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T Uehara

Publications and source records attributed to T Uehara.

At least 19 recordsLinked to original sources
PubMed1992

Differential expression of apoptosis-related Fas antigen on lymphocyte subpopulations in human peripheral blood.

The Fas Ag is a newly defined cell-surface molecule that may mediate apoptosis. The antibody against Fas Ag can induce the apoptotic cell death in cell lines expressing this Ag. PBL subpopulations at various ages were here examined for Fas expression by two-or three-color flow-cytometric analyses using anti-Fas mAb. It was found that Fas Ag was appreciably detected on a proportion of T and B cells, whereas its expression was absent for NK cells. For CD4+ and CD8+ T cells, Fas Ag was expressed preferentially on CD45RO+ (memory or previously activated) populations, but not on CD45RO- naive ones. TCR-gamma/delta+ T cells, especially their CD45RO+ subsets, also expressed Fas Ag. Expectably, neonatal T cell subpopulations, most of which had the naive (CD45RO-) phenotype, expressed little Fas Ag. Fas-expressing B cells dominated in surface(s) IgD- populations, but neonatal B cells as well as adult sIgD+ B cells had little Fas Ag. The Fas Ag was inducible after in vitro mitogenic stimulation of naive T and B cells from neonatal blood. These observations suggested that expression of Fas Ag on T and B cells in the peripheral blood might reflect their in vivo Ag-activated status. In contrast to Fas-expressing cultured cell lines, however, viability of in vitro stimulated T and B cells as well as freshly isolated CD45RO+ T cells was not significantly changed after the treatment with anti-Fas mAb, indicating that additional cellular conditions to Fas expression might be required for anti-Fas-induced cell death.

Antigens, Surface↗
PubMed1992

[Detectability of diagonal branch disease by 201TlCl exercised myocardial scintigraphy].

The detectability of diagonal branch disease in 10 patients (five with angina pectoris, five with myocardial infarction) with isolated diagonal branch lesions (more than 75% luminal stenosis in coronary angiography) was reviewed. In exercised 201TlCl myocardial scintigraphy, chest pain occurred in four of 10 patients, electrocardiographic change indicating myocardial ischemia was seen in four, and diagonal branch lesion was detected in only four patients by planar images. In contrast, diagonal branch lesions were detected in 10 of 10 patients by SPECT (single photon emission computed tomography). In planar images, perfusion defects appeared high in the anterolateral, posterolateral, and anterior walls of the left ventricle. In SPECT images they appeared high in the anterior to anterolateral wall. The extent of diagonal branch lesions could be quantitatively evaluated by coronary territory maps developed from unfolded maps of exercised SPECT. The mean ratio of the extent of diagonal branch lesion to left anterior descending branch territory was 24.7%, and the extent of myocardial infarction was significantly larger than that of angina pectoris (p < 0.05). In conclusion, SPECT is useful for detecting diagonal branch lesions and can quantitatively show the extent of these lesions by coronary territory map.

Aged↗
PubMed1992

[Raise up 99mTc-HMPAO brain SPECT for detecting the changes in cerebral perfusion pressure].

99mTc-HMPAO crossed the blood brain barrier instantly in proportional to cerebral blood flow. Raise up stress and supine resting 99mTc-HMPAO with brain SPECT was devised for detecting abnormal response in the changes of cerebral perfusion pressure. Asymmetric ratio in the middle cerebral artery area in patients with internal carotid artery occlusion (n = 5) was changed significantly from 0.82 +/- 0.06 to 0.90 +/- 0.06 and that of normal (n = 5) was not changed from 0.94 +/- 0.03 to 0.95 +/- 0.01. Raise up 99mTc-HMPAO brain SPECT enhanced the detectability in abnormality of regional cerebral blood flow and visualized the dys-autoregulated area during blood pressure falls.

Blood Pressure↗
PubMed1992

Apoptotic cell death of primed CD45RO+ T lymphocytes in Epstein-Barr virus-induced infectious mononucleosis.

The expansion of activated T cells, characterized by the expression of CD45RO as well as HLA-DR antigens, is a central feature in acute infectious mononucleosis (IM) induced by primary infection of Epstein-Barr virus (EBV). However, the fate of these activated T cells in this disease is not clearly understood. We found that, on simple culture, a large proportion of T cells isolated from acute IM patients died rapidly, but only a few T cells from normal individuals did. Morphologic observations and DNA fragmentation analysis showed that the loss of viability of IM T cells after incubation was mediated by apoptosis. IM T cells undergoing apoptosis resided exclusively in the CD45RO+ populations of both CD4+ and CD8+ T cells, most of which were shown to coexpress apoptosis-related Fas antigen. Some cytokines such as interleukin-2 (IL-2), IL-5, and IL-6 could rescue IM T cells from apoptotic cell death. The results seemed to imply that most of primed (CD45RO+) T cells in acute IM might be subject to apoptotic cell death, possibly when leaving from the local sites actively producing certain soluble factors required for their survival. Our studies suggest the programmed cell death of peripheral mature T cells as a mechanism of antigen-driven selection.

