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S Matsutani

Publications and source records attributed to S Matsutani.

At least 37 records · Page 2Linked to original sources

[Recent progress in the diagnosis of gastroesophageal varices].

Recent advances in the diagnosis of gastroesophageal varices are reviewed in this paper. Endoscopy, angiography, ultrasound, and ultrasound Doppler are now employed in the diagnosis of varices. As for endoscopic diagnosis, new criteria for the evaluation of gastroesophageal varices have been applied. Angiography is now not only used to demonstrate the varices and collateral circulations in portal hypertension but also used in the embolization therapy for large gastric varices or intractable esophageal varices. Ultrasound and color Doppler are now widely used in the diagnosis of portal hypertension because of its noninvasiveness and conveniency. Furthermore, in its use in endoscopy, varical vessels and blood flow in the wall of the esophagus and the stomach can be directly demonstrated. Recent advances in these diagnostic modalities will made it possible to diagnose gastroesophageal varices and evaluate the pathophysiology in patients with portal hypertension more precisely.

Angiography↗

Effect of thielocin A1 beta on bee venom phospholipase A2-induced edema in mouse paw.

Several investigators have reported that inactivation of secretory phospholipase A2 purified from bee venom with p-bromophenacyl bromide, an irreversible inhibitor, before injection resulted in attenuation of the subsequent inflammatory reaction in the mouse paw edema model. Recently, thielocin A1 beta, a novel secretory phospholipase A2 inhibitor from fungi, was found to suppress histamine release from mast cells stimulated with secretory phospholipase A2. These observations led us to examine the effect of thielocin A1 beta against secretory phospholipase A2-induced paw edema. Thielocin A1 beta inhibited bee venom phospholipase A2 in a dose-dependent manner (IC50 = 1.4 microM). In addition, the inhibition of bee venom phospholipase A2 was noncompetitive (Ki = 0.57 microM) and reversible. Subplantar injection of bee venom phospholipase A2 produced a rapid but transient edematous response. Coinjection of thielocin A1 beta (1 microgram/paw) with bee venom phospholipase A2 resulted in a 44.7 +/- 4.6% reduction of edema formation. This anti-edema action was not enhanced by cyproheptadine (antihistamine/antiserotonin). These results suggest that thielocin A1 beta shows edema-reducing activity via inhibition of the phospholipase A2 activity which participates in histamine release by mast cells.

Acetophenones↗

Response of blood flow to vasopressin in the collateral left gastric vein in patients with portal hypertension.

BACKGROUND/AIMS: A problem in pharmacotherapy for bleeding varices in portal hypertension is non-responders. The aim of this study was to elucidate the features of hemodynamic response to vasopressin in the gastroesophageal collateral vein in patients with esophageal varices. METHODS: Flow velocity in the portal and the collateral left gastric vein was measured with an echo-Doppler flowmeter before and during infusion of vasopressin, 0.2 U/min, in 41 patients with cirrhosis and esophageal varices. RESULTS: The decrease in flow velocity in the left gastric vein with vasopressin (-29 +/- 25%) was significantly smaller than that in the portal vein (-56 +/- 20%). There was no or only minimal change in flow velocity in the left gastric vein in 39% of the patients, especially in those with large-size varices. In 28 patients examined by portal catheterization, changes in flow velocity in the left gastric vein were correlated with portal pressure, and portal pressure in non-responders was significantly higher than that in responders (non-responders: 363 +/- 49, responders: 312 +/- 41 mmH2O, p < 0.05). CONCLUSIONS: It was concluded that hepatofugal blood flow in the gastroesophageal collateral is not readily reduced by vasopressin. However, as the study was performed in a stable condition without variceal bleeding, whether these hemodynamic features will apply during acute variceal bleeding in patients who are known to have a poor hemodynamic response to vasopressin remains to be elucidated.

Aged↗

Isolation and biological activity of thielocins: novel phospholipase A2 inhibitors produced by Thielavia terricola RF-143.

