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T Tanigawa

Publications and source records attributed to T Tanigawa.

At least 55 records · Page 3Linked to original sources
PubMed1999

Characteristics of the production of active oxygen species from adherent and non-adherent neutrophils.

Our objective was to evaluate the characteristics of the production of AOS from the neutrophils that had adhered to the endothelial cells, fibronectin or polystyrene, using the method of electron paramagnetic resonance (EPR) spin trapping. Neutrophils and endothelial cells were isolated from human venous blood and umbilical veins, respectively. AOS production from neutrophils was not elicited only by adhesion. The stimulation of adherent neutrophils with phorbol myristate acetate (PMA) induced the production of AOS. The production of AOS from adherent neutrophils to endothelial cells, but not to fibronectin or polystyrene, decreased with the interval time between the adhesion and the stimulation by PMA. The amount of AOS produced by the neutrophils adherent to fibronectin or polystyrene was maintained for one hour after stimulation with PMA, whereas that by suspended neutrophils gradually decreased with the time after stimulation. Results indicate that adherent and non-adherent neutrophils exhibit differing time course of AOS production.

Cell Adhesion↗
PubMed1999

Abnormal Ca2+ release from cardiac sarcoplasmic reticulum in tachycardia-induced heart failure.

OBJECTIVE: In heart failure, little information is available as to the Ca2+ release function of sarcoplasmic reticulum (SR), which plays a major role in cardiac contractile function. Here, we assessed the rapid kinetics of drug-induced Ca2+ release from cardiac SR in combination with a measurement of ryanodine binding in heart failure. METHODS: The SR vesicles were isolated from dog left ventricular (LV) muscles (normal (N), n = 10; pacing induced heart failure (HF), n = 10). The time course of SR Ca2+ release was continuously monitored by a stopped-flow apparatus using arsenazoIII as a Ca2+ indicator, and Ca2+ uptake and [3H]ryanodine binding assays were done using a filtration method. RESULTS: The amount of Ca2+ uptake was reduced in HF to 55% of N (P < 0.05). Even the more marked and earlier appeared decrease was seen in the rate constant and the initial rate of polylysine (PL; a specific release trigger)-induced Ca2+ release (P < 0.05). However, the PL concentration dependency of the initial rate shifted towards lower concentrations of PL in HF than in N ([PL] at half maximum stimulation = 0.13 vs. 0.35 microM). The [3H]ryanodine binding assay revealed a lower Bmax (pmol/mg) in HF than in N (0.91 +/- 0.19 vs. 2.64 +/- 0.59, P < 0.05), but no difference in Kd (nM) (0.95 +/- 0.29 vs. 0.90 +/- 0.11, P = n.s.). The [PL] dependency on the enhancement of [3H]ryanodine binding again showed a shift towards lower [PL] in HF than in N. CONCLUSIONS: In pacing-induced heart failure, the Ca2+ releasing function of SR is disturbed, which may result in an intra-cellular Ca2+ transient that was slowed down.

Animals↗
PubMed1999

A novel water-soluble vitamin E derivative protects against experimental colitis in rats.

This study was designed to investigate the effects of water-soluble vitamin E derivative, 2-(alpha-D-glucopyranosyl)methyl-2,5,7,8-tetramethylchroman-6-ol (TMG), on experimental colitis in rats. Colitis was induced in male Wistar rats weighing 200 grams using an enema of trinitrobenzene sulfonic acid (TNBS) dissolved in 50% ethanol; 1 ml of TMG dissolved in physiological saline (0.2 mg/ml, 2 mg/ml, 20 mg/ml) was injected intraperitoneally every day for 1 week after the enema. The damage score, wet weight of the colon, and increase in body weight were estimated 1 week after the enema of TNBS. Thiobarbituric acid-reactive substances (TBA-RS), an index of lipid peroxidation, and the level of alpha-tocopherol or TMG in the colonic mucosa were measured 1 week after the induction of colitis. As a result, increase in body weight was inhibited by the induction of colitis, although the inhibition was reduced in the group treated with TMG. The damage score, wet weight and TBA-RS were increased significantly in the colitis group; however, they were inhibited by the administration of TMG. The alpha-tocopherol level in the colonic mucosa was reduced by the induction of colitis, wheres TMG could not be detected in the colonic mucosa of rats treated with TMG. These results suggest that TMG is effective for the treatment of colitis in rats induced by TNBS.

