Search PubMed⌕ Search

Biomedical subjects

Y Sakata

Publications and source records attributed to Y Sakata.

At least 109 records · Page 6Linked to original sources
PubMed1999

Inhibition of tumor necrosis factor-alpha with anti-diabetic agents.

It has recently been indicated that tumor necrosis factor-alpha (TNF-alpha) production is increased under chronic hyperglycemia and TNF-alpha has harmful effects on insulin sensitivity and possibly on chronic diabetic complications. Therefore it will be favorable for diabetes treatment if anti-diabetic agents also have anti-TNF-alpha activities. In this study, we have investigated effects of hypoglycemic sulfonylureas (gliclazide and glibenclamide) and a thiazolidinedione (troglitazone) on lipopolysaccharide-induced TNF-alpha production, which was evaluated by immunoassay and bioassay, in vivo using mice and partly in vitro using human peripheral blood mononuclear cells. Gliclazide significantly inhibited TNF-alpha production in vivo and also in vitro at a concentration of 10(-3) mol/l. However, glibenclamide had neither effect on TNF-alpha production nor action. On the other hand, troglitazone inhibited action rather than production of TNF-alpha in vivo. In vitro troglitazone (10(-4) mol/l) significantly reduced cytolytic activity of TNF-alpha against LM cells. These results indicate that gliclazide and troglitazone have inhibitory effect on TNF-alpha.

Animals↗
PubMed1999

The effects of prenatal stress on the development of hypothalamic paraventricular neurons in fetal rats.

The present experiments focused on the influence of prenatal stress on the development of neurons of the hypothalamic paraventricular nucleus in the fetal rat, including corticotropin-releasing factor-containing neurons. Prenatal stress was administered by restraining pregnant rats in a small cage for either 30 (30-min stress group) or 240 min (240-min stress group) daily for three days from embryonic day 15 to 17, and the fetal brains were taken on embryonic day 18 for later analysis. Golgi-impregnated neurons of the paraventricular nucleus in the 240-min stress group revealed that the total length of the processes was significantly shorter than in the control (unstressed) and 30-min stress groups. In addition, the 240-min stress group showed an increase in the number of apoptotic cells in the fetal paraventricular nucleus. On the other hand, Golgi-impregnated neurons of the paraventricular nucleus in the 30-min stress group had a greater degree of cell differentiation as manifested by an increase in both the number of branch points and the total length of the processes from the cell body. Furthermore, the fetal paraventricular nucleus in the 30-min stress group showed enhanced corticotropin-releasing factor messenger RNA expression, while the varicosities of corticotropin-releasing factor-containing axons at the median eminence revealed more matured morphology such as shorter intervals between the varicosities. These findings suggest the duration-dependent effects of prenatal stress on the development of fetal hypothalamic paraventricular nucleus neurons, including corticotropin-releasing factor-containing neurons: long-lasting stress causes neurotoxic changes of fetal paraventricular nucleus neurons, whereas short-lasting stress facilitates the development of these fetal brain neurons. These morphological changes induced by prenatal stress may contribute to behavioral changes of the offspring after birth.

Animals↗
PubMed1999

Significant association of HLA-B and HLA-DRB1 alleles with cleft lip with or without cleft palate.

Nucleotide sequence level typing of HLA-B, -DRB1, and -DPB1 alleles was performed on Japanese patients with cleft lip with or without cleft palate (CL/P). Two HLA-B alleles, B*1501 and B*5101, showed a significant positive association with CL/P. The increase of B*1501 was evident in female patients (OR=3.6, Pc=0.003), whereas the increase of B*5101 was evident in male patients (OR=3.7, Pc < 0.001). One HLA-DRB1 allele, HLA-DRB1*0802 also showed an increase in CL/P patients. Conversely, HLA-B*4403 and DRB1*1302 were not observed in the patient group (Pc=0.01 and Pc=0.02, respectively). No HLA-DPB1 alleles showed significant association with CL/P. Thus, the present study indicates that HLA alleles, or closely linked loci, may be involved in the pathogenesis of CL/P.

Alleles↗
PubMed1999

Phase II study of docetaxel in patients with metastatic pancreatic cancer: a Japanese cooperative study. Cooperative Group of Docetaxel for Pancreatic Cancer in Japan.

