Biomedical subjects

K Suda

Publications and source records attributed to K Suda.

At least 217 records · Page 12Linked to original sources

PubMed1991

[A comparison between hyperplasia of ductal epithelium and mucin producing tumor of the pancreas].

A comparison between papillary proliferation of the ductal epithelium with goblet cell metaplasia (Hyperplasia) and mucin producing tumor (MPT) of the pancreas was studied clinicopathologically. Hyperplasia was found in 35 out of 56 autopsied cases (62.5%) and revealed an age-related frequency. Hyperplasia was situated chiefly in the branches of pancreatic duct, whereas MPT in both the main and branches of pancreatic duct. The ducts with hyperplasia frequently contained secretions in their lumens and were found in the proximity of isolated islets of Langerhans, while MPT consisted of high columnar and mucin producing cells, arranged in cyst-papillary pattern, filled with mucin and accompanied by disappearance of the surrounding parenchyma. Both Hyperplasia and MPT were frequently occurred in an elderly age group. Therefore, papillary hyperplasia of the ductal epithelium with goblet cell metaplasia and mucin producing tumor showed similar appearance, except for cellular atypism.

Adenocarcinoma, Mucinous↗

PubMed1991

[A comparison on between acute pancreatitis and chronic pancreatitis, special references to their fibrosis].

A comparison on fibrosis in between apparently uninvolved areas in acute pancreatitis (AP) and chronic pancreatitis (CP) was both histopathologically and immunohistochemically studied. Interlobular fibrosis in the apparently uninvolved areas (AP) was found in 7 out of 9 patients and accompanied by hemosiderin deposition in 6 patients, whereas that in only 2 out of 12 patients in CP. In the 2 remaining patients of AP without fibrosis, hemorrhage with inflammation was distributed in the interlobular spaces. Hence, AP was seldomly followed by CP. Interlobular fibrosis in CP immunostained positively to both anti-collagen Types I and III, whereas that in AP in four patients only. Fibrosis in the 3 remaining patients of AP whose illness was of less than one month's duration was positive against anti-collagen Type III only. Therefore, differences in both hemosiderin deposition and immunoreactivity against anti-collagen Type I in the interlobular fibrosis, except for longer surviving patients were observed in between acute and chronic pancreatitis.

Acute Disease↗

PubMed1991

Narrow duct segment distal to choledochal cyst.

"Narrow segments" (or stenotic portions) of the common bile duct (CBD) distal to cysts in two patients (a 50-yr-old woman and a 25-yr-old man) with choledochal cyst (CholCyst) were studied macroscopically and histologically. The narrow segments of the ducts were patent and connected with the main pancreatic duct extraduodenally, whereas the CBD in controls were neither dilated nor stenotic, and joined the main pancreatic duct within the duodenal wall. These narrow segments were 1 cm long. In case 1, a minute orifice was found in the narrow segment of the duct macroscopically and was identified microscopically as a small duct from a pancreatic lobule. In case 2, a small pancreatic duct also joined the narrow segment of the duct. These small pancreatic ducts were derived from the ventral pancreas, based on distribution of PP-islets. Therefore, the narrow duct distal to the cyst in patients with CholCyst (or congenital biliary dilatation) was considered to be a branch of the ventral pancreatic duct.

Adult↗

PubMed1991

[Histopathological study on fat necrosis with comparison between agonal stage and acute pancreatitis].

A histopathological study on fat necrosis with a comparison between patients in agonal stage and those with acute pancreatitis was presented. Fat necrosis was observed in 15 out of 56 autopsied cases (26.8%) which were selected randomly from the autopsy file. Fat necrosis was frequently stained blue or purple with Nile blue stain, suggestive of acid lipid. The necrosis was usually accompanied by fibrin thrombi in the capillaries and reparative foam cells, nor hemorrhage and hemosiderin deposition. In acute pancreatitis fat necrosis also reacted blue or purple with Nile blue stain in 8 out of 9 patients. Reparative reaction was composed of granulation tissue in 6 patients, frequently with organized thrombosis in the veins. Fat necrosis was accompanied by fibrin thrombi and either hemorrhage or hemosiderin deposition. Therefore, differences in both hemorrhage or hemosiderin deposition and reparative change were observed in fat necrosis between patients in agonal stage and those with acute pancreatitis.

