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Biomedical subjects

Y Ueda

Publications and source records attributed to Y Ueda.

At least 91 records · Page 5Linked to original sources

Effects of ischemic preconditioning on contractile and metabolic function during hypoperfusion in dogs.

We examined the effects of ischemic preconditioning (i.p.) on metabolic and contractile function during coronary hypoperfusion in dogs. After the left anterior descending coronary artery (LAD) was occluded for 5 min (i.p.) and reperfused for 10 min, coronary blood flow (CBF) of the LAD was decreased to 33% of the control. I.p. increased (P < 0.05) lactate extraction ratio and the pH of coronary venous blood and decreased (P < 0.05) myocardial oxygen consumption and fractional shortening during hypoperfusion compared with those in the control group, although i.p. did not change the endocardial-to-epicardial blood flow ratio of the regional myocardium during hypoperfusion. I.p. increased (P < 0.05) the adenosine levels in coronary venous blood during hypoperfusion. I.p. increased (P < 0.05) myocardial ecto-5'-nucleotidase activity. Administration of 8-sulfophenyltheophylline or alpha, beta-methyleneadenosine 5'-diphosphate blunted the i.p.-induced changes in metabolic and contractile parameters during hypoperfusion. These results suggest that i.p. reduced the severity of anaerobic myocardial metabolism of ischemic hearts by increasing the adenosine levels via an extracellular pathway.

5'-Nucleotidase

Possible role of nitric oxide in IgE-mediated allergic cutaneous reaction in mice.

The role of nitric oxide (NO) in the development of allergic cutaneous reactions in mice was investigated. A biphasic cutaneous reaction composed of an immediate-phase edema and a late-phase edema was evoked by epicutaneous application of 2,4-dinitrofluorobenzene on the ear of mice passively sensitized with mouse anti-dinitrophenol monoclonal IgE. Two NO synthase inhibitors, L-NG-nitroarginine methyl ester (L-NAME) and NG-monomethyl-L-arginine, significantly inhibited both phases of the IgE-mediated biphasic cutaneous reaction. Simultaneous treatment with L-arginine attenuated the inhibitory effect of L-NAME. An NO donor, 3-morpholinosydononimine-N-ethylcarbamide, caused a potent edematous reaction in the mouse ear. Furthermore, L-NAME inhibited the cutaneous reactions caused by both interleukin-1beta and tumor necrosis factor-alpha, putative mediators of the late-phase edema in the biphasic cutaneous reaction. These results indicate that a gaseous mediator, NO, participates, at least in part, in the development of ear edema in the IgE-mediated biphasic cutaneous reaction in mice.

Animals

Classification of Lactobacillus helveticus strains by immunological differences in extracellular proteinases.

Polyclonal antibodies against an extracellular proteinase of Lactobacillus helveticus CP53 were raised. The antibodies reacted with a 170-kDa enzyme with activity and a 53-kDa protein that seemed to be a degradation product of the 170-kDa proteinase from results of immunoblotting. The antibodies reacted also with a 45-kDa extracellular proteinase of L. helveticus CP790. However, monoclonal antibodies to the CP790 proteinase did not react with the proteinase of L. helveticus CP53. Seventeen strains of L. helveticus were tested for immunological reactivity with the two kinds of antibodies. The strains all had the same reactivity as either strain CP53 or strain CP790. Eleven strains with the 45-kDa proteinase were identified as L. helveticus biovar jugurti because they did not ferment maltose, four other strains with the 170- and 53-kDa proteins were identified as L. helveticus biovar helveticus because they fermented maltose. The remaining two strains dit not fit this pattern; they had both the 170- and 53-kDa proteins, but classification by their sugar utilization showed them to be L. helveticus biovar jugurti.

Animals

Accumulation of carbonyls accelerates the formation of pentosidine, an advanced glycation end product: carbonyl stress in uremia.