Animals↗
PubMed1999

[The effects of fish supplementation of platelet function, count and metabolism in healthy Japanese].

To investigate changes in platelet function, count and metabolism following fish intake among Japanese, we conducted an experimental intervention study of seven healthy Japanese volunteers (4 males and 3 females) aged 28-58 years. We supplemented their diets with an approximate daily intake of 200-400 g fish which is equivalent to about 10 g n3-polyunsaturated fatty acids (about 3.5 g eicosapentaenoic acid plus 5.0 g docosahexaenoic acid) during the 17 days. The study continued until the 23rd day after returning to an ad libitum diet. The proportion of serum n3-polyunsaturated fatty acids increased two-fold on 5th day and three-fold on 15th day of fish supplementation, but decreased to one and a half-fold on the 2nd day and returned to the level before fish supplementation on the 12th day after returning to an ad libitum diet. The proportion of serum n6-polyunsaturated fatty acids decreased by 17% to the level before fish supplementation on the 5th day, 33% on the 15th day of fish supplementation. However, the decrease was only 10% on the 2nd day and the proportion returned to the same level as before fish supplementation on the 12th day after returning to an ad libitum diet. As a result, the serum n3/n6 polyunsaturated fatty acid ratio increased four-fold on the 15th day of fish supplementation, and returned to the baseline level on the 12th day after returning to an ad libitum diet. Platelet counts decreased and the mean platelet volume increased during fish supplementation. Both parameters returned to the level before fish supplementation on the 12th day after returning to an ad libitum diet. The counts and proportion of large type platelets increased significantly during fish supplementation. Although platelet aggregation by ADP (adenosine 5'-diphosphate) did not change significantly, platelet aggregation by collagen tended to decrease during fish supplementation. Platelet factor 4, one of the indices of platelet activity, decreased significantly during fish supplementation. The mean serum triglyceride level declined during fish supplementation, but returned to the level just before fish supplementation on the 2nd day after returning to an ad libitum diet. The mean plasma fibrinogen level tended to decline during fish supplementation and remained lower until the 12th day after returning to an ad libitum diet. Habitual fish intake may attenuate the development of atherosclerosis and prevent ischemic heart disease through suppression of platelet activity, and by reducing platelet counts and serum triglyceride levels.

Adult↗
PubMed1998

Changes in T cell subpopulations in lead workers.

To investigate the effects of lead on the human immune system, we analyzed T cell subpopulations and B (CD19+) cells in peripheral blood in 71 male lead workers. They were engaged in manufacturing lead stearate in a chemical factory, aged 20 to 74 (mean 48) years. Their blood lead concentrations (PbB) were between 7 and 50 (mean 19) micrograms/dl. The control group consisted of 28 "healthy" male volunteers without a history of occupational exposure to lead or other hazardous substances, aged 33 to 67 (mean 55) years. In comparison with the controls, a significant reduction in the number of CD3+CD45RO+ (memory T) cells and a significant expansion in the percentage of CD8+ cells in the lead workers were found. There was a significant positive correlation between the percentage of CD3+CD45RA+ (naive T) cells and PbB in the lead workers. It is suggested that CD45RO+ memory T cells may be most susceptible to the effects of lead on T cell subpopulations.

Adult↗
PubMed1998

Effects of smoking, aromatic amines, and chromates on CD4+ and CD8+ T lymphocytes in male workers.

