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E Okuda

Publications and source records attributed to E Okuda.

18 recordsLinked to original sources
PubMed2001

Crystal structures of recombinant and native soybean beta-conglycinin beta homotrimers.

The crystal structures of recombinant and native beta homotrimers of soybean beta-conglycinin were determined by X-ray crystallography at 2.7 and 2.8 A resolutions, respectively. The crystals of the recombinant and native beta homotrimers belong to space group P21 with cell parameters a = 80.51 A, b = 63.48 A, c = 131.43 A, and beta = 90.01 degrees and with cell parameters a = 82.78 A, b = 69.47 A, c = 125.33 A and beta = 97.22 degrees, respectively. The beta monomers consist of amino-terminal and carboxyl-terminal modules that are very similar to each other and are related by a pseudo-dyad axis. Each module of the beta monomer is subdivided into a core and a loop domain. These structural features of both beta homotrimers are consistent with those of canavalin and phaseolin, which are similar vicilin class proteins. The superposition of the models of the native and recombinant beta monomers shows a root mean square deviation of 0.43-0.51 A for 343 common Calpha atoms within 2.0 A. This result indicates that the N-linked glycans do not influence the final structure of the beta homotrimer. Comparison of the models of beta-conglycinin, phaseolin and canavalin indicates that beta-conglycinin resembles canavalin rather than phaseolin, and that canavalin and phaseolin differ the most among them. The evolutional relationships are discussed.

Amino Acid Sequence↗
PubMed2001

Collagenous fibroma (desmoplastic fibroblastoma) of the palate: a case report.

Collagenous fibroma is an uncommon benign soft tissue lesion that has a wide anatomic distribution. We describe a case of a collagenous fibroma that appeared in the left soft and hard palate of a 37-year-old woman as a 5.0-cm solitary, firm nodule. Microscopically, it was composed of stellate or spindle-shaped cells embedded in hypovascular fibrous stroma. Entrapment of fat was focally identified at the edges. Mitotic figures and tumor necrosis were absent. Tumor cells were immunopositive for vimentin, and a few cells were positive for alpha-smooth muscle actin. Tumor extracellular matrix was immunopositive for type I and type III collagen, as well as for fibronectin. These findings satisfied the diagnostic criteria for collagenous fibroma (desmoplastic fibroblastoma). This case, to our knowledge, represents the first report of this tumor in the mouth. The differential diagnosis of fibrous lesions of the mouth is discussed.

Adult↗
PubMed2001

Detection of p53 gene mutations in human esophageal squamous cell carcinomas using a p53 yeast functional assay: possible difference in esophageal carcinogenesis between the young and the elderly group.

A p53 yeast functional assay, which cannot only detect p53 gene mutations but also can assess p53 gene function, was used to screen for p53 gene dysfunction in human esophageal squamous cell carcinomas. Surgically resected frozen tissues of esophageal squamous cell carcinomas from 57 patients were examined for p53 gene mutation. Because the mean age of the patients diagnosed with esophageal squamous cell carcinoma was 64 years, we classified those who were <65 years of age as the Young Group and classified the others as the Elderly Group. The incidence of p53 gene mutations was 43 of 57 (75%). The incidence of p53 gene mutations observed in the Young Group was significantly higher than in the Elderly Group (P = 0.0007). Alcohol and smoking status did not relate to p53 gene mutation expression. Survival rate after surgery was not significantly associated with the presence of p53 gene mutation. However, in the Young Group with p53 gene mutation, those who had null mutations had a significantly shorter survival than those without null mutations (P = 0.0455). No other clinicopathological factors were associated with p53 gene mutations. Possibly, there may be a difference in esophageal carcinogenesis between the Young and the Elderly groups, because the incidence of p53 gene mutations is different between the two groups. In the Young Group, p53 gene mutation may cause esophageal carcinogenesis, and null mutation for p53 gene is a significant prognostic factor.

Age Factors↗
PubMed2000

Identification of a GPI-anchored type HDL-binding protein on human macrophages.