Advanced glycation end product (AGE) formation is related to hyperglycemia in diabetes but not in uremia, because plasma AGE levels do not differ between diabetic and nondiabetic hemodialysis patients. The mechanism of this phenomenon remains elusive. Previously, it was suggested that elevation of AGE levels in uremia might result from the accumulation of unknown AGE precursors. The present study evaluates the in vitro generation of pentosidine, a well identified AGE structure. Plasma samples from healthy subjects and nondiabetic hemodialysis patients were incubated under air for several weeks. Pentosidine levels were determined at intervals by HPLC assay. Pentosidine rose to a much larger extent in uremic than in control plasma. Pentosidine yield, i.e., the change in pentosidine level between 0 and 4 wk divided by 28 d, averaged 0.172 nmol/ml per d in uremic versus 0.072 nmol/ml per d in control plasma (P < 0.01). The difference in pentosidine yield between uremic and control plasma was maintained in samples ultrafiltrated through a filter with a 5000-Da cutoff value and fortified with human serum albumin (0.099 versus 0.064 nmol/ml per d; P < 0.05). Pentosidine yield was higher in pre- than in postdialysis plasma samples (0.223 versus 0.153 nmol/ml per d; P < 0.05). These results suggest that a large fraction of the pentosidine precursors accumulated in uremic plasma have a lower than 5000 Da molecular weight. Addition of aminoguanidine and OPB-9195, which inhibit the Maillard reaction, lowered pentosidine yield in both uremic and control plasma. When ultrafiltrated plasma was exposed to 2,4-dinitrophenylhydrazine, the yield of hydrazones, formed by interaction with carbonyl groups, was markedly higher in uremic than in control plasma. These observations strongly suggest that the pentosidine precursors accumulated in uremic plasma are carbonyl compounds. These precursors are unrelated to glucose or ascorbic acid, whose concentration is either normal or lowered in uremic plasma. They are also unrelated to 3-deoxyglucosone, a glucose-derived dicarbonyl compound whose level is raised in uremic plasma: Its addition to normal plasma fails to increase pentosidine yield. This study reports an elevated level of reactive carbonyl compounds ("carbonyl stress") in uremic plasma. Most have a lower than 5000 Da molecular weight and are thus partly removed by hemodialysis. Their effect on pentosidine generation can be inhibited by aminoguanidine or OPB-9195. Carbonyl stress might contribute to AGE modification of proteins and thus to clinically relevant complications of uremia.

Aged

Plasma levels of pentosidine in diabetic patients: an advanced glycation end product.

Nonenzymatic reactions between glucose and proteins yield advanced glycation end products (AGE) such as pentosidine. AGE accumulate in diabetic patients, alter the structure and function of tissue proteins, stimulate cellular response, and have thus been implicated in diabetic tissue damage. The present study was undertaken to assess the factors determining plasma total pentosidine level in diabetic patients and the possible relation between plasma pentosidine level and diabetic complications. In diabetic patients, including patients with renal failure, plasma pentosidine levels, assessed by HPLC assay, were correlated with serum creatinine (P < 0.0001). In patients with normal renal function, pentosidine levels were correlated with blood glucose control (hemoglobin Alc: P = 0.0028; fructoselysine: P = 0.0133), serum creatinine (P = 0.029), patient age (P = 0.0416), duration of diabetes (P = 0.0431), and total cholesterol (P = 0.0056) and LDL-cholesterol (P = 0.0208). Multiple regression analysis revealed an independent influence of hemoglobin Alc and serum creatinine on pentosidine levels (r2 = 0.216, P = 0.0026). Pentosidine levels were higher in patients with than in those without hypertension (P = 0.043) or ischemic heart diseases (P = 0.0061). No such differences were observed between patients with and without albuminuria or retinopathy. Multiple regression analysis revealed an independent influence of plasma pentosidine on the presence of hypertension (r2 = 0.129, P = 0.0382) and of plasma pentosidine and HDL-cholesterol on the presence of ischemic heart disease (r2 = 0.326, P = 0.0012). The present study demonstrated that plasma pentosidine level was significantly influenced by the quality of glycemic control and renal function. Pentosidine level was also correlated with hypertension and ischemic heart disease, and might be taken as a biomarker of diabetic cardiovascular risk.

Adult

[Prevalence of dementia and its subtypes in a rural area in Japan].

