Biomedical subjects

Y Sudo

Publications and source records attributed to Y Sudo.

At least 109 records · Page 6Linked to original sources

PubMed1995

[Successful surgical repair of subepicardial aneurysm developing as a late complication of mitral valve replacement].

A 60-year-old man who undergone uneventful mitral valve replacement 9 years and 5 months previously was referred to us because his chest roentgenogram showed rapidly growing abnormal shadow. Two-dimensional echo cardiography revealed a left ventricular pseudoaneurysm. Emergent surgery was performed under the cardiopulmonary bypass. The aneurysm, which arose posteriorly from the base of the left ventricle, had a thin wall that could be separated from the pericardium. It was therefore diagnosed to be a subepicardial aneurysm. Examination of his previously implanted mitral prosthesis (a Duromedicus valve) revealed that the mitral orifice was partially occluded by a thrombus. The Duromecicus valve was therefore removed, and the ruptured left ventricular wall was closed from both outside and inside. A St. Jude Medical valve was then placed in the mitral position. Pseudoaneurysm or subepicardial aneurysm formation is a possible late complication after mitral valve replacement. Physicians and surgeons should be aware of this late complication in patients who had undergone mitral valve replacement because it urgently requires surgical correction.

Cardiopulmonary Bypass↗

PubMed1995

[Long-term results of Bentall and modified Bentall procedure in aortic root replacement].

Between 1976 and 1994, sixteen patients who had annulo-aortic ectasia required aortic root replacements. Ten patients had annulo-aortic ectasia and 6 patients had aortic dissections. The operative techniques included Bentall procedure in 6, Cabrol procedure in 3 and Carrel patch procedure in 7. No hospital death was noted, although there were three major late complications and two of them died. First patient having Bentall procedure died from acute myocardial infarction because of the compressed left coronary artery by the wrapping aneurysmal wall. Second patient having Bentall procedure had enlargement of residual false lumen. Third patient having Cabrol procedure developed false aneurysm at the ostial anastomosis and died of cerebral haemorrhage. In contrast, no late complication has been noted in patients having Carrel patch procedure. Although further long-term follow-up is required, our experience suggests that Carrel patch procedure has less late complication.

Adult↗

PubMed1995

Ligand-induced growth cone collapse: amplification and blockade by variant GAP-43 peptides.

Growth cones are powerful amplifiers for signals from the microenvironment. Their collapse can be triggered by cell surface components of myelin and brain membranes, as well as by soluble ligands, including neurotransmitters. GAP-43 is a protein concentrated on the inner surface of the growth cone membrane. Assayed in isolation, it interacts with the heterotrimeric protein, G(o), and in oocytes it amplifies the effects of ligand-triggered G protein activation. We wished to examine whether GAP-43 serves to amplify signals at the growth cone. The G(o) stimulating region of GAP-43 is encoded in the 10 amino acids (MLCCMRRT-KQ) of the first exon. We examined the effect of this peptide upon chick dorsal root ganglion growth cone collapse and neurite retraction triggered by brain membranes or myelin, as well as by serotonin. We find that application of the GAP-43 1-10 peptide amplifies the effects of all three ligands. The amplification is greater when GAP-43 1-10 is injected intracellularly. Peptides with amino acid substitutions for the two cysteine residues manifest parallel changes in growth cone collapse and G(o) stimulation. In particular, tyrosine or methionine substitutions cause the peptide to inhibit G(o) and to block induced growth cone collapse. The GAP-43 peptides therefore regulate the sensitivity of growth cones to extrinsic signals. The modified peptides serve as a starting point for the design of reagents to enhance CNS regeneration.

Amino Acid Sequence↗

PubMed1995

[Report of a case of bilateral adrenal teratoma with CA19-9 production].

Reports of adrenal teratomas in adults are rare, and all of adrenal teratomas which were reported in the literature were found in unilateral adrenal gland. This is the first reported case of CA19-9 producing huge teratomas found in bilateral adrenal gland. Twenty-two year-old woman was hospitalized for an episode of abdominal growing mass and an abnormality of high CA19-9 serum level. Operatively, bilateral adrenal tumors were removed, and the weights of right one and left one were 3976g and 618g, respectively. Histological diagnosis of both tumors was mature teratoma. Immunohistochemical findings revealed CA19-9 was produced from intestinal epithelium in teratoma.

Adrenal Gland Neoplasms↗

PubMed1995

[Emergency coronary bypass grafting for failed percutaneous transluminal coronary angioplasty].

