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Biomedical subjects

S Sumi

Publications and source records attributed to S Sumi.

At least 145 records · Page 8Linked to original sources
PubMed1989

[A study of intercellular communication of human transitional cell carcinoma cell lines].

Intercellular communication (IC) was investigated by a dye transfer method in 5 human bladder carcinoma cell lines, JTC-29, JTC-30, JTC-32, HUB-41 and T-24 which showed various histological anaplasia when transplanted into nude mice. IC was investigated as follows; 1) IC among cells of each bladder carcinoma cell lines, 2) IC between various combination of different cell lines and 3) IC between cells of bladder carcinoma cell lines and fibroblasts prepared from the human skin or prostate. High IC was observed among JTC-30 cells which showed a differentiated pattern when transplanted into nude mice. JTC-32 and HUB-41, of which transplanted tumors showed poorly differentiated patterns, demonstrated lower IC than JTC-30. Statistical significance was present only between JTC-30 and JTC-32 cells (p less than 0.05). T-24 which formed histologically anaplastic tumor in nude mice demonstrated markedly poor IC. Second, IC between two different cell lines was demonstrated only between JTC-30 and JTC-32. Third, fibroblast from the skin and prostate had high IC but showed apparent IC with none of bladder carcinoma cell lines. These findings indicate that ICs of bladder tumor cells vary with cell lines tested and appear to decrease with progress of malignant anaplasia. Furthermore, the fact that there is sometimes high IC and sometimes lack of IC between differentiated and undifferentiated tumor cells suggests a possible role of IC in prevention of malignant progression. The present study provides no evidence of IC between bladder tumor cells and fibroblasts, which in some reports have been suggested to be an important phenomenon in evaluating the metastatic capacity of cancer cells.

Animals↗
PubMed1988

Role of sulphated tyrosine residue in influencing the biologic activity of human cholecystokinin-33.

To evaluate the role of the sulphated tyrosine residue in position 27 in human cholecystokinin-33, parallel bioassay of the sulphated form of human cholecystokinin-33 and the unsulphated form of human cholecystokinin-33 was performed on the pancreatic protein secretion. Both peptides increased the protein output in a dose-related manner. However, the sulphated form possessed a considerably higher activity than the sulphated form. The relative potency of the unsulphated human cholecystokinin-33 compared to that of the sulphated human cholecystokinin-33 (taken as 1.0) was 0.08. From the results, it was suggested that the sulphated tyrosine may play an important role in controlling the activity of the longer molecular forms as well as that of the smaller forms of cholecystokinin.

Animals↗
PubMed1988

Effect of synthetic human cholecystokinin-33 on exocrine pancreas.

Synthetic human cholecystokinin-33 was first evaluated with respect to the biological activity on the pancreatic protein secretion. Human cholecystokinin-33 increased pancreatic protein secretion in a dose-related manner. The relative molar potency of this substance compared to that of synthetic cholecystokinin-8 (taken as 1.0) was 0.92. This study supports the concept that longer molecular forms of cholecystokinin are quantitatively important mediators of biological action of cholecystokinin on the pancreas.

Animals↗
PubMed1988

Effects of intravenous ethanol on hepatic and pancreatic blood flow in dogs.

Changes in hepatic and pancreatic blood flow in response to ethanol infusion were determined simultaneously and continuously in anesthetized dogs, using a transit-time ultrasonic flowmeter and a laser-Doppler flowmeter. In addition, the effect of intravenous ethanol on exocrine pancreatic secretion was investigated. With a background infusion of secretin, ethanol (1.3 g/kg body wt) was infused intravenously over a 40-min period. Ethanol infusion significantly increased blood flow in the common hepatic artery (by 49%, at the time of the cessation of ethanol infusion), and this increased flow was maintained for 60 min after the cessation of ethanol infusion. In contrast, blood flow in the portal vein was not altered significantly by ethanol. Pancreatic blood flow and secretion showed no significant difference from those seen in the controls. Our data suggest that intravenous ethanol induces a redistribution of the splanchnic blood flow. The increased hepatic arterial flow seen in response to ethanol may play an important role in preventing ethanol-induced hypoxic liver damage.

Animals↗
PubMed1988

Effects of synthetic human gastric inhibitory polypeptide on splanchnic circulation in dogs.

