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S Ueda

Publications and source records attributed to S Ueda.

At least 487 records · Page 27Linked to original sources

A clinicopathological analysis of early gastric cancer: retrospective study with special reference to lymph node metastasis.

We reviewed 217 cases of early gastric cancer (EGC) resected from 1978 through 1988. To determine the indications for curative resection by endoscopic mucosectomy (EM) for EGC, we paid special attention to lymph node metastasis examined after gastrectomy. The overall incidence of lymph node metastasis was 12.4%. It was 3.4% for mucosal (m-) cancer and 23.5% for submucosal (sm-) cancer. The maximum diameter of the lesion, depth of cancerous invasion, and location of the lesion showed positive correlations with lymph node involvement (p < 0.05). EGCs less than 20 mm in diameter had no lymph node metastasis. Pieces of mucosa about 20 mm in diameter on the average could be obtained with a single EM procedure. EGC with ulceration had a higher incidence of lymph node involvement than did that without ulceration. We conclude that if EM reveals an intramucosal gastric carcinoma less than 20 mm in diameter without ulceration, curative resection by EM is indicated.

Adenocarcinoma↗

[Effect of amurinone on human pulmonary artery in vitro].

We studied the effect of amurinone, a phosphodiesterase inhibitor, on human pulmonary arterial smooth muscle in vitro. Amurinone caused dose-dependent relaxation of pulmonary arterial strips precontracted with 60 mM KCl. Preincubation with either meclofenamate (31 microM), a cyclooxygenase inhibitor, or L-NG-nitroarginine (100 microM), an endothelium-derived relaxing factor (EDRF) production inhibitor, failed to inhibit amurinone-induced pulmonary vasodilation. The cyclic AMP (cAMP) levels in the supernatant of the lung vessel homogenates significantly increased after incubation with amurinone. These results indicate that amurinone causes relaxation of human pulmonary artery in vitro, and suggest a role for cAMP in the mechanisms of amurinone-induced pulmonary vasodilation.

Adult↗

Pharmacokinetic profiles of intravenous imipenem/cilastatin during slow hemodialysis in critically ill patients.

The pharmacokinetics of imipenem/cilastatin were determined in 7 critically ill patients undergoing slow hemodialysis (HD). All patients were anuric. Following intravenous administration of 500 mg of imipenem/cilastatin, concentrations of the drugs in the serum and dialysate were monitored during slow HD. The elimination phase half-life of imipenem was 3.1 +/- 0.3 h and that of cilastatin was 9.7 +/- 1.2 h. The total body clearance of imipenem and cilastatin was 84.0 +/- 7.2 and 32.2 +/- 2.4 ml/min, respectively. Clearance of imipenem and cilastatin during slow HD was 24.3 +/- 2.4 and 54.3 +/- 3.1%, respectively, of total body clearance. After the 10.5-h session of slow HD, serum concentrations of imipenem and cilastatin were 2.3 +/- 0.4 and 16.0 +/- 1.2 mg/l, respectively. It appears that at least 500 mg of imipenem may be needed as a supplemental dose after a session of slow HD or the application interval should be shortened to maintain a therapeutic concentration.

Aged↗

Regeneration of serotonergic immunoreactive fibers in the brain of 5,6-dihydroxytryptamine treated rat.

After the intraventricular injection of 5,6-dihydroxytryptamine (5,6-DHT), the course of degeneration and regeneration of the serotonergic fibers in the rat brain was studied immunohistochemically by using serotonin antiserum. Three days after 5,6-DHT treatment, an extensive disappearance of serotonin immunoreactive fibers was observed throughout the brain. Degenerative serotonergic fibers characterized by droplet-like swelling and intense staining by serotonin antiserum were detected in the following discrete areas, e.g., medial forebrain bundle (MFB), cingulate cortex, septal nucleus, diagonal band of Broca (DBB), lateral preoptic area, bed nucleus of stria terminalis, perifornical area, stria-terminals, raphe nuclei, ventral tegmental area, periaqueductal gray lateral reticular nucleus and nucleus of the solitary tract. The swelling were regarded as the proximal stumps of the chemically injured serotonin fibers. Sprouting serotonin fibers emanating from these swellings were observed 5 days after injection. The swollen thick fibers were seen up to 3 months thereafter throughout the brain, although they gradually decreased in number until 1 month after injection. On the contrary, the sprouting fibers extended their terminal fields throughout the brain. Three types of reorganization pattern of regenerating serotonergic fibers were distinguished: hyperinnervation, normoinnervation (similar to the normal innervation) and hypoinnervation patterns. In the areas with hyperinnervation, the density of the serotonergic fibers gradually increased for 3 months. These hyperinnervation patterns of regenerative serotonergic fibers were observed in the MFB, cingulate cortex, diagonal band of Broca, perifornical area, raphe nuclei, ventral tegmental area, motor trigeminal nucleus, facial nucleus, lateral reticular nucleus, inferior olivary complex and hypoglossal nucleus. On the other hand, the hypoinnervation displayed by a few regenerating serotonergic fibers was observed in the periventricular part of the prosencephalon, the ventromedial part of the hypothalamus, the dorsal hippocampus, the neocortex, the superior and inferior colliculi, the cerebellum, the dorsal tegmental nucleus of Gudden, the vestibular nuclei, the gracile nucleus and the cuneate nucleus. These reorganization patterns were formed 3 months after injection, and continued for a long time (2 years). The mechanisms of serotonergic fiber reorganization are discussed.

