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Biomedical subjects

M Itoh

Publications and source records attributed to M Itoh.

At least 1,009 records · Page 56Linked to original sources
PubMed1987

Contribution of the complement system to antibody-mediated binding of Trypanosoma gambiense to macrophages.

The role of complement in the process of binding of trypanosomes to macrophages in the presence of specific antibody was studied. The aggregation of trypanosomes observed at the optimal antigen-antibody ratio or in the presence of excess antigen inhibited the binding. Complement caused clumped trypanosomes to dissociate, and the free trypanosomes, which were presumed to be coated with antibody that had fixed complement, readily attached to surfaces of phagocytes. Thus, complement was shown to contribute at the site of the antigen-antibody reaction to the creation of an environment suitable for the binding. It seems likely that the trypanosomes dissociated by complement adhered to C3 receptors of the macrophage. However, in the absence of complement and in regions of antibody excess, free trypanosomes also attached to phagocytes. Thus phagocytes may also have receptors for the Fc portion of aggregated antibody. Complement activated by the alternate pathway also enhanced attachment of trypanosomes to phagocytes, but the effect was not as rapid as it was when complement was activated by classical means.

Animals↗
PubMed1987

[Intraoperative liquid embolization of an arteriovenous malformation in the basal ganglia and thalamic region].

Total three patients with arteriovenous malformation (AVM) in basal ganglia or thalamic region were treated by intraoperative liquid embolizations. These procedures were decided because of repeated hemorrhagic episodes. In the case with AVM in the head of the caudate nucleus which was fed by several anterior perforating arteries originated from anterior cerebral artery (A1 portion) and middle cerebral artery (M1 portion), frontotemporal craniotomy was performed. After the microsurgical dissection of these feeders, one of the feeders lenticulostriate artery, was cannulated with a small-caliber polyethylene catheter, 0.6 mm in outer diameter and 0.3 mm in inner diameter. A small amount of isobutyl 2-cyanoacrylate (IBCA) was injected through the catheter. Same procedure was carried out one month later. Postoperative angiograms revealed about 90% loss of AVM. In two cases with AVM which involved almost entire thalamus, subtemporal craniotomy was done. Feeding vessels which originated from posterior communicating artery and posterior cerebral artery (PCA) were carefully dissected under the operative microscope and one of them was prepared for cannulation with small catheter. When the small amount of IBCA was injected, proximal PCA and internal carotid artery were temporarily occluded. In both cases intraoperative embolization was carried out twice. Postoperative angiograms revealed that the size of AVM was decreased to 20% in one and 40% in the other. Although temporary postoperative deterioration of neurological deficits such as hemiparesis and visual disturbance was slightly noted in all cases, no hemorrhagic episode was experienced for 6 months, 1.5 and 2 years in each after embolization.

Adult↗
PubMed1986

Comparative efficacy of high-dose versus low-dose nicorandil therapy for chronic stable angina pectoris.

Nicorandil therapy was compared with placebo therapy in 11 patients with chronic stable angina pectoris. A computer-assisted treadmill exercise test was performed after administration of either 10 or 30 mg of nicorandil. Analysis of variance showed a significant difference among placebo and nicorandil treatments (p less than 0.01). Ten milligrams of nicorandil prolonged time to onset of ischemia 36% (p less than 0.05) but increased the exercise duration only 15%. Thirty milligrams of nicorandil prolonged time to onset of ischemia 82% (p less than 0.01) and exercise duration 45% (p less than 0.01). Both time to onset of ischemia and exercise duration increased progressively from the 10-mg to the 30-mg dose (p less than 0.05). Heart rate at rest was significantly higher and systolic pressure at rest significantly lower with 30 mg of nicorandil than with placebo. After administration of 30 mg of nicorandil there was a significant reduction in ST depression associated with a slight decrease in the double product at the end of Bruce stage 2 exercise. The peak double product was greater after administration of 30 mg of nicorandil than after placebo, indicating an increased myocardial oxygen supply to the ischemic area. The plasma concentration of nicorandil averaged 78 +/- 83 ng/ml with the 10 mg and 313 +/- 142 ng/ml with 30 mg. There was an increase in exercise duration of more than 1 minute in 8 of 9 patients who had plasma nicorandil concentrations greater than 100 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Physiological concentrations of human epidermal growth factor in biological fluids: use of a sensitive enzyme immunoassay.