The prevalence of dementia in Japan in 1985 for people aged 65 years or older was 4.8%. Vascular dementia (VD) has been reported to be the commonest subtype A report from Tokyo in 1970 showed that it was 2.8 times more frequent than Alzheimer type dementia (SDAT). We assessed the prevalence of dementia in a rural area (population: 12,931, 25.3% were 65 years or older in 1994) in Kyoko. First, we questioned subjects about their demographic circumstances, memory disturbance, apraxia (agnosia) and daily activities. Our questionnaire was answered by 3.132 (95.8%) subjects, and 2,280 of them agreed to be examined by neurologists. Those who met the appropriate criteria of the DSM-III-R and NINCDS-ADRDA were diagnosed with dementia. By use of the Hachinski ischemic score (HIS), we distinguished VD from non-vascular dementia. In this study patients with non-vascular dementia were diagnosed with SDAT by the neurologists. Analysis of the data revealed that 4.8% of the study population was demented. According to the HIS results, only 3 of 15 had vascular dementia. The prevalence of dementia was the same as the average prevalence in Japan even though the elderly population of this town was twice as high as the average. It is hard to determine the prevalence of dementia in any community. Many factors must be taken into consideration: the coverage rate, the criteria for dementia, and whether to include institutionalized residents. The prevalence of dementia will increase with the aging of the population, and we must collect accurate data in order to plan efficiently.

Aged

[Spinal subarachnoid hemorrhage presenting as disturbance of consciousness with severe hypoglycorrhachia].

We report the case of an 84-year-old woman with spinal subarachnoid hemorrhage who presented with disturbance of consciousness and nuchal stiffness, bloody cerebrospinal fluid and severe hypoglycorrhachia. Initially, it was difficult to determine whether this was a case of spinal subarachnoid hemorrhage, purulent meningitis, or hemorrhagic encephalitis, because of the nuchal stiffness, disturbance of consciousness and severe hypoglycorrhachia. It is known that intracranial subarachnoid hemorrhage is accompanied by mild hypoglycorrhachia, but descriptions of glucose levels in cerebrospinal fluid in cases of spinal subarachnoid hemorrhage are rare. This case suggests that both spinal subarachnoid hemorrhage and intracranial subarachnoid hemorrhage are associated with hypoglycorrhachia. Furthermore, spinal subarachnoid hemorrhage is frequently accompanied by disturbance of consciousness. Therefore, sudden back pain or lumbago might not be interpreted as indicators of spinal subarachnoid hemorrhage, because patients, particularly elderly patients, may lose consciousness. We emphasize that the possibility of spinal subarachnoid hemorrhage should be considered in patients with disturbance of consciousness or hypoglycorrhachia even if they do not complain of sudden back pain.

Aged

Comparison of fluorine-18-FDG PET and thallium-201 SPECT in evaluation of lung cancer.

UNLABELLED: We compared the diagnostic value of [18F]2-fluoro-2-deoxy-D-glucose (FDG) PET imaging and 201Tl SPECT imaging in the detection of primary lung cancer and mediastinal lymph node metastases. METHODS: Thirty-three patients with histologically-proven primary lung cancer were examined with both FDG PET and TI SPECT (early and delayed scans) within a week of each study. For semiquantitative analysis, the tumor-to-nontumor activity ratio (T-to-N ratio) was calculated. RESULTS: Although both techniques delineated focal lesions with an increase in tracer accumulation in 28 patients, PET identified three additional patients in whom Tl SPECT images did not visualize any lesions on both early and delayed scans. In the detection of lung cancer of less than 2 cm in size, FDG PET provided higher sensitivity (six of seven, 85.7%) than did Tl SPECT early scan (one of seven, 14.3%) and delayed scan (four of seven, 57.1%). Neither technique visualized any lesions in two patients who had bronchioloalveolar carcinoma. The T-to-N ratio was significantly higher with FDG PET (10.39 +/- 6.63) than it was with Tl SPECT (early scan, 2.37 +/- 0.86; delayed scan, 3.01 +/- 1.01) (p < 0.0001), whereas there was significant positive correlation between the FDG T-to-N ratio and the thallium T-to-N ratio (p < 0.01). Twenty-two patients had thoracotomies. Regarding the staging of mediastinal nodes, FDG PET detected mediastinal lymph node metastasis that was negative on Tl SPECT, whereas both techniques excluded tumor involvement in enlarged node at CT. CONCLUSION: Both techniques have clinical value for the noninvasive detection of primary lung cancer that is 2 cm or greater in diameter. However, if a PET camera is available, FDG PET is considered the method of choice for the evaluation of patients with suspected primary lung cancer that is less than 2 cm in diameter.

