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T Ueda

Publications and source records attributed to T Ueda.

At least 631 records · Page 35Linked to original sources
PubMed1995

Suppression of pulmonary metastasis by angiogenesis inhibitor TNP-470 in murine osteosarcoma.

We treated a murine osteosarcoma cell line, LM8, which preferentially metastasizes to the lungs, with a new angiogenesis inhibitor, TNP-470, to evaluate the efficacy of this compound in the suppression of pulmonary metastasis of osteosarcoma. In an in vivo experiment, tumor cells were inoculated i.v. into C3H mice, and TNP-470 or vehicle alone (control group) was administered s.c. every day for 3 weeks. In the TNP-470-treated groups, both the number of pulmonary metastatic nodules and the lung wet weight were significantly reduced in a dose-dependent manner. Similarly, vascular density in the metastatic tumors estimated by immunohistochemical staining with anti-von-Willebrand factor antibody as an endothelial marker were significantly reduced. No severe side-effects were found. In an in vitro experiment, viable tumor cells were counted after 3 days' treatment with TNP-470. The 50% inhibitory concentration was 0.6 ng/ml for LM8, which was more sensitive than other tumor cells previously reported. Our results show that TNP-470 suppresses the pulmonary metastasis of LM8 and suggest that both its anti-angiogenic activity and cytostatic activity towards LM8 are responsible for the antitumor effect.

Animals↗
PubMed1995

Misincorporation of dAMP opposite 2-hydroxyadenine, an oxidative form of adenine.

Nucleotide incorporation opposite an oxidative form of adenine, 2-hydroxyadenine (2-OH-Ade) was investigated. When a primed template with 2-OH-Ade was treated with an exonuclease-deficient Klenow fragment of Escherichia coli DNA polymerase I (KFexo-), recombinant rat DNA polymerase beta (pol beta) or calf thymus DNA polymerase alpha (pol alpha), incorporation of dTMP and dAMP was observed. In addition, KFexo- inserted dGMP as well. A steady-state kinetic study indicated that the insertion of dAMP and dTMP opposite the DNA lesion occurred with similar frequency with KFexo- and pol beta. Insertion of dTMP opposite 2-OH-Ade was favored to that of dAMP by pol alpha. Chain extension from the A.2-OH-Ade pair is less favored than that from the T.2-OH-Ade pair by all three DNA polymerase. Analysis of full-length products of in vitro DNA synthesis showed that dTMP and dAMP were incorporated by DNA polymerases and that exonuclease-proficient and -deficient Klenow fragments also inserted dGMP opposite 2-OH-Ade. These results suggest that formation of 2-OH-Ade from A in DNA will induce A-->T and A-->C transversions in cells.

Animals↗
PubMed1995

Phenotypic instability of transgenic tobacco plants and their progenies expressing Arabidopsis thaliana small GTP-binding protein genes.

Chimeric genes consisting of the cauliflower mosaic virus 35S promoter, a cDNA encoding a small GTP-binding protein from Arabidopsis thaliana (ara-2 or ara-4) and the terminator of the nopaline synthase gene were cloned into a binary vector. Tobacco leaf tissues were transformed with this plasmid via Agrobacterium-mediated transformation. Transgenic plants possessing either ara-2 or ara-4 occasionally showed morphological abnormalities in leaves and other organs. However, such alterations were not always associated with co-transferred characters, such as kanamycin tolerance, and they arose in no more than 10% of the transgenic plants. Such phenomena were also observed in the progenies of the primary transgenic plants. Despite such unusual inheritance of the phenotypic abnormalities, GTP-binding activity of the inserted ara gene products was detected in all plants tested.

Arabidopsis↗
PubMed1995

Mammalian tissue trypsin-like enzymes: substrate specificity and inhibitory potency of substituted isocoumarin mechanism-based inhibitors, benzamidine derivatives, and arginine fluoroalkyl ketone transition-state inhibitors.