From January 1992 through September 1993, 545 patients underwent PTCA in Asahikawa City Hospital. 6 patients (1.1%) required emergency CABG. Perfusion catheter was placed in three patients. This catheter allowed for immediate and temporary reperfusion of blood to the ischemic myocardial tissue. And it provided us with time and a patient in stable condition. This technique reduce PMI, morbidity, and mortality in emergency CABG after failed PTCA.

Aged↗

PubMed1995

[A case of aortic bicuspid valvular endocarditis with congenital left ventricular diverticulum].

A 29-year-old man had a prolonged fever and painful Osler's nodes on his right foot. The aortic valve was bicuspid with vegetation mass and the left ventricular diverticulum was additionally present connecting with the left ventricular outflow tract. An operation was performed after intravenous administration of antibiotics for 3 weeks. The aortic bicuspid valve and the vegetation were removed and replaced by an artificial valve (SJM-HP 19 mm). The left ventricular diverticulum was resected. The echocardiographic findings correlated well with the intraoperative observation.

Adult↗

PubMed1995

Serum levels of endogenous and exogenous granulocyte colony-stimulating factor after autologous blood stem cell transplantation.

Although the administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) enhances myeloid engraftment and reduces infectious morbidity after autologous and allogeneic bone marrow transplantations, the effect of rhG-CSF on neutrophil recovery in autologous blood stem cell transplantation (ABSCT) is controversial. We previously demonstrated that a low dose, delivered subcutaneously, of rhG-CSF (50 micrograms/m2) accelerates neutrophil recovery in ABSCT, but the optimal dosage of rhG-CSF is not known. To elucidate the effect of rhG-CSF on neutrophil recovery, we determined serum levels of endogenous and exogenously administered G-CSF in 24 patients receiving ABSCT. Of these, five received bolus subcutaneous injection of 50 micrograms/m2 rhG-CSF, 10 received 150 micrograms/m2, and nine received no rhG-CSF. Endogenous G-CSF levels rose immediately after ABSCT, and an inverse correlation was found between the serum level of G-CSF and the absolute neutrophil count (r = -0.73, p < 0.01). The pre-dose level in patients receiving rhG-CSF rose gradually, reaching a maximum between days 3 and 6. The level gradually decreased as the neutrophil count began to rise, even through administration of the same dose of rhG-CSF continued. Pharmacokinetic data showed that the half-life of elimination of G-CSF (t1/2) exceeded 15 hours during severe neutropenia but decreased during the recovery of neutrophils. These observations suggest that neutrophils provide a negative feedback mechanism for clearing G-CSF from the circulation. Pre-dose levels of G-CSF in patients receiving 50 micrograms/m2 rhG-CSF reached 10 ng/mL, equivalent to the concentrations used in clonogenic assay in vitro to stimulate myeloid progenitor cells.

Adolescent↗

PubMed1994

Beta 1-integrin-mediated adhesion of melanoma cells to the propolypeptide of von Willebrand factor.

Cell-adhesion activity of the bovine propolypeptide of von Willebrand factor (pp-vWF) was assessed by means of an in vitro assay with several cell lines of both normal and tumor-cell origin. pp-vWF promoted adhesion and spreading of B16 mouse melanoma cells and G-361 human melanoma cells. However, it could not induce adhesion of any other cell lines tested including endothelial cells, normal fibroblasts, and tumor cells of sarcoma, carcinoma, neuroblastoma and leukemia origin. A monospecific polyclonal antibody against pp-vWF, but not against fibronectin, laminin, and von Willebrand factor (vWF), completely blocked the pp-vWF-mediated adhesion, indicating that the cell adhesion was due to the pp-vWF molecule and not due to possible contamination of these three well-known adhesive proteins. The cell-adhesion activity was also observed with human pp-vWF and, furthermore, the adhesion to both bovine and human pp-vWF was not affected by a peptide containing the Arg-Gly-Asp sequence while the peptide abolished the cell adhesion to vWF. The adhesion was completely dependent on Mg2+ and inhibited by Ca2+. Inhibition by an anti-(beta 1 integrin) mAb (4B4) indicates that the receptor for this protein belongs to the beta 1-integrin family. A monoclonal antibody (TC4) among several antibodies directed against bovine pp-vWF inhibited the B16 adhesion to immobilized pp-vWF. The epitope for this monoclonal antibody lies in a central 8-kDa portion of pp-vWF, suggesting that this region is important for the cell-adhesion activity. This idea was supported by the finding that purified 8-kDa fragment promoted adhesion of B16 cells in a concentration-dependent manner. As pp-vWF shows unique cell-type specificity in its adhesion activity, which is completely different from that of fibronectin, laminin, vWF and collagen, it may be a novel type of adhesive glycoprotein that utilizes a beta 1-integrin receptor.

