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Biomedical subjects

T Tanigawa

Publications and source records attributed to T Tanigawa.

At least 163 records · Page 9Linked to original sources

Natural killer cell activity in workers exposed to benzidine and beta-naphthylamine.

To investigate the effects of benzidine (BZ) and beta-naphthylamine (BNA) on the immune system in man, the activity of natural killer (NK) cells as well as the relative number (percentage) of Leu 11a positive cells in peripheral blood lymphocytes were measured in 63 dyestuff workers exposed to BZ and BNA (aromatic amines, AA). The cytotoxic potential per NK cell (unit NK cell activity) was approximated by dividing the NK activity per fixed numbers of unseparated mononuclear cells by the percentage of Leu 11a positive lymphocytes that mediated NK activity. Thirty one of these workers had previously been treated for bladder cancer and then cured (ex-cancer AA workers) whereas the remaining 32 had not been diagnosed as having bladder cancer (non-cancer AA workers). There was no significant difference in the gross NK activity per unseparated peripheral mononuclear cells among ex-cancer AA workers, non-cancer AA workers, and the control group (p greater than 0.05). The relative number of Leu 11a positive cells, on the other hand, was significantly higher in AA workers than in the control group (p less than 0.01). The unit NK cell activity, as a result, was significantly more reduced in both ex-cancer and non-cancer AA workers than in the control group (p less than 0.05 and p less than 0.01, respectively). Between ex-cancer and non-cancer AA workers, no significant difference was observed in terms of unit NK cell activity. These results indicated that the function of NK cells per se was impaired in AA workers whereas the number of circulating NK cells was relatively increased.

2-Naphthylamine↗

Membrane fluidity and lipid composition of rat testicles in experimental cryptorchidism.

Membrane fluidity and lipid composition of rat testis in experimental bilateral cryptorchidism were studied. Membrane fluidity measured by fluorescence anisotropy of diphenylhexatriene decreased on the 3rd day of intraabdominal fixation, at an early stage of cryptorchidism. Lipid composition of testicular membrane was changed drastically by the treatment, and time-dependent changes were observed during the course of the experiment. Cholesterol content increased significantly, but phospholipid content was not affected by the treatment. The ratio of cholesterol to phospholipids increased significantly. Fatty acid moieties of phospholipids varied during the course of the experiment. The ratio of unsaturated to saturated fatty acids decreased on the 3rd day. These changes indicated a different physical state of cryptorchid membranes from normals, and the changes may be involved in the pathophysiology of cryptorchidism.

Animals↗

Fibronectin on prosthetic denture fabrication.

It is well known that fibronectin adheres to various oral bacteria and shows affinity to various components. Thus the existence fibronectin which is present in the salivary flow, acquired pellicle and dental plaque, was investigated in used acrylic resin dentures with a direct immunohistochemical fluorescent technique using antihuman fibronectin goat serum which was labeled with fluorescein isothiocyanate (FITC). It was found that fibronectin frequently was present on the surface of acrylic resin dentures.

Acrylic Resins↗

p24 protein of a human T-lymphotropic virus type-I (HTLV-I) producing cell line (TCL-Kan) reacts with some normal pregnant women's sera.

Some HTLV-1 antibody carrying pregnant women, who are rated by the gelatin particle agglutination (PA) method, show no expression of HTLV-I antigen in their peripheral blood lymphocytes. Paying attention to this fact, the authors recently studied the reaction of the antibody contained in the PA-positive sera with the antigen protein used for the PA method. This study demonstrated that the protein responsible for non-specific reaction has a molecular weight of 24,000 and that the isoelectric point of this protein differs from that of HTLV-I specific protein.

Agglutination Tests↗

[Role of active oxygen species and lipid peroxidation in liver injury induced by ischemia-reperfusion].

The role of superoxide and lipid peroxidation in liver injury induced by ischemia-reperfusion was investigated in rats. Ischemic condition of the liver was created by applying small clamps to the right branch of portal vein and the right hepatic artery for 15 min. Clamping of hepatic artery and portal vein could decrease the hepatic blood flow to about 30% of that measured before the clamping. Levels of serum GPT and thiobarbituric acid (TBA) reactive substances in the liver tissue were significantly increased 30 min after the reperfusion following 15 min of ischemia. The increase in serum GPT and TBA reactants in the liver tissue was significantly inhibited by the treatment with superoxide dismutase combined with catalase. The treatment with allopurinol significantly inhibited the elevation of serum GPT levels and showed a tendency to inhibit the increase in TBA reactants in liver tissue. These results suggest that active oxygen species and lipid peroxidation may play an important role in the pathogenesis of ischemia-reperfusion injury in the liver, and hypoxanthine-xanthine oxidase system may be one of the main sources of active oxygen species.

