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T Ueda

Publications and source records attributed to T Ueda.

At least 595 records · Page 33Linked to original sources
PubMed1996

Action spectrum for sporulation and photoavoidance in the plasmodium of Physarum polycephalum, as modified differentially by temperature and starvation.

The plasmodium of the myxomycete Physarum polycephalum sporulates in bright natural environments, suggesting a relationship between photobehavior and sporulation. Thus, the action spectra for two light-dependent phenomena as well as the effects of other environmental conditions have been studied. Sporulation like photo-avoidance responded to UVC (near 270 nm) and near IR (near 750 nm) in addition to the well-documented UVA (near 350 nm) and blue (near 460 nm) regions. Sporulation and photoavoidance had similar sensitivities in the shorter wavelengths, while the former was about 100 times more sensitive in near IR. The plasmodium moved away from light in a wide spectral range. Starvation and high temperature at 31 degrees C (25 degrees C in standard conditions) reduced photoavoidance to UVA and to blue light, respectively. A high fluence rate of UVC suppressed the rhythmic contraction of the plasmodium, and the action spectrum peaked at 270 nm. These results indicate that the Physarum plasmodium may stay at brighter places not by positive phototaxis but by weakening the negative phototaxis to sunlight or by other possible taxes such as hydrotaxis. There may be at least four different photo-systems in the plasmodium.

Animals↗
PubMed1996

T lymphocytes and silica-induced pulmonary inflammation and fibrosis in mice.

BACKGROUND: Silica-induced pulmonary inflammation and fibrosis in animals provides a good model for chronic pulmonary inflammation and fibrosis. Although lymphocytes are implicated in the pathogenesis of pulmonary fibrosis, experimental models using silica-treated athymic nude mice have not been successful in showing the fibrogenic mechanism regulated by T cells. The aim of this study was to re-evaluate the role of T lymphocytes in the development of silicosis by comparing the response to silica administration of nude athymic mutants with that of euthymic animals. METHODS: Suspensions of silica particles were transnasally administered to nude athymic mice (Balb/c nu/nu) as well as to their euthymic littermates (Balb/c nu/+). The degree of pulmonary inflammation and fibrosis was assessed on days 14, 28, and 56 based upon histological observation, analysis of collagen deposition in the lungs, and analysis of the cellular constituent, protein, and phospholipid content in the bronchoalveolar lavage fluid. RESULTS: Histologically, athymic mice developed less severe interstitial pneumonitis than euthymic mice. In euthymic mice the lung hydroxyproline content increased with time after silica administration from 6.48 (0.38) micrograms hydroxyproline/mg dry lung weight on day 0 to 8.87 (0.41) micrograms/mg on day 56. A gradual increase in lung hydroxyproline content was also observed in athymic mice but the increase was significantly smaller than in euthymic mice (6.63 (0.43) micrograms/mg on day 0, 7.90 (0.19) micrograms/mg on day 56). Administration of silica resulted in an increase in the number of macrophages and neutrophils and in the total protein and phospholipid content of the bronchoalveolar lavage (BAL) fluid in both mouse strains. No significant difference was detected between athymic and euthymic mice in the numbers of macrophages, but the increase in neutrophils in the BAL fluid of athymic mice was significantly smaller than in euthymic mice on days 14 and 56. The total protein and phospholipid content of the BAL fluid from athymic mice was lower than that from euthymic mice. CONCLUSIONS: T lymphocytes appear to be involved in the pathogenesis of silica-induced pneumonitis. Since pulmonary fibrosis develops even in nude athymic mice, T cells do not seem to play a primary part in fibrogenic response but they regulate, at least to some extent, the response of inflammatory cells and fibrogenesis of the lung.

Animals↗
PubMed1996

Surfactant metabolism in transgenic mice after granulocyte macrophage-colony stimulating factor ablation.

