Search PubMed⌕ Search

Biomedical subjects

E Ueno

Publications and source records attributed to E Ueno.

At least 73 records · Page 4Linked to original sources
PubMed1992

Successful arterial embolization of arteriovenous fistula in the portal circulation.

We successfully performed arterial embolization of an arteriovenous fistula between the left gastric artery and vein. The increased blood flow in the portal vein via the left gastric vein and the arteriovenous fistula induced severe portal hypertension. After obliteration of the left gastric artery, the arteriovenous fistula was not opacified on angiography and the portal hypertension improved.

Arteriovenous Fistula↗
PubMed1992

Isolation and characterization of a Vicia graminea and Vicia unijuga lectins-binding (Vgu) glycoprotein with Thomsen-Friedenreich (T) activity from human liver metastases of pancreas carcinoma.

1. Perchloric acid-soluble fraction from liver metastases of pancreas carcinoma of a patient with blood group B, was subjected to a systematic affinity chromatography using Vicia unijuga lectin (VUA) and Arachis hypogaea anti-T lectin (PNA) as immobilized ligands and separated into three fractions, B-active glycoprotein fraction, serologically inactive glycoprotein fraction and glycoprotein (VP) fraction exhibiting reactivities for Vicia graminea lectin (VGA), VUA and PNA. 2. VGA- and VUA-binding (Vgu) glycoprotein with Thomsen-Friedenreich (T) activity which was isolated, in a high state of purity, from VP fraction by HPLC using Asahipak GS-710 column, was demonstrated to be a mannose-rich glycoprotein with mol. wt of 1492 kDa and contained 40.40% carbohydrate.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1992

Inhibition of phosphorylation of synapsin I and other synaptosomal proteins by beta-bungarotoxin, a phospholipase A2 neurotoxin.

Some snake venom neurotoxins, such as beta-bungarotoxin (beta-BuTX), which possess relatively low phospholipase A2 (PLA2) activity, act presynaptically to alter acetylcholine (ACh) release both in the periphery and in the CNS. In investigating the mechanism of this action, we found that beta-BuTX (5 and 15 nM) inhibited phosphorylation, in both resting and depolarized synaptosomes, of a wide range of proteins, including synapsin I. Naja naja atra PLA2, which has higher PLA2 activity, also inhibited phosphorylation but was less potent than beta-BuTX. At 1 nM, beta-BuTX and N. n. atra PLA2 inhibited phosphorylation of synapsin I only in depolarized synaptosomes. Synaptosomal ATP levels were not affected by 5 or 15 nM beta-BuTX or by 5 nM N. n. atra PLA2. Limited proteolysis, using Staphylococcus aureus V-8 protease, indicated that beta-BuTX inhibited phosphorylation of synapsin I in both the head and the tail regions. The inhibition of phosphorylation was not antagonized by nordihydroguaiaretic acid or indomethacin, suggesting that arachidonic acid derivatives do not mediate this inhibition. Furthermore, inhibition of phosphorylation by beta-BuTX and N. n. atra PLA2 was not altered in the presence of the phosphatase inhibitor okadaic acid, suggesting that stimulation of phosphatase activity is not responsible for this inhibition. Inhibition of protein phosphorylation by PLA2 neurotoxins and enzymes may be associated with an inhibition of ACh release.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1992

Hemodynamic effects of cilostazol on peripheral artery in patients with diabetic neuropathy.

On the basis of vascular involvement, an open clinical trial was performed to determine whether or not the antithrombotic drug cilostazol (6-[4-(1-cyclohexyl-1H-tetrazol-5-yl) butoxy]-3,4-dihydro-2(1H)-quinolinone, OPC-13013, Pletaal, CAS 73963-72-1) applied as a single 100 mg tablet increases peripheral blood flow and prevents diabetic neuropathy in 30 patients with non-insulin dependent diabetes mellitus. The hemodynamic effects of this drug on the a. dorsalis pedis were examined using a new real-time two-dimensional Doppler echography. 1 h after oral administration of cilostazol, the cross-sectional area of the a. dorsalis pedis significantly increased from 2.2 +/- 0.2 to 2.9 +/- 0.3 mm2 (p less than 0.05). Also, the a. dorsalis pedis blood flow index significantly increased from 16 +/- 1 to 31 +/- 4 (p less than 0.05). Cilostazol did not affect plasma glucose level (from 213 +/- 14 to 198 +/- 15 mg/dl), but slightly plasma ratio of 6-keto PGF1a to TXB2 (from 0.71 +/- 0.09 to 0.83 +/- 0.12). These effects of cilostazol might ameliorate diabetic neuropathy by improving blood flow and preventing nerve tissue ischemia.