Animals↗

[Role of free radicals and lipid peroxidation in gastric mucosal injury induced by ischemia-reperfusion in rats].

Ischemia and reperfusion is of the greatest importance in the pathology of various diseases. This study was designed to investigate the role of oxygen-derived free radicals and lipid peroxidation in gastric mucosal injury induced by ischemia-reperfusion in rats. Clamping of the celiac artery in rats reduced the gastric mucosal blood flow to 10% of that measured before the clamping. Gastric mucosal injury, such as spotty and linear hemorrhagic erosions, was seen in rats 60 min of the reperfusion following 30 min of ischemia. Thiobarbituric acid (TBA) reactants in the gastric mucosa were increased after the reperfusion. The increase in gastric mucosal lesions and TBA reactants were significantly inhibited by the treatment with SOD+ catalase and allopurinol. These results suggest that oxygen-derived free radicals and lipid peroxidation may play an important role in the pathogenesis of acute gastric mucosal lesions induced by ischemia-reperfusion.

Animals↗

[Detection of HTLV-I genome in infants born to HTLV-I seropositive mothers by polymerase chain reaction].

We developed a new method to detect human T cell leukemia virus type I (HTLV-I) provirus by amplifying the pX region of the HTLV-I genome by means of the polymerase chain reaction (PCR) method. This new method was used to examine babies delivered by HTLV-I carrier women for HTLV-I vertical transmission. It was found that intra-uterine infection with HTLV-I can occur, though rarely, and some babies carry HTLV-I provirus despite their negative response to HTLV-I antibody, and, noticeably, some of the babies found negative by the conventional antigen detection method may be positive when tested by the PCR method. It was also confirmed with the PCR method that the incidence of vertical transmission of HTLV-I can be reduced to about 1/5 by replacing breast feeding with bottle feeding and frozen mother's milk feeding. It was also found that vertical transmission of HTLV-I can occur at high incidence rates even when the duration of breast feeding is 3 months or less.

Breast Feeding↗

Bottle-feeding can prevent transmission of HTLV-I from mothers to their babies.

Breast-feeding is a major factor in the vertical transmission of human T-lymphotropic virus type I (HTLV-I). We studied whether such transmission may be prevented by bottle-feeding. HTLV-I infection was detected by both HTLV-I antigen and antibody tests. Thirty bottle-fed babies were examined 24 months after birth; only one was found to be HTLV-I antigen-positive. This infection rate was lower than that for breast-fed babies in whom HTLV-I antigen was detected in 24 of the 31 24-month-old babies born to HTLV-I positive mothers in a previous study. These results suggest that most vertical transmission of HTLV-I is attributable to breast-feeding and can be prevented by bottle-feeding.

Bottle Feeding↗

Detection of HTLV-I genome in seronegative infants born to HTLV-I seropositive mothers by polymerase chain reaction.

We applied the polymerase chain reaction (PCR) method to detect gag, env and pX sequences of human T cell leukemia virus type I (HTLV-I) provirus in peripheral blood lymphocytes of seronegative infants born to HTLV-I seropositive mothers. Out of 22, five subjects were found to contain the HTLV-I provirus genome. Two of the five cases were judged to be negative for not only anti-HTLV-I antibodies but also the viral antigens on cultivated lymphocytes by the conventional antibody/antigen detection methods. These results indicate that PCR is of great use as a simple and highly sensitive method detect HTLV-I infection.

Adult↗

Effect of freeze-thawing breast milk on vertical HTLV-I transmission from seropositive mothers to children.

Breast feeding is known to be a major cause of vertical transmission of HTLV-I from mothers to her children. The infectiousness of HTLV-I in breast milk was reported to be lost during freezing and thawing processes. We therefore administered frozen-and-thawed breast milk of HTLV-I carriers to their babies. Among the 13 babies given the frozen-and-thawed breast milk (now 12 months of age), no infection has been found yet. This result suggests that freezing and thawing of breast milk is a promising method for the prevention of vertical HTLV-I infection to breast-fed babies.

Breast Feeding↗

Role of free radicals and lipid peroxidation in gastric mucosal injury induced by ischemia-reperfusion in rats.

