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Biomedical subjects

T Ishioka

Publications and source records attributed to T Ishioka.

At least 19 recordsLinked to original sources
PubMed2005

Toxicity and roles of reactive oxygen species.

The history of studies in biology regarding reactive oxygen species (ROS) is approximately 40 years. During the initial 30 years, it appeared that these studies were mainly focused on the toxicity or microbicidal-related agents of ROS. However, recent studies have identified another action regarding oxidative signaling, other than toxicity of ROS. Basically, it is suggested that ROS are reactive, and degenerate to biomacromolecules such as DNA and proteins, leading to deterioration of cellular functions as an oxidative stress. On the other hand, recent studies have shown that ROS act as oxidative signaling in cells, resulting in various gene expressions. For example, NADPH oxidase, a major source of superoxide radicals (O(2)(-)), expresses in various tissues such as leukocytes and cardiovascular systems, and ROS derived from the enzyme play important roles in cell proliferation, differentiation, and cell death. In this review, we have focused on and described the basic properties, toxicity, and roles of ROS.

Animals↗
PubMed2001

Relationship between serum tumor necrosis factor-alpha and insulin resistance in obese men with Type 2 diabetes mellitus.

We analyzed serum concentrations of tumor necrosis factor-alpha (TNF-alpha) for their role in insulin resistance in 12 obese men with untreated Type 2 diabetes mellitus and in 6 age-and BMI-matched obese controls. Insulin resistance was expressed using the homeostasis model assessment (HOMA-R). Six of the patients were insulin-resistant (HOMA-R>5.0), while six were not (HOMA-R</=3.0). Serum levels of TNF-alpha were higher in patients with insulin resistance (4.19+/-0.96 pg/ml) than in patients without insulin resistance (2.52+/-1.64 pg/ml) and in controls (2.03+/-1.21 pg/ml). Fasting serum concentrations of insulin and HOMA-R were higher in patients with insulin resistance (16.2+/-5.0 and 6.30+/-1.0 IU/ml, respectively) than in patients without insulin resistance (7.3+/-2.2 and 2.4+/-0.6 IU/ml) and in controls (8.0+/-2.9 and 1.8+/-0.6 IU/ml). These data suggest that high levels of serum TNF-alpha in patients with insulin resistance are related to high levels of fasting insulin and HOMA-R. We conclude that TNF-alpha may be involved in the pathogenesis of Type 2 diabetes mellitus in obese men. The importance of this investigation is that the subjects recruited in the study are BMI matched, because human obesity is associated with an increased TNF-alpha mRNA expression in adipose tissue.

Adult↗
PubMed2001

Vibrational study on structural transitions of potassium pelargonate CH3(CH2)7CO2K.

Anhydrous potassium pelargonate (KC9) undergoes four thermal transitions from room temperature to 450 degrees C. A normal mode analysis was made for the molecule in phase I at room temperature and the molecule was considered to have an all-trains conformation. With increasing temperature, partial melting of the alkyl chains occurred in phase II and complete melting was observed in phase III, as confirmed by vibrational spectra. In addition, orientational disorder of the carboxylate groups was suggested in phase II. This transition behavior of potassium pelargonate was compared with the behavior of nonane and pelargonic acid.

Fatty Acids↗
PubMed2000

Infrared and XAFS study on structure and transition behavior of zinc stearate.

Structure and transition behavior of zinc(II) stearate crystal were investigated by infrared and XAFS spectroscopies. Structure of zinc stearate at room temperature was estimated as follows. From XAFS analysis, the coordination number of the carboxylate groups around the zinc atom was evaluated as 4 and the Zn-O distance as 1.95 A. Based on the infrared spectrum and a normal mode analysis, the conformation of the alkyl chain was confirmed as all-trans and the sub-cell packing was considered as parallel type, and also the coordination form of the carboxylate groups was determined as bridging bidentate type. As increasing temperature, zinc stearate has a solid liquid phase transition at 130 degrees C. At the transition, the alkyl chains goes into liquid like state as reported by Mesubi but the coordination structure was confirmed to be maintained.

Molecular Conformation↗
PubMed2000

Anti-androgenic activity of substituted azo- and azoxy-benzene derivatives.

Substituted phenylazo and phenylazoxy compounds were systematically prepared and their anti-androgenic activity was measured in terms of (1) the growth-inhibiting effect on an androgen-dependent cell line, SC-3, and (2) the binding affinity to nuclear androgen receptor. Generally, azo/azoxy compounds showed cell toxicity, and the growth-inhibiting effects on SC-3 cells correlated with the toxicity. However, some compounds, including 4,4'-dinitroazobenzene (25), 4,4'-dimethoxyazobenzene (33), and 2,2'-dichloroazoxybenzene (47), possessed potent anti-androgenic activity without apparent cell toxicity.

