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K Oishi

Publications and source records attributed to K Oishi.

At least 127 records · Page 7Linked to original sources
PubMed1997

Cloning of cDNA for vitellogenin of the parasitoid wasp, Pimpla nipponica (Hymenoptera: Apocrita: Ichneumonidae): vitellogenin primary structure and evolutionary considerations.

The cDNA for vitellogenin (Vg) of the parasitoid wasp Pimpla nipponica (Hymenoptera: Apocrita) was cloned and sequenced. The deduced amino acid sequence with 1807 residues was obtained. The N-terminal 20 amino acids chemically determined for vitellin (Vn) agreed completely with the deduced 20 amino acids that follow the 16 amino acid residues for putative signal peptide. The cDNA clone for the Vg of the turnip sawfly Athalia rosae (Hymenoptera: Symphyta), previously obtained and partially sequenced, was also completely sequenced and the amino acid sequence deduced. Amino acid sequences were compared between these two species and also with known Vg sequences from other insects. Common to all these insects is the presence of two long regions with relatively well-conserved amino acid sequences, one near the N-terminal extending 267-282 residues (including two cysteines at conserved locations), and the other starting at position 450 to 655 and extending 279-283 residues, and of a region at the C-terminal extending some 200 residues (about 250 in Aedes aegypti due to the presence of a serine-rich stretch) with 10 cysteines at conserved locations. A molecular phylogenetic tree was constructed.

Amino Acid Sequence↗
PubMed1997

Inhibition of neutrophil apoptosis by antioxidants in culture medium.

Neutrophil apoptosis is an important mechanism that has implications for understanding the life span and toxic potentials of neutrophils at inflamed sights. In this study the authors examined the possibility that reactive oxygen species (ROS) released by neutrophils can regulate neutrophil survival. Cu,Zn-superoxide dismutase (Cu,Zn-SOD), Mn-SOD, and catalase in culture media were significantly effective in delaying the spontaneous apoptosis, suggesting that ROS play an important role in the resolution of inflammation by inducing neutrophil apoptosis. In this experiment, boiled Cu,Zn-SOD had no effect on inhibiting the apoptosis, but boiled Mn-SOD from Bacillus stearothermophilus was more effective in inhibiting the apoptosis than untreated Mn-SOD at the same dose. However, the boiled Mn-SOD showed only 80% of O2- inhibitable activity compared with the untreated Mn-SOD. This effect may be attributed to the partial liberation of manganese because MnCl2 inhibited the apoptosis effectively. Furthermore, Cu,Zn-SOD was effective in delaying apoptosis only when added to the culture within the first 3 h of incubation, suggesting that the isolation of neutrophils from peripheral blood enhances apoptosis of neutrophils.

Antioxidants↗
PubMed1997

Endogenous tumor necrosis factor (TNF) alpha mediates neutrophil accumulation at the mid-phase of a murine model of Pseudomonas aeruginosa pneumonia.

To determine the role of endogenous tumor necrosis factor (TNF) alpha on neutrophil influx into the lungs in acute Pseudomonas aeruginosa pneumonia, we evaluated TNF alpha activity, inflammatory cell response and neutrophil chemotactic activity in the bronchoalveolar lavage fluids (BALFs) of P. aeruginosa-infected mice. In the case of fatal pneumonia, the TNF alpha activity in the BALFs appeared within 3 hr, peaked at 6-12 hr and attenuated within 24 hr after intratracheal challenging, while no TNF alpha activity was detected in the plasma. The elevation of TNF alpha activity in the BALFs was closely associated with neutrophil accumulation. Mirroring the TNF alpha activity response and the influx of neutrophils into the murine airway, the number of neutrophils in the BALFs increased within 3 hr, peaked at 6-12 hr and remained elevated up to 24 hr after challenging. Neutralization of the TNF alpha activity in the BALFs with anti-murine TNF antiserum decreased the level of neutrophil migration by BALF 45.0-49.7% at 6 hr and 49.3-54.2% at 12 hr, while the neutralizing antiserum had no effect on the level of neutrophil migration by BALFs at 3 and 24 hr. Furthermore, the intravenous administration of anti-murine TNF antiserum 2 hr before challenging significantly inhibited neutrophil migration into the lungs of mice with sublethal pneumonia (P < 0.05; compared with mice receiving pre-immune serum). These data suggest that intra-alveolar TNF alpha plays an important role in causing lung neutrophil accumulation at the mid-phase of murine P. aeruginosa pneumonia.