Adenocarcinoma

A case of bowel necrosis due to acute mesenteric ischemia following pulsatile cardiopulmonary bypass.

We report a case of fatal bowel necrosis possibly caused by pulsatile cardiopulmonary bypass (CPB). An 80-year-old female underwent emergency coronary artery bypass grafting (CABG) for unstable angina. Pulsatile CPB was applied because of stenosis of bilateral carotid and renal arteries. On the third postoperative day, total bowel necrosis due to acute mesenteric ischemia was revealed at emergency laparotomy before her death. Pulsatile CPB may increase the risk of distal embolism of dislodged plaque in cases with severe aortic atheromatosis.

Acute Disease

Spontaneous retrograde dissection of the entire thoracic aorta originating in the abdominal aorta. Case report and review of the literature.

Spontaneous retrograde thoracic extension of the abdominal aortic dissection is extremely rare and difficult to manage. Only five cases have been previously reported in the English literature (dissection reaching the ascending aorta in four, dissection limited in the descending thoracic aorta in one), and all the cases of dissection which reached the ascending aorta were lethal. We herein report one case of a 37-year-old man who was operated on for spontaneous retrograde dissection of the entire thoracic aorta originating in the suprarenal abdominal aorta. Preoperative aortogram revealed the site of the intimal tear just above the celiac artery. He urgently underwent graft replacement of the descending thoracic aorta and the abdominal aorta with reimplantation of the thoracoabdominal visceral arteries. Although the patient had to undergo the second operation for the dissection of the remaining thoracic aorta four months postoperatively, he has been doing well 18 months after the second operation.

Adult

[Clinical study on the inhibitory effect of a 5-HT3 antagonist, granisetron, for nausea and vomiting induced by chemotherapy (CHOP, VEPA, high-dose ETP) for non-Hodgkin's lymphoma].

The antiemetic effect of granisetron on nausea and vomiting induced by cancer chemotherapy (CHOP, VEPA, VEPA-B, massive dose of ETP) was studied in fifty patients with non-Hodgkin's lymphoma. There was almost no difference in the inhibitory effect by regimen, with the rates of perfect inhibition of nausea and vomiting standing at 55.6% to 60%. Nausea and vomiting was perfectly controlled in 60% of 35 patients receiving CHOP therapy. As a part of this study, a comparison was made of perfect inhibitory effect on nausea and vomiting by potency of chemotherapy under the potency scale of 750 mg/m2 of CPA as 1, revealing no significant difference in the rates of complete inhibition as 71.4% for a drug potency of less than 0.8 vs 52.4% for 0.8 or above (p = 0.26). However, it was clear that the higher the dose of chemotherapy, the lower the rate of complete inhibition. The results confirmed the high efficacy and safety of granisetron in the treatment of nausea and vomiting induced by cancer chemotherapy.

Adult

[Perforation of the bladder by a peritoneal catheter: an unusual late complication of ventriculo-peritoneal shunt].

Late perforation of the bladder by an abdominal catheter of a ventriculoperitoneal (VP) shunt is extremely rare. We report the successful treatment of a patient who presented with this complication. An 82-year-old woman received a V-P shunt for normal pressure hydrocephalus following subarachnoid hemorrhage. Ten years later she was admitted to our hospital with neck pain. A few days after admission, the tip of the peritoneal catheter was found to be protruding from the urethra during urination. Subsequently, the patient developed meningitis. Contrast study of the distal tubing demonstrated the continuity of the peritoneal shunt tube. After the entire system was removed, antibiotic treatment was administered for 2 weeks. and a new VP shunt was placed on the opposite side. The post-operative course was uneventful. Previous reports regarding complications after the placement of a VP-shunt show that periodic chest and abdominal X-ray studies are important. In this case, however, the peritoneal tube was not able to be observed on abdominal plain film. For this reason, an unfaded radiopaque tube is necessary if there is to be early diagnosis of late organic perforation by a peritoneal shunt tube.