To investigate effects of smoking, aromatic amines (AAs), and chromates (CRs) on T lymphocyte subpopulations, we measured CD3+, CD4+, and CD8+ T lymphocytes in the peripheral blood of 33 nonexposed workers, 25 AA-use workers, 27 AA-production workers, and 19 CR workers (all subjects were males). The number of CD4+ T lymphocytes in smokers of nonexposed workers was significantly larger than that of the nonsmokers; also, the numbers of CD4+ and CD3+ T lymphocytes in smokers of each group of AA-production and AA-use workers were significantly larger than those in nonsmokers. Number of CD4+ and CD3+ T lymphocytes in nonsmokers of AA-production and CR workers were significantly smaller than those in nonsmokers of nonexposed workers; the number of CD8+ T lymphocytes in nonsmokers of CR workers was significantly smaller than that in nonsmokers of nonexposed workers. The cross-sectional study suggests that (1) smoking increases CD4+ (and CD3+) T lymphocytes in all categories of workers except for CR workers; (2) exposure to CRs and AAs decreases CD4+ (and CD3+) T lymphocytes; (3) the magnitude of decrease in CD4+ T lymphocytes is large among CR workers, intermediate among AA-production workers, and small among AA-use workers regardless of smoking status; and (4) exposure to CRs also decreases CD8+ T lymphocytes.

Adult↗
PubMed1998

Pyrrolidone carboxyl peptidase from the hyperthermophilic Archaeon Pyrococcus furiosus: cloning and overexpression in Escherichia coli of the gene, and its application to protein sequence analysis.

A gene for a pyrrolidone carboxyl peptidase (Pcp: EC 3.4.19.3, pyroglutamyl peptidase), which removes amino-terminal pyroglutamyl residues from peptides and proteins, has been cloned from the hyperthermophilic Archaeon Pyrococcus furiosus using its cosmid protein library, sequenced, and expressed in Escherichia coli. The DNA sequence encodes a protein containing 208 amino acid residues with methionine at the N-terminus. Analysis of the recombinant protein expressed in E. coli, including amino acid sequence analysis from the N-terminus by automated Edman degradation and ionspray mass spectrometric analysis of the peptides generated by enzymatic digestions with lysylendopeptidase and Staphylococcus aureus V8 protease, showed its primary structure to be completely identical with that deduced from its cDNA sequence. Comparison of the amino acid sequence of P. furiosus Pcp (P.f.Pcp) with those of bacterial Pcps revealed that a high degree of sequence identity (more than 40%) and conservation of the amino acid residues comprising the catalytic triad, Cys142, His166, and Glu79. On the other hand, a unique short stretch sequence (positions around 175-185) that is absent in bacterial Pcps was found in P.f.Pcp. A similar stretch has also been reported recently in the amino acid sequence of Pcp from the hyperthermophilic Archaeon Thermococcus litoralis [Littlechild et al., in abstracts of the "International Congress on Exthermophiles '98" p. 58 (1998)]. To elucidate their contribution to the hyperthermostability of these enzymes, further structural studies are required.

Amino Acid Sequence↗
PubMed1998

Polylysine-induced rapid Ca2+ release from cardiac sarcoplasmic reticulum.

The rapid kinetics of polylysine-induced Ca2+ release from cardiac sarcoplasmic reticulum (SR) was assessed in combination with its effect on ryanodine binding. SR vesicles were isolated from canine cardiac SR. The time course of SR Ca2+ release was continuously monitored by a stopped-flow apparatus, and [3H]ryanodine binding was done by using the filtration method. The initial rate of polylysine-induced Ca2+ release from cardiac SR revealed different concentration dependence from those observed in skeletal SR. The initial rate peaked at 0.11 microM, followed by a decrease at higher concentrations in skeletal SR, whereas it increased to 3.7 microM in cardiac SR. The [3H]ryanodine binding was also stimulated by polylysine with an identical parallelism with Ca2+ release in terms of polylysine concentration dependence. Thus we demonstrated that the cardiac SR Ca2+ release channel is sensitive to activation by polylysine and that there is a difference in the concentration dependence of polylysine-induced activation of cardiac and skeletal SR Ca2+ release channels.

Animals↗
PubMed1998

Effects of balanced vasodilator, flosequinan, on aortic impedance in failing heart.