Amino acid and peptide thioesters which contained Arg or Lys in the P1 position were tested as substrates for rat skin tryptase, and the kinetic constants Kcat/KM for the better substrates such as Z-Aba-Arg-SBzl, and Z-Gly-Arg-SBzl were over 5,000,000 M-1 s-1. The inhibitory potency of arginine fluoroalkyl ketones, benzamidine derivatives, and substituted isocoumarins containing basic functional groups was studied with rat skin tryptase, human lung tryptase, human skin tryptase, and bovine trypsin. 1-Naphthoyl-Arg-CF3 was the best arginine fluoroalkyl ketone reversible inhibitor for rat skin tryptase with a KI of 0.9 microM. 1-(4-Amidino-phenyl)-3-(4-phenoxyphenyl) urea showed competitive inhibition against bovine trypsin and rat skin tryptase with KI values of 2 and 4 microM, respectively. Isocoumarin derivatives with isothioureidoalkoxy substituents at the 3 position were potent irreversible inhibitors of these three tryptases with Kobs/[I] values of 10(4)-10(5) M-1 s-1. 4-Chloro-3-(2-isothioureido)ethoxy-7-phenylcarbamoylaminoisocou marin and 7-benzylcarbamoylamino-4-chloro-3-(3-isothioureido)propox yisocoumarin inactivated trypsin and formed stable trypsin-inhibitor complexes which regained less than 8% of activity upon standing in the pH 7.5 buffer and regained 30-75% of activity in the presence of 0.3 M NH2OH after 1 day. In contrast, the complexes with rat skin tryptase regained activity rapidly, indicating differences in the inhibition mechanism and active site structures of these related enzymes.

Amino Acid Sequence↗
PubMed1995

The determination of nitrite and nitrate in human blood plasma by capillary zone electrophoresis.

The determination of nitrite and nitrate in human blood plasma by capillary zone electrophoresis (CZE) is described. Electrophoresis was carried out in a 65 cm long, 75 microns wide silica capillary, using 750 mM sodium chloride containing 5% NICE-Pak OFM Anion-BT (an additive reversing the electroosmotic flow) as running buffer, at a potential of 20 kV, with on-column UV detection at 214 nm. Under these conditions, the two anions migrated in the order of nitrite and nitrate, completely resolved from each other. Forty-one samples of ultrafiltered blood plasma of healthy volunteers were analyzed. The concentrations of nitrite and nitrate were 0.15 +/- 0.07 mg/L and 3.2 +/- 1.6 mg/L (mean +/- SD), respectively, with a linear correlation in the range of 0.1-50 mg/L. The within-day and between-day coefficients of variation (CVs) for nitrite and nitrate were lower than 5% and 8%, respectively. The recovery was 97-114%. The estimated plasma volume needed for each determination was 108 nL.

Electrophoresis, Capillary↗
PubMed1995

Adsorption-desorption of proteins on phospholipid polymer surfaces evaluated by dynamic contact angle measurement.

Adsorption-desorption of plasma protein on various polymer membranes was evaluated by a dynamic contact angle (DCA) measurement using the Wilhelmy plate method. Poly(ethylene terephthalate) (PET) was used as a substrate membrane; we examined this membrane coated with hydrophilic polymers such as poly[2-methacryloyloxethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (BMA)] or poly[2-hydroxyethyl methacrylate (HEMA)]. Although the zeta-potential of the PET membrane was negative, the coating with poly(MPC-co-BMA) induced increase of value to nearly zero. The DCA loops observed on the polymer membranes after protein adsorption were unity and hysteresis of the loop was reduced. In the cases of protein adsorbed on both the PET and the poly(HEMA) membranes, the shape and hysteresis of the loops were almost same during the rinsing process with a phosphate-buffered solution (PBS). However, the hysteresis of the DCA loops that appeared on the protein-adsorbed poly(MPC-co-BMA) membrane became large during the rinsing process with the PBS, and the shape of the DCA loop returned to its non-protein-adsorbed state. Therefore, proteins adsorbed on poly(MPC-co-BMA) could desorb more readily than those on PET and poly(HEMA) because of the weak interaction between poly(MPC-co-BMA) and the proteins.

Adsorption↗
PubMed1995

Use of a pericardial fat pad flap for preventing bronchopleural fistula: an experimental study focusing on the angiogenesis and cytokine production of the fat pad.