Changes in blood flow in the celiac artery, superior mesenteric artery, and pancreas in response to an intravenous injection of synthetic human gastric inhibitory polypeptide (GIP) were determined simultaneously and continuously in anesthetized dogs, using a transit-time ultrasonic flowmeter and a laser-Doppler flowmeter. Injection of GIP significantly increased superior mesenteric arterial flow in a dose-related manner (by 9%, 43%, and 139% at 30 s after an injection at the doses of 3, 50, and 800 pmol/kg, respectively). In contrast, celiac arterial flow was not significantly altered by GIP at any of the three doses. Calculated vascular resistance in the superior mesenteric artery decreased after GIP infusion, whereas that in the celiac artery was not changed by GIP. Pancreatic blood flow decreased significantly after GIP injection at the doses of 50 and 800 pmol/kg (by 11% and 17%, respectively). Our data indicate that there is a substantial difference in the hemodynamic responses to GIP among splanchnic organs, and suggest that GIP acts specifically on the mesenteric vasculature.

Animals↗
PubMed1988

Simultaneous measurement of hepatic arterial and portal venous flows by transit time ultrasonic volume flowmetry.

Simultaneous measurement of the hepatic artery and the portal vein was performed successfully upon 15 anesthetized patients during abdominal operations with the use of transit time ultrasonic volume flowmeter. The hepatic arterial flow, portal venous flow and total hepatic flow were 267.3 +/- 21.2, 746.4 +/- 41.3 and 1,010.7 +/- 52.7 milliliters per minute, respectively. The ratio of hepatic arterial flow to portal venous flow was 0.36 +/- 0.03. Temporary occlusion of the portal vein resulted in a significant increase in hepatic arterial flow (23.6 +/- 4.3 per cent, p less than 0.01), whereas temporary occlusion of the hepatic artery did not alter portal venous flow significantly. Occlusion of the common hepatic artery induced a significant decrease in hepatic arterial flow (p less than 0.05), but did not alter portal venous flow significantly. The results of this approach had useful clinical meanings in one patient in whom the Appleby's operation was performed in which sufficient hepatic arterial flow was needed after the common hepatic artery was ligated. Data are presented for hepatic circulation measured by transit time ultrasonic volume flowmeter, which is a good device to use to assess portal venous flow as well as hepatic arterial flow with reproducibility and stability.

Adult↗
PubMed1988

[Study on splanchnic circulation: measurement of the liver blood flow].

In anesthetized patients during abdominal surgery, hepatic artery and portal vein flows were measured simultaneously utilizing an ultrasonic transit-time volume flowmeter. The total hepatic blood flow was 994.6 +/- 52.4 ml/min. The hepatic artery flow and the portal vein flow were 260.0 +/- 23.8 ml/min and 730.8 +/- 41.3 ml/min, respectively. The ratio of hepatic artery flow to portal vein flow was 0.37 +/- 0.04. A significant increase in hepatic artery flow (p less than 0.01) followed portal vein occlusion, whereas no significant change was observed in portal vein flow after hepatic artery occlusion. Common hepatic artery occlusion resulted in a significant decrease in hepatic artery flow (p less than 0.05), but no significant change was observed in portal vein flow. The present study firstly demonstrated that ultrasonic transit-time volume flowmeter is a device to quantitatively assess hepatic artery and portal vein flows with good reproducibility and stability in human subjects. This easy and simple technique seemed to have wide clinical application to abdominal surgery and would have a promising in studying splanchnic blood flows in various situations such as in cases of hepatectomy and portal hypertension.

Adult↗
PubMed1988

[Adrenal myelolipoma: two case reports].

We report 2 cases of adrenal myelolipoma which were suspected preoperatively and confirmed by surgical resection. As with most cases previously reported, the lesions were found in obese, middle-aged persons. Laboratory tests of adrenal function revealed values within the normal level. Excretory urography showed radiolucent masses in the suprarenal area displacing the kidney inferiorly. Computerized tomography revealed well-defined masses consisting of fat density areas and higher density areas. Ultrasonography demonstrated hyperechoic, heterogeneous tumors. The tumors were shown to be hypovascular and adrenal in origin on the angiogram. An operation was performed because of complaint of flank pain in the first case and hypertension associated with elevated plasma renin activity in the second case. The pathological study disclosed typical adrenal myelolipoma with a mixture of hematopoietic and adipose tissue. Adrenal myelolipoma is clinically unusual and only 41 cases with premortem diagnosis have been reported in English literature. We herein report the 14th and 15th cases in Japan. As computerized tomography and ultrasonography become more widely used, we believe that the number of cases difficult to differentiate from a malignancy will increase.