Docetaxel has been reported to show promising anti-tumour activity in pancreatic ductal cancer (PC). This study was conducted to evaluate the activity and toxicity of moderate-dose (60 mg m(-2)) docetaxel in Japanese chemo-naive patients with measurable metastatic PC. The patients had a performance status of 0-2. They received docetaxel intravenously over a 1- to 2-h period without any premedication for hypersensitivity reactions. This treatment was repeated every 3-4 weeks with dose adjustments based on the toxic effects observed. Twenty-one patients were eligible and treated with docetaxel. The median number of courses was 2 (range, 1-4). None of the patients achieved an objective response; seven showed no change and 13 showed progressive disease. In one patient, the response was not assessable because of early death. The median survival time for all patients was 118 days. The main grade 3-4 toxicities by patient were leucocytopenia (67%) and neutropenia (86%). Other grade 3-4 toxicities included anaemia (10%), thrombocytopenia (5%), nausea/vomiting (29%), anorexia (29%), GOT/GPT increase (10%), alkaline phosphatase increase (14%), malaise/fatigue (33%) and alopecia (24%). In conclusion, docetaxel, administered on this schedule, did not show significant anti-tumour activity in patients with metastatic PC.

Adult↗
PubMed1999

Evaluation of endoscopic variceal ligation in prophylactic therapy for bleeding of oesophageal varices: a prospective, controlled trial compared with endoscopic injection sclerotherapy.

BACKGROUND: To evaluate the efficacy of endoscopic variceal ligation (EVL) in prophylactic therapy for oesophageal varices, we performed a randomized prospective trial to compare the recurrence of oesophageal varices treated by EVL with those treated by endoscopic injection sclerotherapy. METHODS: Fifty patients with liver cirrhosis were divided into two groups at random, after informed consents were obtained, to receive prophylactic therapy for bleeding of oesophageal varices. Group 1 patients underwent sessions of sclerotherapy with 5% ethanolamine oleate used as the sclerosant. Group 2 patients underwent EVL followed by one or two sessions of sclerotherapy. RESULTS: During the 18 month follow-up period, both the recurrence rate in group 2 (56%) and the incidence of bleeding (20%) were significantly higher compared with group 1 (recurrence rate 16%, bleeding 0%). CONCLUSIONS: This result indicates that EVL is not effective for prophylactic therapy for oesophageal varices in liver cirrhosis.

Esophageal and Gastric Varices↗
PubMed1999

Possible involvement of interleukin-1 in cyclooxygenase-2 induction after spinal cord injury in rats.

A standardized compression injury of rat spinal cord brought about a time-dependent biphasic production of thromboxane A2 (detected as thromboxane B2) and prostaglandin I2 (detected as 6-ketoprostaglandin F1alpha). Thromboxane B2 was predominant during the first 1 h, whereas the 6-ketoprostaglandin F1alpha level exceeded that of thromboxane B2 at 8 h postinjury. As examined by inhibitor experiments and northern blotting, cyclooxygenase-1 was responsible for the first phase, and cyclooxygenase-2 was involved in the second phase. On compression injury the levels of interleukin-1alpha and -1beta detected as mRNA and protein increased and peaked at 2-4 h. Injection of exogenous interleukin-1alpha into the spinal cord resulted in an increase of cyclooxygenase-2 mRNA content and a predominant production of 6-ketoprostaglandin F1alpha resembling the second phase of eicosanoid production. Concomitantly, extravascular migration of polymorphonuclear leukocytes was enhanced after the interleukin-1alpha injection. These cells together with vascular endothelial cells and glial cells were stained positively with an anti-cyclooxygenase-2 antibody. The results suggest that the immediate eicosanoid synthesis after spinal cord injury was due to the constitutive cyclooxygenase-1 and the delayed synthesis of eicosanoids was attributable to the induction of cyclooxygenase-2 mediated by interleukin-1alpha.

Animals↗
PubMed1999

A case of advanced esophageal cancer showing a long-term complete response with chemotherapy with nedaplatin alone.

We describe a case of advanced esophageal cancer treated successfully by chemotherapy with nedaplatin alone. A 60-year-old male with type 2 advanced esophageal cancer, which was located in the upper part of the esophagus and had invaded adjacent organs, was treated with nedaplatin 150 mg/body (100 mg/m2) given intravenously every 4 weeks from January 6, 1991. He achieved a partial response (PR) and was discharged in March 1991. Subsequently, he received nedaplatin 75 mg/body in an out-patient setting almost every month until August 1992. Toxicities were tolerable and included mild thrombocytopenia and nausea/vomiting. From serial evaluation in October 1993, the esophageal tumor was not observed. After 7 years since initial chemotherapy was administered, he still survives without the disease.

