Biomedical subjects

Y Sakata

Publications and source records attributed to Y Sakata.

At least 235 records · Page 13Linked to original sources

PubMed1994

[Clinical studies of arbekacin sulfate in the pediatric field].

UNLABELLED: A clinical investigation was carried out to evaluate arbekacin, an aminoglycoside, in the treatment of MRSA infections (pneumonia, septicemia, etc.) of pediatric patients. The obtained results are summarized as follows. 1. CLINICAL RESULTS: Excluding those patients who met the present exclusion criteria and withdrawal cases from a total of 18 patients, 10 patients (3, 6, and 1 cases of septicemia, pneumonia, and urinary tract infection, respectively) were subjected to clinical evaluation. These were composed of 1, 1, 6, and 2 cases of neonate, infants, pre- and school age children, respectively. Excellent, good and fair results were obtained in 5, 2, and 3 patients, respectively; thus, the efficacy rate was 70.0%. The efficacy rate by disease was 100%, 50.0% and 100% in septicemia, pneumonia, and urinary tract infection, respectively. The bacteriological eradication were obtained in 70.0% of the total patients; by disease, these rates were 100% and 50.0% in septicemia/urinary tract infection and in pneumonia, respectively. The MIC50 as well as the MIC80 against MRSA strains isolated from 9 patients were 0.39 microgram/ml and 1.56 micrograms/ml, respectively. No adverse reactions were observed in the 15 patients, while in laboratory test values, one case each out of 12 patients examined showed gamma-GTP elevation, proteinuria, and hematuria. 2. Pharmacokinetics: The pharmacokinetics of the agent was investigated in a total of 9 patients, which included 1 neonate and 4 cases each of pre- and school age children. The Cmax, 4.85-8.83 micrograms/ml, was observed immediately after the termination of the instillation. The T1/2's were 4.96 hours, 1.24-2.54 hours, and 1.78-1.88 hours in the neonate, the pre- and the school age children, respectively; in the neonate the half-life was longer. When 1.92-2.7 mg/kg were administered to 3 each of the pre- and school age children, urinary excretion rates in the first 6-8 hours were 40.1-56.5% of the dosages administered. In all cases, the urinary concentrations were highest in the first 2 hours, after the administration, and then gradually decreased. These results suggest that arbekacin is a useful antibiotic for treating MRSA infections in the pediatric field.

Adolescent↗

PubMed1994

[Intractable bacterial infections in the nervous system].

It is not exaggeration to say that infectious meningitis is most often seen among infections of the nervous system caused by various microorganisms, in which viruses are main causative pathogens. Infectious meningitis due to bacteria includes purulent one with acute progress, tuberculous and fungal ones which are representative for subacute meningitis. They can not be easily treated. As brain abscess is similar to them, diagnosis and chemotherapy on these four diseases are briefly summarized here. It is needless to say that the prognosis is influenced by early diagnosis and how fast appropriate chemotherapy is started in all four diseases. Dexamethasone therapy should be tried in purulent meningitis in order to decrease hearing disturbance which is unable to be prevented by chemotherapy.

Anti-Bacterial Agents↗

PubMed1994

[AML1 gene rearrangements, but no 8;21 translocation in a child with acute myeloblastic leukemia (M2)].

A 3-year-old girl developed fever and bilateral exophthalmos. Her initial peripheral blood counts on admission were; Hb8.7 g/dl, Plt. 10.6 x 10(4)/microliters, and WBC 30,890/microliters with 31% peroxidase-positive blasts, some of which contained Auer rods. The bone marrow smears showed 22% blasts with a certain degree of maturation. She was diagnosed as having M2 type AML. Computed tomography revealed bilateral retoro-orbital tumor. The bone marrow karyotype showed no 8;21 translocation but a loss of one sex chromosome. Molecular analysis of the bone marrow cells disclosed rearrangements of the AML1 gene. Chimeric mRNA coded by the AML1-MTG8 gene was also detected by the RT-PCR method. We concluded that this patient had a masked 8;21 translocation in her leukemic cells.

Child, Preschool↗

PubMed1994

[A case of malignant fibrous histiocytoma of the pulmonary artery].