An experimental study was conducted to determine whether pericardial fat tissue could induce neovascularization and produce cytokines related to tissue repair. Neovascularization was examined using chick chorioallantoic membranes. Pieces of pericardial fat tissue, omentum, and intercostal muscle were individually placed on a number of chorioallantoic membranes and neovascularization induced by each material was assayed 6 days after the implantation. The intensity of neovascularization was in the order of pericardial fat > or = omentum > muscle. Cytokines, such as interleukin 1 (IL-1) alpha and beta, tumor necrosis factor-alpha (TNF alpha), interferon-gamma (IFN-gamma), and interleukin 6 (IL-6) were assayed in a culture supernatant of pericardial fat tissue. The latter was obtained 24 h after the addition of lipopolysaccharide (LPS) following various incubation times. All cytokines other than IFN gamma are known to play a part in tissue repair, whereas IFN gamma is negatively related to tissue repair because it inhibits fibroblast growth. The pericardial fat tissue incubated with LPS produced a certain amount of IL-1 on day 1, and TNF alpha on days 1 and 8, whereafter these values decreased to an undetectable level. Irrespective of the addition of LPS, a large amount of IL-6 was observed in the supernatant of pericardial fat tissue and it was detectable until day 29. On the contrary, INF gamma was not detected at any assay time. These observations suggest that a pericardial fat pad flap could possibly be beneficial in the prevention of bronchopleural fistula after pulmonary resection.

Adipose Tissue↗
PubMed1995

A new approach for performing a one-stage operation through the mediastinum to resect bilateral lung metastases: report of a case.

We describe herein a new operative technique for reaching the opposite lung from the thoracotomy site through the mediastinum. This procedure was successfully performed on a 76-year-old woman with bilateral lung metastases whose case is presented. After resection of the right lower lobe which contained two metastases, the anterior mediastinum was opened, and contralateral metastasis located in the lingular segment was resected using a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser. A chest drainage tube was inserted through the mediastinal window. This transmediastinal approach seems to be a feasible technique for preserving the respiratory function of the chest wall in patients with imbalanced bilateral metastases.

Aged↗
PubMed1995

Treatment of advanced hormone-refractory prostate carcinoma with a combination of etoposide, pirarubicin and cisplatin.

A total of 20 patients with hormone-refractory prostate carcinoma entered a pilot study of combination chemotherapy based on the EAP (etoposide, Adriamycin and cisplatin) regimen, in which Adriamycin was replaced by pirarubicin, a less cardiotoxic derivative of Adriamycin. The response was assessed by criteria modified from those of the National Prostatic Cancer Project: prostate-specific antigen was employed instead of acid phosphatase. Of 18 evaluable patients, 6 achieved a partial response, 5 had stable disease, and in 7 the disease had progressed during therapy; thus, the overall response rate was 33.3% [95% confidence interval (CI) 11.5-55.1%]. Significant pain alleviation and performance status improvement were obtained in 5 of 12 patients (41.7%; CI 13.8-69.6%) and 3 of 13 patients (23.1%; CI 0.2-46.0%), respectively. Although myelosuppression was moderate to severe, no chemotherapy-related deaths or bacteriologically documented sepsis occurred; nor was there any clinical cardiotoxicity. All the responding patients received maintenance chemotherapy with etoposide thereafter. At present, the median duration of response is 33 weeks (range: 23-91 weeks) and the median survival period for all patients is 42 weeks (range: 27(+)-136 weeks), with 12 deaths. In spite of the small number of patients treated, these results suggest that this chemotherapy regimen is active in advanced hormone-refractory prostate carcinoma.

Adenocarcinoma↗
PubMed1995

Ultraviolet action spectra for peroxide generation in human and pig epidermal keratinocytes loaded with dihydrorhodamine 123.

We developed a new and simple method for measuring peroxides in a single living cell, and the generation of peroxides upon ultraviolet (UV) irradiation was measured in human and pig epidermal keratinocytes. The method was based on the fact that the non-fluorescent dye, dihydrorhodamine 123, reacts in the presence of peroxides, such as H2O2, and changes into the fluorescent rhodamine 123, and hence the fluorescence intensity is proportional to the amount of reacted peroxide. The epidermal keratinocytes were loaded with the dihydrorhodamine under a fluorescence microscope and exposed to UV radiation. Taking C as the content of peroxides generated within the cell and I as the increase in fluence (radiation intensity x time = photons/cm2), the following empirical relationship was established: C = Cs (1-exp(-kI)), where Cs is the content of peroxides at the saturation state, and k is a kinetic parameter. The dependence of the two parameters on wavelength in the range 280-400 nm was studied. In human keratinocytes Cs had a peak at 310 nm and a small peak (shoulder) at 380 nm, while k increased gradually toward shorter wavelengths. In pig keratinocytes, on the other hand, k had a peak around 380 nm and a shoulder at 330 nm, while Cs remained unchanged. Aminotriazole, an inhibitor of catalase, and low temperatures increased the stationary levels of peroxide generation in pig keratinocytes upon UV irradiation, indicating that the reaction used for measuring intracellular peroxides is competitive with the intrinsic reactions in scavenging peroxides.