Antineoplastic Agents↗
PubMed1999

Phase II study of raltitrexed (Tomudex) in chemotherapy-pretreated patients with advanced colorectal cancer. Tomudex Cooperative Study Group.

Raltitrexed (Tomudex), a novel folate-based inhibitor of thymidylate synthase, has demonstrated anti-tumour efficacy comparable with 5-fluorouracil and leucovorin in patients with advanced colorectal cancer (CRC). This phase II study was conducted to evaluate the anti-timor efficacy and tolerability of raltitrexed in patients with advanced CRC who had received one previous chemotherapy regimen. Raltitrexed was administered at a dose of 3.0 mg/m2 i.v. over 15 min once every 3 weeks. Of 43 eligible patients, 53% had colon cancer and 47% rectal cancer. Objective responses were observed in 16% of patients [95% confidence interval (CI): 7-31%; seven partial responses). The median duration of response was 101 days (range: 45-239 days), the median overall duration of response was 145 days (range: 104-302 days) and the median survival was 11.6 months (95% CI: 9.4-14.7 months). Liver metastases showed a 17% (three of 18) response rate and lung metastases a 12% (three of 25) response rate. Adverse events of grade 3 or 4 reported for more than 5% of patients were neutropenia (23%), leukopenia (9%), reversible SGPT increase (7%) nausea/vomiting (19%), anorexia (14%), asthenia (9%) and hypotension (7%). Grade 3 or 4 diarrhea, stomatitis and alopecia were not observed. In summary, raltitrexed had an acceptable toxicity profile and promising anti-tumor activity against advanced CRC in patients who had received prior chemotherapy. Further clinical trials of combination chemotherapy using raltitrexed are warranted.

Adult↗
PubMed1999

[Steroid pulse therapy and vital prognosis among pediatric cancer patients with sepsis].

The usefulness of glucocorticosteroid therapy in patients with sepsis has been controversial. We investigated the effect of steroid pulse therapy on the vital prognosis of pediatric patients with sepsis and followed the vital status up to one month after the use of pulse therapy. We reviewed the medical records of 89 pediatric cancer patients with sepsis treated at our hospital between 1988 and 1996. The risks of potential predictors were estimated by calculating crude and adjusted relative risk (RR). The total cumulative death was 33/89 (25%). All patients treated with steroid pulse therapy died (12/12). Patients with either interstitial pneumonia (IP), infection-associated hemophagocytic syndrome (IAHS) and graft-versus-host disease (GVHD) showed a significantly higher cumulative death (57% (12/21) vs 31% (21/68), p = 0.03). Increased risk of cumulative death was suggested for the older age group, inappropriate antimicrobial therapy, and the conditions requiring steroid pulse therapy (IP, IAHS, and GVHD), (crude RR were 1.6, 1.6, and 1.9, respectively). However, when adjusted for pulse therapy, these three factors no longer indicated risk elevation, (adjusted RR = 1.2, 1.2, and 0.3, respectively). On the other hand, steroid pulse therapy per se was independently associated with increased risk of cumulative death (crude RR = 3.6, adjusted RR = 10). Thus, the risk of the conditions requiring steroid pulse therapy (IP, IAHS, and GVHD) firstly observed could be regarded as an apparent association due to steroid pulse therapy.

Child↗
PubMed1999

[Plasmodium falciparum infection in a 8-year old boy].

A 8-year old Japanese boy who returned from Tanzania was admitted to our hospital because of fever, vomiting, and headache. He was diagnosed as a Plasmodium falciparum infection verified by a blood smear. He was treated with quinine and halofantrine, and recovered completely. Malaria infection should be considered when patients return from Malaria endemic areas.

Child↗
PubMed1999

An early phase II study of oral S-1, a newly developed 5-fluorouracil derivative for advanced and recurrent gastrointestinal cancers. The S-1 Gastrointestinal Cancer Study Group.