Androgen Antagonists↗
PubMed1998

Utilization of proteinase K-treated cells as lipopolysaccharide antigens for the serodiagnosis of Helicobacter pylori infections.

We have evaluated the use of proteinase K (PK)-treated cells isolated from Helicobacter pylori as lipopolysaccharide (LPS) antigens in an immunoblot assay and an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of H. pylori infection. The sera from patients with chronic gastritis, gastric ulcer, duodenal ulcer or gastric cancer, and from healthy adults with or without H. pylori infection were assayed with three commercial serodiagnostic kits (HM-CAP, Helico-G, and G.A.P. II) and novel methods relying on the use of PK-treated cells. The PK-treated cells used in these assays were selected on the basis of their possibility to possess a common epitope in the O-polysaccharides of H. pylori, which is known to be highly immunogenic in humans. Of the sera from these patients, 71-94% were positive with the commercial kits, 97% with immunoblot assay, and 90% with ELISA. On the other hand, of the healthy adults infected with H. pylori, 72-97% were positive with the commercial kits, 86% with immunoblot assay, and 72% with ELISA. PK-treated cells that did not contain the common epitope were unsuitable as an antigen for immunoblot assay or ELISA. Furthermore, the reactivity of these sera reacted specifically with H. pylori PK-treated cells but not with LPSs from other gram-negative bacteria, such as Campylobacter, Proteus, Bordetella, and Salmonella. These results demonstrate that the serological assays relying on the use of H. pylori PK-treated cells possessing a highly antigenic epitope are potentially useful as a serodiagnostic test for H. pylori infection.

Adult↗
PubMed1996

Change of renal function during vancomycin therapy in extremely low birthweight infants.

Twenty extremely low birthweight infants were treated with vancomycin (VCM). Their gestational age was 26.3 +/- 1.4 weeks (range 24.0-28.7 weeks) and their birthweight was 829 +/- 133 g (range 562-900 g). At the time of initial administration of VCM, postnatal age was 29.5 +/- 15.8 days (range 5-54 days). Vancomycin was administered in a dose between 9.3 and 11.0 mg/kg every 12 h for a period of 6.3 +/- 2.4 days (range 4-13 days). Serum and urinary specimens were obtained before and after (within 24 h following the last dose) VCM therapy. Serum creatinine and sodium, and urinary N-acetyl-beta-D-glucosaminidase (NAG) activity, creatinine, sodium, and beta-2-microglobulin (BMG) concentrations were measured. Fractional excretion of sodium (FENa) and NAG index (NAG:creatinine ratio) were calculated. There were no significant differences between the before and after VCM treatment in serum creatinine, urinary BMG concentration, FENa and NAG index. No infant showed any symptoms of renal insufficiency. However, the NAG index and FENa increased after treatment in 1 of 20 infants. Vancomycin is effective and safe in the treatment of serious infections in extremely low birthweight infants.

Acetylglucosaminidase↗
PubMed1996

[A randomized controlled study of post-operative adjuvant therapy in non-small cell lung cancer].

The efficacy of postoperative adjuvant chemo- and chemoimmunotherapy in non-small cell lung cancer was evaluated in a multicentric prospective randomized study. From September 1987 to June 1990, resected lung cancer patients were randomly stratified into three groups. Group A received 2 courses of chemotherapy with CDDP and VDS following operation. Group B was administered UFT daily for 1 year after 2 courses of CDDP. Group C received intrapleural administration of OK-432 after lung resection, then UFT and OK-432 once every 2 weeks for 1 year. Out of 94 cases, analyses were carried out on 87 of eligible cases. The five-year survival rate was 56.8% in stage I (43 cases), 73.3% in stage II (12 cases), 18.8% in stage IIIA (24 cases), 50% in stage IIIB (2 cases) and 33.3% in stage IV (6 cases). The five-year survival rate in group A was 32.2%, 55.2% in group B and 53.9% in group C, and no statistical difference was recognized between 3 groups. But in the cases of noncurative resection, the 5-year survival rate was significantly low in group A compared with Group B or C. Similarly, the cases with low-grade TP (<6.0 g/dl) or low response of PPD skin reaction (< 12mm) showed a significantly low 5-year survival rate only in group A. From these results, it was suspected that aggressive chemotherapy provides no benefit for postoperative lung cancer patients with advanced disease.