Mice made granulocyte macrophage-colony stimulating factor (GM-CSF)-deficient by homologous recombination maintain normal steady-state hematopoiesis but have an alveolar accumulation of surfactant lipids and protein that is similar to pulmonary alveolar proteinosis in humans. We asked how GM-CSF deficiency alters surfactant metabolism and function in mice. Alveolar and lung tissue saturated phosphatidylcholine (Sat PC) were increased six- to eightfold in 7- to 9-wk-old GM-CSF-deficient mice relative to controls. Incorporation of radiolabeled palmitate and choline into Sat PC was higher in GM-CSF deficient mice than control mice, and no loss of labeled Sat PC occurred from the lungs of GM-CSF-deficient mice. Secretion of radiolabeled Sat PC to the alveolus was similar in GM-CSF-deficient and control mice. Labeled Sat PC and surfactant protein A (SP-A) given by tracheal instillation were cleared rapidly in control mice, but there was no measurable loss from the lungs of GM-CSF-deficient mice. The function of the surfactant from GM-CSF-deficient mice was normal when tested in preterm surfactant-deficient rabbits. GM-CSF deficiency results in a catabolic defect for Sat PC and SP-A.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed1996

Preventive effect of natural and synthetic antioxidants on lipid peroxidation in the mammalian eye.

Lipid peroxidation was initiated with 5 mM ferric iron and aliquots of bovine or porcine retina, purified rod outer segments (ROS) and retinal pigment epithelium (RPE). After 30 min of oxidation, the lipid hydroperoxide content of the tissues increased approximately 4- to 8-fold over control levels with ROS showing the greatest change and RPE the lowest. Eight lipid and aqueous antioxidants from natural or synthetic sources and five flavonoids were evaluated for their ability to inhibit the reaction. Species differences were observed with regard to the fraction under study. Palm oil-derived vitamin E showed significant protection in bovine retina, ROS and RPE. In the porcine eye, the major defense was also afforded by vitamin E, but MCLA and other compounds such as EPC-K1 and U74500A were all quite active at 10(-5) M concentration. Of the flavonoids tested, partial protection in the bovine retina was found at 10(-5) M levels for epigallocatechin gallate (EGCg), quercetin, diosmetin and pycnogenol. When vitamin E and EGCg or quercetin were combined, the individual effect was enhanced. These results demonstrate the usefulness of an in vitro model system that can rapidly and accurately determine the capacity of antioxidants against lipid peroxidation.

Animals↗
PubMed1996

Change in properties of exogenous surfactant in injured rabbit lung.

We asked if the function of surfactant could be enhanced after exposure to injured lungs. We also asked if sensitivity to inhibition of the minimal surface-tension-lowering properties of surfactant by plasma could be altered. Lung injury in rabbits was induced with N-nitroso-N-methylurethane (NMU) and 6 of 17 NMU-injured rabbits were treated with 100 mg/kg surfactant. All rabbits were ventilated for 2 h, and large aggregate alveolar surfactant was isolated by centrifugation. In vivo function of the large aggregate surfactant was evaluated by treatment of preterm surfactant-deficient rabbits at 27 d gestation. Surfactant from NMU-injured lungs increased compliance from 0.37 +/- 0.01 in control preterm rabbits to 0.71 +/- 0.05, a value significantly higher than found for the surfactant used for treatment (0.55 +/- 0.04) (p < 0.05). The minimal surface tensions of large aggregate surfactant and the surfactant used for treatment (0.1 mg lipid/ml) were evaluated for inhibition by plasma proteins. Surfactant from NMU-injured and surfactant-treated rabbits was more resistant to inhibition (minimal surface tension, 5.7 +/- 3.9 dyne/cm in the presence of 0.6 mg/ml plasma protein) than the surfactant used for treatment (19.7 +/- 0.8 dyne/cm). These results indicate that after exposure to the injured lung, the function of the surfactant used for treatment was enhanced and made less sensitive to plasma inhibition of the surface-tension-lowering properties of surfactant. These changes probably result from the association of endogenous surfactant components with exogenous surfactant.

Animals↗
PubMed1996

Bioactive saponins and glycosides. IV. Four methyl-migrated 16,17-seco-dammarane triterpene gylcosides from Chinese natural medicine, hoveniae semen seu fructus, the seeds and fruit of Hovenia dulcis THUNB.: absolute stereostructures and inhibitory activity on histamine release of hovenidulciosides A1, A2, B1, and B2.

Four bioactive methyl-migrated 16,17-seco-dammarane type triterpene glycosides called hovenidulciosides A1, A2, B1, and B2 were isolated from a Chinese natural medicine, Hoveniae Semen Seu Fructus, the seeds and fruit of Hovenia dulcis THUNB. (Rhamnaceae) together with hoduloside III and (+)-gallocatechin. The absolute stereostructures of hovenidulciosides A1, A2, B1, and B2 have been elucidated by chemical and physicochemical evidence. All were found to inhibit the histamine release from rat peritoneal exudate cells induced by compound 48/80 and calcium ionophore A-23187.