An arteriovenous vasodilator, flosequinan, has been shown to be effective for the treatment of acute heart failure. However, little is known as to its effect on aortic impedance, which is known to be a proper and precise expression of left ventricular (LV) afterload. To evaluate the acute cardiovascular effect of flosequinan in failing heart, we administered flosequinan intravenously to seven dogs with cardiac failure produced by an infusion of carbon powder (20-50 microm in diameter) into left main trunks of coronary artery. The LV-pump function was severely impaired after intracoronary injection of carbon powder, as evidenced by the findings that cardiac output, circumferential shortening velocity (mean Vcf), and peak +dP/dt of LV pressure were all decreased, associated with a significant increase in LV end-diastolic pressure. Flosequinan (0.9 mg/kg, i.v.) increased cardiac output by 28%, mean Vcf by 44%, and peak +dP/dt by 24%, whereas it decreased total systemic resistance by 32%, time constant of LV pressure decay by 22%, and LV end-diastolic pressure by 18%. Moreover, flosequinan substantially decreased the pulsatile components of LV afterload (i.e., characteristic impedance by 11% and arterial wave reflection coefficient by 45%). Thus flosequinan exerted not only positive inotropic but also positive lusitropic effects, in association with a significant reduction of both pulsatile and steady components of LV afterload, contributing to an improvement of LV-pump function in acute cardiac failure.

Animals↗
PubMed1998

Scanning electron microscopic and cytochemical analyses of alveolar and peritoneal macrophages of mice, dogs and cats.

Alveolar and peritoneal macrophages (MPs) of mouse, dog and cat were compared in relation to their scanning electron microscopic features and the lysosomal activities of nonspecific esterase, acid phosphatase, and beta-glucuronidase. The long spindle shape of peritoneal MPs differed from the spherical form of alveolar MPs in all species. There was no difference in the morphological findings among the three animals. Murine alveolar and peritoneal MPs were strongly positive for all three enzymes. Canine and feline alveolar and peritoneal MPs were strongly positive for acid phosphatase and beta-glucuronidase, but weakly positive for nonspecific esterase. These results strongly suggest that acid phosphatase and beta-glucuronidase can be used as markers of the MPs in healthy dogs and cats.

Acid Phosphatase↗
PubMed1998

Assessment of mutations of Ha- and Ki-ras oncogenes and the p53 suppressor gene in seven malignant mesothelioma patients exposed to asbestos--PCR-SSCP and sequencing analyses of paraffin-embedded primary tumors.

To examine whether malignant mesothelioma due to asbestos has genetic alterations in the Ha- and Ki-ras oncogenes or in the p53 suppressor gene, we analyzed the point mutations of these genes in paraffin-embedded autopsy samples of the primary tumors of malignant mesothelioma in seven asbestos patients who died from malignant mesothelioma. The genetic analysis was conducted by the polymerase chain reaction-single strand comformation polymorphysms (PCR-SSCP) method in all patients, and through the sequencing of deoxyribonucleic acid (DNA) bases in one patient. No genetic alterations were found in exons 1 or 2 of Ha- and Ki-ras oncogenes, or in exons 5 to 9 of the p53 gene, in any of the patients. Further studies on a larger number of patients are required to reach a definite conclusion concerning the genetic effects of asbestos on malignant mesothelioma.

Aged↗
PubMed1998

Increase in the helper inducer (CD4+CD29+) T lymphocytes in smokers.

Previously, we reported an increase in the number of CD4+ T lymphocytes in the peripheral blood of smokers. In the present study, subpopulations of CD4+ T lymphocytes together with CD8+ T lymphocytes, total (CD3+) T lymphocytes, B (CD19+) lymphocytes, natural killer (CD16+) cells and total lymphocytes were examined by two-color staining using anti-2H4 (CD45RA) and anti-4B4 (CD29) monoclonal antibodies in 8 male smokers and 22 age-matched male non-smokers. The number of CD4+CD29+ T lymphocytes in smokers was significantly higher than that in non-smokers. The total number of CD4+ T lymphocytes in smokers was also significantly higher. No significant differences in CD8+ T, CD19+ B lymphocytes and CD16+ NK cells were found between smokers and non-smokers. Thus, it is suggested that the increase in the number of CD4+CD29+ (helper inducer) T lymphocytes is responsible for the increase in total CD4+ T lymphocytes in smokers.