Antigens, CD↗
PubMed1992

Increased peptidylarginine deiminase expression during induction of prolactin biosynthesis in a growth-hormone-producing rat pituitary cell line, MtT/S.

Insulin and type I insulin-like growth factor (IGF-I) suppressed growth hormone (GH) expression followed by the induction of prolactin (PRL) biosynthesis in MtT/S cells cultured with normal sera. Insulin also increased the peptidylarginine deiminase activity in a dose-dependent manner. The increase was detectable at 1 ng/ml and reached a maximum (about 16-fold higher than the control) at 1 micrograms/ml. IGF-I showed similar but less prominent effects. The enzyme activity started to increase by 15 hr after the addition of insulin (500 ng/ml), and reached a plateau level at 48 hr. There were concurrent increases in the enzyme mRNA level, enzyme biosynthesis, and enzyme protein contents detected by Northern blot hybridization, [35S]-amino-acid incorporation, and Western immunoblot analysis, respectively. Two-color immunofluorescence staining at 1 day after the insulin addition detected a small number of peptidylarginine-deiminase-positive cells (about 1% of the total cells) which were also GH-positive. The enzyme-positive cells increased to 12% on day 2 and to 24-26% on days 4-6. PRL-positive cells first appeared in the enzyme-positive cell population on day 2, and PRL-positive, enzyme-negative cells appeared later. These results suggest that peptidylarginine deiminase expression increases in association with the hormone switching in MtT/S cells. When the cells were cultured in a steroid-depleted medium, insulin failed to increase the enzyme activity. The insulin action could be specifically restored by estrogen, indicating estrogen-insulin synergism in regulation of the enzyme expression.

Animals↗
PubMed1992

Visualization of posture-dependent cerebral blood flow in a patient with Takayasu's disease by means of 99mTc-HMPAO brain single photon emission tomography.

A case of Takayasu's disease in a 22-year-old woman who complained of severe fainting attacks is presented. Bilateral obstruction of the cervical arteries was confirmed by digital subtraction angiography. Preoperative technetium-99m hexamethylpropylene amine oxime brain SPET in the sitting position showed bilateral hypoactivity in the temporoparietal areas. Subtraction brain SPET showed slightly increased activity in the lying position. The patient has had no fainting attacks since bypass surgery. Postoperative 99mTc-HMPAO brain SPET in the sitting position showed normal activity except in the right temporoparietal area. This area was filled in the lying position. 99mTc-HMPAO brain SPET is the only technique that can visualize the cerebral blood flow in any position, this capability deriving on the fact that the distribution of 99mTc-HMPAO in the brain is fixed in the first 2-3 min following injection. The use of both sitting and lying 99mTc-HMPAO brain SPET is very useful for detecting an abnormality (i.e. an inhomogeneous response due to the fall in perfusion pressure) that could not be seen if the cerebral blood flow were to be assessed only in the lying position.

Adult↗
PubMed1992

Serial assessment of denervated but viable myocardium following acute myocardial infarction in dogs using iodine-123 metaiodobenzylguanidine and thallium-201 chloride myocardial single photon emission tomography.

Iodine-123 metaiodobenzylguanidine (mIBG) is taken up by sympathetic nerve endings, allowing scintigraphic imaging of myocardial sympathetic innervation. We investigated the denervated but viable canine myocardium after acute myocardial infarction by serial mIBG and thallium-201 chloride (201TlCl) single photon emission tomography (SPET). In 12 dogs, acute myocardial infarction was produced by ligation of the left circumflex coronary artery. Images of mIBG and thallium SPET were obtained 6 h, 1, 4 and 6 weeks later. The defect size was calculated in percentage points from short axial views, and the 123I-mIBG/201TlCl ratio was determined. The uptake ratio was high at 1 week but gradually decreased. Three dogs were killed at each time point, and tissue samples were obtained from infarcted (both 201TlCl and 123I-mIBG defects), peri-infarcted (123I-mIBG defect and 201TlCl normal) and normal myocardium (both mIBG and 201TlCl normal). The changes in tissue content of noradrenaline in these lesions were measured. Noradrenaline tissue content gradually recovered in the peri-infarcted area. However, no recovery was noted in the infarcted area at 6 weeks. We conclude that sympathetic denervation and re-innervation occur following acute myocardial infarction, and the denervated but viable myocardium could be detected non-invasively by combined mIBG and thallium SPET.

3-Iodobenzylguanidine↗
PubMed1992

Coronary arterial involvement in aortitis syndrome: assessment by exercise thallium scintigraphy.