Adrenal Gland Neoplasms↗
PubMed1987

Effect of synthetic neuromedin U-8 and U-25, novel peptides identified in porcine spinal cord, on splanchnic circulation in dogs.

Two novel peptides which exert a potent stimulant effect on rat uterus smooth muscle have recently been identified in porcine spinal cord. These peptides designated neuromedin U-8 and U-25 have been reported to exert a hypertensive effect in rats. But further biological activities are not known. In the present study, the effect of these peptides on blood flow in portal vein, superior mesenteric artery and pancreatic tissue and on blood pressure were examined in dogs, utilizing recently developed ultrasonic transit time volume flow meter and laser Doppler flow meter. Neuromedin Us potently reduced blood flow in superior mesenteric artery. The minimum reductions could be observed even at very small doses of neuromedin U-25 (32 fmol/kg) and U-8 (90 fmol/kg), while the maximal reductions of 48.4 and 51.0% were attained at the doses of 320 pmol/kg (U-25) and 900 pmol/kg (U-8), respectively. These peptides also reduced portal vein blood flow, and the maximal reductions of 42.1 and 37.2% were attained at the doses of 32 pmol/kg (U-25) and 90 pmol/kg (U-8), respectively. On the other hand, blood flow in pancreatic tissue increased slightly with the maximal increases of 13.8% at 3.2 pmol/kg (U-25) and 11.8% at 9 pmol/kg (U-8), respectively. The maximal increases of blood pressure were 5.2% at 320 pmol/kg (U-25) and 4.3% at 90 pmol/kg (U-8). Furthermore, neither neuromedin U-25 nor U-8 influenced the axillary artery blood flow, suggesting their selective effect on splanchnic blood flow. Because of the potent and probably selective activity on splanchnic circulation, neuromedin U-25 and U-8 may well be recognized as physiologically significant novel neuropeptides or hormones.

Animals↗
PubMed1987

Effect of synthetic neuromedin-N, a novel neurotensin-like peptide, on exocrine pancreatic secretion and splanchnic blood flow in dogs.

Neuromedin-N, a novel neurotensin-like peptide, has recently been identified from porcine spinal cord by using a bioassay for a stimulatory effect on guinea pig ileum. The amino acid sequence of the peptide has been determined to be Lys-Ile-Pro-Tyr-Ile-Leu, which is quite homologous to the COOH-terminal sequence of neurotensin. In this study, the effect of neuromedin-N on pancreas and splanchnic blood flow was investigated in eight dogs. Intravenous injections of graded doses of synthetic neuromedin-N caused a dose-dependent decrease of systemic arterial pressure and a dose-dependent increase in both portal and superior mesenteric arterial blood flow, which were measured with transit time ultrasonic flow meter. Volume and protein output of the pancreatic juice were also increased significantly by Neuromedin-N. Pancreatic capillary blood flow measured with laser Doppler flowmetry was increased in a dose-related manner. The present study first demonstrated that neuromedin-N retains a potent stimulatory effect on the pancreas and splanchnic circulation, indicating that this peptide is one of the biological active forms of neurotensin-like peptide in mammals. This study also leads to the suggestion that this peptide possesses physiological significance as a novel neuropeptide.

Animals↗
PubMed1987

[A case of gastric cancer in which long-term administration of 5'-deoxy-5-fluorouridine (5'-DFUR) proved effective].

A patient with gastric cancer (mucinous adenocarcinoma), classified as Borrmann Type 4, refused surgery and a chemotherapy regimen was applied. 5'-DFUR (5'-deoxy-5-fluorouridine) was administered orally at 1,200 mg/day for 23 weeks, for a total dosage of 110.8 g. The patient showed marked remission: the tumor nearly disappeared, distensibility reappeared from the central region of the corpus ventriculi to the incisura angularis, and only small protrusions classified by Yamada's criteria as Type I, remained on the anterior and posterior wall and pars pylorica of the lesser curvature. Side effects were slight anorexia and diarrhea. These could be avoidable by temporal interruption of administration or dosage reduction, to allow long-term treatment. This case can be considered to be one example in which 5'-DFUR proved effective against gastric cancer.

Adenocarcinoma, Mucinous↗