Adult↗
PubMed1998

[The relation between platelet aggregation and constitutional and lifestyle variables in two Japanese communities].

To investigate the contribution of the platelet aggregation in the development of cardiovascular diseases, we examined the relation of constitutional and lifestyle variables with platelet aggregation for a total of 306 males aged 50 to 70 in Ikawa town, Akita prefecture (n = 163) and Noichi town, Kochi prefecture (n = 143). The examination of platelet aggregation was completed within 3 hours of obtaining blood samples. We used ADP (Adenosine 5'-diphosphate) as an agonist and obtained PATI (the platelet aggregatory threshold index) by nephelometry. Platelet count, mean platelet volume, white blood cell count, serum fatty acid compositions were also examined and dietary intake of fish, seafood and soy bean foods were inquired using one-week dietary records. PATI indicated a logarithmic normal distribution in both Ikawa and Noichi. The mean of logarithmic transformed PATI (log PATI) was higher in Ikawa than in Noichi. Thus platelet aggregation was lower in Ikawa than in Noichi. According to multiple regression analysis, age, platelet count in platelet rich plasma, mean platelet volume in platelet rich plasma, and white blood cell count were inversely associated with log PATI. Serum arachidonic acid composition tended to be inversely related with log PATI. Serum n3-polyunsaturated fatty acid composition was positively related with log PATI, and log gamma-GTP tended to be positively associated with log PATI. Soy protein intake and cigarette smoking showed no consistent associations with log PATI. This cross-sectional study suggests that serum n3-polyunsaturated fatty acid, and gamma-GTP, as an index of alcohol intake, reduce platelet aggregation while age, white blood cell count, platelet count, mean platelet volume, and serum arachidonic acid raise platelet aggregation.

Age Factors↗
PubMed1998

[Survival and disability in stroke by stroke subtype based on computed tomographic findings in three rural Japanese communities].

PURPOSE: We conducted an epidemiological study of survival and disability in stroke in three Japanese communities to seek community strategies for improvement in survival and disability. METHODS: A total of 297 first-ever strokes were identified between 1988 and 1992 in three rural communities (total population = 47,000) located in Akita and Ibaraki. We analyzed survival rates and activity of daily living by sex, age-group and stroke subtypes. Successful review of computed tomography (CT) for 84 percent of the strokes (249 out of 297) was possible and the data were used for subtype analyses. RESULTS: For all strokes (n = 297) survival rates were 85% for 30 day, 70% for one year, 62% for three year. The rates tended to be lower in women than in men. The rates were lowest in ages less than 60 at thirty day, and in ages 80 and older at the end of the first and third year. Intracerebral hemorrhage with ventricular rupture, subarachnoid hemorrhage and cortical cerebral infarction had lower survival rates than intracerebral hemorrhage without ventricular rupture and lacunar infarction. Based on Cox's proportional hazard model, risk ratio for death was 2.07 in ages 70-79, and 3.80 in ages 80 and older compared with ages 60-69. The risk ratio was 3.46 for intracerebral hemorrhage with ventricular rupture, 3.38 for subarachnoid hemorrhage and 2.46 for cortical cerebral infarction compared with lacunar infarction. The proportion of stroke survivors who need assistance from others in the first and third years tended to be higher in women than in men. The proportion was higher in older patients than in the younger, and higher for intracerebral hemorrhage with ventricular rupture and cortical cerebral infarction than in other subtypes of stroke. From logistic regression analysis, the odds ratio for disability in the first year was 6.55 for ages 80 and older compared with ages 60-69. The odds ratio was 5.61 for intracerebral hemorrhage with ventricular rupture, 4.53 for cortical cerebral infarction compared with lacunar infarction. In the third year the odds ratio was significant for ages 70-79, and decreased for intracerebral hemorrhage with ventricular rupture (odds ratio = 2.98), and increased for cortical cerebral infarction (odds ratio = 6.06). CONCLUSIONS: Survival and disability in stroke depended on age and stroke subtypes. Even after age adjustment, stroke subtypes with large cerebral involvement had worse prognosis than stroke subtypes. Community-based hypertension control programs are important to prevent any subtypes of stroke. Stroke subtypes as well as age should be taken into account to develop effective care and medical treatments for strokes.

