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Biomedical subjects

Y Katayama

Publications and source records attributed to Y Katayama.

At least 289 records · Page 16Linked to original sources

Determination of glycated albumin by enzyme-linked boronate immunoassay (ELBIA).

A new affinity method for quantification of glycated albumin by an enzyme-linked boronate-immunoassay (ELBIA) has been established, based on the interaction between boronic acids and the cis-diols of glycated human serum albumin (HSA) trapped by anti-HSA antibody. To evaluate the ELBIA, we first examined the accuracy of the conventional boronate affinity chromatographic (BAC) method. In the BAC method, 8.1-18.9% of nonglycated albumin calibrator nonspecifically bound to the boronate affinity column, values that were regarded as the column blank. In the modified BAC method, therefore, we substracted the column blank value from the measured glycated albumin value to obtain the true value. Because glycated albumin values measured by ELBIA were exactly the same as reported by the modified BAC method, we suggest that the ELBIA results reflect the real status of albumin glycation. We have also developed a fully automated ELBIA system, allowing multiple, rapid, and precise measurements of glycated albumin.

Boronic Acids↗

[A case report of mitral valve replacement using a parasternal incision (minimally invasive cardiac surgery) with pleuritis tuberculosa and after esophagus operation].

A 68-year-old man underwent mitral valve replacement because of mitral regurgitation (prolaps of anterior mitral leaflet) using parasternal incision (Delos M. Cosgrove, minimally invasive surgery). He had been treated as pulmonary tuberculosis previously and had undergone esophagus operation using stomach role reconstruction beneath the sternum four years before the mitral valve procedure. We could not select median-sternotomy as an approach due to stomach role beneath the sternum, nor left posterolateral thoracotomy because of the heavy left-side pleural adhesion. Cardio-pulmonary bypass cannulations were performed through the same incision, because severe atherosclerosis was found at the distal arteries of the abdominal aorta.

Aged↗

[A case of fulminant myocarditis treated by ABIOMED BVS 5000 biventricular support].

Reported is a case of acute fulminant myocarditis with profound circulatory compromise. The patient was supported with biventricular assist devices (BVS 5000 ; ABIOMED Inc., Danvers, Mass.). The patient had remarkable recovery of ventricular function, which allowed for the removal of the device after 269 hours of support and the recovery to the normal quality of life. This case shows the success of mechanical support to treat potentially fatal disease process.

Adult↗

[An adult case of intrathoracic chest wall type lipoma by VATS resection].

A 48-year-old woman without symptoms was pointed out an abnormal shadow on chest X-ray film taken at the mass survey. Image diagnosis led to intrathoracic chest wall type lipoma. The tumor was surgically removed by video assisted thoracoscopic surgery (VATS), and the diagnosis of lipoma pathohistologically. VATS resection was an useful procedure for intrathoracic lipoma because VATS itself must be less invasive and lipoma was not invasive. CT and MRI were useful for evaluation of extent of tumor, but not effective for differential diagnosis of liposarcoma from lipoma. So surgical resection by VATS should be considered, if possible.

Endoscopy↗

[Influence of acute aortic dissection on long-term results of aortic root reconstruction in patients with Marfan's syndrome].

Objective of this study is to evaluate influence of acute aortic dissection on long-term results of aortic root reconstruction in patients with Marfan's syndrome. 19 patients who underwent consecutive aortic root reconstruction between 1985 May to 1998 February were retrospectively reviewed. Patients who associated acute aortic dissection at the time of operation (group D, n = 7) were compared long-term results with those who did not (group non-D, n = 12). Mean follow-up period was 5.1 +/- 3.2 years and longest follow-up term was 12.5 years. In each group early postoperative death was found in one patient. In-hospital mortality in each group were respectively; 14.2% and 8.3%. Late deaths were found in four patients who all belonged to group D, respectively caused by; rupture of thoracoabdominal aneurysm, DIC after subsequent thoracoabdominal surgery, sepsis due to prosthetic valve endocarditis, and sudden death. Actuarial overall survival rate including operative death in D and non-D group were respectively; 0.0 +/- 0% at 6.6 years and 91.1 +/- 8.0% at 12 years. Overall cumulative survival rate was 56.6 +/- 14.0%. Freedom from cardiovascular events, in D and non-D group were respectively; 0.0 +/- 0% at 6.6 years and 60.0 +/- 25.3%, and freedom free form dilatation of residual aorta were respectively; 0.0 +/- 0% at 6.6 years and 100.0 +/- 0% at 12 years. Freedom from subsequent cardiovascular surgery in group D, group non-D and over-all patients were respectively; 0.0 +/- 0% at 6.6 years, 60.0 +/- 25.3% at 12 years and 42.6 +/- 20.2%. In this study, acute aortic dissection in Marfan's syndrome significantly increased late cardiovascular events including dilatation of residual aorta, subsequent aortic surgery and late mortality. On the other hand, excellent long-term results after aortic root reconstruction were found in non-dissection Marfan's syndrome. Considering high incidence of late dilatation of residual aorta, simultaneous total arch replacement with aortic root reconstruction is recommended in acute dissecting Marfan's syndrome. Whereas, preventive simultaneous arch replacement is not required in non-dissecting Marfan's syndrome because of less postoperative vascular events.