We presented a rare case of primary pulmonary artery sarcoma. A 27-year-old female was admitted with fever and back pain. Her chest X-ray showed right pleural effusion and infiltrate in the right lower lobe. Enhanced chest CT scan and pulmonary angiogram showed an intraluminal filling defect of the pulmonary trunk. She was operated on under cardiopulmonary bypass. Following the incision of the pulmonary trunk, a polypoid soft yellowing mass was exposed. The local tumor resection and the right pneumonectomy were performed. Histological and immunohistochemical studies of the tumor revealed malignant fibrous histiocytoma. She made a good recovery but died of distant metastases 10 months after surgery.

Adult↗

PubMed1994

[Basic and clinical studies on cefditoren pivoxil in pediatric field].

Cefditoren pivoxil (CDTR-PI, ME1207) granules, a new oral cephem, was given to pediatric patients with infectious diseases to evaluate antibacterial activities against clinical isolates, pharmacokinetics, clinical efficacy and safety, and the following results were obtained. 1. In sensitivity test, 30 strains were used comprised of 5 species, isolated from the patients before administered with CDTR-PI. Against Staphylococcus aureus, MICs of 7 agents, cefditoren (CDTR), cefaclor, cefixime, cefteram, cefotiam, cefpodoxime and methicillin, were determined. Against other 4 species, MICs of the above 6 agents excluding methicillin were determined. Among Gram-positive cocci tested, the MICs of CDTR were 0.78 to 100 micrograms/ml or higher against S. aureus (16 strains), < or = 0.025 microgram/ml against Streptococcus pyogenes (5 strains), and 0.10 or 0.39 microgram/ml against Streptococcus pneumoniae (2 strains). These values were equal to or lower than those of conventional cephems and of methicillin. Among Gram-negative rods tested, the MICs of CDTR were < or = 0.025 microgram/ml against Haemophilus influenzae (3 strains), and 0.10 or 0.20 microgram/ml against Escherichia coli (4 strains). Also, these values were equal to or lower than those of conventional cephems. 2. When CDTR-PI granules was orally administered in a single dose of 3.0 mg/kg to 1 patient and that of 6.0 mg/kg to 2 patients 30 minutes after meal, plasma CDTR concentrations reached their maxima 4 hours after administration in the former patient and 1 or 2 hours after administration in the latter 2 patients, and the peak plasma concentrations were 1.91, 3.46 and 4.82 micrograms/ml with half-lives of 1.01, 0.81 and 0.88 hours and AUCs of 8.62, 9.89 and 13.52 micrograms.hr/ml, respectively. Dose-dependency was observed for the peak plasma concentrations and AUCs also tended to depend on dose excepting for the AUC in one 6.0 mg/kg patient. 3. The urinary concentrations in the above patients reached their peaks at 4 to 6 hours after administration in one 3.0 mg/kg patient and at 4 to 6 hours and 2 to 4 hours after administration in two 6.0 mg/kg patients, and the corresponding values were 126.0, 195.0 and 234.0 micrograms/ml, respectively. Recovery rates in the first 8 hours after administration were 18.2, 24.6 and 21.3%, respectively. 4. Of 53 patients with 13 diseases, CDTR-PI was clinically judged "excellent" in 32 (60.4%) and "good" in 21 (39.6%), showing excellent efficacy. 5. Bacteriologically, excellent results were obtained, i.e., 29 (96.7%) of 30 strains from 5 species were eradicated. 6. Side effects were observed in none of the 54 patients treated.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacteria↗

PubMed1994

[Sequential methotrexate/5-fluorouracil therapy with 5'-deoxy-5-fluorouridine against advanced gastric cancer: comparison between bolus injection and drip infusion of 5-fluorouracil administration. Hirosaki Cooperative Study Group for Cancer Chemotherapy].