Thielocins A2 alpha, A2 beta, A3, B1, B2 and B3 were isolated as a novel family of phospholipase A2 inhibitors from the fermentation broth of Thielavia terricola RF-143 together with thielavins and thielocins A1 alpha and A1 beta. The most potent inhibitory activity (IC50 = 0.0033 microM) against rat group II phospholipase A2 was shown by thielocin A1 beta. Against human group II phospholipase A2, thielocin B3 (IC50 = 0.076 microM) was the most potent.

Animals↗

[Study of the changes in portal hemodynamics after endoscopic injection sclerotherapy with reference to the variceal recurrence].

Endoscopic injection sclerotherapy (EIS) combined with percutaneous transhepatic obliteration was performed in 63 cirrhotic patients with esophageal varices. In all patients, esophageal varices were completely disappeared after EIS. To investigate risk factors for recurrence of esophageal varices after EIS, hemodynamic changes in the portal system before and after EIS were studied by portal vein catheterization and ultrasonography. In patients in whom portal pressure rose after EIS, recurrence of varices was observed in high incidence (p < 0.05). Furthermore, variceal recurrence appeared frequently in patients with progressive splenomegaly after EIS (p < 0.05). During post-EIS course, new appearance or increase in size of non-variceal portosystemic collaterals was detected by ultrasonography in 22% of the patients. In these patients, variceal recurrence rate was low (p = 0.09). In patients with shunts around the splenic hilum, variceal recurrence rate was lower compared with the patients with paraumbilical vein (p < 0.05). Prognostic factors for variceal recurrence were analysed using multiple regression model. It was suggested that the absence of non-variceal portosystemic collaterals was the most risky factor. In conclusion, observation of portal hemodynamics is considered to be useful for the long-term management of patients with esophageal varices treated with EIS.

Adult↗

Genetic evidence for IS1 transposition regulated by InsA and the delta InsA-B'-InsB species, which is generated by translation from two alternative internal initiation sites and frameshifting.

Insertion sequence IS1 contains two reading frames, insA and B'-insB, which are responsible for its transposition, and was previously shown to express two proteins. The first, InsA, is the product of insA. The second, InsA-B'-InsB is a fusion of InsA with the product of B'-insB. Synthesis of this protein occurs by a -1 frameshift from the 3' region of the insA frame to the open reading frame B', extending from the 5' end of the insB frame. Here, I have shown genetically that IS1 encodes the third species delta InsA-B'-InsB: delta InsA-B'-InsB uses two alternative initiation codons in the middle of the insA frame, and is produced by a frameshift mechanism similar to that used in InsA-B'-InsB expression. Deletion of the small region preceding these initiation codons resulted in decreased expression of delta InsA-B'-InsB, suggesting that the small region play some role in the translation initiation. Surprisingly, it was found that delta InsA-B'-InsB has a transposase-like function and InsA can stimulate the transposition promoted by delta InsA-B'-InsB, while delta InsA-B'-InsB seemed to bind to the left terminal inverted repeat (IRL) of IS1 and inhibit transposition when it was present in excess, as well as InsA represses transposition. It is likely that IS1 transposition activity depends on the ratio of InsA to delta InsA-B'-InsB. A double missense mutation of the internal initiation codons resulted in decreased cointegration activity, showing that delta InsA-B'-InsB is responsible for transposition but InsA-B'-InsB is probably not. Some IS elements, which also contain two tandem, out-of-phase, overlapping genes, appear to express deleted fusion proteins like delta InsA-B'-InsB, but the functions are unknown. The complex phenomena of transposition and its control found in IS1 may be more general in the other mobile DNAs.

Amino Acid Sequence↗

Thielocin B3, a novel antiinflammatory human group II phospholipase A2 specific inhibitor from ascomycetes.