6-Ketoprostaglandin F1 alpha↗
PubMed1990

Inhibition of phosphorylation of rat synaptosomal proteins by snake venom phospholipase A2 neurotoxins (beta-bungarotoxin, notexin) and enzymes (Naja naja atra, Naja nigricollis).

Some snake venom neurotoxins, such as beta-bungarotoxin (beta-BuTX) and notexin, which inhibit the release of neurotransmitter at both peripheral and central presynaptic terminals possess phospholipase A2 activity. In contrast, most snake venom phospholipase A2 enzymes such as those isolated from Naja naja atra and Naja nigricollis are structurally homologous to these neutrotoxins but do not have any specific or potent presynaptic action although they have higher enzymatic activities than the neurotoxins. In order to investigate the mechanisms of presynaptic action of the snake venom neurotoxins, we studied their effects on phosphorylation of rat brain synaptosomal proteins. It is known that phosphorylation of synapsin I, a neuron specific and synaptic vesicle associated phosphoprotein, increases neurotransmitter release. Incubation of cerebral cortical synaptosomes with 32P-orthophosphate at 37 degrees C for 30 min, caused significant phosphorylation of a wide mol. wt range of proteins including most markedly those proteins in the mol. wt range (81,000-86,000) of synapsin I. Both snake venom phospholipase A2 neurotoxins and enzymes (5, 15 and 50 nM) inhibited phosphorylation in a Ca2(+)-dependent manner with the following order of potencies: beta-BuTX greater than N.n. atra phospholipase A2 greater than or equal to notexin greater than N. nigricollis phospholipase A2. Five nanomoles of beta-BuTX, which has the lowest phospholipase A2 activity, inhibited phosphorylation of a wide range of mol. wt proteins (51,000-188,000) by 42-58%. At the same concentration, N.n. atra phospholipase A2 (which possesses the highest enzymatic activity), notexin and N. nigricollis phospholipase A2 caused less inhibition than beta-BuTX, ranging from 0-40% depending on the agent used. These results indicate that there is no correlation between their potencies in inhibiting phosphorylation and the levels of their phospholipase A2 activities. An inhibitory activity on phosphorylation may be at least partially responsible for a presynaptically-induced block of neurotransmitter release.

Animals↗
PubMed1990

Ultrasonically guided biopsy of nonpalpable lesions of the breast by the spot method.

A new biopsy method by injecting dye under ultrasonic guidance is most efficient and accurate for nonpalpable lesions revealed by ultrasonography. It can also minimize the amount of tissue that is resected. The conventional method by needle-wire localization has to be used in instances of calcification which cannot be defined by ultrasonography.

Adult↗
PubMed1989

Stabilisation of cathepsin E by ATP.

The hydrolysis of 3 distinct substrates by cathepsin E from human red blood cells and gastric mucosa was measured in the presence and absence of physiologically relevant concentrations of ATP. At pH values below about 5.0, the nucleotide was without effect. However, at pH 5.8, whereas cathepsin E was virtually inactive by itself, it was restored to full activity (kcat) by ATP and the non-hydrolysable methylene-ATP analogue. At still higher pH values, kcat progressively diminished but significant levels of cathepsin E activity were readily detectable at pH 7.0. The specificity of this stabilisation effect was examined.

Adenosine Triphosphate↗
PubMed1989

A case of metastasis from gastric cancer to the thyroid gland.

Metastatic tumors in the thyroid gland are rarely seen in clinical practice. This report describes a case of metastasis from gastric cancer to the thyroid, found five years after removal of the primary gastric lesion. The patient had a large thyroid mass extending to the mediastinum, but there were no obvious metastatic lesions anywhere except in the thyroid. Subtotal thyroidectomy was performed and histological examination revealed the same findings a those of the original gastric cancer. Of additional interest are the findings that led us to believe this metastatic tumor produced alpha-fetoprotein. Seven months following the operation, the patient dies suddenly and, although it is difficult to say whether the patient's survival was prolonged, we believe that the thyroid surgery gene him considerable palliation.

Adenocarcinoma↗
PubMed1989

Activation mechanism of erythrocyte cathepsin E. evidence for the occurrence of the membrane-associated active enzyme.