Acute Disease↗

[Re-do surgery with minimally invasive cardiac surgery (MICS): mitral valve replacement 6 years after open mitral commissurotomy].

A 60-year-old man, who had undergone open mitral commissurotomy 6 years ago, underwent re-do surgery (mitral valve replacement) with minimally invasive cardiac surgery (MICS), using lower partial sternotomy to the height of the right side second intercostal space. Cannulation of the heart was carried out placing a cannula directly into the superior vena cava and a second cannula in the inferior vena cava via the right atrium. Arterial return was through the ascending aorta. Cardioplegia was administered directly into the ascending aorta with intermittent perfusion. Valve replacement was performed by opening directly right side left atrium.

Cardiac Surgical Procedures↗

[Endopyelotomy with Acucise for secondary ureteropelvic junction obstruction: report of a case].

We report a case of successful endopyelotomy using the Acucise cutting balloon device for secondary ureteropelvic junction obstruction (UPJO). A 23-year-old man was hospitalized with the chief complaint of left lumbago and left hydronephrosis due to left UPJO. He underwent antegrade endopyelotomy with a nephroscope and open pyeloplasty. However, left lumbago and hydronephrosis did not show improvement. Acucise endopyelotomy was performed under epidural anesthesia. The operative time was 55 minutes and the hospital stay after the operation was 4 days. There were no operative complications and 3 months later, the operative results were satisfactory as determined by drip infusion pyelography and the disappearance of the lumbago.

Adult↗

[Thoracoabdominal aortic repair without using assisted bypass].

A 41-year-old man, who had undergone descending aortic repair following rupture of the DeBakey type III aortic dissection, underwent thoracoabdominal aneurysm repair 1 year after the first surgery. The operation was performed by partial-clamping and single crossclamping without using assisted bypass or shunt, in order to minimize bleeding ensuing the re-thoracotomy and dissection between lung and the graft.

Adult↗

[Endothelial expression of adhesion molecules].

The adhesion molecule in the vascular endothelial cell is outlined, we reports on our result about the relation etc. among the adhesion molecule, the acute myocardial infarction, and the insulin resistance, and utility as the clinical examination is described the time. This study measured the serum concentrations of circulating adhesion molecules by sandwich enzyme-linked immunosorbent assay with the acute myocardial infarction (AMI) and the insulin resistance, and the expression of adhesion molecules on lymphocyte were analyzed by flow-cytometry. Only ELAM level in AMI disease were significantly higher (p < 0.01) than controls. sELAM has the possibility of the foresight marker of the AMI diagnosis. The correlation of SSPG value of index of the insulin resistance and IL-6, sELAM-1, and sICAM-1 takes part in condition when the immune reaction through cytokine and the adhesion molecule administered insulin. The relation between insulin and the adhesion molecule was suggested from the result of using the vascular endothelial cell. Endothelial cells are stimulated dramatically and increase the appearance of adhesion molecules on surface of the cell by the interactions with leukocytes. In these interactions with AMI and the insulin resistance, ELAM, ICAM-1 and VCAM-1 are suggested to play the most important role.

Cell Adhesion Molecules↗

[Sampling and quality assurance].

For the efficient operation of clinical laboratories, automated biochemical analyzers have been improved. Large rapidly analyzing and multichannel analyzers, and small or mid-sized multiple component analyzers are now commercially available and widely use. Such apparatus might require only a small amount of specimen and reagent to assay one analyte. Performance has been increased annually. In this report, we discuss whether this performance, sampling of specimen, sampling of reagent, and mixing effect of reaction mixture or diluted specimen affect the accuracy and precision of measurements.

Autoanalysis↗

[Relationship between apoptosis-related markers and cardiomyopathy].

Increasing interest has been focused on the role of apoptosis in pathogenesis of idiopathic cardiomyopathy. Interactions between soluble Fas, tumor necrosis factor-alpha (TNF-alpha) and Fas ligand have been reported to play a pivotal part in signal transduction of apoptosis. Thus, we measured serum levels of apoptosis-related markers, namely sFas, TNF-alpha and two types of its receptor TNF-RI and TNF-RII in the patients with idiopathic cardiomyopathy. Serum level of TNF-alpha was higher in dilated cardiomyopathy (DCM) group as well as in hypertrophic cardiomyopathy (HCM) group than in the control group. There were significant correlation among TNF-alpha, TNF-RI and TNF-RII in DCM group. However, only slight tendencies among these parameters in HCM group, indicating different pathogenesis from DCM. No transcardiac production of TNF-alpha, TNF-RI and TNF-RII was found in cardiomyopathies in the present study. These data suggested that apoptosis-related markers could be used for the detailed classification of cardiomyopathy. Furthermore, the simultaneous measurement of receptors and their ligands of apoptosis-related markers might underscore clinical implications.

Apoptosis↗

Effect of long-term administration of ethyl eicosapentate (EPA-E) on local cerebral blood flow and glucose utilization in stroke-prone spontaneously hypertensive rats (SHRSP).