Amino Acid Sequence↗

PubMed1994

Production of a monoclonal antibody 14A20 that reacts with a 220-kDa protein in the islet cells.

To study the target antigens of the islet cell cytoplasmic antibodies (ICA), we tried to make a monoclonal islet cell antibody. We made a monoclonal antibody 14A20 (IgM, kappa) that reacted strongly with Wistar and BB rat islet cells and weakly with pancreatic acinar cells. The immunoreactivity of the 14A20 was also found to react extensively in neuroendocrine cells. Immunostaining showed a granular pattern in both neurons and islet cells. Chemical and enzymic studies revealed that the antigen has the property of a protein. We compared immunoreactivity of the monoclonal antibody 14A20 with anti-insulin, -glucagon or -somatostatin antibodies. The antigen recognized by the monoclonal antibody 14A20 was equally present in the alpha, beta, and delta cells of islet, which mimicked the immunoreactivity of the ICA in the pancreas. The recognized protein had a relative molecular weight of 220,000, indicating that it is different from the previously identified target antigen of the ICA.

Animals↗

PubMed1994

Two glucose-signaling pathways in S14 gene transcription in primary hepatocytes: a common role of protein phosphorylation.

Transcription of the rat S14 gene is induced in response to increased carbohydrate metabolism in the liver. Because carbohydrate-induced changes in lipogenesis are mediated in part by changes in phosphorylation of multiple proteins, we investigated the role of protein phosphorylation on transcriptional regulation of the two carbohydrate response elements, a thyroid hormone receptor-independent carbohydrate response element and a thyroid receptor-dependent glucose response element located up-stream of the S14 gene. S14 reporter constructs were transiently transfected into rat primary hepatocytes and incubated with the protein or phosphatase inhibitor okadaic acid calyculin-A, or one of several protein kinase activators. Low dose okadaic acid blocked glucose induction from both elements without inhibiting glucose metabolism. Calyculin-A, a preferential phosphatase-1 inhibitor, only blocked the glucose response when glucose metabolism was inhibited. The protein kinase-C activator, 12-myristate 13-acetate, did not change the glucose responses, whereas the protein kinase-A activator, 8-(4-chlorophenylthio)cAMP, inhibited S14 transcription by inhibiting glucose metabolism. In contrast, the calcium ionophore A23187, a calmodulin kinase activator, mimicked the effect of low dose okadaic acid, but had no effect on glucose metabolism. We conclude that protein phosphatase-2A and calmodulin kinases may be involved in the glucose signaling pathway of the S14 gene. A similar phosphorylation step may be involved in the two distinct glucose response pathways.

Animals↗

PubMed1994

[Monitoring of electroencephalogram during the operation under the extracorporeal circulation].

Generally speaking, it is difficult to know the occurrence of brain complication until the patient becomes awake from anesthesia. But if we can detect the occurrence of of brain complication during the operation, we can start its therapy even during the operation. In order to detect the occurrence of brain complication during the operation under extracorporeal circulation (ECC), we monitored intraoperative electroencephalogram (EEG). Since June 1992, forty-two patients were operated on using ECC. Usual ECC was applied in 39 cases (Group-A), and circulatory arrest with retrograde cerebral perfusion was applied in remaining three cases (Group-B). We studied the amplitude of EEG using actual value (by Fujimori method), and compressed EEG acquired by slow-paper-feed recording. In terms of the frequency of EEG, we studied compressed spectral array (CSA). In Group-A, there was no brain complication identified after operation. Actual values of amplitude were 23 +/- 4.0 microV (before ECC), 19 +/- 4.0 microV (during ECC), 23 +/- 4.9 microV (after ECC). There was a significant decrease (p < 0.001) of amplitude during ECC compared with that before ECC. The ratio of amplitude during ECC to that before ECC (D/B ratio) was 0.82 +/- 0.16. The ratio of amplitude after ECC to that before ECC (A/B ratio) was 1.01 +/- 0.15. According to compressed EEG, it was observed that the amplitude changes following the up-down of esophageal temperature. In CSA, influence of esophageal temperature on the power spectrum of alpha and delta wave band was recognized. In Group-B, there was one brain complication identified after operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Effect of milk on absorption of norfloxacin in healthy volunteers.