Acute Disease↗

PubMed1991

[Relationship between an involvement of Oddi's sphincter in a choledochopancreatic junction and clinical appearances in 120 patients with anomalous arrangement of the pancreatico-biliary ductal system].

We studied relationship between an involvement of Oddi's sphincter in a choledochopancreatic junction and clinical appearances in 120 patients with anomalous arrangement of the pancreaticobiliary ductal system. The 120 composed of 83 with a sphincteric mechanism at the junction of the common bile and pancreatic duct and 37 without the sphincteric mechanism. We found that influences of sphincteric mechanism at the junction closely related to the length of the common duct between an orifice of the papilla of Vater and a junction of the common bile and pancreatic duct. And in all 83 with a sphincteric mechanism at the junction the length of the common duct showed less than 1.5 cm, and in all 37 without a sphincteric mechanism at the junction the common duct showed more than 1.5 cm in length. There was no correlation between a distribution of the sphincter muscle and clinical appearances, association with congenital choledochal cyst, cholelithiasis and bile duct cancer in the 120 patients.

Adult↗

PubMed1991

[Histopathological study on branches of the pancreatic duct in obstructive pancreatic disorders].

Branches of the pancreatic duct in obstructive pancreatic disorders were studied histopathologically. Obstructive pancreatic disorders were observed in 25 out of 32 patients with pancreatic carcinoma. The main pancreatic duct was dilated in all 25 cases. Luminal conditions in the branches of the pancreatic duct were divided as follows: dilated, obstructed and unchanged. The dilated duct was found in all 25 cases and showed mainly cystic dilatation with flat epithelia. The obstructed duct was found in 10 cases and revealed granulation tissue in the lumen, disappearance of epithelia and increase in the number of elastic fibers in the periductal space. The pancreatic tissue distal to the tumor frequently showed isolated islets of Langerhans with elastosis. Morphogenesis of elastosis was interpreted as follows: during the process of shortening or disappearance of the duct, elastic fibers increased in number and remained in the fibrous tissue. Hence, the elastosis was considered to be a remnant in which the pancreatic duct had once existed. Therefore, the branches of the pancreatic duct in obstructive pancreatic disorder were classified into four types as follows: dilated, obstructed, remnant and unchanged.

Adult↗

PubMed1990

The MAS-encoded processing protease of yeast mitochondria. Overproduction and characterization of its two nonidentical subunits.

The amino-terminal presequences of proteins imported from the cytoplasm across the mitochondrial inner membrane are cleaved off by a soluble matrix-localized protease composed of two nonidentical homologous subunits. In the yeast Saccharomyces cerevisiae, these are encoded by the nuclear MAS1 and MAS2 genes. We have now constructed yeast strains in which either one or both of the genomic MAS genes are controlled by a galactose-inducible strong promoter. In these strains, the intramitochondrial concentration of each MAS-encoded subunit as well as of the holo-protease can be varied over a wide range. When overproduced, the MAS1 protein precipitates in the matrix whereas the MAS2 protein remains soluble. The MAS2 protein was obtained at a purity of 98% in milligram amounts. The purified MAS2 subunit exists largely as a soluble 52-kDa monomer. Its cleavage activity is very low and might well reflect the 2% contamination by holoprotease. Activity is restored by adding the solubilized purified MAS1 subunit. Yeast cells depleted of one or both MAS subunits continue to import precursor proteins into mitochondria, but fail to cleave them; eventually the deficient cells stop growing. This growth arrest is partly suppressed on minimal medium or under conditions in which the cells are less dependent on mitochondrial metabolism. Depletion of the MAS1 subunit causes overproduction of the MAS2 subunit.