Animals↗
PubMed1996

Oxidative damage and enhanced erythrophagocytosis in canine erythrocytes infected with Babesia gibsoni.

Oxidative damage to canine erythrocytes infected with Babesia gibsoni was investigated. B. gibsoni was cultured together with erythrocytes from normal dogs. When parasitemia reached a peak level, concentrations of both methemoglobin (metHb) and malondialdehyde (MDA), an end product of lipid peroxidation, in erythrocytes were significantly higher than at cultivation Day 0. In addition, B. gibsoni-infected dogs with high parasitemia showed significant increases of both metHb and MDA concentration in erythrocytes compared to those in uninfected dogs. Furthermore, erythrocytes from parasitized culture were more susceptible to phagocytosis by bone marrow macrophages from normal dogs than erythrocytes from the control culture. In addition, macrophages ingested not only parasitized erythrocytes but also non-parasitized cells. These results suggested that oxidative damage to erythrocytes was induced by the multiplications of B. gibsoni, and that non-parasitized erythrocytes were also exposed erythrocytes oxidative stress during the infection by B. gibsoni.

Animals↗
PubMed1996

[Self-acceptance as adaptively resigning the self to low self-evaluation].

In past studies, the concept of self-acceptance has often been confused with self-evaluation or self-esteem. The purpose of this study was to distinguish these concepts, and operationally define self-acceptance as Carl Rogers proposed: feeling all right toward the self when self-evaluation was low. Self-acceptance as adaptive resignation, a moderating variable, therefore should raise self-esteem of only those people with low self-evaluation. Self-acceptance was measured in the study as affirmative evaluation of own self-evaluation. Two hundred and forty college students, 120 each for men and women, completed a questionnaire of self-evaluative consciousness and self-esteem scales. Results of statistical analyses showed that among subjects with low self-evaluation, the higher self-acceptance, the higher the person's self-esteem. The same relation was not observed among those with high self-evaluation. Thus, it may be concluded that self-acceptance was adaptive resignation, and therefore meaningful to only those with low self-evaluation.

Adaptation, Psychological↗
PubMed1996

Urinary calculi as a late complication of the Indiana continent urinary diversion: comparison with the Kock pouch procedure.

PURPOSE: Although urinary calculi have been frequent late complications of the Kock continent urinary diversion, they have not been regarded as significant problems in patients with the Indiana pouch because of the lack of foreign material present. However, stones developed in a significant percentage of our patients with an Indiana pouch. We investigated the characteristics of stone formation in patients with the Indiana pouch and compared them to those with a Kock pouch. MATERIALS AND METHODS: Detailed clinical courses regarding stone formation were reviewed in 72 patients with a Kock pouch and 54 with an Indiana pouch who had a minimum followup of 12 months. RESULTS: Stones developed in 7 of 54 patients (12.9%) with an Indiana pouch compared to 31 of 72 (43.1%) with a Kock pouch. The incidence gradually increased with longer followup but it was lower in the Indiana than in the Kock pouch group (5-year stone-free rate 84% versus 66%, respectively). Although the stones consisted principally of a mixture of struvite, carbonate apatite and ammonium hydrogen urate, variable amounts of calcium oxalate were identified in 50% of the Indiana pouch calculi. CONCLUSIONS: Not only urinary infections but also metabolic factors were considered to be involved in stone formation within the Indiana pouch. However, the substantially higher rate of stone formation in our Kock and Indiana pouch groups than has been reported in the United States suggested that no or infrequent pouch irrigations in our patients were important risk factors for urinary calculi.

Case-Control Studies↗
PubMed1996

Hepatic distribution of blood flow from the superior or inferior mesenteric vein mapped by portal scintigraphy with iodine-123-iodoamphetamine.