The authors studied the effect of milk on the bioavailability of norfloxacin in six healthy male volunteers in a randomized crossover trial. After an overnight fast, 200 mg of norfloxacin was given with 200 mL of water or milk. Area under the curve (AUC) of norfloxacin with milk was significantly (P < 0.01) smaller than that with water. The mean peak serum concentration was decreased to 60% after oral administration of norfloxacin with milk (P < 0.01). The apparent volume of distribution at central compartment (Vc/f) value of norfloxacin was significantly (P < 0.05) increased with milk. Milk exhibits a clinically significant effect on norfloxacin absorption.

Adult↗

PubMed1993

The thyroid hormone receptor can unmask a glucose response in the S14 gene.

The rat S14 gene is synergistically regulated by thyroid hormone and carbohydrates. The 5'-flanking region of this gene contains both carbohydrate and thyroid hormone response elements (TREs). We recently located the carbohydrate response element (CHORE) between -1583 and -1069 bases from the start site of transcription that is required for glucose induction of this gene. We have now studied the relationship between the effects of CHORE, TREs, and thyroid hormone receptor on the carbohydrate regulation of transcription. We used a transient cotransfection assay with a plasmid containing 5 kilobases (kb) of the up-stream region from the S14 gene ligated to a luciferase reporter and a thyroid hormone receptor expression vector. Unliganded thyroid hormone receptor reduced the response of the reporter to glucose. Ligand-bound thyroid hormone receptor significantly enhanced the glucose response from the 5-kb promoter. While deletion of the CHORE (5-kb delta CHORE) from the 5-kb S14 promoter eliminated the glucose response without cotransfection of the thyroid receptor, deletion of the CHORE did not affect the glucose response when both thyroid hormone receptor was cotransfected and thyroid hormone was present. However, deletion of the TREs (-3261 to -2110) from the 5-kb delta CHORE construct abolished the effect. These data suggest that the thyroid hormone receptor functions as or in association with a trans-acting glucose response factor. The site of interaction between thyroid hormone and glucose is localized to an area of the gene that is different from the previously described CHORE.

Animals↗

PubMed1993

Location of a glucose-dependent response region in the rat S14 promoter.

The rat S14 gene provides an excellent model to examine the DNA sequences associated with carbohydrate regulation of hepatic gene transcription. We constructed internal deletions within 5 kilobases of the 5'-up-stream region and ligated these to a luciferase reporter gene. The constructs were transfected into primary hepatocytes and pancreatic HIT cells. In hepatocytes, an increase in the medium glucose concentration led to a parallel increase in endogenous mRNA S14 content and transfected luciferase reporter activity driven by 5 kilobases of the S14 promoter. Internal deletions of several sequences from -2706 to -285 each led to a decrease in glucose-stimulated activity, suggesting that multiple elements are necessary for the transcriptional response to glucose. Deletion from -1583 to -1069 nearly abolished the glucose effect in both cell types and delineated the carbohydrate response element (CHORE). The CHORE deletion was specific for glucose, because it did not alter the response to thyroid hormone, another known regulator of this gene. Although the CHORE sequence did not confer glucose activation to either a heterologous promoter or the basal S14 promoter (bases -285 to +19), a 5-fold enhanced response was observed when two copies of the CHORE were ligated to the first 2110 basepairs of the S14 promoter. The results suggest that the CHORE contains a carbohydrate regulatory element and operates as an enhancer in concert with other sequences within the S14 gene.

Animals↗

PubMed1993

[Aortic valve replacement for narrow aortic ostium, supraannular insertion at noncoronary sinus with Bjrk-Shiley valve].

Fifteen patients with small aortic annuli underwent aortic valve replacement either isolated or combined with other procedures. All patients had aortic valve replacement with Björk-Shiley prosthesis larger than the aortic annulus. The prosthesis was sutured in a supraannular position in the area corresponding to the noncoronary sinus. There was no hospital and late death. In the long term follow up, 21 mm prosthetic gradients by doppler method ranged from 17 to 43 (29.9 +/- 7.3) mmHg in patients with supraannular aortic valve replacement and from 20 to 45 (27.4 +/- 7.1) mmHg in patients with standard aortic valve replacement, which showed statistically no significant difference. Because this technique allows the insertion of prosthetic valves one sizes larger than the size of aortic annulus, it will produce stable hemodynamic result. As a consequence, those procedure such as transannular patch reconstruction will be avoided.