Amitrole↗
PubMed1995

Evaluation of portal circulation through the superior mesenteric vein with an enteric capsule of [123I]iodoamphetamine.

We report a method by which the contribution of the superior mesenteric vein to the portal blood flow can be evaluated noninvasively. An enteric-coated capsule containing [123I]iodoamphetamine is given by mouth 3h before the examination. The data obtained are treated by computer to calculate the portal shunt index (SI) through the superior mesenteric vein. The SI was higher for more severe liver disorders, Increasing in the order of chronic persistent hepatitis, chronic aggressive hepatitis, and cirrhosis. The SI was higher in cirrhotic patients than in chronic hepatitis patients or healthy volunteers (both, P < 0.0001). The SI was higher in cirrhotic patients with esophageal varices than in such patients without varices (P < 0.05). The SI was higher in cirrhotic patients with ascites than in such patients without ascites (P < 0.001). The SI was higher in cirrhotic patients with encephalopathy than in those without encephalopathy (P < 0.01). Correlation was significant between the SI and classical indicators of functional reserve. This method is clinically useful.

Administration, Oral↗
PubMed1995

Electron microscopic study of endogenous peroxidase activity in human liver macrophages.

We evaluated the conditions of fixation for ultrastructurally demonstrating the endogenous peroxidase (PO) activity of macrophages in biopsied human liver. The application of microwaving and immersion fixation with tannic acid and aldehydes allowed excellent visualization of PO activity in the nuclear envelope (NE), rough endoplasmic reticulum (rER), and cytoplasmic granules (CG), with good preservation of cellular ultrastructures. The macrophages with PO activity showed one of the following five patterns of PO localization: positive in both the NE and rER but negative in the CG (type 1); negative in both the NE and rER but positive in the CG (type 2); negative in the NE but positive in both the rER and CG (type 3); positive in all three (type 4); PO negative (type 5). The type 1 cells resembled typical Kupffer cells, type 2 cells monocytes, and type 3 and 4 cells the exudate-resident macrophages considered to be a transitional form between exudate and resident macrophages. Type 5 cells may also be a transitional form between the exudate and resident macrophage, or an end-stage macrophage derived from exudate macrophages which have lost their PO activity. Tannic-acid-aldehyde immersion fixation with microwaving may be a useful method in the study of the PO activities of macrophages in biopsied human liver specimens.

Cell Nucleus↗
PubMed1995

Mucinous cystadenoma of appendix concomitant with perityphlic granuloma.

We describe a case of mucinous cystadenoma of the appendix with perityphlic granuloma. The patient developed a hard palpable mass in the right lower quadrant and barium enema induced irregular bowel wall at the cecum. Based on a preoperative diagnosis of carcinoma of the appendix, we performed a laparotomy. On operation, we found a tumor mass in the region of the appendix; the mass adhered strongly to the retroperitoneum and cecum. Right hemicolectomy was carried out on a diagnosis of carcinoma of the appendix. Microscopic examination revealed mucinous cystadenoma of the appendix with perityphlic granuloma. Mucinous cystadenoma in the appendix is a rare tumor. In this patient, the tumor was accompanied by granuloma formation in adjacent tissues because of mucin expelled from the appendix. This case emphasizes that granuloma formation can make of difficult to differentiate mucinous cystadenoma in the appendix from cancer.

Appendiceal Neoplasms↗
PubMed1995

Biodiscrimination of alpha-tocopherol stereoisomers during intestinal absorption.

Synthetic alpha-tocopherol (alpha-Toc) contains equal amounts of eight different stereoisomers, and the four stereoisomers with the 2R configuration are generally more active than their corresponding 2S-isomers. We investigated the biodiscrimination of alpha-Toc stereoisomers during intestinal absorption in situ and in vitro. Intestinal absorption of alpha-Toc stereoisomers was examined in situ in vitamin E-deficient rats with cannulated thoracic ducts. We found that the ratios of alpha-Toc stereoisomers in lymph of the all-rac-alpha-Toc group were the same as the administered alpha-Toc stereoisomers, and 2R-isomers occupied approximately 50% of absorbed alpha-Toc. The uptake of alpha-Toc stereoisomers also was measured using Caco-2 cells cultured on filter membranes. The concentration of RRR-alpha-Toc in Caco-2 cells was not significantly different from that of SRR-alpha-Toc. Therefore, the discrimination of alpha-Toc stereoisomers does not occur during absorption in small intestine, suggesting the liver as source for the biodiscrimination.