5-Fluorouracil (5-FU) or a 5-FU derivative 1-(2-tetrahydrofuryl)-5-fluorouracil (FT) has been widely prescribed for patients with gastrointestinal cancer. However, the phosphorylation of 5-FU in the digestive tract causes gastrointestinal toxicities. 5-FU is also rapidly degraded to alpha-fluoro-beta-alanine after contact with dihydropyrimidine dehydrogenase (DPDase) which is mainly present in the liver. Therefore, to overcome these metabolic events, S-1, an antitumor agent was developed, based on the biochemical modulation of FT by 5-chloro-2,4-dihydroxypyridine (CDHP) and potassium oxonate (Oxo), in a molar ratio of 1:0.4:1. The antineoplastic effect of S-1, was examined in Japanese patients with advanced gastric (G) or colorectal (C) cancer in a multicenter early phase II study involving 24 centers throughout Japan. The patients were prescribed a minimum of 2 courses of S-1 orally, with each course consisting of 75 or 50 mg (in terms of FT) twice a day for 28 days followed by withdrawal for 2 weeks. Thirty-one patients with G and 31 C were entered into this study. The clinical response and extent of toxicity were evaluated in G 28 and C 30 cases, respectively. Nine (32.1%) G patients and 14 (46.7%) C patients had been treated previously with other anticancer drugs. In G patients, there was a 53.6% (15/28) and in C patients a 16.7% (5/30) response rate (90% confidence interval G 38.4-68.1% and C 8.4-30.5%) with 15 (53.6%) (G) and 5 (16.7%) (C) partial responses (PR), and these responses persisted for 79 days (G) and 120 days (C) (median value). In particular, the response rate for the primary lesion was 27.8% (5/18) (G) and 33.3% (1/3) (C). No change (NC) in the disease was observed in 4 (14.3%) (G) and 13 (43.3%) (C) patients, and in 6 (21. 4%) (G) and 7 (23.3%) (C) the disease progressed (PD). At the time of analysis, the median survival was 298 days (G) and 358 days (C). Major adverse effects consisted of gastrointestinal symptoms and myelosuppression while toxicities of grade 3 or more occurred in 35. 7% (10/28) (G) and 33.3% (10/30) (C). Based on these data, S-1 is considered to have positive effects in patients with advanced gastrointestinal cancer.

Adult↗
PubMed1999

Phase II study of a combination of irinotecan and cisplatin against metastatic gastric cancer.

PURPOSE: A phase II study of a combination chemotherapy regimen of cisplatin (CDDP) and irinotecan (CPT-11) was conducted to assess its efficacy and feasibility in patients with metastatic gastric cancer. PATIENTS AND METHODS: Eligibility criteria included the following: (1) histologically proven gastric cancer with measurable metastatic lesions, (2) performance status of 2 or less, (3) age of 75 years or younger, (4) one or no prior chemotherapy regimens, (5) adequate bone marrow, liver, renal, and cardiac functions, and (6) written informed consent. The treatment consisted of CPT-11 (70 mg/m2) on day 1 and day 15 and CDDP (80 mg/m2) on day 1, repeated every 4 weeks. RESULTS: Forty-four patients were entered onto the study. The overall response rate was 48% (21 of 44 patients, 95% confidence interval [CI], 33% to 63%) and included one complete remission (2%). The response rate of the patients who had not received prior chemotherapy was 59% (17 of 29 patients, 95% CI, 39% to 77%). The median survival time was 272 days for all patients and 322 days for the 29 patients who had not received prior chemotherapy. Grade 4 neutropenia was observed in 25 patients (57%), and grade 3 or 4 diarrhea was observed in nine patients (20%). Other adverse reactions were mild. No treatment-related deaths occurred. CONCLUSION: This combination chemotherapy regimen is active and well tolerated. It may be an appropriate regimen for future phase III trials.

Adenocarcinoma↗
PubMed1999

Structural studies of the interactions of normal and abnormal human plasmins with bovine basic pancreatic trypsin inhibitor.

Catalytic activity of human plasmin is inhibited by bovine basic pancreatic trypsin inhibitor (BPTI, also known as aprotinin). In spite of increased interest in the function of BPTI as an inhibitor of plasmin, the 3-D structure of the plasmin-BPTI complex has not yet been determined. Therefore, in the present paper, the structure of the plasmin-BPTI complex was constructed by the homology modeling method, which provided information about the high affinity of plasmin for BPTI. Moreover, normal mode analyses of free plasmin, free BPTI and the plasmin-BPTI complex were carried out to investigate the changes in dynamics following complex formation. After study of the plasmin-BPTI interaction, we also investigated the binding of BPTI with abnormal plasmin, theoretically and experimentally. The result showing that BPTI binds to abnormal plasmin in the same way as it does to normal plasmin supports the previous finding that the difference between normal and abnormal plasmins is very small and that the abnormality is localized to the catalytic site.

Algorithms↗
PubMed1999

Aspergillus osteomyelitis in a child who has p67-phox-deficient chronic granulomatous disease.