To identify the HDL3-binding proteins on human macrophages, we examined the involvement of GPI-anchored protein in the binding of HDL3, and tried to purify HDL3-binding protein. From membrane fractions of macrophages, we obtained 80- and 130-kDa HDL3-binding proteins by ligand blotting. Treatment of macrophages with phosphatidylinositol-specific phospholipase C (PI-PLC) significantly decreased the specific HDL3-binding in a dose-dependent manner. Furthermore, treatment with mannosamine, which blocks GPI-anchor formation, decreased specific HDL3-binding in a dose-dependent manner. PI-PLC treatment released from the cells the proteins with an M(r) of 80 kDa, which could also bind HDL3. PI-PLC as well as mannosamine treatment markedly reduced cholesterol efflux from macrophages in association with the decreased HDL-binding. Using HDL3-affinity chromatography, we purified 80-kDa GPI-anchored type HDL3-binding protein. In summary, we demonstrate the implication of 80-kDa GPI-anchored protein in the binding of HDL3 to human macrophages, which might have some role in reverse cholesterol transport.

Binding Sites↗
PubMed2000

[Clinical significance of ambulatory intraesophageal bilirubin monitoring in diagnosis of gastroesophageal reflux].

To evaluate the usefulness of ambulatory intraesophageal bilirubin monitoring in the diagnosis of GER, 38 patients with reflux symptoms and 7 controls were studied, using Bilitec 2000. The % time of bilirubin and acid reflux was less than 5% in all of the controls. In 3 patients of NUD, % time of acid reflux was less than 5%, but that of bilirubin was more than 8% in 2 patients. Acid reflux was found only in 1 of 4 patients who had a history of subtotal gastrectomy, but abnormal bilirubin reflux was found in all of 4 patients. In the other 31 patients, a significant difference was found in the % time of bilirubin reflux by the severity of reflux esophagitis, whereas this difference was not found in that of acid reflux. Intraesophageal bilirubin monitoring is useful in the diagnosis of GER and is essential in patients with hypochlorhydria or minimal reflux.

Adult↗
PubMed1999

Structure-physicochemical function relationships of soybean beta-conglycinin constituent subunits.

Beta-conglycinin, one of the dominant storage proteins of soybean, has a trimeric structure, being composed of three subunits alpha, alpha', and beta. The alpha and alpha' subunits contain the extension regions in addition to the core regions common to all subunits, which are N-glycosylated. Physicochemical functions of recombinant nonglycosylated individual subunits and deletion mutants (alpha(c) and alpha'(c)) lacking the extension regions of the alpha and alpha' subunits were examined at pH 7.6 and 3.7 at low (mu = 0.08) and high (mu = 0.5) ionic strengths. Although individual recombinant subunits exhibited different properties at all conditions, there were some consistencies. Surface hydrophobicities and thermal stabilities of the individual subunits were likely to be conferred by their core regions, and the carbohydrate moieties did not contribute to these properties at any conditions examined here. Solubility at mu = 0.08, heat-induced association, and emulsifying ability remarkably depended on the extension regions and the carbohydrate moieties in addition to the structural features of the core regions. These findings indicate that various end products could be produced by the selection of soybean varieties containing beta-conglycinin with different subunit compositions and suggest a direction for a principle of soybean breeding.

Antigens, Plant↗
PubMed1998

The roles of the N-linked glycans and extension regions of soybean beta-conglycinin in folding, assembly and structural features.

Beta-conglycinin, one of the dominant storage proteins of soybean, is a trimer composed of three subunits, alpha, alpha' and beta. All subunits are N-glycosylated and alpha and alpha' contain extension regions in addition to the core regions common to all subunits. Non-glycosylated individual subunits and deletion mutants (alpha(c) and alpha'(c)) lacking the extension regions of alpha and alpha' were expressed in Escherichia coli. All recombinant proteins were purified to near homogeneity and appeared to have the correct conformation, as judged by CD, density-gradient centrifugation and gel-filtration profiles, indicating that the N-linked glycans and extension regions are not essential for the folding and the assembly into trimers of beta-conglycinin. Density-gradient centrifugation, gel-filtration and differential scanning calorimetry profiles of the recombinant proteins and the native beta-conglycinin indicated that the N-linked glycans and extension regions contribute to the dimension of beta-conglycinin but not to the density and the thermal stability. Comparing the solubilities of the individual subunits with those of deletion mutants, only the alpha and alpha' subunits were soluble at lower ionic strength (mu < 0.25) at around the pH value of the endoplasmic reticulum. This suggests that the extension regions play an important role in the prevention of aggregation in the endoplasmic reticulum in analogy with the N-linked glycans.