5,6-Dihydroxytryptamine↗

[Lung 3H-thymidine incorporation in monocrotaline (MCT)-treated rats--role of platelet-activating factor (PAF)].

Monocrotaline (MCT) causes chronic pulmonary hypertension associated with pulmonary vascular thickening in rats. Since components of the pulmonary vascular thickening are reflected in increased DNA synthesis in medial smooth muscle cells, and since platelet-activating factor (PAF) has been reported to contribute to the pulmonary hypertension induced by MCT, we examined the effect of WEB 2170, a specific PAF receptor blocker, on MCT-induced pulmonary vascular thickening and in vitro 3H-thymidine incorporation into lung tissue, as an index of stimulation of cell proliferation. In MCT-treated rats, pulmonary hypertension, right ventricular hypertrophy, and pulmonary vascular thickening developed at 3 weeks after injection. Also, in MCT-treated rat lung tissue, there was a significant increase in the in vitro 3H-thymidine incorporation rate. In WEB 2170-treated MCT rats, these changes were significantly less severe than those observed in rats receiving MCT alone. We conclude that PAF plays a role in the inflammatory process that contributes to the development of pulmonary hypertension and vascular remodeling associated with increased lung cell proliferation in MCT-treated rats.

Animals↗

[A case of lung cancer combined with ocular myopathy and idiopathic thrombocytopenic purpura which was presumed to be caused by heart catheterization].

A 61-year-old patient was admitted to our hospital because of a chest abnormal shadow. He was suffered from ocular myopathy for more than 4 years. A lab data on the admission showed only a slight thrombocytopenia. After the unilateral pulmonary arterial occlusion test for the preoperative evaluation of thoracotomy, the hemorrhagic tendency was appeared. A detailed examination proved idiopathic thrombocytopenic purpura which was presumed to be caused by the heart catheterization. We employed high-dose intravenous gamma-globulin infusion and concentrated platelet transfusion for 5 days for preventing hemorrhagic complications during the thoracotomy. The partial resection was undergone for the left upper lobe tumor, which was proved as large cell carcinoma. The postoperative hemorrhage was well controlled. We conclude that the high-dose intravenous gamma-globulin infusion and/or concentrated platelets transfusion should be positively employed for the patients with even slight thrombocytopenic purpura.

Carcinoma, Non-Small-Cell Lung↗

Carnitine determination by an enzymatic cycling method with carnitine dehydrogenase.

We describe a highly sensitive and specific method for determining L-carnitine in serum by use of carnitine dehydrogenase (EC 1.1.1.108). The method involves a new enzymatic cycling technique with NADH, thio-NAD+, and carnitine dehydrogenase, and measures the increase of absorbance at 415 nm of thio-NADH produced at 37 degrees C during the reaction: [formula: see text] The calibration curve for L-carnitine in serum was linear between 5 and 250 mumol/L. Analytical recovery was 96.5-106%, and within-run and between-run imprecisions (CV) were 0.66-4.33% and 1.02-2.56%, respectively. This method was free from interference by bilirubin, hemoglobin, various acyl-DL-carnitines, and ascorbate. The procedure is simple, rapid, accurate, and automatable. The amount of free L-carnitine in serum (53.6 +/- 11.7 mumol/L, n = 200) was greater in men than in women (45.1 +/- 14.2 mumol/L, n = 200) (mean +/- SD).

Alcaligenes↗

Vascular response to vasoactive agents in dialysed patients with chronic renal failure with and without diabetes mellitus.

