Romurtide alone, however, was not effective, irrespective of its treatment timing. Similarly, consecutive treatment with ABPC alone failed to kill pneumococci in the lungs completely, and resultant regrowth of the organisms provoked purulent pneumonia. In contrast, the combination treatment of romurtide with ABPC successfully prevented most of the mice from the purulent pneumonia: the initial infiltration of resident alveolar macrophages and subsequent accumulation of macrophages were observed in the pneumonic foci. In accordance with the occurrence of these cellular responses in the lungs, pneumococci were successfully eliminated from the lungs in mice treated with romurtide in combination with ABPC. Thus, romurtide was suggested to promote recovery of the mice with pneumococcal pneumonia by activating resident and accumulated macrophages in the pneumonic foci to eliminate pneumococci from the lung.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1992

Effect of probenecid on the pharmacokinetics of DQ-2556, a new 3-quaternary ammonium cephalosporin antibiotic, in humans.

A total of 5 healthy volunteers were enrolled in a crossover study on the dose dependency and the effect of probenecid on pharmacokinetics of DQ-2556. They were administered intravenously 0.5 and 1.0 g of DQ-2556, and 1.0 g of DQ-2556 with oral administration of probenecid. The linearity in pharmacokinetics of DQ-2556 was confirmed up to the dose of 1.0 g. In the case of 1.0 g of DQ-2556 with probenecid treatment, the area under the serum concentration-time curve was larger, and total and renal clearances were less than those in the case of 1.0 g of DQ-2556 alone (by approximately 15% for each parameter, p < 0.01). These results demonstrated that DQ-2556 is secreted in the renal tubule, although it is excreted mainly by the glomerular filtration.

Administration, Oral↗
PubMed1992

Intravesical therapy with adriamycin plus verapamil in patients with superficial bladder cancer: a pilot study.

Nineteen patients with histologically proven superficial bladder cancer (Ta, T1) were treated with intravesical instillation of 30 mg of adriamycin (ADM) dissolved in 24 ml physiological saline plus 15 mg of verapamil (VR) (6 ml) every day for 10 days. In spite of the short period of treatment, 6 of the 18 evaluable patients (33.3%) showed complete response (CR) and a further 5 (27.8%) showed partial response (PR). Five of the 6 patients with CR were recurrent cases who had previously received prophylactic intravesical instillation chemotherapy including ADM. Irritative urinary symptoms were observed in 11 of the 19 patients (57.9%). However, these symptoms were mild in the majority of patients and the treatment was completed without interruption in all but 1 patient. There was no significant absorption of ADM and VR into the systemic circulation. No clinical evidence of systemic toxicity was observed. These results suggest that combination of ADM and VR has a possibility to be a useful prophylactic intravesical instillation chemotherapy after endoscopic resection of not only primary but also recurrent chemoresistant bladder cancers.

Administration, Intravesical↗