Amino Acid Sequence↗
PubMed1993

Granulocyte superoxide anion and elastase release during cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) is known to induce several pathogenic responses in cardiovascular surgery. To explore leukocyte activation during PCB, we investigated superoxide anion (O2-) production by granulocytes in 6 patients undergoing aortocoronary bypass surgery. O2- production was determined with chemiluminescence amplified by a cypridina luciferin analogue. Granulocytes collected from the blood in the arterial site of the CPB circuit were stimulated by phorbol myristate acetate, n-formyl-methionyl-leucyl-phenylalanine, and opsonized zymosan. All the stimulators failed to disclose a significant difference between the magnitude of chemiluminescence during and after CPB. However, significant complement activation was detected, and the plasma level of granulocyte elastase increased gradually during and after CPB. This discrepancy between the unchanged O2- production by stimulated granulocytes and the increase in inflammatory mediators including granulocyte elastase may be due to sequestration of activated granulocytes in extravascular tissues. Namely, it was highly likely that activated granulocytes responsible for the increased plasma elastase level were sequestered and remained outside the blood circulation.

Aged↗
PubMed1993

[Effects of superoxide dismutase administered by coronary sinus retroperfusion on ischemic reperfused canine heart].

The efficacy of superoxide dismutase administered using synchronized coronary venous retroperfusion (SRP) on the extent of myocardial reperfusion injury was studied. Eighteen mongrel dogs were divided into three groups. A control group (group A) consisting of six dogs was subjected to 90 minutes of acute myocardial ischemia via balloon occlusion of the left anterior descending coronary artery (LAD) followed by 6 hours of reperfusion following abrupt deflation of the balloon. In the second group (group B) consisting of six dogs, the LAD was occluded for 2 hours followed by 5.5 hours of reperfusion. In this group, SRP was applied for 30 minutes prior to full reperfusion. In the third group (group C) consisting of six dogs, balloon inflation and deflation was performed in the same manner as group B except the administration of 10 mg/kg of superoxide dismutase (SOD) using SRP. During the occlusion of LAD, severe ischemia was detected by blood flow measurement using color microsphere in all groups. After reperfusion regional blood flow expressed as the percent of preocclusion value in the subendocardial area in three groups were 25% (group A), 38% (group B) and 76% (group C), respectively. There were significant differences between the groups (p < 0.05). Left ventricular function was assessed as global ejection fraction. Although occlusion of the LAD resulted in a reduction of the left ventricular ejection fraction with a similar magnitude in all groups (A; 37 +/- 5%, B; 32 +/- 7%, C; 58 +/- 10%), there was an improvement in groups B and C during reperfusion (p < 0.05). Infarct size was assessed by triphenyl tetrazolium chloride staining.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Short-term treatment with synchronized coronary venous retroperfusion before full reperfusion significantly reduces myocardial infarct size.

The efficacy of short-term synchronized coronary venous retroperfusion (SRP) before full arterial reperfusion was studied in a canine model. A control group (n = 6) was subjected to 90 minutes of occlusion of the left anterior descending coronary artery, which was followed by 6 hours of reperfusion. In another group (n = 6) the left anterior descending coronary artery was occluded for 2 hours followed by 5.5 hours of reperfusion. In this group SRP was applied for 30 minutes before full reperfusion. Myocardial regional blood flow was measured with the use of colored microspheres. During occlusion of the left anterior descending coronary artery, there was severe myocardial ischemia in both groups. Blood flow in the subendocardial area was, however, significantly better in the SRP group (0.51 +/- 0.17 ml/min/gm after 3.5 hours of reperfusion) than in the control group (0.29 +/- 0.16 ml/min/gm) after 4 hours of reperfusion (p less than 0.05). Left ventricular function was assessed as global ejection fraction from a left ventriculogram. Ejection fraction was reduced during ischemia in both groups (control = 38% +/- 3%, SRP = 32% +/- 8%). This dysfunction remained after 4 hours of reperfusion. Infarct size was assessed by means of triphenyltetrazolium chloride staining. The myocardial area at risk was similar in the two groups (control = 33.1% +/- 5.3%, SRP = 30.6% +/- 6.5%). Infarct size, which was expressed as the percent of the area at risk, was significantly smaller in the SRP group (17.2% +/- 14.6%) than in the control group (36.0% +/- 8.1%; p = 0.0197).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Surgical reconstruction of an ascending aortic dissection in Takayasu's arteritis.