Using a muscle bath technique the vascular response to KCl, noradrenaline, angiotensin II, acetylcholine, and sodium nitroprusside were evaluated in 13 patients with diabetes mellitus (DM group) and 15 nondiabetic (non-DM group) chronic renal failure patients treated with haemodialysis. There were no differences in age, duration of haemodialysis, blood pressure and the levels of plasma renin activity, noradrenaline, and parathyroid hormone between groups. After informed consent was obtained, a small piece of forearm vein was resected during the blood access surgery. The ring preparation of the blood vessel was sustained in the muscle bath filled with Krebs-Henseleit solution and the isometric tension development was recorded. All drugs produced concentration dependent responses in the ring preparations of both groups. Although there were no significant differences in Emax values for KCl- and angiotensin-II-induced contractions between groups, the value for noradrenaline in the DM group was significantly less than that in the non-DM group. Sodium nitroprusside completely relaxed the ring preparation precontracted by 10(-5) M noradrenaline. However, the response to acetylcholine in the DM group was significantly weaker than that in the non-DM group. These results suggest a reduced vascular response to noradrenaline and acetylcholine in dialysed diabetic renal failure patients, which may relate to the autonomic nervous system dysfunction.

Adult↗

[Clinical evaluation of endoscopic variceal ligation (EVL)].

From August 1992 through February 1993, we treated 21 patients with endoscopic variceal ligation (EVL). Two patients had a history of the esophageal variceal bleeding, but 19 patients did not have bleeding episodes. To evaluate preventive effect of bleeding, we selected the patients who had grade F2 or red color sign positive varices. We repeated EVL until varices improved into grade F0 or F1 and red color sign negative. The therapeutic goal was sometimes changed according to patient's general condition. No additional therapy was performed to eradicate varices, such as endoscopic injection sclerotherapy. As a result of our therapy, eradication rate was 73.7% and period of hospitalization were 25 +/- 11 days. No major complications were found during and after EVL. EVL affected neither liver function test nor size of gastric varices. Recurrent varices with red color sign were found in 4 patients, but easily controlled by retreatment with EVL. EVL seems to be convenient and effective therapy in our short-term study, and useful for preventive therapy of the esophageal variceal bleeding.

Aged↗

The phospholipase-A2 reaction leads to increased monocyte adhesion of endothelial cells via the expression of adhesion molecules.

Mononuclear cell invasion into the vascular-vessel wall is a very important initial step in the development of atherosclerotic lesions. Hypercholesterolemia leads to a marked adhesion of circulating blood monocytes to arterial endothelial cells in vivo, and minimally oxidized low-density lipoprotein enhances monocyte adhesion to endothelial cells in vitro. The activation of phospholipase A2 (PLA2) is also important in the oxidation of low-density lipoprotein by endothelial cells. In this study, we investigated the role of PLA2 activation in the adhesion of a leukemic monocyte cell line (THP-1 cells) to endothelial cells in vitro using an adhesion assay and a cell-ELISA technique. The treatment of human umbilical-cord-vein endothelial cells with PLA2 stimulators such as interleukin-1 beta, tumor necrosis factor and lipopolysaccharide all increased the adhesion of THP-1 cells to endothelial cells. Exogenous PLA2 also increased the adhesion of these cell types. The increased adhesion induced by these PLA2 stimulators, as well as PLA2 itself, was reversed by various inhibitors of the PLA2 reaction. A product of the PLA2 reaction, lysophosphatidylcholine, also increased cell adhesion. A cell-ELISA technique showed the enhanced expression of vascular-cell-adhesion-molecule 1 and intercellular-adhesion-molecule 1 to endothelial cells after treatment with PLA2 stimulators, PLA2 or lysophosphatidylcholine. These results suggest that the PLA2 reaction enhances monocyte adhesion to endothelial cells through the expression of cellular adhesion molecules.

Cell Adhesion↗

Increased heterogeneity of tyrosine hydroxylase in humans.

Humans produce four different forms of tyrosine hydroxylase (TH) mRNA via alternative splicing of the gene. Here we demonstrate that New- and Old-World monkeys and the gorilla produce only two of the TH isoforms. Comparison among the genomic DNA sequences of various primates revealed that mutations that had accumulated in the genomic DNA created a new exon, resulting in the appearance of two new TH isoforms in man. These findings offer new insight into the sequence of events leading to the evolution of the higher primates into separate species. They also represent what may be the first evidence of a genetic difference between man and primates with respect to a specific brain function.

Animals↗

Cloning and expression of a Pseudomonas 3 alpha-hydroxysteroid dehydrogenase-encoding gene in Escherichia coli.