Activation of the erythrocyte cathepsin E located on the cytoplasmic surface of the membrane in a latent form was studied in stripped inside-out membrane vesicles prepared from human erythrocyte membranes. Incubation of the vesicles at 40 degrees C at pH 4 resulted in increased degradation of the membrane proteins, especially band 3. This proteolysis was selectively inhibited by the inclusion of pepstatin (isovaleryl-Val-Val-statyl-Ala-statine) or H 297 [Pro-Thr-Glu-Phe(CH2-NH)Nle-Arg-Leu] in the incubation mixtures, indicating that cathepsin E, as the only aspartic proteinase in erythrocytes, is responsible for the proteolysis. Two potential active-site-directed inhibitors of aspartic proteinases, pepstatin and H 297, were used to prove the occurrence of the membrane-associated active enzyme. To minimize potential errors arising from non-specific binding, the concentrations of the inhibitors used in the binding assay (pepstatin, 5 x 10(-8) M; H 297, 1 x 10(-5) M) were determined by calibration for purified and membrane-associated cathepsin E. The inhibition of the membrane-associated cathepsin E by each inhibitor, which showed the binding of the inhibitor to the activated enzyme, was temperature- and time-dependent. The binding of each inhibitor to the enzyme on the exposed surface of the membrane at pH 4 was highly specific, saturable, and reversible. The present study thus provides the first evidence that cathepsin E tightly bound to the membrane is converted to the active enzyme in the membrane-associated form, and suggests that this enzyme may be responsible for the degradation of band 3.

Biotransformation↗
PubMed1989

[Localization of pancreatic insulinomas by combined radiographic methods].

Seventeen cases with a total of eighteen insulinomas were examined by ultrasonography (US), computed tomography (CT), angiography, percutaneous transhepatic portal and pancreatic venous sampling (PTPS) and intraoperative ultrasonography (IOUS). We discussed about diagnostic accuracy of insulinomas on these diagnostic modalities. Tumor localization was achieved by US in 39%, CT in 72% and angiography in 81%. Although total 15 tumors (83%) can be correctly detected, multiple lesions were not completely ruled out. We recommended the criteria in PTPS as follows: Insulin concentration level above 200 mu U/ml. Or, both of insulin concentration ratio (step-up site/control) above three and elevation of the CPR concentration level on the PTPS. According to these criteria, the accuracy rate was 91%. Overall preoperative diagnostic accuracy was 100%. IOUS allowed us to detect the localization of the tumors completely.

Adenoma, Islet Cell↗
PubMed1989

Evaluation of dot-immunobinding assay for carcinoembryonic antigen determination in nipple discharge as an adjunct in the diagnosis of early breast cancer. Research Group for Carcinoembryonic Antigen in Nipple Discharge.

We have previously reported carcinoembryonic antigen (CEA) measurement in nipple discharge to be a useful adjunct in the diagnosis of non-palpable breast cancer. As an extension, a dot-immunobinding assay was developed to screen a large number of patients with nipple discharge for non-palpable breast cancer. The principle is as follows. CEA bound to a solid phase monoclonal anti-CEA antibody is detected by a second monoclonal anti-CEA antibody conjugated with horseradish peroxidase. The use of tetramethylbenzidine as a chromogen results in a stable color reaction that can be semiquantitively analyzed by the naked eye. The CEA levels determined by this dot assay correlated well with CEA levels determined using the former Elmotec assay. To determine whether or not the method could also be feasible in the detection of non-palpable breast cancer, a collaborative study from 12 Japanese institutes was organized. The CEA levels in nipple discharges from 155 patients were assayed. Thirteen of 30 patients with palpable breast cancer and 22 of 30 patients with non-palpable breast cancer exhibited CEA values higher than 400 ng/ml, a cut-off value determined using 89 benign controls. The specificity (91%) and sensitivity (73%) of this test were higher than those of mammography or cytology. The incidence of elevated CEA levels in nipple discharge correlated significantly with the incidence of intratumoral antigen expression. Thus, the system could prove useful in screening for early breast cancer.

Body Fluids↗
PubMed1989

[Clinical and physiological study of apraxia of gait and frozen gait].

A study of clinical features and an analysis of gait with floor reaction forces and EMG of leg flexors and extensors were made in patients with multiple cerebral infarction or patients with Parkinson's disease having frozen gait. A case with occlusion of the bilateral anterior cerebral arteries resulting in massive infarction of the infero-medial part of the frontal lobes was also studied as he showed a unique disorder characterized by apraxia of gait. Frozen gait is characterized by shuffling steps, broad-based stance, positive foot grasp, kinesia paradoxa and disturbance of postural reflexes. The vector angle which shows foot pressure in forward locomotion was decreased in patients with frozen gait. EMGs of lower leg muscles in frozen gait were grouping of potentials corresponding to the shuffle and reciprocity between flexors and extensors was preserved. The patient with infarction of the bilateral anterior cerebral arteries showed a peculiar disorder of gait which was characterized by an inability to initiate stepping. It is considered as "apraxia of gait" in a classical sense, which differs from frozen gait. Observation of this patient suggests that the infero-medical part of the frontal lobe plays an important role in the initiation of gait. Furthermore, common features of frozen gait in patients with Parkinson's disease and in patients with multiple cerebral infarction involving the frontal lobe suggest that the nigrostriatal structures and the frontal lobe are important in CNS mechanisms subserving smooth locomotion.

Aged↗