Cell Nucleus↗

PubMed1990

A yeast protein, homologous to the proteolipid of the chromaffin granule proton-ATPase, is important for cell growth.

We have characterized a gene, PPA1, adjacent to the yeast MAS2 gene. DNA sequence analysis of PPA1 predicts a hydrophobic protein of 23 kDa. This protein is homologous to the proteolipid of the bovine chromaffin granule proton ATPase and to the proteolipid of the yeast vacuolar proton ATPase. Gene disruption experiments indicate that the PPA1 protein is essential for viability in three unrelated yeast strains and important for optimal growth in a fourth strain.

Adenosine Triphosphatases↗

PubMed1990

Immunohistochemical and gross dissection studies of annular pancreas.

Three cases of annular pancreas were studied immunohistochemically on an embryological basis in relation to the duct system. Annular pancreatic tissue was characterized by abundant, irregularly shaped islets with a very high proportion of pancreatic polypeptide (PP) cells, similar to those in the postero-inferior part of the pancreatic head of controls. This PP-rich area fused with PP-poor areas in both the anterior and posterior portions, resulting in encirclement of the duodenum except for a few PP-poor areas. The pancreatic duct of the annular tissue passed from the anterior portion to the lateral and posterior portions, finally joining with the main pancreatic duct. No connection was present between the duct of the anterior portion and the main pancreatic duct. Therefore, the annular pancreatic tissue was revealed to arise from the ventral primordium, supporting Lecco's theory that the free end of the ventral anlage is fixed.

Child↗

PubMed1990

Portal venous tumor thrombosis associated with gastric adenocarcinoma.

Tumor thrombosis of the portal vein was identified retrospectively with computed tomography (CT) in four patients aged 66-77 years with gastric adenocarcinoma. Surgical, clinical, histopathologic, laboratory, and imaging findings were analyzed. Three patients showed an elevated alpha-fetoprotein (AFP) level (230-1,560 ng/mL [230-1,560 micrograms/L]). Immunohistochemical study revealed that AFP was produced by gastric carcinoma in two patients. Multiple metastatic foci in the liver appeared on CT and ultrasound (US) scans in all four patients. Echogenic thrombus was identified in three. There were no CT or US features that enabled differentiation of neoplastic from nonneoplastic thromboses. Angiography showed tumor vessels in only one patient: The thrombus was hypervascular in the arteriocapillary phase of celiac angiography but could not be differentiated from a much more common tumor thrombus seen in hepatocellular carcinoma. Nevertheless, gastric carcinoma should be considered a possibility in the diagnosis of portal venous tumor thrombosis, even if the serum AFP level is elevated and a liver tumor is identified.

Adenocarcinoma↗

PubMed1990

Islet amyloid polypeptide-like immunoreactivity (amylin) in rats treated with dexamethasone and streptozotocin.

Islet amyloid polypeptide (IAPP) is a 37 amino acid peptide present in pancreatic beta-cells. Pancreatic and circulating IAPP concentrations in rat models of diabetes were measured using a specific radioimmunoassay. Pancreatic IAPP-like immunoreactivity (IAPP-IR) in dexamethasone-treated rats was twice that of the control rats (1571 +/- 137 vs 657 +/- 176 (S.E.M.; n = 6) pmol/g), and this was reflected by similar changes in the plasma IAPP-IR (272 +/- 17 vs 102 +/- 10 pmol/l). In streptozotocin-treated rats, pancreatic IAPP-IR (200 +/- 90 pmol/g) was reduced compared with controls. There was a significant positive correlation between pancreatic and plasma IAPP-IR and insulin, with r values of 0.82 and 0.91 for the plasma and pancreas respectively. Characterization of pancreatic immunoreactivity, using gel chromatography, revealed two peaks of IAPP-IR, one which coeluted with synthetic human amidated IAPP and another peak, presumably a fragment or breakdown product, which eluted later. Chromatography of the plasma IAPP-IR revealed that greater than 90% of the IAPP-IR eluted in the void volume, although the remaining IR coeluted with the synthetic IAPP standard. These results are not straightforwardly compatible with the suggested role for IAPP as a hormonal, paracrine or autocrine inhibitory regulator of insulin secretion in the maintenance of carbohydrate homeostasis.