Forty-two patients with gastric cancer were entered in this study. Forty-one of them were eligible and administered sequential methotrexate (MTX)/5-fluorouracil (5-FU) with 5'-deoxy-5-fluorouridine (5'-DFUR). 5-FU was administered intravenously by drip infusion for 2 hours in 22 cases (group A), and was infused by bolus injection in 19 cases (group B). The treatment schedules were as follows: MTX 100 mg/m2 was given intravenously (i.v.) followed by 5-FU 600 mg/m2 i.v. 2 hours later and leucovorin 15 mg/body i.v. 8 and 20 hours later. This cycle was repeated once a week. 5'-DFUR 1,200 mg/body/day was given orally on 5 consecutive days per week. Three of 20 cases (15%) in group A showed PR, while 5 of 15 cases (33%) in group B showed PR. Median survival time was 2.8 months in group A and 3.7 months in group B. There was, however, no statistical difference. Gastrointestinal toxicity was commonly observed. Leukocytopenia was more severe in group B. Alopecia was more frequently observed in group B (p < 0.025). These results suggested bolus injection of 5-FU was a promising way of administration in sequential MTX/5-FU therapy.

Administration, Oral↗

PubMed1994

[Late phase II study of irinotecan hydrochloride (CPT-11) in advanced gastric cancer. CPT-11 Gastrointestinal Cancer Study Group].

A multi-institutional collaborative late phase II study of irinotecan hydrochloride (CPT-11) was performed on patients with advanced gastric cancer. CPT-11 was administered as a 100 mg/m2 weekly intravenous infusion or as 150 mg/m2 fortnightly. Of 81 registered patients, 77 cases were eligible and 60 cases were evaluable for response. The overall response rate for evaluable cases was 23.3% (14/60), and the response rate was 16.1% (9/45) for the patients who had received prior chemotherapy. The primary tumor showed a 4.5% response, while metastatic lesions in the lymph-nodes, lungs, and liver showed response rates of 36.4%, 33.3%, and 17.4%, respectively. The major toxicities (> or = Grade 3) were leukopenia (41.2%), anemia (28.9%), diarrhea (22.4%) and anorexia (19.7%). These toxicities were generally reversible. CPT-11 showed activity against advanced gastric cancer, suggesting that further clinical studies of CPT-11 combined with other active chemotherapy agents are warranted.

Adenocarcinoma↗

PubMed1994

[A late phase II study of CPT-11, irinotecan hydrochloride, in patients with advanced pancreatic cancer. CPT-11 Study Group on Gastrointestinal Cancer].

A late phase II study of CPT-11 was conducted to evaluate the antitumor effect and toxicity of CPT-11 in patients with advanced pancreatic cancer as a cooperative study of 19 institutions. From February 1990 to June 1992, 61 patients with advanced pancreatic cancer were enrolled in this study. Fifty-seven patients were evaluable for toxicity and 35 for response. CPT-11 was administered as a 100 mg/m2 weekly intravenous infusion (regimen A) or as a 150 mg/m2 every two weeks (regimen B). The response rate was 11.4% (4/35). The primary tumor showed a 10.3% (3/29) response and the liver metastases showed a 10.5% (2/19) response. The major toxicities were myelosuppression and gastrointestinal symptoms. The incidences (> or = Grade 2) of leukopenia, anemia, anorexia, nausea/vomiting, alopecia and diarrhea were 61.4% (35/57), 56.1% (32/57), 70.2% (40/57), 56.1% (32/57), 40.4% (23/57) and 36.8% (21/57), respectively. The incidence of diarrhea was higher with regimen A than with regimen B, but the antitumor activity was no different between the two regimens. These results suggested that CPT-11 has some antitumor activity against advanced pancreatic cancer.

Adult↗

PubMed1993

The anti-platelet actions of FR122047, a novel cyclooxygenase inhibitor.

The anti-platelet actions of 1-[(4,5-bis(4-methoxyphenyl)-2- thiazoyl)carbonyl]-4-methylpiperazine hydrochloride (FR122047) were investigated in vitro and in vivo. FR122047 was 100 times more potent than aspirin against arachidonic acid- and collagen-induced human and guinea-pig platelet aggregation in vitro. Its actions on platelets were a result of cyclooxygenase inhibition. The single oral dose of FR122047 inhibited arachidonic acid- and collagen-induced aggregation with an ED50 of 280 micrograms/kg and 530 micrograms/kg, respectively, in guinea-pigs. The anti-platelet action was augmented 5-10 times by repeated administration for 4 days. At 1 mg/kg the inhibitory actions were prolonged for 48 h and the drug concentration was < 0.1 ng/ml in platelet-poor plasma at 24 h and 0.282 ng/ml in platelet-rich plasma at 48 h. The safety margin in rats (minimum ulcerogenic dose/ED50 for anti-platelet aggregation) of FR122047 was more than 70, while that of aspirin was only 1.2. These results indicate that FR122047 is concentrated in platelets and may be a useful anti-platelet agent.