A 45-year-old Japanese woman with Stanford type A dissecting aortic aneurysm underwent a reconstructive operation on the ascending aorta. Histopathological diagnosis was Takayasu's arteritis in the chronic and inactive phase. It is very rare that a dissecting aortic aneurysm results from Takayasu's arteritis. Long-standing hypertension and fragility of the aortic media due to disruption of elastic fibers were suspected to cause dissection in the entire aorta in this case.

Aortic Dissection↗
PubMed1990

Evaluation of ZK110841 and AH6809, an agonist and an antagonist of prostaglandin DP-receptors on human platelets, with a PGD2-responsive cell line from bovine embryonic trachea.

ZK110841 and AH6809, an agonist and an antagonist of prostaglandin DP-receptors on human platelets, were evaluated with a fibroblastic cell line from bovine embryonic trachea (EBTr) which specifically responds to prostaglandin D2 (PGD2). ZK110841, equipotent to PGD2, elevated the adenosine 3':5'-cyclic monophosphate (cyclic AMP) level in EBTr cells dose-dependently, being more than 100 fold over the basal level at 1 microM. The half-maximally effective concentration of PGD2 or ZK110841 was 10-30 nM. Increasing concentrations (10(-7)-10(-4) M) of AH6809 (which possesses negligible intrinsic agonist activity) produced parallel shifts to the right of dose-response curves to PGD2 and ZK110841. Schild plots of these data were linear (correlation close to unity) and pA2 values against PGD2 and ZK110841 were calculated to be 6.36 and 6.57, respectively, indicating that AH6809 is a simple and competitive antagonist. These results demonstrate that ZK110841, AH6809 and EBTr cells will be useful for characterization of DP-receptors.

Animals↗
PubMed1990

[Cardiac arrest episodes by cardiomyopathy following total pancreatectomy, a case report].

A 47-year-old man with advanced pancreatic carcinoma underwent total pancreatectomy with resection of the involved portal vein. His postoperative course was complicated by a couple of cardiac arrest episodes. The first episode occurred seven weeks after surgery during drip infusion of CDDP, and later on during the thirteenth week after surgery. There was no apparent cause for those episodes. On both occasions resuscitation was performed adequately. The second arrest was followed by deep inverted T waves on ECG, however, not by elevation of serum CPK-MB. Because of this, myocardial infarction was ruled out. The diagnosis of cardiomyopathy was made possible through the discovery on the echocardiogram of a hypertrophied left ventricle with thick interventricular septum. Then, on catheterization, myocardial squeezing in the left anterior descending coronary artery was noticed. Finally, histological findings concerning the biopsied cardiac muscle led to the same diagnosis. Cardiac arrest in this case seemed to be due to arrhythmia caused by cardiomyopathy. Echo cardiography should be routinely used as part of the examination prior to extended major surgery.

Cardiomyopathy, Hypertrophic↗
PubMed1989

[Surgical repair of vascular ring with aberrant brachiocephalic artery].

The vascular ring causes tracheal and esophageal compression and some cases need the surgical intervention. We report a rare case of vascular ring with aberrant brachiocephalic artery. A nine-month-old boy had suffered from progressing stridor and was admitted to our hospital due to the stridor. The digital subtraction angiography revealed the aberrant brachiocephalic artery which compressed the trachea from anterior aspect. The compression of the trachea was released by tacking forward the aberrant brachiocephalic artery to the sternum with the aid of two stitches. The postoperative course was uneventful. The stridor almost disappeared at one year after the operation.

Aorta, Thoracic↗