Amyloid↗

PubMed1990

Diacylglycerol accumulation is involved in the potentiating effect of A23187 on carbachol-stimulated amylase secretion from parotid gland.

We studied the role of sn-1, 2-diacylglycerol (DAG) accumulation in the potentiating effect of A23187 on carbachol (CCh)-stimulated amylase secretion from rat parotid acinar cells. A23187 (0.1 microM) linearly increased DAG accumulation with time for at least 30 min. At concentrations higher or lower than 0.1 microM, DAG levels increased for up to 20 min, but declined at 30 min. Dose-response curve for DAG accumulation induced by A23187 was similar to that for amylase secretion. A23187 augmented CCh-stimulated DAG accumulation and amylase secretion. These results suggest that DAG accumulation is involved in the potentiating effect of A23187 on CCh-stimulated amylase secretion.

Amylases↗

PubMed1990

A protein kinase C-dependent mechanism(s) is involved in atropine-resistant accumulation of diacylglycerol in rat parotid gland.

We investigated the atropine-resistant accumulation of sn-1,2-diacylglycerol (DAG) on stimulation of 1 microM carbachol (CCh) in parotid acinar cells. CCh-induced DAG accumulation was biphasic, peaking at 5 and 20 min. Atropine inhibited two peaks in a dose-dependent manner, but the first peak was inhibited much more than the second one. Atropine (10 microM) completely inhibited both DAG accumulation and the breakdown of phosphatidylinositol 4-monophosphate and 4,5-bisphosphate (PIP2) 5 min after stimulation with CCh. In contrast, the breakdown of PIP2 at 20 min was completely inhibited by 10 microM atropine, but DAG accumulation was not. This atropine-resistant component at 20 min is significantly inhibited by staurosporine, a protein kinase C inhibitor. These results suggest that atropine-resistant accumulation of DAG at 20 min derives directly from other lipids rather than phosphoinositides and is regulated by a protein kinase C-dependent mechanism(s).

Alkaloids↗

PubMed1990

Histopathologic and immunohistochemical studies on alcoholic pancreatitis and chronic obstructive pancreatitis: special emphasis on ductal obstruction and genesis of pancreatitis.

We compared alcoholic pancreatitis (AP), which is thought to be caused by protein plugs, and chronic obstructive pancreatitis (COP), distal to carcinoma, both histopathologically and immunohistochemically. Eighteen cases of AP showed marked and irregularly distributed interlobular fibrosis. The exocrine parenchyma and its immunoreactivity against anti-amylase were rather well preserved, except in the advanced stages of the disease. Protein plugs and pancreatic stones were found. Fifteen cases of COP showed a uniform distribution of inter- and intralobular fibrosis, marked destruction of the exocrine parenchyma, and loss of amylase concentration. Neither protein plugs nor pancreatic stones were found. Anti-collagen immunoreactivity was found in both types of pancreatitis. Although obstruction of the main or small pancreatic ducts is considered to be the principal factor in the genesis of both AP and COP, the histological features of the two diseases are quite distinct from one another. Therefore, duct obstruction caused by protein plugs appears not to be the main factor in the genesis of alcoholic pancreatitis.