Animals↗
PubMed1997

Quality of life survey of urinary diversion patients: comparison of continent urinary diversion versus ileal conduit.

BACKGROUND: Continent urinary reservoirs (CUR) have become one of the major options for patients requiring urinary diversion to improve their quality of life (QOL). To assess whether CUR enhanced postoperative QOL, we surveyed patients with CUR and ileal conduit (IC) using a questionnaire sent by mail. PATIENTS AND METHODS: The questionnaire consisted of 133 questions that covered physical and mental status, social life, sexual habits and symptoms related to urinary diversions. A total of 172 questionnaires were sent out, and 137 (80%) patients (74 CUR and 63 IC patients) responded. RESULTS: Basic physical conditions were similar in the 2 groups, except for sleeping habits. Regarding social life, however, the CUR group showed better scores in bathing habits and frequency of overnight travel. Parastomal dermatitis was more frequent in the IC group and the patients were more hesitant to show their stoma to others. On the other hand, about half of the patients in the CUR group complained of troublesomeness in self-catheterization, especially at night. Overall, 74% and 41% of the patients in the CUR and IC group were satisfied with their urinary diversion. When the Kock pouch and Indiana pouch were compared, no statistically significant differences were found in average capacity, maximum capacity, or frequency of self-catheterization. CONCLUSIONS: CUR recipients have enhanced QOL regarding the stoma, travel and sleeping habits as compared to ileal conduit. However, troublesomeness of night time self-catheterization was noted in the CUR group. Individualized selection of the type of urinary diversion with informed consent is essential.

Aged↗
PubMed1997

Nitric oxide and aneurysm formation in Kawasaki disease.

The objective of this study is to show that nitric oxide plays a role in the development of coronary artery abnormalities in Kawasaki disease. We examined nitrite+nitrate, biopterin and neopterin in 316 urine samples of 34 patients with Kawasaki disease, those of 24 patients with other diseases, and those of 25 healthy children acting as a control group, because urinary nitrite + nitrate are reportedly useful as markers of nitric oxide generation in vivo, and pathways for neopterin-biopterin synthesis and nitric oxide generation are tightly coupled. In our study, the children with Kawasaki disease excreted more urinary nitrite + nitrate and neopterin than did the healthy control group children and excreted abnormally high quantities more often than did the patients with other diseases. Good relationships were found between the urinary nitrite + nitrate levels and the urinary biopterin levels, and between these biopterin levels and the urinary neopterin levels. Nitric oxide is therefore thought to be generated in abnormally high quantities, and to be closely related to the pathology of Kawasaki disease and to the development of coronary artery abnormalities. The role of nitric oxide in Kawasaki disease should be further studied to elucidate the pathophysiology of the disease and to aid in the development of new treatments.

Biomarkers↗
PubMed1997

Nitrite reductase from Pseudomonas aeruginosa induces inflammatory cytokines in cultured respiratory cells.

Persistent infection with Pseudomonas aeruginosa increases interleukin-8 (IL-8) levels and causes dense neutrophil infiltrations in the airway of patients with chronic airway diseases. To investigate the role of P. aeruginosa infection in IL-8 production in the airway of these patients, we examined whether cell lysates of P. aeruginosa could cause IL-8 production from human bronchial epithelial cells. Diluted sonicated supernatants of P. aeruginosa (SSPA) with a mucoid or nonmucoid phenotype stimulated human bronchial epithelial (BET-1A) cells to produce IL-8. In this study, we have purified a 59-kDa heat-stable protein with IL-8-inducing activity from the SSPA by sequential ion-exchange chromatography. The N-terminal sequence of this purified protein completely matched a sequence at the N-terminal part of the mature protein of nitrite reductase from P. aeruginosa. In addition, immunoblotting with a polyclonal immunoglobulin G (IgG) against recombinant Pseudomonas nitrite reductase demonstrated a specific binding to the purified protein. Furthermore, the immunoprecipitates of the SSPA with a polyclonal IgG against recombinant nitrite reductase induced a twofold-higher IL-8 production in the BET-1A cell culture than did the immunoprecipitates of the SSPA with a control IgG. These lines of evidence confirmed that Pseudomonas nitrite reductase was responsible for IL-8 production in the BET-1A cells. The purified nitrite reductase induced maximal expression of IL-8 mRNA in the BET-1A cells at 1 to 3 h after stimulation, and the IL-8 mRNA expression declined by 8 h after stimulation. New protein translation was not required for nitrite reductase-mediated IL-8 mRNA expression in the BET-1A cells. Nitrite reductase stimulated the BET-1A cells, as well as human alveolar macrophages, pulmonary fibroblasts, and neutrophils, to produce IL-8. In contrast, nitrite reductase induced significant levels of tumor necrosis factor alpha and IL-1beta protein only in human alveolar macrophages. These data support the notion that nitrite reductase from P. aeruginosa induces the production of inflammatory cytokines by respiratory cells and may contribute to the pathogenesis of chronic airway diseases and persistent P. aeruginosa infection.