Here we describe Aspergillus osteomyelitis of the tibia in a 9-year-old boy who has an autosomal recessive form of chronic granulomatous disease (CGD). The patient showed a p67-phagocyte oxidase (phox) deficiency, which is rare type of CGD in Japan. The initial treatment which consisted of surgical debridement and antibiotic therapy with amphotericin B (AMPH), did not control the infection. Aspergillus fumigatus (A. fumigatus) pure isolated from drainage fluid and necrotic bone tissue demonstrated less susceptible to antifungal agents, including AMPH, fluconazole and flucytosine. Recombinant interferon gamma was then administrated, and it was effective in controlling the course of severe invasive aspergillosis. This report indicates the use of interferon gamma might be helpful in control for Aspergillus osteomyelitis of the tibia in a child with CGD demonstrated p67-phox deficiency refractory to conventional therapy with AMPH.

Amphotericin B↗
PubMed1999

Glucocorticoid enhances interleukin-1-induced pressor response in freely moving rats through its effect on nitric oxide release.

We investigated whether changes in nitric oxide (NO) release might be responsible for the modulation by glucocorticoids of the pressor response to i.p. injection of interleukin-1beta (IL-1beta) in freely moving rats. In such rats, IL-1beta (10 microgram/kg) induced a biphasic pressor response, with a rise in the plasma concentration of NOx (NO2(-) and NO3(-): metabolites of NO) during the second phase. Systemic pretreatment with an exogenous glucocorticoid, dexamethasone (0.5 mg/kg), enhanced the second phase of the pressor response and completely suppressed the increase in plasma NOx. Treatment with Nomega-nitro-L-arginine methyl ester (L-NAME, a nonspecific NO synthase inhibitor), enhanced the pressor response while attenuating the increase in plasma NOx. After bilateral adrenalectomy, IL-1beta induced a smaller pressor response, but a larger increase in plasma NOx; dexamethasone reversed these changes. Our results suggest that endogenous NO moderates the pressor response to IL-1beta in freely moving rats, and that glucocorticoids enhance the IL-1beta-induced pressor response at least in part by reducing endogenous NO release.

Adrenalectomy↗
PubMed1999

[A late phase II clinical study of RP56976 (docetaxel) in patients with advanced or recurrent gastric cancer: a cooperative study group trial (group B)].

A late phase II clinical study of RP56976 (docetaxel) in patients with advanced or recurrent gastric cancer was performed to evaluate the anti-tumor activity and clinical toxicity as a multicenter cooperative trial. Docetaxel was administered intravenously at a dose of 60 mg/m2 every 3-4 weeks. Of 72 patients enrolled, 63 patients were eligible and 59 patients were evaluable for response. The anti-tumor effects obtained complete response (CR) in one patient partial response (PR) in 13, minor response (MR) in 3, no change (NC) in 20, and progressing disease (PD) in 22 patients. The overall response rate in 59 patients was 23.7% (14/59). For 14 CR or PR cases, a response appeared 10 to 107 days (median 33.5 days) and 1 to 8 (median 2) times of dosing after the initial administration. The response rate was 9.5% in the primary tumor, 31.3% livers, 50.0% abdominal tumor, and 24.1% lymph nodes, respectively. The major adverse reactions were gastrointestinal symptoms including nausea/vomiting, anorexia, fatigue, alopecia and fever. Leukocytopenia and neutrocytopenia were also observed with a high incidence, but they recovered after 8 days from the nadir. The results show that docetaxel is an effective anti-tumor agent for advanced or recurrent gastric cancer. It is necessary to conduct another clinical trial by concomitant administration with other anti-tumor agents.

Adenocarcinoma↗
PubMed1999

[Current concept of the pathogenesis of autoimmune type 1 diabetes mellitus].

In type 1 diabetes, the beta cell is selectively destroyed by T lymphocytes in a genetically susceptible individual. Susceptible HLA-class II molecules which have low binding affinity with putative beta cell antigens may fail in induction of self-tolerance. beta cell-reactive T cells may expand and infiltrate around the islet (benign insulitis) by stimulation with environmental factors through molecular mimicry and/or beta cell antigens per se. Benign insulitis may develop to destructive insulitis under overexpression of Th1 cytokines, which may be affected by non-MHC genes. Immune interventions to shift a cytokine balance to Th2 dominance in the insulitis lesion may be most realistic approach to suppress development of type 1 diabetes after the induction of autoimmunity.

Animals↗