Adult↗
PubMed1995

Topographic study of Helicobacter pylori and HLA-DR antigen expression on gastric epithelium.

Helicobacter pylori and HLA-DR antigen expression on gastric epithelium, identified by an indirect immunoperoxidase staining method using monoclonal antibodies against H. pylori and HLA-DR antigens, were studied topographically. Fifty-nine biopsy specimens from 41 patients who had neither gastric cancer nor peptic ulcers were examined. H. pylori was observed predominantly over or on the surface epithelium, while HLA-DR antigens were frequently expressed on the epithelium of the isthmus region. These observations led to the conclusion that there was no direct topographic association between H. pylori and epithelial HLA-DR expression. However, the frequency of HLA-DR expression in H. pylori-positive (28/29) specimens was significantly higher than that in H. pylori-negative (18/30) specimens (P < 0.01). Furthermore, a greater number of H. pylori was associated with a stronger expression of HLA-DR antigens (P < 0.001). We conclude that H. pylori is indirectly related to HLA-DR expression on gastric epithelium. H. pylori is the first microbial agent that has been suggested to be associated with epithelial HLA-DR expression in the human gastrointestinal tract.

Adolescent↗
PubMed1993

[Nutritional assessment and rapid turnover protein in the elderly].

Nutritional assessment with respect to rapid turnover protein (RTP) in the elderly was performed in 22 outpatients (7 males and 15 females, mean age 77 years) who suffered from slight illnesses such as mild hypertension and osteoporosis. Their nutritional parameters were almost within the normal range, judging from body mass index (BMI) and their plasma levels of total protein, albumin, lipids and RTP (transferrin, pre-albumin and retinol-binding protein). Statistically, BMI had a significantly positive correlation with subcutaneous fats and total protein and had a significantly negative correlation with HDL-cholesterol. Retinol-binding protein had a significantly positive correlation with prealbumin, ferritin and vitamin A. Conversely, in 12 bedridden patients the nutritional status was very poor, with their plasma levels of the above markers being significantly lower than those of the controls. We administered an enteral diet (EWH330) to 10 bedridden patients in an effort to restore their nutritional status. As a result, their nutritional parameters, especially RTP showed a significant increase after 4 and 8 weeks of the administration of EWH330. These results suggest that RTP is a very sensitive parameter of nutritional assessment in the elderly.

Aged↗
PubMed1992

Expression of MHC class II antigens (HLA-DR, -DP, and -DQ) on human gastric epithelium.

Class II antigen expression on gastric epithelium was investigated using an immunoperoxidase method in relation to the degree of inflammatory cell infiltration in the lamina propria. Sixty-six biopsy specimens from 43 patients with chronic gastritis were examined. The frequency of HLA-DR expression in specimens with cell infiltration was 94%, while that in specimens without cell infiltration was 24%. There was significant difference in the frequency of HLA-DR expression between the two groups (P less than 0.01). HLA-DR was most intensely expressed in the glandular neck portion. The frequency and extent of class II antigen expression on gastric epithelium with cell infiltration were in the following order: DR greater than DP greater than DQ. The extent of DR and DP, but not DQ expression generally paralleled the degree of cell infiltration. Intestinal metaplasia was found in 13 specimens. In the area of intestinal metaplasia, epithelial class II staining was absent except for one specimen. These results suggest that the respective genes of three class II antigens are regulated by different mechanisms and that an immunological mechanism plays a role in the pathogenesis of gastritis.

Epithelium↗
PubMed1992

[Use of the newly designed long-handled forceps for respiratory surgery].

We report on use of the newly designed long-handled forceps for respiratory surgery. The forceps have a curved-end in the same plane as its handles. This contributes to the easier clamping of vessels running horizontally in the deep fields. It is very useful not only in thoracic surgery, such as respiratory and esophageal surgery, but also in pelvic surgery.

Equipment Design↗
PubMed1990

[A case of two-chambered right ventricle complicating severe cyanosis due to tricuspid regurgitation and patent foramen ovale].

A 63-year-old female of two-chambered right ventricle (TCRV) associated with tricuspid regurgitation (TR), patent foramen ovale (PFO) and small ventricular septal defect (VSD) underwent corrective surgery successfully. She suffered severe heart failure and cyanosis with 47.7% of right-to-left shunt through PFO. The VSD was so small that no significant shunt was shown in catheterization data. Operative findings suggested that TR was caused by elongation of the chorda as a consequence of long-term pressure load of right ventricular inflow chamber. Among reported cases of TCRV, the present case is the oldest one who underwent corrective surgery successfully.

Female↗