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Biomedical subjects

S Tsuji

Publications and source records attributed to S Tsuji.

At least 613 records · Page 34Linked to original sources
PubMed1994

Typical fibrolamellar hepatocellular carcinoma in Japanese patients: report of two cases.

We report herein the cases of two Japanese patients with typical fibrolamellar hepatocellular carcinoma treated at our institute. The first patient was a 19-year-old man with no hepatitis B or C viral infection and a normal, noncirrhotic liver in the nontumorous area. The second was a 36-year-old woman with no viral infection and a noncirrhotic liver in the nontumorous area. The clinicopathology, imaging appearances, and histology of both cases were similar to reports from the United States.

Adult↗
PubMed1994

Impaired gastric mucosal energy metabolism in congestive gastropathy in cirrhotic patients.

To clarify the characteristics of congestive gastropathy, we investigated gastric mucosal hemodynamics and energy metabolism in cirrhotic patients, using a reflectance spectrophotometry system and high performance liquid chromatography. The index of the gastric mucosal blood volume of cirrhotic patients with esophageal varices was significantly higher, and the index of gastric mucosal blood oxygenation significantly lower, than those in controls, thus indicating congestion and hypoxia in the gastric mucosa. Energy charge levels in the gastric mucosa of cirrhotic patients with esophageal varices were also significantly decreased. The energy charge level showed a strong linear correlation with the index of mucosal blood oxygenation in the antral (r = 0.996, P < 0.01) and body (r = 0.994, P < 0.01) mucosa of the stomach. These findings suggest that congestive gastropathy in a portal hypertensive state causes hypoxia in the gastric mucosa, leading to a mucosal energy deficit that may increase mucosal susceptibility to aggressive factors.

Chromatography, High Pressure Liquid↗
PubMed1994

Role of endothelin 1 in hemorrhagic shock-induced gastric mucosal injury in rats.

BACKGROUND/AIMS: Gastric microcirculatory disturbances are involved in the pathogenesis of stress ulcers; however, vasomodulators regulating this process are not fully understood. This study was conducted to investigate the role of endothelin 1 (ET-1) in hemorrhagic shock-induced gastric mucosal damage in rats. METHODS: ET-1 contents in plasma and gastric mucosa were measured and gastric mucosal damage was evaluated during a control period, 60 minutes of ischemia, 15 minutes of reperfusion, and 30 minutes of postreperfusion. Next, effects of BQ-123, an endothelinA receptor antagonist, on the gastric mucosal damage and hemodynamics were studied. RESULTS: Both plasma and mucosal ET-1 significantly increased after ischemia and reperfusion compared with the control values, but only mucosal ET-1 continued to increase after reperfusion, leading to the development of gastric mucosal damage. BQ-123, administered just before reperfusion, reduced mucosal damage in the postreperfusion period dose-dependently and improved mean gastric mucosal blood flow and mucosal hemoglobin oxygen saturation during the 30-minute postreperfusion period. CONCLUSIONS: These results suggest that endogenous ET-1 plays an important role in the pathogenesis of hemorrhage shock-induced gastric mucosal damage through impairment of mucosal microcirculation. Further, endothelinA antagonists may have therapeutic benefits for shock-induced gastric mucosal damage.

Animals↗
PubMed1994

Comparison of benzodiazepine receptor and regional cerebral blood flow imaging of epileptiform foci in hippocampal kindled rabbits: a preliminary report.

To clarify experimentally which of benzodiazepine (BZ) receptor or regional cerebral blood flow (rCBF) imaging is more sensitive in the detection of epileptic foci, we simultaneously examined the BZ receptor and rCBF distribution changes in hippocampal kindled rabbits with in vivo double tracer autoradiography using 125I-labeled Ro 16-0154 (125I-Iomazenil) and 99mTc-labeled hexamethyl-propyleneamine oxime (99mTc-HMPAO). In visual analysis of brain slices extracted after the intravenous injection of the double tracer following the kindling completion, 125I-Iomazenil accumulation was more markedly and extensively decreased in the kindled right CA1 region mimicking a primary epileptic focus than 99mTc-HMPAO accumulation. Further, this decrease in 125I-Iomazenil accumulation was not due to neuropathological abnormalities which consisted only of tissue damage corresponding to electrode track in the right CA1. These results suggest that BZ receptor imaging is more sensitive in the detection of epileptic foci than rCBF imaging and, therefore, that BZ receptor imaging is useful in clinical epilepsy.

Animals↗
PubMed1994

Vasoactive effect of endothelin-1 on rat liver in vivo.