A sandwich enzyme immunoassay for epidermal growth factor (EGF) has been developed which measures EGF concentrations in serum, urine, saliva, gastric and pancreatic juices without pretreatment. Sensitivity for human EGF is 500 fg/tube. Serum EGF concentration in normal males and females is 780 and 604 pg/ml, respectively. Urinary human EGF is 51.3 ng/mg creatinine for males, and 68.3 ng/mg creatinine for females. The difference is not significant, and no correlation between serum and urinary concentrations exists, but serum concentration changes with age. The highest concentration is seen up to 9 years of age, suggesting that EGF promotes cell proliferation during growth.

Adolescent↗
PubMed1986

Enhancement of the expression of a rat neutrophil-specific cell surface antigen by activation with phorbol myristate acetate and concanavalin A.

A monoclonal antibody against rat neutrophils, RP-1, was produced by hybridizing a mouse myeloma (P3-X63-Ag8.653) with BALB/c mouse spleen cells sensitized with peritoneal neutrophils from Wistar-King-Aptakeman/Hok rats. RP-1 specifically reacted to neutrophils and bone marrow cells from rats of various strains. The expression of an antigen reactive to RP-1 on rat peritoneal neutrophils was enhanced by stimulation with phorbol myristate acetate and concanavalin A. The experimental result that the expression of an antigen reactive with another anti-neutrophil monoclonal antibody was not enhanced by stimulation with phorbol myristate acetate indicates that the antibody-binding capacity of stimulated neutrophils was not nonspecifically enhanced. The enhancement of antigen expression was temperature dependent. A glycolytic inhibitor, 2-deoxy-D-glucose, and an inhibitor of intracellular calcium mobilization, 3,4,5-trimethoxybenzoic acid 8-(diethylamino)-octyl ester hydrochloride, which inhibited hydrogen peroxide release from stimulated neutrophils, did not inhibit enhancement of the expression of an antigen reactive with RP-1.

Animals↗
PubMed1986

Assessment of radiotherapeutic effects on experimental tumors using 18F-2-fluoro-2-deoxy-D-glucose.

The purpose of this study is to evaluate the effect of tumor volume and radiotherapy on the uptake of 18F-2-fluoro-2-deoxy-D-glucose (18FDG). The tumor models used were mouse mammary carcinoma MM48, FM3A, and rat hepatoma AH109A. Results were expressed as an 18FDG uptake ratio. This was the ratio of irradiated tumor uptake of 18FDG to unirradiated tumor uptake. The total tumor uptake was expressed as 18FDG uptake ratio multiplied by relative tumor volume. Following 20 Gy irradiation of the radioresistant tumor (MM48), the 18FDG uptake ratio was found to be unchanged, whereas in radiosensitive tumors (FM3A) the 18FDG uptake ratio was 0.37, the relative tumor volume was 0.31, and the calculated total tumor uptake was 0.11 on the eighth day after irradiation. The total tumor uptake was lower than the relative tumor volume. AH109A began to regrow after ten Gy irradiation, accompanied by elevated uptake of 18FDG on the seventh day. These results suggest that the 18FDG uptake by tumor is a good marker of radiotherapeutic effects as well as relapses of cancers and is more sensitive than morphological methods.

Animals↗
PubMed1986

Peroxidase activity in rat tracheal epithelium and gland.

Endogenous peroxidase activity in the upper tracheal epithelium and submucosal gland of specific pathogen-free rats was examined cytochemically using the DAB method in animals bred in a conventional room without special equipment for air filtration (conventional system), and those bred under a semibarriered system in which fresh air was filtered and controlled to flow in one way (semibarriered system). Peroxidase activity was consistently positive in the serous cells of the gland of all the rats in both groups. In 22 (71.0%) of the 31 rats in the conventional system, peroxidase activity was demonstrated also in ciliated cells, mucous cells, and goblet cells of the tracheal epithelium, and in mucous cells and duct cells of the tracheal submucosal gland. However, the activity was detected in these cells only in 2 (6.7%) of the 30 rats in the semibarriered system. Goblet cells were not observed in the latter group of rats. The fine localization of peroxidase activity was similar among the peroxidase positive cells, and was demonstrated in the cisternae of the nuclear envelope and rough-surfaced endoplasmic reticulum, some parts of Golgi apparatus, secretory granules, and in some cases in the intraductal spaces of the gland. The present study indicated that environmental conditions markedly influence peroxidase activity in the upper tracheal epithelium and gland of rats.