Bronchi↗
PubMed1996

Cloning and characterization of hsc1+, a heat shock cognate gene of the fission yeast Schizosaccharomyces pombe.

A heat shock cognate gene from the fission yeast Schizosaccharomyces pombe (Sp), designated hsc1+, was cloned. The putative translation product of hsc1+ contains 613 aa, with an estimated molecular mass of 67,205 Da, and is more similar to the Saccharomyces cerevisiae (Sc) heat shock cognate protein SSB1 (69% identity) than the Sp heat-inducible ssp1+ gene product (41% identity). The hsc1+ mRNA was abundant during steady-state growth at 23 degrees C and decreased upon heat shock. Immunoblot analysis showed that the hsc1 protein is also abundant and constitutively expressed, however, we could not observe significant change in the protein level upon heat shock. DNA blot analyses indicated that hsc1+ is localized in Sp chromosome II, and suggested that the Sp genome contains a relatively smaller number of HSP70 genes compared with the Sc genome.

Amino Acid Sequence↗
PubMed1996

Airway interleukin-8 in elderly patients with bacterial lower respiratory tract infections.

We investigated the interleukin-8 (IL-8) levels and neutrophil numbers in the sputum of 9 elderly patients with lower respiratory tract infections, including Pseudomonas aeruginosa infection, before and after treatment with various antimicrobial agents. The IL-8 levels in sputum supernatants and the neutrophil numbers in sputum smears from 9 patients decreased significantly after the elimination of the causative respiratory pathogens. We also demonstrated that human recombinant IL-8 at a range of 6.25-25 ng/ml significantly enhanced opsonophagocytic killing of P. aeruginosa immunotype-1 strain by human neutrophils in the presence of a serotype-specific anti-lipopolysaccharide monoclonal antibody and fresh normal human serum. These data suggest that the level of IL-8 production in the airways of patients with lower respiratory tract infections is dependent on bacterial densities, and indicate the important role of IL-8 not only in neutrophil migration but also in opsonophagocytic killing of bacteria in the lower respiratory tract.

Aged↗
PubMed1996

A monoclonal antibody reactive with a common epitope of Moraxella (Branhamella) catarrhalis lipopolysaccharides.

A hybrid cell line producing a monoclonal antibody (MAb) against Moraxella (Branhamella) catarrhalis lipopolysaccharide (LPS) was established. The specificity of the MAb 1B12 to purified rough LPSs from six strains of M. catarrhalis was ascertained by enzyme-linked immunosorbent assay (ELISA), competitive-inhibition ELISA, and immunoblotting. MAb 1B12 bound to live bacterial cells and culture supernatants from a total of 34 strains of M. catarrhalis, including 12 strains with different LPS serotypes. No cross-reactions with smooth and rough LPSs from selected enterobacterial and nonenterobacterial strains, with other respiratory pathogens, or with Neisseria species were observed. These data suggest that MAb 1B12 recognizes a common epitope of M. catarrhalis LPS which differs from serotype determinants.

Antibodies, Monoclonal↗
PubMed1996

Valve detachment after aortic valve replacement--a successfully reoperated case with the Cabrol technique.

A 50-year-old Japanese male was admitted with a 1 month history of progressive shortness of breath, palpitations, and intermittent low-grade fever. On admission, a musical diastolic murmur (sea-gull murmur) was heard on the 3rd left sternal border. Blood studies showed an accelerated erythrocyte sedimentation rate, and positive C-reactive protein. Retrograde aortography revealed severe aortic regurgitation. At the operation, the aortic wall was remarkably thickened, and the aortic valve commissures between the right and left coronary cusps and between the left and non-coronary cusps had completely detached from the aortic wall. The aortic valve was replaced with a St Jude Medical valve using pledgeted sutures. Histologic studies of the aorta and aortic valve revealed no evidence of any pathologic changes. Echocardiography performed 82 days after aortic valve replacement showed severe paravalvular leakage and valve detachment. At the reoperation, the prosthetic valve was detached from the extremely edematous and fragile native aortic annulus. There was no vegetation or abscess formation. Aortic root replacement with the Cabrol technique was performed using a composite graft in which the prosthetic valve was placed 1 cm above the proximal extremity to reduce the tension on the suture line and the aortic annulus. Histologic study of the aorta after the reoperation showed non-specific inflammatory disease. The patient, who received steroid therapy, has recovered without any signs of graft detachment or pseudoaneurysm formation.