The purpose of this study was to evaluate the role of endothelin-1 in modulating hepatic microcirculation and liver damage. Rats were infused with endothelin-1 at doses ranging from 30 to 1,000 pmol/kg over 1 min through an indwelling cannula placed in the portal vein. In control rats, saline solution was infused at the same rate. Alterations in hepatic microcirculation were measured with an in vivo microscopy system. Serum lactate dehydrogenase activity, an indicator of hepatic damage, was measured 1 hr after endothelin-1 infusion. Immediately after infusion of endothelin-1, we noted a rapid increase in portal pressure, which remained increased for up to 30 min after endothelin-1 infusion. In contrast, systemic blood pressure remained unchanged, even at 1,000 pmol/kg of endothelin-1. Sinusoidal width was reduced and sinusoidal erythrocyte velocity was diminished in a dose-dependent manner. Oxygen saturation of blood in sinusoids was decreased in a dose-dependent manner, reaching values around 40% of control with 1,000 pmol/kg endothelin-1. The degree of decrease in oxygen saturation of blood in sinusoids had an excellent correlation with the calculated blood flow in the liver tissue. Serum lactate dehydrogenase levels were three to four times control values when endothelin-1 was administered at 1,000 pmol/kg. Thus endothelin-1 decreased hepatic tissue oxygenation associated with sinusoidal vasoconstriction. At high concentrations of endothelin-1, this decrease results in hepatocellular damage.

Animals↗
PubMed1994

Expression of mouse Gal beta 1,4GlcNAc alpha 2,6-sialyltransferase in an insoluble form in Escherichia coli and partial renaturation.

Mouse Gal beta 1,4GlcNAc alpha 2,6-sialyltransferase was produced in an insoluble form in Escherichia coli cells harboring expression plasmids. The insoluble protein was solubilized with 8 M urea and diluted for renaturation of the enzyme. The substrate specificity and kinetic parameters, except for the specific activity, of the renatured enzyme were similar to those of the enzyme obtained from rat liver. These results suggest that a bacterial expression system is a potentially powerful tool for the large scale production of sialyltransferases and for elucidating the molecular mechanisms of sialyltransferases.

Animals↗
PubMed1994

Hereditary progressive dystonia with marked diurnal fluctuation caused by mutations in the GTP cyclohydrolase I gene.

Hereditary progressive dystonia with marked diurnal fluctuation (HPD) (also known as dopa responsive dystonia) is a dystonia with onset in childhood that shows a marked response without any side effects to levodopa. Recently the gene for dopa responsive dystonia (DRD) was mapped to chromosome 14q. Here we report that GTP cyclohydrolase I is mapped to 14q22.1-q22.2. The identification of four independent mutations of the gene for GTP cyclohydrolase I in patients with HPD, as well as a marked decrease in the enzyme's activity in mononuclear blood cells, confirms that the GTP cyclohydrolase I gene is a causative gene for HPD/DRD. This is the first report of a causative gene for the inherited dystonias.

Age of Onset↗
PubMed1994

Gastroenterology.

Explore the source record for details and available documents.

Gastroenterology↗
PubMed1994

Identification and diameter assessment of gastric submucosal vessels using infrared electronic endoscopy.

In this study, an electronic endoscope was applied for observation of gastric submucosal vessels, with infrared illumination, in anesthetized dogs. An in-vivo spectrophotometry showed that infrared light at 620-820 nm penetrates the abdominal and gastric wall. During the endoscopy performed in dogs, the infrared radiation penetrated the abdominal wall and gastric wall from the outside, and was detected by the endoscope's charge-coupled device. A television monitor displayed a network of gastric vasculature, which was identified as veins in the gastric wall by injecting saline or indocyanine green into the vein. Using this system, it was possible to measure venous diameters of more than 0.2 mm by comparison with a reference wire. The diameter obtained by the image analysis correlated lineally to that of a vascular template prepared from the same stomach. Thus, it may become possible to assess gastric submucosal hemodynamics using infrared endoscopy, a new application in electronic endoscopy.

Abdominal Muscles↗
PubMed1994

Construction of an equalized cDNA library from human brain by semi-solid self-hybridization system.

A cDNA library enriched in clones for mRNA species (an equalized cDNA library) was constructed from human brain employing semi-solid self-hybridization system and cDNA amplification by in vitro transcription. Sequence analysis of the clones in the cDNA library indicated that (1) clones representing abundant species such as those of mitochondrial origin and expression sequence taq (EST) are drastically reduced in their proportion compared to the original library and (2) clones representing rare mRNA species or which do not have matched sequences in the database increased substantially in their proportion. cDNA libraries thus constructed, therefore, are a good source for cloning of cDNA for rare mRNA species from specific mammalian tissues and also for direct expression cloning since the inserts maintained their original molecular sizes after equalization.

Base Sequence↗
PubMed1994

Activation of the alternative pathway of human complement by apoptotic human umbilical vein endothelial cells.