Air Conditioning↗
PubMed1986

Hemorrhagic shock and acid gastric injury in the rat. Comparison of gross and histologic findings.

The purpose of this study was to compare the gross and histologic changes in the corpus and antrum in the rat hemorrhagic shock plus acid model of gastric injury, and to determine the effect of transfusion of shed blood or albumin on gastric lesion formation. The data indicate that (a) despite the gross appearance of more severe damage in the corpus, histologic damage was more severe in the antrum; (b) covering mucus and cell debris partly explain the difficulty in recognizing antral lesions grossly; (c) the severity of histologic injury was similar in transfused and nontransfused rats; and (d) transfusion of shed blood rendered corpus lesions more recognizable grossly but did not affect the severity of histologic injury. The latter findings raise questions about the pathogenetic importance of reperfusion in gastric ischemic injury and the validity of using gross lesions as an index of gastric injury.

Albumins↗
PubMed1986

Voice onset time perception in Japanese aphasic patients.

This study examines identification of the synthetic speech stimuli [ga] and [ka] of varying voice onset times (VOTs) in 17 Japanese aphasic subjects. Approximately two-thirds of the aphasic subjects showed deterioration in performance of VOT identification of the stimuli. A quantitative analysis of the results indicates that the problems of the majority of these subjects may be attributable not only to difficulty in labeling the stimuli but also to difficulty in processing the acoustic and/or phonetic information of the stimuli.

Adult↗
PubMed1986

Gain of slow-phase velocity of optokinetic nystagmus.

Although slow-phase velocity of optokinetic nystagmus (OKN) increases according to the increase of stimulus velocity, it is not obvious whether both are quite equal or not. In this study, gain of slow-phase velocity in OKN response to stimulation velocity was analyzed by two methods of stimulation, constant acceleration, and constant velocity stimulation. In our observation, the gain of slow-phase velocity was not equal to 1.0 even at low-speed stimulation. On the other hand, the number of nystagmus almost corresponded to the number of stimulation stripes passing through the center of an OK-drum up to high-speed stimulation. The results of this study indicate that pursuit eye movement of slow-phase OKN should not be quite equal to that of the eye tracking test, i.e. being required to continuously look at a moving spot.

Acceleration↗
PubMed1986

Survey of 200 cases of sporotrichosis.

A survey of 200 cases of sporotrichosis seen at the Dermatology Clinic of Chiba University Hospital from May 1965 to August 1983 is reported. The proportion of cases with sporotrichosis to the total number of outpatients was 0.15%. A higher percentage of cases fell into the less than 12-year-old or more than 40-year-old age groups. The male to female ratio was 1:2. Half of the cases occurred in farmers. Seventy-eight cases had a history of injury. One hundred and eight cases showed the cutaneous lymphangitic type and 92 cases showed the localized cutaneous type. The face and upper extremities were the most frequently affected sites. The sporotrichin skin test was positive in 96.3% of the cases. The causative organism was demonstrated in tissue sections in 94.5% of the cases.

Adolescent↗
PubMed1986

Serum and urinary oestrone sulphate in pregnancy and delivery measured by a direct radioimmunoassay.

Serum and urinary levels of oestrone sulphate in pregnancy and delivery were measured by a direct radioimmunoassay without hydrolysis. The serum and urinary oestrone sulphate increased as pregnancy progressed. The mean level of serum oestrone sulphate increased to the highest peak of 494 pmol/ml at the 35th gestational week and then decreased. The mean level of urinary oestrone sulphate increased to the highest peak of 1.28 mumol/l at the 34th gestational week and then decreased. At vaginal deliveries, the mean level of maternal peripheral serum oestrone sulphate increased hourly at as high a level as 979 pmol/ml. The mean serum level of oestrone sulphate was 204 pmol/ml in the umbilical artery and 145 pmol/ml in the umbilical vein. At Caesarean section, on the other hand, the maternal peripheral serum level of oestrone sulphate averaged 362 pmol/ml. The mean serum levels of oestrone sulphate were 90.7 pmol/ml and 171 pmol/ml in the umbilical artery and umbilical vein, respectively. These results suggest a maternal origin of oestrone sulphate in pregnancy, with fluctuations in the levels being of interest in relation to labour pain.

Cesarean Section↗