Evidence accumulated to date suggests that extracellular group II phospholipase A2 (PLA2-II) is involved in the pathogenesis of inflammatory disease. During screening for PLA2 inhibitors, we found a novel PLA2 inhibitor named thielocin B3 in the culture broth of an ascomycetes. Thielocin B3 strongly inhibited human PLA2-II (IC50 = 0.076 microM) in a reversible and noncompetitive manner (Ki = 0.098 microM), whereas it inhibited human group I PLA2 only weakly (IC50 = 18 microM). It also quenched the tryptophan fluorescence of Naja mocambique venom PLA2; almost 100% quenching being attained at a thielocin B3/enzyme molar ratio of 1.0. Its inhibitory activity toward human PLA2-II and Naja mocambique PLA2 was markedly decreased by methylation of its two carboxyl groups, while the quenching observed for Naja mocambique PLA2 was not altered. These results suggest that the two carboxyl groups do not participate in the binding of thielocin B3 to the enzyme, but play a crucial role in the PLA2 inhibition. Furthermore, in the rat carrageenan-induced pleurisy model, thielocin B3 significantly reduced both exudate volume and PLA2 activity in the exudate when coinjected with carrageenan.

Animals↗

[Diffuse gastric mucosal redness in liver cirrhosis--with special reference to portal hemodynamics].

The clinicopathological characteristics of the diffuse gastric mucosal redness were studied in 235 patients with liver cirrhosis. Moreover, in 96 patients in whom percutaneous transhepatic portal catheterization was carried out, the relationship was studied between gastric mucosal lesions and portal hemodynamic aspect with reference to portal vein pressure and extrahepatic collaterals. Extrahepatic collaterals were divided into three groups, which related either of cephalad, caudal and peri-abdominal as the most prevalent extrahepatic collateral on portographic findings. The frequency of the diffuse gastric mucosal redness was increased with the elevation of portal vein pressure, and it was seen more frequently in patients with cephalad collaterals than in caudal. However, the diffuse gastric mucosal redness was seen less frequently in patients with cephalad collateral accompanied with the development of renal shunts. Multiple logistic model analysis showed significant correlation between the diffuse gastric mucosal redness and the development of cephalad collaterals. These results suggest that the gastric mucosal circulation in liver cirrhosis is strongly affected by the development of portosystemic collaterals in portal hypertension.

Aged↗

[Ultrasonography in the diagnosis of liver cirrhosis].

Ultrasound is now widely used in the diagnosis of liver diseases. Applications of ultrasound in the diagnosis of liver cirrhosis are reviewed in this paper. Characteristic findings of liver cirrhosis in ultrasound are nodular liver surface, round edge, and hypoechoic nodules in liver parenchyma which represent regenerative nodules of cirrhotic liver. Detection of hypoechoic nodule more than 10 mm is important in the early diagnosis of hepatocellular carcinoma. Detection of splenomegaly, ascites, and portosystemic collaterals is possible by ultrasound. Evaluation of portosystemic collaterals is beneficial in the management of esophagogastric varices and portosystemic encephalopathy. Ultrasound is useful in the non-invasive diagnosis and long-term management of cirrhotic patients.

Ascites↗

Elaboration of glial cell processes in the rat olfactory bulb associated with early learning.

Odor preference training early in life induces anatomical changes in focal areas of the glomerular layer of the rat main olfactory bulb. We examined the associated focal changes in glial cell morphology using immunohistochemistry for glial fibrillary acidic protein (GFAP) and found that the density of immunoreactive processes was higher in glomeruli responsive to an odor for which pups had developed a preference. The increase in process density in trained pups was specific to focal responsive regions of the bulb, revealed with [14C]2-deoxyglucose autoradiography. There was no change in the number of GFAP-immunoreactive cells between trained and control pups.

Aging↗

Distribution of the Shigella sonnei insertion elements in Enterobacteriaceae.

The distribution of IS1, IS600, IS629, IS630 and IS640, present in an Shigella sonnei strain, was examined in strains belonging to various species of enteric bacteria. Four Shigella species including Sh. sonnei contained all IS elements, several of which were in large numbers, and showed species-specific distribution patterns. The other strains contained some of the IS elements in a few copies or none at all, except for some clinical isolates in the Escherichia coli strains, which showed similar distribution patterns to those of the Shigella species, suggesting that the E. coli isolates are closely related to those in Shigella. The IS elements examined may be used to classify various bacterial strains and to identify the Shigella strains and some of the E. coli strains to be isolated from various sources.