It is important in patient management to evaluate coronary arterial involvement in aortitis syndrome. Twenty-one cases of aortitis syndrome who experienced chest pain were examined using exercise thallium scintigraphy. The patients were divided into 4 groups according to the angiographic findings. There were five patients with left main coronary arterial involvement (group A), four with left or right coronary arterial involvement (group B), nine with aortic regurgitation (group C), and three with pulmonary arterial involvement (group D). In groups A and B, all patients had positive ECGs and thallium perfusion defects. Group A patients showed extensive anterolateral perfusion defects, which were compatible with left main coronary arterial involvement. Groups C and D patients, who had normal coronary arteries, showed no remarkable perfusion defects although five had positive ECG findings. Thus, the sensitivity and specificity of exercise scintigraphy for detection of myocardial ischemia were 9/9 and 12/12, while those of stress ECG were 9/9 and 7/12 (58%), respectively. it is recommended that exercise thallium scintigraphy be used for detecting clinically occult but significant coronary arterial involvement in aortitis syndrome with chest pain.

Adult↗
PubMed1992

Favorable biodistribution of 99mTc-ECD for brain SPECT comparing with 123I-IMP using alternative body scan.

In order to evaluate the lung and brain uptake of 99mTc ethyl cysteinate dimer (99mTc-ECD) and N-isopropyl-p-[123I]-iodoamphetamine (123I-IMP), alternative body scans were carried out in 15 cases of cerebrovascular disease. The biodistribution of 99mTc-ECD was 5.5 +/- 0.7%, 3.8 +/- 0.7% in the brain; 13.1 +/- 3.7%, 2.2 +/- 1.2%, in the lung at 15 min and at 4 hours, respectively, whereas that of 123I-IMP was 3.9 +/- 1.4%, 5.0 +/- 1.0% in the brain; 32.2 +/- 7.6%, 12.7 +/- 3.3%, in the lung at 15 min and at 4 hours, respectively. 99mTc-ECD accumulated in comparatively high amounts in the brain but remained low in the lung in the early image compared to 123I-IMP. However there was a high inverse correlation between brain and lung uptake of 123I-IMP (r = -0.82), but not of 99mTc-ECD (r = -0.18). We concluded that 99mTc-ECD had a better biodistribution in terms of low lung accumulation than 123I-IMP in brain SPECT.

Aged↗
PubMed1992

[Clinical study of albendazole therapy for strongyloidiasis].

We reported the efficacy of albendazole (ABZ) for the treatment of 27 patients with strongyloidiasis. Twenty-seven patients, 23 males and 4 females, received 200 mg of ABZ one hour before breakfast and supper for 3 days and this treatment was repeated 2 weeks later. The following results were obtained: 1) The eradication rate at 2 weeks after the initial treatment was 70.4% (19 of 27 patients) and 2 weeks after the second course was 66.7% (16 of 24 patients). 2) One patients (3.7%) complained of abdominal pain after the first treatment. Four patients (14.8%) complained of headache (n = 2), nausea (n = 1) and exanthema (n = 1) after the second treatment. But all symptoms were mild and required no treatment and subsided in a few days. 3) Positive rate of HTLV-1 antibody was 45.8% in the patients. As described above, side effects occurred in some cases, although they were mild and transient. From these results, it can be concluded that on increased dose of ABZ could be much more favorable for the treatment of strongyloidiasis.

Adult↗
PubMed1992

[Clinical study on symptoms in patients with strongyloidiasis].

We treated strongyloidiasis patients and obtained the following results: Of the 299 patients (184 males and 115 females), 81 patients (27.1%) had no complaints before treatment, 218 patients complaints of some symptoms, including arthralgia and/or lumbago (28.4%), abdominal pain and/or borborygmus (19.3%), numbness of extremities (18.1%), constipation (16.3%) and itching (15.7). We treated 219 patients with mebendazole and symptoms improved after treatment described below: Thirty-seven of the 63 patients (58.7%) with arthralgia and/or lumbago improved. Twenty-seven of the 36 patients (75.0%) with numbness of extremities improved. Thirty-one of the 32 patients (96.9%) with heartburn improved. We treated 26 patients with mebendazole plus thiabendazole and twelve of 14 patients (85.7%) with abdominal pain and/or borborygmus were improved after treatment. We treated 54 patients with ivermectin and five of 18 patients (27.8%) with arthralgia and/or lumbago were improved after treatment.

Adult↗
PubMed1992

[Clinical study of eradicated and resistant patients to treatment with ivermectin for strongyloidiasis].