Complement activation generally does not occur on homologous cells. We observed C3 deposition on cultured human umbilical vein endothelial cells (HUVEC) when those which had died of apoptosis were treated with human serum. The C3 deposition on apoptotic HUVEC required Mg2+ but not Ca2+. In addition, the incubation of apoptotic HUVEC with purified C3, B, and D in the presence of Mg2+ resulted in C3 deposition. These results indicated that the C3 deposition on apoptotic HUVEC is mediated by the activation of the alternative complement pathway. C3 contains an intrachain thioester bond in the alpha chain (110 kDa) and upon activation to C3b, binds with membrane molecules by forming an ester or amide bond. Western blotting of reduced C3b-membrane molecule complexes, isolated from serum-treated apoptotic HUVEC by immunoprecipitation with anti-C3, revealed the covalent binding of C3b to several membrane molecules. Most of the C3b-membrane molecule complexes were cleaved by hydroxylamine, suggesting covalent binding via an ester bond. The molecular mass of the major alpha chain fragment released by hydroxylamine treatment was not 105 kDa but 68 kDa, which corresponds to the alpha 1 fragment of iC3b. These results indicate that most of the C3b on HUVEC was cleaved at its alpha' chain to yield iC3b, which consists of three disulfide-linked polypeptide chains and is a ligand of the complement receptor type 3 (CR3) of phagocytes. These results suggest that apoptotic HUVEC can activate the alternative pathway of the homologous complement and that the complement is related to the clearance of apoptotic cells by phagocytes.

Apoptosis↗
PubMed1994

Familial juvenile parkinsonism: clinical and pathologic study in a family.

We describe a family with juvenile-onset parkinsonism, which improved following sleep. Four of the five siblings in this family developed a similar onset of parkinsonism at an early age, and the parents were first cousins. In one of the siblings, a 67-year-old woman, pathologic changes at autopsy were confined to the substantia nigra pars compacta (SNPC) and locus ceruleus. The SNPC revealed obvious neuronal loss and gliosis in the medial and ventrolateral regions. In the remainder of the SNPC and the locus ceruleus, the population of neurons was reduced and there was low melanin content in most of the neurons but no detectable gliosis or extraneuronal free melanin pigment suggestive of a neurodegenerative process. There were no Lewy bodies. The entire pathologic picture was different from that of Lewy body Parkinson's disease.

Adult↗
PubMed1994

Mitochondrial encephalomyopathy: elevated visual cortex lactate unresponsive to photic stimulation--a localized 1H-MRS study.

We used localized H-magnetic resonance spectroscopy (MRS) to study the metabolic changes in the visual cortex of patients with mitochondrial encephalomyopathy. Measurement of metabolite levels in the occipital visual cortex obtained in the dark with seven normal subjects and with four patients (all four of whom had Kearns-Sayre syndrome [KSS]) showed high lactate levels in the patients. Photic stimulation (PS) in four normal volunteers showed that lactate increased immediately after the start of PS and that it decreased to the baseline level with continued PS. Lactate in the resting state was higher in the KSS patients than in the controls, and, unlike the controls, the KSS patients showed no significant elevation of lactate with PS.

Humans↗
PubMed1994

A clinical and pathologic study of a large Japanese family with Machado-Joseph disease tightly linked to the DNA markers on chromosome 14q.

The gene locus for Machado-Joseph disease (MJD) has been mapped to chromosome 14q by linkage analysis, mainly using a single large Japanese family. We studied the clinical and neuropathologic findings of this family with MJD, comparing them with those of spinocerebellar ataxia 1 (SCA1) and spinocerebellar ataxia 2 (SCA2) families. The pedigree included 30 affected persons in 125 members of five generations. Neurologic examination of 21 patients revealed that dystonia, difficulty in eyelid opening, slowness of movements, bulging eyes, and facial-lingual fasciculation-like movements or myokymia are characteristic of this MJD family, although these three autosomal dominant spinocerebellar degenerations have several neurologic signs and symptoms in common. In contrast with SCA1 and SCA2, degeneration of the subthalamopallidal system and relative sparing of the olivocerebellar system were the main neuropathologic features of MJD.

Adult↗
PubMed1994

Identification of sublines of inbred strains of mice and assessment of genetic relationships between substrains or sublines by DNA fingerprinting.

Identification of substrains or sublines of inbred mice and assessment of genetic relationships among them were performed on the basis of DNA fingerprinting using M13 phage DNA as a probe. We used eight C57BL/6 sublines (J parallel Jcl, J parallel Jms, J parallel Slc, J parallel Nrs, J parallel Yok, Jah, N parallel Crj, N parallel Jcl) and eleven C3H/He sublines, (J, J parallel Jcl, J parallel Yok, J parallel Nrs, J parallel Jms, N, N parallel Jcl, N parallel Crj, Slc, Jah, Nrs). Two kinds of restriction endonucleases (HinfI and PstI) were used. It was found that: 1) DNA fingerprint within each subline showed identical patterns. 2) Most sublines of C57BL/6 and C3H/He could be identified using DNA fingerprinting with HinfI except between N parallel Crj and Slc, and among J, J parallel Nrs and J parallel Yok in C3H/He. DNA fingerprints with PstI endonucleases showed low polymorphic banding patterns. 3) A dendrogram constructed from DNA fingerprint patterns reflected generally the genealogy of the sublines used. 4) DNA fingerprinting, therefore, seemed to be suitable for the genetic monitoring and assessment of genetic relationships among sublines of inbred mice having close relationships.

Animals↗