Activities of Daily Living↗
PubMed1998

[High shear stress induced platelet aggregation (h-SIPA) and effects of antiplatelet therapy].

A physiologic time averaged mean shear stress in stenosed coronary artery reach more than 350 dyne/cm2. Pathologic stenosis can directly lead to shear-induced aggregation of platelets. Platelet aggregation in response to pathologically elevated shear stress is depend on the presence of plasma von Willebrand factor (vWF) and platelet receptor glycoprotein (GP) Ib/IX and GPIIb/IIIa. Fibrinogen bridging thrombus play as key factor at low shear rate, however, vWF is most important factor at high shear rate. When high shear stress are applied to vWF, vWF change the shape round to linear, and bind to extracellular matrix such as collagen type I or III exposed to blood by rupture of atheromatous plaque. Consequently vWF interact with GP Ib/IX for initial adhesion without agonist stimulation, which is followed by activation of GPIIb/IIIa receptor and co-binding with GPIIb/IIIa and vWF. The binding of platelets via vWF is strengthen to sustain the opposing effect of high shear forces in coronary artery. In our study, significant increases of h-SIPA and plasma vWF levels were observed in patients with acute coronary syndrome compared with patients with chronic coronary artery disease. The additional application of ticlopidine or cilostazol to aspirin therapy significantly inhibition of h-SIPA in patient with acute coronary syndrome, however, less effective than patients with chronic coronary artery disease.

Acute Disease↗
PubMed1997

Establishment and characteristics of a practical and useful astrocyte cell line transformed by a temperature-sensitive mutant of simian virus 40.

A practical mouse astrocyte cell line (A640-IG) was established by transformation with a temperature-sensitive mutant of simian virus 40 (SV40) and the relationship between the function of SV40 large T antigen and the growth and differentiation of A640-IG cells, which are most clearly dependent on temperature that ever established, was reported. A640-IG cells proliferated actively with expression of large T antigen when they were cultured at 33 degrees C. They had a fibroblast-like appearance, and displayed faint immunoreactivity with an antibody against glial fibrillary acidic protein (GFAP). However, when large T antigen expression ceased at 39 degrees C, the cells did not grow actively and differentiated into astrocytes as demonstrated by both their morphological and immunohistochemical characteristics. Differentiation into astrocytes was more obvious when the cells were plated on bacteriological dishes in high density. Western blotting confirmed immunohistochemical observations. A640-IG cells thus showed contrasting behaviour in terms of cell growth and differentiation depending on the temperature. This unique and practical astrocyte cell line is a useful model for investigating the mechanisms of astrocyte growth and differentiation.

Animals↗
PubMed1997

Nuclear accumulation of HMG2 protein is mediated by basic regions interspaced with a long DNA-binding sequence, and retention within the nucleus requires the acidic carboxyl terminus.

High mobility group 2 (HMG2) protein is ubiquitously distributed in the nucleus of higher eukaryotic cells. Accumulation of an HMG2-beta-galactosidase fusion protein expressed in COS-7 cells suggested active transport of HMG2 protein into the nucleus after translation in the cytoplasm. Deletion analysis of the HMG2 sequence in the HMG2-beta-galactosidase fusion protein indicated that basic regions interspaced with the long DNA-binding sequence in HMG2, called the HMG1/2 box, are necessary for the nuclear accumulation of HMG2. The close configuration of basic regions at both ends of the DNA-binding sequence in the tertiary structure may function as the nuclear localization signal. This novel nuclear localization signal structure is different from typical ones such as the single or bipartite basic cluster in many nuclear proteins. A portion of the HMG2 molecule remained in the cytoplasm after translation. Interspecies heterokaryon assay demonstrated that the acidic carboxyl terminus of HMG2 was necessary for retention of the protein in the nucleus.

Animals↗