Animals↗

PubMed1993

Identification of the plasminogen activator inhibitor-1 binding heptapeptide in vitronectin.

We have shown that a heptapeptide which resides in the middle part of vitronectin (VN) is responsible for binding to plasminogen activator inhibitor-1 (PAI-1). A single PAI-1 binding peptide was isolated from human VN after limited proteolysis with protease V8. The amino acid sequence of the fragment corresponded to residues Gly-115-Glu-121 of VN. A murine monoclonal antibody (JYV-1) raised against human VN bond to the same fragment and inhibited binding of PAI-1 to VN. A synthetic peptide (V-115), comprising residues Gly-115-Glu-121 of human VN, competed with VN for both PAI-1 and JYV-1 in a dose-dependent manner. Synthetic peptide V-111 (Ser-111-Glu-121) had a stronger inhibitory effect than V-115 on binding of PAI-1 or JYV-1 to VN. V-111 also inhibited the binding of human PAI-1 to mouse and rabbit VN. The functional half-life of PAI-1 activity was prolonged approximately 2-fold in the presence of V-111 (1 mM). This stabilizing effect of V-111 was equivalent to intact VN, although a 1000-fold higher molar concentration of V-111 over VN was required. These data indicated that VN residues Gly-115-Glu-121 contain a PAI-1 binding site.

Amino Acid Sequence↗

PubMed1993

Role of bradykinin in microbial infection: enhancement of septicemia by microbial proteases and kinin.

Data presented herein will show that bradykinin, microbial proteases which activate the kinin generating cascade, and kininase inhibitors can enhance septicemia by approximately 10 to 100 fold in mice infected intraperitoneally (i.p.) with a strain of bacteria, Pseudomonas aeruginosa 621, which does not usually produce a kinin generating protease. Bacterial spreading was evaluated either in the blood or in the spleen by colony formation on agar plates. Using the P. aeruginosa kaguma strain which produces a large amount of proteases, further experiments were carried out. Results showed that two different protease inhibitors (ovomacroglobulin and a synthetic peptide inhibitor against pseudomonal elastase) as well as a kinin antagonist suppressed bacterial dissemination to 1/10-1/100 of control. Similar results were observed in experiments using Vibrio vulnificus. These data support the hypothesis that microbial proteases and especially bradykinin is responsible for facilitation of microbial dissemination in vivo.

Animals↗

PubMed1993

Ubiquitous nuclear proteins bind to 5' upstream region of major Kunitz chymotrypsin inhibitor gene in winged bean.

Winged bean Kunitz chymotrypsin inhibitor (WCI) accumulates abundantly in seeds and tuberous roots of winged bean plant. In seeds, the WCI mRNA is observed transiently during seed maturation period. The WCI is encoded by a multigene family and the major WCI (WCI-3) is encoded by two nearly identical genes (WCI-3a and WCI-3b genes), in which nucleotide sequences in the 1.1 kb 5' flanking regions are about 99% homologous to each other and the transcribed regions are completely identical. Here we report the detection of two types of nuclear proteins which bind to the multiple sites in the 5' upstream region of the WCI-3a gene. One of the proteins, band 1-forming protein, also bound to cauliflower mosaic virus 35S (CaMV35S) promoter, but another protein, band 3-forming protein, did not. DNaseI footprinting analysis showed that these proteins bound to AT-rich upstream regions in the WCI-3a gene. Addition of poly(dA-dT)-poly(dA-dT) to the binding reaction inhibited the formation of the retarded bands, while poly(dI-dC)-poly(dI-dC) did not. In various organs and throughout seed maturation period, proteins with invariable binding specificities were detected, and these binding proteins met some operational criteria for high-mobility-group (HMG) proteins. These results suggest that leguminous seed AT-binding proteins reported on several seed storage protein genes may be HMG-like proteins which are present ubiquitously in plant organs.