Animals↗
PubMed1995

The effect of methylprednisolone on cisplatin-induced nephrotoxicity in rat renal cortical slices.

To investigate the protective action of methylprednisolone against cisplatin nephrotoxicity, the effect of in vivo pretreatment with methylprednisolone on the cisplatin-induced reduction in p-aminohippurate (PAH) accumulation and gluconeogenesis was examined using renal cortical slices prepared from Sprague-Dawley rats. The PAH accumulation in the kidney slices prepared from methylprednisolone-pretreated rats was significantly reduced following in vitro incubation with 2 mM cisplatin, to a degree equal to that observed in the slices prepared from untreated rats. However, the inhibitory effect of cisplatin on gluconeogenesis in the renal cortical slices obtained from methylprednisolone-pretreated rats was significantly smaller than that seen in the slices from untreated rats. Our present studies suggest that in vivo pretreatment with methylprednisolone may contribute to its protective effect against cisplatin nephrotoxicity through the process of gluconeogenesis in renal epithelial cells.

Animals↗
PubMed1995

Experimental assessment of newly devised transcatheter stent-graft for aortic dissection.

Despite recent advances, surgical results for Stanford type B dissection are not yet satisfactory because the procedure is so highly invasive. The aim of this study was to devise a new intraaortic (IA) graft that would offer less invasive treatment for type B dissection. To close the entry of type B dissections using transcatheter placement, we devised an IA graft (inner diameter, 15-20 mm; length, 40 to 60 mm) in which a self-expandable stent was covered with a thin, open-cell-structured polyurethane jacket. In acute animal experiments in which type B aortic dissections were prepared in 4 mongrel dogs, IA grafts were implanted to close the entry using a transfemoral catheter sheath, and closure of all the entries was confirmed by aortography. In chronic experiments, five IA grafts for normal descending aortas and one IA graft for an experimentally dissected aorta were implanted to observe histologic biocompatibility for up to 8 months. Histopathologic examination conducted at the projected sacrifice periods revealed that endothelialization of the luminal surface of the IA graft had begun as early as 1 month after implantation and was completed within 4 months. The prototype device that we developed may be promising as an effective, minimally invasive therapeutic intervention for closure of the entry site of type B dissection.

Aortic Dissection↗
PubMed1995

Polarized Raman spectra of oriented fibers of A DNA and B DNA: anisotropic and isotropic local Raman tensors of base and backbone vibrations.

Polarized Raman spectra of oriented fibers of calf thymus DNA in the A and B conformations have been obtained by use of a Raman microscope operating in the 180 degrees back-scattering geometry. The following polarized Raman intensities in the spectral interval 200-1800 cm-1 were measured with both 514.5 and 488.0 nm laser excitations: (1) Icc, in which the incident and scattered light are polarized parallel to the DNA helical axis (c axis); (2) Ibb, in which the incident and scattered light are polarized perpendicular to c; and (3) Ibc and Icb, in which the incident and scattered light are polarized in mutually perpendicular directions. High degrees of structural homogeneity and unidirectional orientation were confirmed for both the A and B form fibers, as judged by comparison of the observed Raman markers and intensity anisotropies with measurements reported previously for oligonucleotide single crystals of known three-dimensional structures. The fiber Raman anisotropies have been combined with solution Raman depolarization ratios to evaluate the local tensors corresponding to key conformation-sensitive Raman bands of the DNA bases and sugar-phosphate backbone. The present study yields novel vibrational assignments for both A DNA and BDNA conformers and also confirms many previously proposed Raman vibrational assignments. Among the significant new findings are the demonstration of complex patterns of A form and B form indicator bands in the spectral intervals 750-900 and 1050-1100 cm-1, the identification of highly anisotropic tensors corresponding to vibrations of base, deoxyribose, and phosphate moieties, and the determination of relatively isotropic Raman tensors for the symmetrical stretching mode of phosphodioxy groups in A and B DNA. The present fiber results provide a basis for exploitation of polarized Raman spectroscopy to determine DNA helix orientation as well as to probe specific nucleotide residue orientations in nucleoproteins, viruses, and other complex biological assemblies.

Animals↗