Ischemia and reperfusion are of the greatest importance in the pathology of many diseases. We investigated the roles of oxygen-derived free radicals and lipid peroxidation in gastric mucosal injury, such as spotty and linear hemorrhagic erosions, induced in rats by ischemia-reperfusion. The gastric mucosal injury and the increase in thiobarbituric acid (TBA) reactants in the gastric mucosa induced by ischemia-reperfusion were significantly inhibited by treatment with SOD and catalase. These results suggest that oxygen-derived free radicals and lipid peroxidation play important roles in the pathogenesis of acute gastric mucosal lesions induced by ischemia-reperfusion.

Animals↗

Pathogenesis of platelet-activating factor-induced gastric mucosal damage in rats.

Platelet-activating factor (PAF), given intravenously, induced erosions and hyperemia to the rats stomachs. Gastric mucosal blood flow was decreased and thiobarbituric acid (TBA) reactants (an index of lipid peroxidation) in the gastric mucosa were increased 10 min after PAF injection. Superoxide dismutase plus catalase reduced the gastric mucosal lesions and TBA reactants, but had no influence on gastric mucosal blood flow. A reduction in the number of circulating polymorphonuclear leukocytes (PMN) reduced the gastric mucosal damage and TBA reactants, and inhibited the decrease in gastric mucosal blood flow, as observed 30 and 60 min after PAF injection. PAF induced superoxide production by rat PMN and enhanced that stimulated by opsonized zymosan or phorbol myristate acetate. These results suggest that microcirculatory disturbance and oxygen-derived free radicals generated by PMN play important roles in gastric mucosal lesions induced by PAF.

Animals↗

[Acoustic investigation of various palatal rugae].

We use some palatal plates with some Kinds of palatal rugae; ready made, patterned, individually copied and omitted, and studied the influence of the pronunciation acoustically concerning the Formant Frequency.

Dental Impression Technique↗

[Influences of anti-allergic drugs on superoxide generation from the hypoxanthine-xanthine oxidase system or polymorphonuclear leukocytes].

The influences of anti-allergic drugs on superoxide generation from the hypoxanthine-xanthine oxidase system or polymorphonuclear leukocytes (PMN) were studied by an electron spin resonance assay using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trapper. The intensity of DMPO-OOH signal generated from the hypoxanthine-xanthine oxidase system was not influenced by the presence of azelastine, ketotifen, disodium cromoglycate, mequitazine, or methylprednisolone, but it decreased in the presence of AA-673. A kinetic study showed that the second order rate constant for reaction between AA-673 and superoxide anion at pH 7.4 was 2.9 x 10(8)M-1S-1. The relative intensity of DMPO-OOH spin adduct generated from PMN stimulated with phorbol myristate acetate (PMA) or opsonized zymosan (OZ) significantly decreased in the presence of azelastine: from the PMN-PMA system, with 10.7 microM concentration of molar concentration causing 50% reduction of the signal intensity (IC50), while from the PMN-OZ system, with 10.5 microM concentration of IC50, and also decreased in the presence of mequitazine: from the PMN-PMA system, with 10.8 microM concentration of IC50, while from the PMN-OZ system, less than 2.0 microM concentration of IC50. These results suggest that some anti-allergic drugs may have anti-inflammatory and anti-oxidative actions due to scavenging superoxide radicals or due to inhibiting superoxide production.

Aminopyridines↗

An acoustic investigation caused by pontic formation.

Prosthetics for cases with large defects of alveolar bone often tend to be difficult. We researched the acoustic effects of various pontic forms to satisfy a patient's expectations for both phonetics and aesthetics.

Alveolar Process↗

[Role of lipid peroxidation and polymorphonuclear leukocytes-derived oxygen radicals in acute gastric lesions induced by hyperthermic treatment].

Acute gastric lesions were experimentally induced by local hyperthermic treatment (42 degrees C, 40 min). Thiobarbituric acid (TBA) reactants in the gastric mucosa were significantly increased 40 min after the hyperthermia. There were no changes in gastric mucosal blood flow and gastric acid secretion. The total area of gastric erosions and TBA reactant in gastric mucosa of rats deficient in vitamin E were significantly increased compared with those of rats supplemented with vitamin E. The increase in the total area of gastric erosions and TBA reactants in gastric mucosa were significantly inhibited by the treatment of bovine Cu, Zn-SOD and bovine catalase, and by the depletion of polymorphonuclear leukocytes (PMN). Allopurinol did not show any influence on these pathological changes induced by hyperthermia. These results suggest that lipid peroxidation and PMN-derived oxygen radicals may play an important role in the pathogenesis of gastric lesions induced by hyperthermic treatment.

Acute Disease↗