Base Sequence↗

PubMed1993

Fibrinolytic components in fetal membranes and amniotic fluid.

OBJECTIVE: We evaluated fibrinolytic components in plasma and amniotic fluid of pregnant women and in postpartum fetal membranes. STUDY DESIGN: Fibrinolytic parameters in amniotic fluid and plasma were measured by means of enzyme-linked immunosorbent assays. Fetal membranes collected after spontaneous labor at term were analyzed by immunohistochemical methods with immunospecific antibodies against fibrinolytic components. RESULTS: Amniotic fluid contained high plasminogen activator inhibitor-1 concentrations but had low activity. Strong staining for plasminogen activator inhibitor-1 and vitronectin was observed in chorionic trophoblasts and moderate staining in decidual connective tissue. Strong staining for plasminogen activator inhibitor-2 was seen in decidual cells. Although prominent staining of plasminogen activators and plasminogen were observed in the amniotic epithelium, virtually no plasminogen activator inhibitor-1, plasminogen activator inhibitor-2, or alpha 2-plasmin inhibitor staining was detected. CONCLUSION: The delicate balance of fibrinolytic activators and inhibitors in fetal membranes and amniotic fluid may contribute to the triggering of membrane rupture at term.

Amniotic Fluid↗

PubMed1993

Effects of electrical stimulation or local anesthesia of the rabbit's hypothalamus on the acute phase response.

The effects of electrical stimulation of the rostral hypothalamic region on the acute phase response (APR) were examined in rabbits. As indicators of APR, we measured changes in the plasma concentrations of iron, zinc, copper, and fibrinogen and changes in the red and white blood cell counts. Electrical stimulation of the rostral hypothalamic region near the preoptic and anterior hypothalamic region did not induce any aspect of the APR. However, stimulation near the anteroventral portion of the third ventricle (AV3V) induced responses that were, in part, opposite to those observed in the APR: an increase in the plasma concentration of zinc and a decrease in the circulating leukocyte count. Microinjections of procaine into the brain regions near the AV3V did not induce any changes in the plasma levels of trace metals and fibrinogen but increased the circulating leukocyte count. These results suggest that nonspecific stimulation or inhibition of the rostral hypothalamic region does not induce APR.

Acute-Phase Reaction↗

PubMed1993

Febrile and metabolic tolerance to endotoxin and human recombinant interleukin-1 beta in rabbits.

We investigated whether or not tolerance of the febrile and metabolic responses to human recombinant interleukin-1 beta (IL-1 beta) develops in rabbits. Febrile tolerance to bacterial endotoxin was induced by daily injections of lipopolysaccharide (LPS, 5.0 micrograms/kg iv). In LPS-tolerant rabbits, the second phase of the biphasic fever induced by intravenous injections of LPS (5.0 micrograms/kg) or IL-1 beta (2.0 micrograms/kg) was significantly reduced. However, the first phase was almost the same as that observed in normal rabbits. Five daily injections of IL-1 beta (2.0 micrograms/kg iv) resulted in the development of tolerance of the febrile response to IL-1 beta. In IL-1 beta-tolerant rabbits, the second peak of the biphasic fever was significantly reduced. In addition, decreases in leukocyte count and plasma zinc induced by intravenous injections of LPS or IL-1 beta were significantly reduced in LPS- or IL-1 beta-tolerant rabbits. However the monophasic fever induced by a smaller dose of IL-1 beta (0.5 microgram/kg iv) and the first peak of the IL-1 biphasic fever were almost the same as those observed in normal rabbits. Febrile responses induced in LPS- or IL-1 beta-tolerant rabbits by intracerebroventricular injections of LPS (5.0 ng) or IL-1 beta (2.0 ng) were similar to those observed in normal rabbits. The present results suggest that tolerance of the febrile and metabolic responses to IL-1 beta is developed after repeated injections of IL-1 beta and that reduced responsiveness to IL-1 beta is partly involved in the development of LPS tolerance.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Phase II study of CPT-11, a new camptothecin derivative, in metastatic colorectal cancer. CPT-11 Gastrointestinal Cancer Study Group.