UNLABELLED: We previously reported the clinical meaning of measurements of the relative contributions of the superior and inferior mesenteric veins with [123I]iodoamphetamine after oral (in an enteric capsule) and rectal administration. The same method was used to map blood flow in the liver from both of these veins in 82 subjects, 31 with chronic hepatitis and 51 with cirrhosis. METHODS: Three hours after administration of a capsule containing 22.8 MBq of [123I]iodoamphetamine, data showing hepatic blood flow from the superior mesenteric vein were collected for 10 min. Next, 111 MBq of [123I]iodoamphetamine was administered rectally and data showing hepatic blood flow from the inferior mesenteric vein were collected for 30 min. Shunt indices from the superior and inferior mesenteric veins were calculated from these data. RESULTS: In patients with chronic hepatitis, blood from the superior mesenteric vein flowed into the right lobe or both lobes, but, in some patients with cirrhosis, blood from this vein flowed into the left lobe. In some patients with chronic hepatitis, blood from the inferior mesenteric vein flowed into the left lobe, but, in most patients with cirrhosis, the liver was not visualized during this examination and evaluation was not possible. Of the 53 patients in whom blood flow from both veins could be evaluated, 47 had blood from the two veins mixed to some extent in the liver and 6 had portal streamlining, with blood from the superior mesenteric vein going to the right lobe and blood from the inferior mesenteric vein going to the left lobe. CONCLUSION: These results suggest that blood flow in the superior and inferior mesenteric veins can be found mixed in the liver in most subjects with liver disease.

Amphetamines↗
PubMed1996

Diagnosis by routine scintigraphy of hepatic reticuloendothelial failure before severe liver dysfunction.

OBJECTIVES: The prognosis of hepatic reticuloendothelial failure is said to be poor. Scanning with the radiocolloid 99mTc phytate is needed for diagnosis; as a rule; only seriously ill patients are so investigated. We use 99mTc phytate for liver scans of almost all inpatients with liver disease. This routine made diagnosis of a mild form or early stage of the disease possible. We evaluated the clinical findings of the five patients we have diagnosed, in an attempt to find why four survived. METHODS: Radiocolloid scans were taken starting 20-30 min after the intravenous injection of 111 MBq of 99mTc phytate. Hepatobiliary images were taken by use of 99mTc pyridoxylidine-5-methyl trytophan, and hepatic receptor images were taken by use of 99mTc-labeled diethylenetriaminepentaacetic acid coupled with galactosyl human serum albumin. RESULTS: The livers were not visible in the radiocolloid scans, so the diagnosis of hepatic reticuloendothelial failure was considered. In the two other imaging examinations, the livers were visible. The cause was identified as heavy alcohol intake in four cases and toluene hepatotoxicity in one case. Histological examinations showed cirrhosis in two patients; the three other patients did not have cirrhosis. All five patients had anemia, and three had infections. One patient died of multiple organ failure, and the four other patients survived. Long-term observation by radiocolloid scanning was possible in one patient in whom radionuclide uptake into the liver rose as hepatic function improved. CONCLUSIONS: This disorder is associated with a temporary decrease in Kupffer cell function and hence is liable to be complicated by infection, which can result in death. If the cause is removed promptly, recovery is likely. There being a mild form of this disease, previously not generally diagnosed, probably accounts for the outcomes being good in all of our patients except the one patient with severe liver dysfunction at the time of diagnosis.

Adult↗
PubMed1996

Role of serine and ICE-like proteases in induction of apoptosis by etoposide in human leukemia HL-60 cells.

This study was undertaken to examine the role of proteases in etoposide-induced apoptosis of human leukemia HL-60 cells. We found the potent activity to produce internucleosomal DNA fragmentation in a 150 000 g supernatant of cell lysate which was prepared from etoposide-treated HL-60 cells undergoing apoptosis. This nuclear-DNA fragmenting activity could be detected when the supernatant was incubated with isolated nuclei under Mg2+-dependent conditions. On the other hand, we could not detect such activity in the supernatant of cell lysate from non-treated HL-60 cells. Treatment of the supernatant with a serine protease inhibitor, N-tosyl-L-phenylala-nylchloromethyl ketone (TPCK), abolished the DNA fragmenting activity. An inhibitor of interleukin 1-beta-converting enzyme (ICE), Z-Val-Ala-Asp-fluoromethyl ketone (VAD-FMK), had no effect on this DNA fragmenting activity in vitro. However, when the cells were incubated with etoposide in the presence of VAD-FMK, the formation of TPCK-sensitive DNA fragmenting activity was blocked. Our data indicate that serine and ICE-like proteases may be involved in etoposide-induced apoptosis at the different stages, and especially a serine protease may be closely associated with the final step for induction of internucleosomal DNA fragmentation during apoptosis in HL-60 cells.