Aortic Valve↗
PubMed1996

An application of nitrogen microwave-induced plasma mass spectrometry to isotope dilution analysis of selenium in marine organisms.

Nitrogen microwave-induced plasma mass spectrometry was studied for its applicability to the isotope dilution analysis of selenium in biological samples. Spectroscopic interference by calcium, which is present in high concentrations in biological samples, was investigated. No detectable background spectrum was observed for the major selenium isotopes of 78Se and 80Se. No detectable interferences by sodium, potassium, calcium and phosphorus on the isotope ratio 80Se/78Se were observed up to concentration of 200 mg/ml. The method was applied to the analysis of selenium in biological reference materials of marine organisms. The results showed good agreement between the certified and found values.

Animals↗
PubMed1996

Loss of tumor necrosis factor production by human monocytes in falciparum malaria after their maturation in vitro.

In Plasmodium-infected mammals, phagocytosis and production of tumor necrosis factor (TNF) by monocytes and macrophages are prominent features. The present work aimed at clarifying the relationship between the maturation of human monocytes to macrophages and their TNF productivity and phagocytic ability in the presence of Plasmodium falciparum-infected erythrocytes. Fresh monocytes produced a significantly higher quantity of TNF in the presence of schizont-infected erythrocytes than macrophages obtained by in vitro monocyte maturation on autologous serum, whereas phagocytic activity of macrophages was much higher than that of fresh monocytes. This indicated that the TNF-inducing factors from P. falciparum-infected erythrocytes could stimulate fresh monocytes, but not macrophages, to release TNF, regardless of their development of phagocytosis. Activation of macrophages by interferon-gamma could not recover their TNF productivity in the presence of P. falciparum-infected erythrocytes, but it enhanced their TNF productivity in the presence of lipopolysaccharide(s). The TNF-inducing factors were contained mainly in erythrocytes infected with mature schizonts but not in erythrocytes infected with the younger stages of the parasites. Fractionation of infected erythrocytes revealed that both soluble and insoluble components almost equally contained those factors.

Animals↗
PubMed1996

Effect of long-term administration of finasteride (MK-906), an inhibitor of 5 alpha-reductase, in patients with benign prostatic hyperplasia.

We evaluated the effect of long-term administration of finasteride (MK-906), a potent inhibitor of 5 alpha-reductase in patients with benign prostatic hyperplasia (BPH). The effect of an increase in dose was also assessed. Finasteride was administered to 61 patients with BPH at the dose of 1 mg/day for 48 weeks. Thirty three of these patients subsequently received finasteride at the dose of 5 mg/day for further 24 weeks in an open extension study. Urinary symptoms, urinary flow rate, residual urinary volume, prostatic volume and serum concentrations of dihydrotestosterone and prostate-specific antigen were examined periodically during the treatment. The size of the prostate and total urinary symptom scores decreased progressively during the first 16 weeks of treatment. The patients who received finasteride had a significant increase in the maximal urinary flow rate and a significant decrease in residual urinary volume. After 72 weeks of treatment, finasteride at an increased dose of 5 mg did not provide additional benefit to patients, although the effects of the drug at a dose of 1 mg were well maintained. Treatment with finasteride was well tolerated at both doses. In conclusion, the treatment of BPH with 1 mg of finasteride per day for 48 weeks results in a significant increase in maximal urinary flow rate, and a decrease in prostatic volume, symptoms of obstruction and residual urinary volume, with minimal toxicity.

5-alpha Reductase Inhibitors↗
PubMed1996

[Phase I study of bicalutamide (Casodex), a nonsteroidal antiandrogen in patients with prostatic cancer].