PURPOSE: A phase II study was conducted to evaluate the antitumor effect and toxicity of CPT-11 in patients with metastatic colorectal cancer. PATIENTS AND METHODS: From December 1989 to March 1991, 67 patients with metastatic colorectal cancer were enrolled in this study. Sixty-three patients were assessable for toxicity and response. Their median age was 57 years (range, 24 to 72). Forty-six patients (73%) had a good performance status of 0 or 1. Fifty-one patients (81%) had received prior chemotherapy. The major sites of metastasis were liver (63%) and lung (44%). CPT-11 was administered as a 100 mg/m2 weekly intravenous infusion, or as 150 mg/m2 every 2 weeks. The dose was reduced based on the grade of leukopenia and diarrhea, if necessary. RESULTS: A partial response was obtained in 17 of 63 assessable patients (27%; 95% confidence interval, 16% to 38%). The response rate in patients with prior radiotherapy or chemotherapy was 25% (13 of 52). Liver metastases showed a 15% (six of 40) response and lung metastases showed a 39% (11 of 28) response. The median duration of partial response was 127 days (range, 49 to 353) and the median overall duration of response was 208 days (range, 99 to 381). The major toxicities (> or = grade 3) were leukopenia (16%), diarrhea (13%), nausea and vomiting (13%), and alopecia (11%). Adverse effects were generally well tolerated and reversible. Treatment could be continued on an outpatient basis for patients without severe toxicity. Hemorrhagic cystitis was not encountered in this study. CONCLUSION: CPT-11 showed promising antitumor activity against metastatic colorectal cancer that was resistant to prior therapy. Further clinical trials of combination chemotherapy using CPT-11 are justified.

Adult↗

PubMed1993

Protein kinase activity associated with the IME2 gene product, a meiotic inducer in the yeast Saccharomyces cerevisiae.

The IME2 gene product (Ime2) is required for entry into meiosis and sporulation in S. cerevisiae. It has been predicted to be composed of two domains, an amino-terminal domain with homology to protein kinases and a carboxy-terminal acidic domain. The Ime2 was identified in extracts of meiotic cells carrying multi- but not low-copy IME2 in immunoblot analysis using an Ime2-specific antibody. Immune complexes were found to phosphorylate Ime2 and several exogenous proteins. Low-copy plasmids expressing truncated Ime2 proteins that lack part of or the entire carboxy-terminal domain enabled cells to undergo sporulation even under a certain repressive nutritional condition. These cells contained increased levels of protein kinase activity compared with control cells. These results suggest that the amino-terminal domain has a protein kinase activity and that the acidic tail is not essential for either the kinase activity or sporulation but serves in a negative role. An Ime2-beta-galactosidase fusion was shown by immunofluorescence microscopy to be localized predominantly to the nucleus, suggesting a nuclear function of Ime2.

Antigen-Antibody Complex↗

PubMed1993

[Long-term results and indications of intraurethral stents in elderly patients with prostatic hypertrophy complaining of urinary retention].

Thirty-two elderly male patients with benign prostatic hypertrophy complaining of urinary retention were treated by polyurethane intraurethral stents. All of them were unfit for prostatic surgery due to the presence of several complications, and had been indwelt with a urethral balloon catheter. Cystometry before stent insertion was performed in 23 of the 32 patients. Eleven patients showed overactive bladder, 5 patients normal bladder, and 7 patients underactive bladder. Duration of stent indwelling ranged from 2 days to 22 months (mean 6.7 months), and stent could successfully function for more than 6 months in 20 of the 32 patients (62.5%). Nine of these 20 patients (45%) could keep continence of urine, and urinary tract infections improved in 7 of these 20 patients (35%). The stent failed in 4 of the 5 patients who had had previous operations for prostatic hypertrophy. In a comparison of the findings of urodynamic study prior to insertion of stent with the results of the stent, the results were significantly better in the patients with overactive or normal bladder than in those with underactive bladder (p < 0.05, chi-square test). Bladder stone formation was found in one patient and was the only complication among the 32 patients. In conclusion, stent placement without incontinence or urinary tract infection can be successful for more than 6 months in patients who do not have an underactive bladder and who had not had a previous prostatic operation.

Aged↗