Amino Acid Chloromethyl Ketones↗
PubMed1996

Fulminant hepatic failure monitored by technetium-99m-DTPA-galactosyl-human serum albumin scintigraphy.

We describe a 43-yr-old woman with fulminant hepatic failure whose progress was monitored scintigraphically using 99m-Tc-galactosyl-human serum albumin (99mTc-GSA). On admission, the liver was atrophic and the heart was delineated distinctly by scintigraphy with 99m-Tc-GSA. The receptor index, calculated by dividing the radioactivity of the liver region of interest by the radioactivity of the liver plus heart regions of interest at 15 min post-tracer injection, was very low. As the patient's condition improved, the right lobe of the liver enlarged while the left lobe became atrophic; after 4 mo, the left lobe almost completely disappeared. Delineation of the heart gradually became less distinct, and the receptor index slowly increased. Hepatic receptor imaging with 99m-Tc-GSA can define both the hepatic functional reserve and morphological changes of the liver, so it is useful for the diagnosis and follow-up study of fulminant hepatic failure.

Adult↗
PubMed1996

[Ureteral malacoplakia: a case report].

Malacoplakia is a condition which occurs most often in the urogenital system, but ureteral malacoplakia is rare. A case of ureteral malacoplakia is presented. The patients was a 54-year-old woman admitted to our hospital with high fever as the chief complaint. Laboratory data suggested urinary tract infection. Escherichia coli were isolated from the urine. Ultrasonography indicated left hydronephrosis and excretory urography showed reduced function of the left kidney. From retrograde pyelography, obstruction of the left distal ureter was indicated. A ureteral carcinoma was suspected and nephroureterectomy was thus carried out. The histopathological diagnosis was malacoplakia. The patient is in good health without any indication of the disease at 1 year 9 months following surgery.

Female↗
PubMed1996

[Surgery for WPW syndrome with concomitant CABG: a case report].

A 58-year-old man underwent simultaneous surgery for WPW syndrome complicated by frequent attacks of atrial tachyarrhythmia combined with angina pectoris persisting after anterior myocardial infarction. Repeated PTCA of 3 times failed and restenosis occurred with recurrent angina particularly when atrial tachyarrhythmia took place. The preoperative ECG suggested the presence of a left free wall accessory pathway confirmed by an electro-physiolosical study. Coronary bypass grafting (LITA-LAD, SVG-4 PD) and division with cryoalation of the accessory pathway were performed using a transseptal left atrial approach. The patient is doing well now and free from both angina and tachycardia.

Angina Pectoris↗
PubMed1996

[The mechanism of apoptosis induced by anticancer agents in human leukemia cells].

Many anticancer agents induce apoptosis in human leukemia cells. Among the various leukemia cells, especially HL-60 cells and U937 cells are very sensitive to apoptosis upon anticancer agents treatment. A serine protease inhibitor TPCK and an ICE-like protease inhibitor VAD-FMK prevented etoposide, camptothecin and ara-C-induced internucleosomal DNA cleavage in human myeloid leukemia HL-60 and U937 cells. Using a cell-free system, we have examined the inhibitory mechanism of these inhibitors on anticancer agent-induced internucleosomal DNA cleavage. Our data indicate that serine and ICE-like proteases may be involved in anticancer agent-induced apoptosis at the different stages, and especially a serine protease may be closely associated with the final step for induction of DNA fragmentation during apoptosis in human myeloid leukemia HL-60 and U937 cells.

Antineoplastic Agents↗
PubMed1996

[Bilateral renal cell carcinoma with extension into the vena cava associated with von Hippel-Lindau disease: a case report and review of the literature].

We report a case of bilateral renal cell carcinoma with extension into the inferior vena cava associated with von Hippel-Lindau (VHL) disease. A 52-year-old woman was referred to our hospital for further examination of bilateral renal masses which were found on abdominal ultrasound examination. The diagnosis was confirmed with renal angiography, abdominal computed tomography (CT), abdominal magnetic resonance-CT (MRI), cavography and head MRI. Right adjunctive nephrectomy and removal of the tumor thrombus were performed. She has been treated with interferon-alpha after the operation. The analysis of her DNA by using single strand conformational polymorphism revealed a VHL gene abnormality.

Carcinoma, Renal Cell↗