A bacterial strain, B-0831, which produced 3 alpha-hydroxysteroid dehydrogenase (3 alpha HSD) was isolated and identified as belonging to the genus, Pseudomonas. Molecular weights of the purified 3 alpha HSD, determined by SDS-PAGE and by chromatography on Sephacryl S-200, were about 25 and 50 kDa, respectively. A genomic library of Pseudomonas sp. B-0831, prepared in the plasmid vector pACYC184, was screened with probes based on the amino acid (aa) sequence of the protein to obtain the plasmid, p3 alpha HSD1, identified by hybridization with the probes, that contained a 2.4-kb insert from Pseudomonas DNA. When the 1.4-kb SphI fragment of p3 alpha HSD1 was inserted into the vector, pUC118, and introduced into Escherichia coli DH1 under the control of lacZ promoter in the vector, the transformants produced 200-fold more 3 alpha HSD intracellularly than Pseudomonas sp. B-0831. Sequence analysis of the 3 alpha HSD gene revealed that an ORF encoding 3 alpha HSD consists of 254 aa, with a calculated M(r) of 25,761, suggesting that the enzyme consists of homodimer subunits.

3-Hydroxysteroid Dehydrogenases↗

[The histochemical study of the effects of estrogen on the forebrain cholinergic neurons of fetal female rats transplanted into the anterior eye chamber of adult female rats].

In order to clarify the effects of estrogen on cholinergic basal forebrain neurons, a cholinergic neuron in the diagonal band nucleus of the female fetal rat was implanted into the anterior eye chamber of the female adult rat. Some host rats were treated with 2mg estradiol valerate (E2v) injected every 3 days after ovariectomy while others were not 2 and 4 weeks after transplantation, the growth of cholinergic neurons in the graft was studied using acethylcholinesterase (AChE) histochemistry. At 2 weeks after transplantation, AChE positive neurons and fibers were densely distributed in the grafts of E2v treated rats. Also in grafts without E2v treatment, AChE positive neurons and fibers were found in all the grafts although their density was low. At 4 weeks, AChE staining was dense staining observed in both groups. These results indicate that neurotrophic effect of estrogen on the cholinergic basal forebrain neurons.

Acetylcholinesterase↗

Intraocular co-grafts of fetal dorsal raphe nucleus and suprachiasmatic nucleus.

Serotonergic neurons in the fetal dorsal raphe nucleus were grafted together with fetal anterior hypothalamic tissue including the suprachiasmatic nucleus (SCN) to the anterior eye chamber of adult rats. After 6 weeks transplantation, the double grafts were immunocytochemically examined using antisera against serotonin, arginine vasopressin (AVP) and vasoactive intestinal polypeptide (VIP). The raphe grafts contained a large number of serotonin-immunoreactive neurons and fibers, but only a few AVP-immunoreactive fibers and VIP-immunoreactive neurons and fibers. On the other hand, numerous AVP- and VIP-immunoreactive neurons and fibers were found in the SCN of the anterior hypothalamic graft. Outgrowing serotonin-immunoreactive fibers from the raphe tissue were densely distributed in the anterior hypothalamic graft. In the SCN, however, only a few fibers were detected. The results demonstrate that the isolated anterior hypothalamic grafts can be innervated by the serotonergic neurons from the raphe grafts, but the innervation pattern of these fibers was quite different from the normal rat. The present results indicate that the isolated SCN has an inhibitory influence on the growth of serotonergic fibers.

Animals↗

Antagonistic action of imidazolineoxyl N-oxides against endothelium-derived relaxing factor/.NO through a radical reaction.

A labile inorganic free radical, nitric oxide (.NO), is produced by nitric oxide synthase from the substrate L-arginine in various cells and tissues. It acts as an endothelium-derived relaxing factor (EDRF) or as a neurotransmitter in vivo. We investigated the reactivity of stable radical compounds, imidazolineoxyl N-oxides such as 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO), carboxy-PTIO, and carboxymethoxy-PTIO against .NO/EDRF in both chemical and biological systems. By using electron spin resonance (ESR) spectroscopy, imidazolineoxyl N-oxides were found to react with .NO in a stoichiometric manner (PTIO/.NO = 1.0) in a neutral solution (sodium phosphate buffer, pH 7.4) with rate constants of approximately 10(4) M-1 s-1, resulting in the generation of NO2-/NO3- and imidazolineoxyls such as 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl (PTI), carboxy-PTI, or carboxymethoxy-PTI. Furthermore, the effects of imidazolineoxyl N-oxides on acetylcholine- or ATP-induced relaxation of the smooth muscle of rabbit aorta were tested. The vasorelaxations were inhibited by all three imidazolineoxyl N-oxides markedly. The inhibitory effects of carboxy-PTIO was almost 2-fold stronger than those of .NO synthesis inhibitors, N omega-nitro-L-arginine and N omega-monomethyl-L-arginine. Generation of EDRF/.NO was identified by reacting the PTIO in aortic strips and quantitating the reaction product with ESR spectroscopy. Thus, it was clarified that imidazolineoxyl N-oxide antagonize EDRF/.NO via a unique radical-radical reaction with .NO.

Acetylcholine↗