The objective of this study was to determine the effect of ethyl eicosopentate (EPA-E) on local cerebral blood flow (1-CBF) and local glucose utilization (1-CGU) in specific regions of the brain in stroke-prone spontaneously hypertensive rats (SHRSP). EPA-E (100 mg/kg body weight) or saline was orally administered to 8-week-old SHRSP. L-CBF and 1-CGU in the EPA-E-treated, saline-treated, and 8-week-old control rats were measured autoradiographically using 14C-iodoantipyrine and 14C-deoxyglucose (Sakurada's and Sokoloff's methods). The 1-CBF of the saline-treated group decreased significantly with age in all areas measured. EPA-E treatment alleviated the age-dependent decrease in 1-CBF in all areas, especially those in the basal ganglia. The 1-CGU of the saline-treated group did not change with age, however EPA-E treatment increased 1-CGU in all areas measured, though the changes were not significant. EPA-E ameliorated the decrease in cerebral blood flow and improved glucose metabolism in SHRSP suffering from severe hypertension. These results suggest that EPA-E may be useful in the prevention of stroke.

Animals↗

Ischemic tolerance phenomenon from an approach of energy metabolism and the mitochondrial enzyme activity of pyruvate dehydrogenase in gerbils.

The objective of this study was to determine if the pretreatment with a sublethal ischemic insult, which has been shown to protect against delayed neuronal death, effects the recovery of energy metabolites or alters the activity of pyruvate dehydrogenase (PDH) following transient cerebral ischemia. Gerbils were pretreated with a sublethal ischemic insult, 2 min of bilateral common carotid artery occlusion, and 24 h later given a 5-min lethal ischemic insult. Animals were reperfused for 0, 10, or 60 min, or 1, 3 or 7 days. Brain metabolites, ATP, PCr, and lactate, and PDH activity were measured in the cortex and the hippocampal CA1 region. The pretreatment had no effect on ATP and PCr depletion or on lactate accumulation after the 5-min insult, nor on their recovery up to 1 day reperfusion, although there was a difference in the lactate levels of the non-pretreated and the pretreated gerbils after 10 min reperfusion. The pretreatment also had no effect on PDH activity during ischemia and reperfusion in either region. However, at 3 days reperfusion the non-pretreated animals exhibited a secondary decrease in ATP levels in the hippocampus. At 7 days reperfusion, ATP levels in the hippocampus of both the pretreated animals and the non-pretreated animals were significantly decreased compared to controls. Additionally, the level of ATP in the non-pretreated group was significantly lower than that in the pretreated group. The pretreatment with a sublethal ischemic insult did not effect the initial recovery of metabolites or the activity of PDH following transient cerebral ischemia. However, it protected against the secondary decrease of ATP levels in the hippocampus. Thus, the induction of ischemic tolerance is not caused by a reduction in metabolic impairment during the secondary insult.

Adenosine Triphosphate↗

Wild-type, but not mutant-type, p53 enhances nuclear accumulation of the NS3 protein of hepatitis C virus.

By using vaccinia virus-T7 hybrid expression system, subcellular localization of the NS3 protein of hepatitis C virus was studied. Full-size NS3 (NS3F) and a carboxy-terminally truncated form (NS3 deltaC) were localized in the cytoplasm and the nucleus when expressed alone. However, NS3F and NS3 deltaC, but not amino- and carboxy-terminally truncated form (NS3 deltaN deltaC), were each co-localized with wild-type p53 almost exclusively in the nucleus upon co-expression. The wild-type p53-induced nuclear accumulation of NS3F was inhibited only partially by NS4A. When co-expressed with mutant-type p53, NS3F and NS3 deltaC were each co-localized with it exclusively in the cytoplasm. Taken together, the present results suggest that wild-type p53 enhances nuclear accumulation of NS3F and NS3 deltaC through the involvement of their amino-terminal sequences even in the presence of NS4A, and that mutant-type p53 inhibits their nuclear, and enhances their cytoplasmic, accumulation.

Base Sequence↗

Hemodynamic depression and microthrombosis in the peripheral areas of cortical contusion in the rat: role of platelet activating factor.

Cerebrovascular damages leading to subsequent reductions in regional cerebral blood flow (rCBF) may play an important role in secondary cell damages following traumatic brain injury (TBI). Recent studies have demonstrated that rCBF markedly decrease in experimental model of TBI (e.g. fluid percussion injury, acute subdural hematoma, contusion). However, precise mechanisms underlying post-traumatic CBF reduction remain unclear. In the present study, the rCBF changes and microthrombosis formation were investigated in a cortical contusional model in rats, and the effects of etizolam (platelet activating factor antagonist) on microthrombosis were tested. The rCBF in the peripheral areas increased transiently, and decreased to ischemic level 3 hours post- injury. The histological examinations revealed microthrombosis formation in the contused area, extending from the center to the peripheral areas within 6 hours post-injury. The rCBF decrease and the contusion necrosis volume were significantly attenuated by etizolam administration. These results indicate that platelet activating factor is involved in microthrombosis formation and hemodynamic depression, and resultant ischemic damages within areas surrounding the contusion.

Animals↗