Adult↗

PubMed1989

The host range of the pKD1-derived plasmids in yeast.

pKD1 is a 2 mu-like circular plasmid found in the yeast Kluyveromyces drosophilarum that can also stably replicate in Kluyveromyces lactis. We have found a short intergenic region in this genome that appears to be functionally neutral; that is, the introduction of foreign sequences into the single EcoRI restriction site located near one of the inverted repeats did not affect the high stability of the natural plasmid. By introducing a G418 resistance gene at this site, we constructed an autonomous recombinant plasmid. Since this vector did not require cir+ hosts for its stable maintenance, it could be used to examine the transformation host range of pKD1 among all the species belonging to the genus Kluyveromyces. Both species closely related to K. drosophilarum as well as a few other species that are very different in chromosomal GC% could be transformed to yield highly stable transformant clones.

DNA Transposable Elements↗

PubMed1989

Distribution and molecular forms of glucagon-like peptide in the dog.

Using glucagon-like peptide-1 N-terminus and C-terminus directed antisera, we investigated concentration and molecular forms of GLP-1 immunoreactivity (IR) in extracts of various tissues of the dog. GLP-1 IR measured with C-terminus-directed antiserum R2337 (GLP-1 IR-CT) was high in the ileum, appendix, jejunum, colon, and gastric fundus and body. GLP-1 IR measured with N-terminus-directed antiserum R1043 (GLP-1 IR-NT) was high only in the pancreas, and gastric fundus and body. Only GLP-1 IR-CT was found in the hypothalamus, thalamus and medulla oblongata. No immunoreactive materials were detected in the liver, spleen and kidney. Gel-filtration with Sephadex G-50 showed two peaks of both GLP-1 IR-CT and GLP-1 IR-NT, at 10kd and at the position of GLP-1 (1-36 amide) in the pancreatic extract, and one peak at 10kd in the stomach extract. Ileal extracts showed 3 peaks of GLP-1 IR-CT at 10kd, at the position of GLP-1(1-36 amide) and GLP-1(7-36 amide), respectively, but GLP-1 IR-NT was coeluted with GLP-1(1-36 amide). Hypothalamic extracts showed a single peak at the position of GLP-1(7-36 amide). These results suggest that processing of preproglucagon differs in different organs, and that the main GLP-1-related products are a large molecular form and GLP-1(1-36 amide) or GLP-1(1-37) in the pancreas, and GLP-1(7-36 amide) or GLP-1 (7-37) in the ileum and hypothalamus.

Animals↗

PubMed1989

Adenoma and stone formation of the biliary tract in puppies that had choledochopancreatic anastomosis.

A canine model of anomalous choledochopancreatic ductal junction (APCDJ) was produced by choledochopancreatic end to side ductal anastomosis performed in 77 mongrel puppies weighing between 1.5 and 5 kg. Histopathological studies of the biliary tract showed that as the post-operative period became lengthened metaplasia and hyperplasia increased. In nine dogs that lived for over 5 years after the operation, papillomatous adenoma occurred in four (44%), and biliary stones in seven (78%). The histological changes seen in the biliary epithelium of our experimental canine model suggest that bile duct carcinoma may be due to the persistent return of pancreatic juice into the bile duct in patients with APCDJ.

Anastomosis, Surgical↗

PubMed1989

An acute exercise-induced translocation of beta-adrenergic receptors in rat myocardium.

The effect of acute exercise (treadmill running) on rat myocardium beta-adrenergic receptors (beta-AR) was studied. beta-AR was identified in purified sarcolemmal membrane fractions and light vesicle fractions. In control hearts, the number of beta-AR was 21.25 +/- 2.25 and 20.89 +/- 2.89 fmol/mg protein (mean +/- SE) in sarcolemmal membranes and light vesicles, respectively. Immediately after a single bout of dynamic exercise, about 35% of beta-AR was transferred from light vesicles to sarcolemmal membranes (p less than 0.05); concomitantly, isoproterenol-stimulated adenylate cyclase activity also significantly increased in sarcolemmal membranes (p less than 0.05). These results suggest that acute exercise provokes the translocation of beta-AR from a presumably intracellular site (light vesicles) to functional membrane fractions (sarcolemmal membranes) in rat myocardium.

Adenylyl Cyclases↗