DNA Transposable Elements↗

Doppler color flow imaging in the detection and quantitative measurement of the gastroduodenal artery blood flow.

The purpose of this article was to investigate the detection rate of gastroduodenal artery blood flow (GDABF), and to measure its velocity and volume flow rate using Doppler color imaging. The GDABF was detected in 40 of 41 (98%) normal subjects with longitudinal scanning and in 36 (88%) with transverse scanning. The velocity of the GDABF was 21 +/- 8 cm/sec (m +/- SD) and the volume flow rate was 67 +/- 20 mL/min. Without color Doppler, the vascular lumina of the GDA was demonstrated in 27 (66%) subjects by longitudinal scanning and in 26 (63%) by transverse scanning. The hemodynamics of the GDA were revealed noninvasively using Doppler ultrasonography in a patient with a malignant islet cell tumor of the pancreas and one with a ductal cell carcinoma of the pancreas.

Adenocarcinoma↗

Hemodynamics of the left gastric vein in portal hypertension.

BACKGROUND: Esophageal varices reflect the hemodynamics of the left gastric vein, which can now be studied by Doppler ultrasonography. The purpose of this study was to elucidate the hemodynamic features of the left gastric vein in portal hypertension. METHODS: Flow direction and velocity in the left gastric vein were examined by the pulsed Doppler flowmeter in 53 healthy adults and 216 patients with liver cirrhosis. RESULTS: Flow direction was hepatopetal in all healthy controls, whereas it was hepatofugal in 72% of the patients with esophageal varices. In the early stage of mild esophageal varices, flow direction was still hepatopetal. However, in portal pressure > 250 mm H2O, hepatofugal flow was highly frequent (56 of 59 patients, 95%). Hepatofugal flow velocity in patients with varices was 8.5 +/- 2.5 cm/s in mild varices, 11.6 +/- 2.4 cm/s in intermediate varices, and 13.8 +/- 3.4 cm/s in marked varices. Variceal bleeding was frequent in patients with a flow velocity > 15 cm/s (7 of 14 patients, 50%). Flow velocity in the left gastric vein increased after ingestion of glucose in 43 of 56 patients with esophageal varices. CONCLUSIONS: In portal hypertension, as the size of varices enlarged, hepatofugal blood flow in the left gastric vein increased in parallel. High flow velocity in the left gastric vein was strongly associated with variceal bleeding. Increase of blood flow after ingestion of glucose suggests postprandial increase in variceal flow.

Administration, Oral↗

Isolation of a subclonal cell line of PC12 transfected with dexamethasone-regulated ras oncogene: morphological differentiation, biochemical properties, and tumorigenicity.

We have isolated and characterized a new subclonal cell line designated as MR31, which was obtained by transfection of PC12 cells with a glucocorticoid-regulated ras oncogene. The mRNA derived from the c-Ha-ras gene was proved to be expressed on exposure of the MR31 cells to dexamethasone, the highest value being attained at 8 h. MR31 cells rapidly extended neurite-like processes within 24 h in response to dexamethasone as well as nerve growth factor (NGF). The time of onset of neurite outgrowth induced by dexamethasone corresponded to the time when the highest ras mRNA level was observed. The catecholamine content of MR31 cells was found to be twice that of PC12 cells. A time course study on the effects of dexamethasone or NGF on cells showed that the former caused an increase in dopamine, a major catecholamine, to twofold the control level at 48 h after the treatment, while the latter caused a decrease in the dopamine level. These effects on catecholamines were almost the same in MR31 and PC12 cells. The acetylcholinesterase activity of MR31 cells was enhanced by both dexamethasone and NGF, whereas that of PC12 cells was enhanced by NGF, but not by dexamethasone. The changes in acetylcholinesterase activity were correlated with neurite outgrowth. Electron-microscopically, MR31 cells were not different from PC12 cells. MR31 cells exhibited extremely decreased tumorigenicity as compared with PC12 cells. The morphological and biochemical properties of MR31 cells remained constant, even after repeated passages.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