Adult↗

PubMed1993

[A case of stunned myocardium: dual SPECT findings similar to acute myocardial infarction (AMI)].

Emergent cardiac catheterization was performed on a 70-year-old female patient who was admitted for further evaluation of acute myocardial infarction. Coronary angiography didn't reveal any significant stenotic lesion, but levogram showed extensively abnormal contractility around the center of the apex region. On the second hospital day, 99mTc-PYP/201TlCl dual SPECT gave findings similar to those found in acute myocardial infarction, but myocardium--released enzyme stayed within the normal range. Two weeks after, 201TlCl myocardial scintigraphy showed disappearance of the perfusion defect, and normal contractility was observed on the levogram of the chronic phase. Since this case was clinically denied to be myocardial infarction, it was considered a typical case of stunned myocardium which showed prolonged left ventricular abnormal contractility with transient myocardial ischemia. This is a case suggestive for estimations of myocardial reversibility in patients with myocardial perfusion and metabolic disorder in dual SPECT.

Aged↗

PubMed1993

[A case of Behçet's disease associated with ascending aortitis and aortic regurgitations--surgical repair with Cabrol's method].

This is the case report of a 52 years old female patient operated with Cabrol's method for the inflammatory lesion of the aortic root in Behçet's disease. The diagnosis of incomplete type of Behçet's disease had already been established 4 years ago and the patient had been taking regular check-up since then. About one year ago, newly developed cardiac murmur compatible with aortic regurgitation was detected and the patient was subsequently referred to us for the surgical repair. Although aortic valve replacement (AVR) was attempted first, Cabrol's method was lastly chosen, since inflammatory features on the surface of the ascending aorta associated with slight aortic annular dilatation were observed during the procedure and it was easily anticipated that these might induce postoperative paravalvular leakage and pseudoaneurysm, if AVR were performed. Two weeks after the surgery, the patient developed aphthous stomatitis associated with several other evidences of inflammatory recurrence, the steroid therapy was instituted with prednisolone. Post operative progress was uneventful and the patient has been completely well at the 6th month after the surgery. In conclusion, it is strongly recommended the Cabrol's method should be chosen to prevent post operative unfavourable complications, whenever any evidence of inflammation is observed around the aortic root area.

Aorta, Thoracic↗

PubMed1992

Type II collagen-induced murine arthritis: induction of arthritis depends on antigen-presenting cell function as well as susceptibility of host to an anticollagen immune response.

Two sets of ((resistant x susceptible) F1----parent) and (parent----F1) chimeric mice were prepared. In the chimeric combinations involving BALB/c and DBA/1 mice, all (F1----F1) chimeras developed arthritis as well as potent anticollagen responses after immunization with collagen, whereas all (F1----BALB/c) and (BALB/c----F1) chimeras induced neither arthritis nor immune responses. This type of F1 T cells could be activated with APC from DBA/1 but not from BALB/c mice. Thus, the failure of the [F1 in equilibrium with BALB/c] chimeras to mount anticollagen responses was due to a defect at the APC level. Another arthritis-resistant strain, C57BL/6, exhibited adequate APC function, but reduced T cell responsiveness, representing an intermediate responder. In the chimeric combinations involving C57BL/6 and DBA/1 mice, (F1----F1) and (C57BL/6----C57BL/6) chimeras developed very high and very low incidence of arthritis, respectively. (C57BL/6----F1) chimeras developed an appreciable incidence of arthritis under conditions in which this group of chimeras generated intermediate levels of anticollagen responses. In contrast, (F1----C57BL/6) chimeras developed low incidence of disease despite induction of strong responses. Moreover, cells from collagen-immunized (F1----C57BL/6) chimeras, when transferred into T cell-depleted B cell mice of F1 or C57BL/6 strain, produced comparable immune responses in both groups but induced much more severe arthritis in F1 than in C57BL/6 recipients. These results indicate that: i) two types of arthritis-resistant strains can be identified, each of which has anticollagen APC defect as a low responder and reduced T cell responsiveness as an intermediate responder and ii) a discrepancy between the degree of anticollagen responses and clinical arthritis is attributed to the differential susceptibility to anticollagen immune responses.

Animals↗