A phase I study (open trial) of bicalutamide (Casodex), a non-steroidal antiandrogen, was conducted on 16 patients with prostatic cancer (stage C to D). The patients were given 10, 30, 50, 80 or 100 mg of bicalutamide orally daily for 12 weeks. Adverse reactions were observed in 8 out of 16 patients, but almost all were mild. Breast pain, gynecomastia and hot flushes were observed in 6 patients. Adverse reactions regarding liver function tests were observed in 3 patients. These were increased glutamic-oxalacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), alkaliphosphatase (AL-P) or gamma guanosine 5'-triphosphate (gamma-GTP). However, during or after the treatment period the elevated values were reversed to the pretreatment level. In terms of efficacy, anti-tumor effect was observed in 1 or 2 patients at each dose. Serum concentrations of luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and estradiol increased during treatment. Plasma concentrations of the R (-) enantiomer, which has antiandrogenic activity, reached the steady state 6-8 weeks after the initiation of treatment; its apparent plasma elimination half-life observed following repeated administration was 8.4 +/- 1.1 days. In conclusion, bicalutamide (10-100 mg od) is considered to be tolerated well enough to be administered to patients with prostatic cancer and has shown evidence of anti-tumor effect.

Administration, Oral↗
PubMed1996

[Clinical early phase II study of bicalutamide (Casodex) in patients with prostatic cancer].

To investigate the efficacy and safety of bicalutamide (Casodex) with its clinically recommended dose, the randomized early phase II study was performed in 124 patients with prostatic cancer (stage C, D). The patients were given 50, 80 or 100 mg of bicalutamide orally once a day in fixed doses for 12 weeks; 122 patients were eligible for evaluation. The overall response rate was 50.0% (20/40), 61.0% (25/41) and 53.7% (22/41) in the 50 mg, 80 mg and 100 mg groups, respectively. The response rate in prostate lesion, bone and lymph node metastases was slightly higher in the 80 mg group than in the 50 mg and 100 mg groups. The proportion of patients showing a response with regard to serum PSA (CR and PR) was 84.2, 92.7 and 97.6% in the 50, 80 and 100 mg groups, respectively. The incidence of adverse reactions was 65.0, 61.0 and 61.0% in the 50, 80 and 100 mg groups, respectively, and there was no significant difference in overall safety rating in the three groups. Frequent adverse reactions were gynecomastia and breast pain. Only one patient in the 80 mg group was withdrawn due to shortness of breath. Serum concentrations of LH, testosterone and estradiol increased significantly after treatment. Bicalutamide was concluded to be effective and well tolerated in patients with prostatic cancer, and its recommended dose was 80 mg once daily.

Administration, Oral↗
PubMed1995

Effect of nuclear Ca2+ uptake inhibitors on Ca(2+)-activated DNA fragmentation in rat liver nuclei.

The effect of nuclear Ca2+ uptake inhibitors on the Ca(2+)-activated DNA fragmentation in rat liver nuclei was investigated. The addition of Ca2+ (40 microM) into the reaction mixture containing liver nuclei in the presence of 2.0 mM ATP caused a remarkable increase in nuclear DNA fragmentation. This Ca(2+)-activated DNA fragmentation was not seen in the absence of ATP, because nuclear Ca2+ uptake is not initiated without ATP addition. Moreover, the presence of various reagents (10 microM arachidonic acid, 2.0 mM NAD+, 10 microM zinc sulfate and 0.2 mM N-ethylmaleimide), which could inhibit Ca(2+)-ATPase activity and Ca2+ uptake in the nuclei, produced a significant inhibition of the Ca(2+)-activated DNA fragmentation in the nuclei. The results show that the Ca(2+)-activated DNA fragmentation is involved in the uptake of Ca2+ by the nuclei, suggesting a role of Ca2+ transport system in the regulation of liver nuclear functions.

Animals↗
PubMed1995

17 beta-Estradiol stimulates the expression of hepatic calcium-binding protein regucalcin mRNA in rats.

The effect of nuclear receptor-related hormones on the expression of hepatic calcium-binding protein regucalcin mRNA in rats was investigated. The change of regucalcin mRNA levels was analyzed by Northern blotting using liver regucalcin cDNA (0.9 kb of open-reading frame). A single subcutaneons administration of 17 beta-estradiol (0.5, 1.0 and 2.0 mg/kg body weight) in rats induced a remarkable increase of regucalcin mRNA in liver; the level was about 200% of control at 24 h after the administration of 2.0 mg/kg. The increase showed about 350% even at 6 h after the administration. Meanwhile, hepatic regucalcin mRNA level was not appreciably altered by a single subcutaneous administration of thyroxine (T4) (20, 40 and 80 mg/kg) or hydrocortisone (10 and 30 mg/kg) in rats. The present study demonstrates that the expression of hepatic regucalcin mRNA is stimulated by estrogen action in the liver nuclei of rats.

Animals↗