We treated 70 patients with strongyloidiasis (41 males and 29 females) with ivermectin (IVM), and obtained the following results: 1. The eradication rates at 1-2 months, 3-4 months and 5-6 months after treatment were 90.7% (49 of 54 patients), 100.0% (47 of 47 patients) and 95.7% (45 of 47 patients), responsively. Twelve patients were resistant (non-responsive) to treatment. 2. When compared to patients whose parasites were completely eradicated, the resistant patients showed the following results: 1) Incidence of symptoms observed before treatment was significantly lower (50.0% vs. 84.5%). 2) Positive rate of anti-HTLV-I antibody was significantly higher (66.7% vs. 20.7%). 3) Blood eosinophil counts before treatment were significantly lower (266.6 +/- 117.2/mm3 vs. 533.2 +/- 429.7/mm3). 4) Serum IgE levels before treatment were significantly lower (217.2 +/- 442.9 IU/ml vs. 1,076.8 +/- 2,108.0 IU/ml). 5) There were no significant differences in age, sex and dosage of ivermectin. 3. Comparing anti-HTLV-I antibody positive and negative patients, the following results were obtained: 1) Eradicated patients; a) Eosinophils and IgE levels before and after the first administration of medicine in anti-HTLV-I antibody positive patients were significantly lower than those of negative patients. b) Gammaglobulin levels before treatment and after both administrations of the drug, IgG before therapy and OKT4/OKT8 after therapy were significantly higher than in anti-HTLV-I antibody positive patients. 2) Resistant patients; Eosinophils after treatment were significantly lower in anti-HTLV-I antibody negative patients than in positive patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

Defective production of interleukin-6 in very small premature infants in response to bacterial pathogens.

In the present study, a whole-blood culture was employed to examine the ability of preterm and term newborn infants to produce interleukin-6 (IL-6) in response to major bacterial pathogens such as group B streptococci, Escherichia coli, Listeria monocytogenes, and Streptococcus pneumoniae. Similarly, in response to stimulation with lipopolysaccharide, a potent stimulant for monocyte cytokine production, appreciable levels of IL-6 activity in the stimulated whole blood from term newborns as well as adults was effectively induced by all of these pathogens. In contrast to that of term infants, the bacteria-induced IL-6 production of preterm infants, especially those born before 30 weeks of gestation, was somewhat decreased (P less than 0.01 for each pathogen). It was also demonstrated that IL-6 responses to lipopolysaccharide stimulation were reduced in preterm newborns (for term versus preterm newborns less than 30 weeks of gestation, P was less than 0.01). These findings imply some inherent abnormality of monocytes in preterm babies. The diminished IL-6 production may be partly responsible for the susceptibility of preterm newborn infants to bacterial infections.

Adult↗
PubMed1992

Assessment of myocardial viability by using newly developed myocardial SPECT imaging.

Thallium myocardial imaging has been widely available for the detection of myocardial ischemia and assessment of myocardial viability in coronary artery diseases. However, myocardial imaging using SPECT and gamma-emitting radiopharmaceuticals has been developed for accurate evaluation of myocardial infarction and ischemia. The present study was undertaken to clinically evaluate myocardial necrosis, metabolism and sympathetic nerve activity. In this study, myocardial fatty acid metabolism was assessed using 123I-BMIPP, myocardial sympathetic neural activity was assessed using 123I-MIBG and myocardial necrosis was assessed using 111-In-antimyosin Fab. Dual energy SPECT using these new agents and thallium gives precise characterization of myocardial viability in coronary artery disease.

3-Iodobenzylguanidine↗
PubMed1992

Efficacy of ivermectin against Strongyloides stercoralis in humans.

Okinawa Prefecture is an endemic area of Strongyloides stercoralis infection. Since treatment of this infection remains unsatisfactory, we evaluated the efficacy of ivermectin. Twenty-three patients were treated with a single oral dose of ivermectin (mean +/- SD, 105.5 +/- 20.8 mcg/kg of body weight), followed by a second dose two weeks later. The rate of cure was 85.7% at 2 weeks after the first treatment, and 90.5% at 2 weeks after the second treatment. Side effects occurred in 2 patients (8.7%), but they were mild and transient. The results indicate that ivermectin might be useful and relatively safe for the therapy of Strongyloides stercoralis infection as an alternative to thiabendazole or mebendazole.

Aged↗
PubMed1992

Hereditary angioedema: a case with ascites yet no symptoms in the family.

An interesting case of hereditary angioedema in a 26-year-old female is reported, with a finding of transient effusion of fluid into the peritoneal cavity during the attacks. The patient suffered from recurrent abdominal pain for several years, but no family members had any similar symptoms. In spite of repeated hospital admissions and many examinations, accurate diagnosis was not made until the most recent admission. The recognition of hereditary angioedema as a cause of acute and/or recurrent abdominal pain may avoid useless invasive procedures and lead to adequate treatment in other similar cases.

Abdominal Pain↗