Aged

Fluorine-18-FDG PET imaging is negative in bronchioloalveolar lung carcinoma.

UNLABELLED: The goals of our study were to establish PET accuracy with 18F-fluorodeoxyglucose (FDG) in finding localized formations of bronchioloalveolar lung carcinoma (BAC) and to investigate the correlation between FDG uptake and the degree of cell differentiation in adenocarcinoma of the lung. MATERIALS: Twenty-nine patients with 30 adenocarcinomas of the lung (7 bronchioloalveolar lung carcinomas, 9 well differentiated, 2 well-moderately differentiated, 11 moderately differentiated and 1 poorly differentiated) were studied. All patients underwent thoracotomies within 4 wk after the FDG PET study. For qualitative analysis, the degree of FDG activity in the tumors was visually scored using a five-point grading system: 0 = same to background activity, 1 = less than mediastinal blood-pool activity, 2 = same to mediastinal blood-pool activity, 3 = slightly greater than mediastinal blood-pool activity and 4 = substantially greater than mediastinal blood-pool activity. Foci of activity with Grades 2-4 were considered tumors. For semiquantitative analysis, standardized uptake values (SUV) were calculated. RESULTS: In 7 BACs, 4 lesions (57%) showed negative results on FDG PET, while in 23 non-BACs, only 1 lesion (4%), which was a well-differentiated adenocarcinoma showed a negative result. BACs' mean visual score (1.43 +/- 1.27) was significantly lower than that of non-BACs (3.17 +/- 1.03) (p = 0.001). The BACs' mean SUV (1.36 +/- 0.821) was significantly lower than that of well-differentiated adenocarcinomas (2.92 +/- 1.28) (p = 0.014); the mean SUV of well-differentiated adenocarcinomas was significantly lower than that of moderately differentiated adenocarcinomas (4.63 +/- 1.86) (p = 0.031). No significant differences were apparent in average size among these three histologic types. CONCLUSION: A correlation was observed between FDG uptake and the degree of cell differentiation in adenocarcinoma of the lung. FDG PET may show negative results for BAC.

Adenocarcinoma

[A pharmacokinetic study of the value of oral cytarabine ocfosfate in the treatment of hematological malignancies].

Cytarabune ocfosfate (SPAC) is rapidly transformed into cytarabine (ara-C) when orally administered. The pharmacokinetics of SPAC was studied in six patients with acute non-lymphocytic leukemia (ANLL) and/or myelodysplastic syndromes (MDS) after oral administration of SPAC at 100 to 400 mg/day for 14 days. Plasma ara-C concentrations reached a plateau in 48 to 96 hours after initiation of SPAC administration, remained at this or a little higher level until one day after its termination and were less than 1 ng/ml 8 days after the termination. From all of pharmacokinetic data, the oral administration of SPAC at 150 to 300 mg/m2/day was pharmacokinetically concluded to be comparable to the continuous infusion of ara-C at 20 mg/m2/day. All of the patients could receive SPAC for 14 days. SPAC is considered to be useful for consolidation or maintenance chemotherapy of ANLL or MDS outpatients who are unable to undergo intensive chemotherapy.

Administration, Oral

Coronary artery bypass grafting for an adult with coronary disease due to Kawasaki disease.

Surgical treatment for patients over the age of forty with coronary aneurysms associated with Kawasaki disease is rare. We report on a 47-year-old man who underwent coronary artery bypass grafting using the left internal thoracic arteries (ITA) and right gastroepiploic (GEA). The postoperative course was uneventful. One month later, the normal stress thallium-201 myocardial perfusion imaging was normal and coronary angiography showed good patency for the ITA, GEA, and saphenous vein grafts. He had some coronary risk factors including smoking, hypertension and hyperlipidemia. Histological examination of a sample shows that the coronary artery sequelae of Kawasaki disease have already become part of increasing burden of adult ischemic heart disease.

Coronary Angiography

Assessment of P-glycoprotein in patients with malignant bone and soft-tissue tumors using technetium-99m-MIBI scintigraphy.

UNLABELLED: Overexpression of P-glycoprotein (Pgp) has been detected in many malignant tumors including bone and soft-tissue tumors. Technetium-99m-MIBI has proved to be a transport substrate for Pgp. The purpose of our study was to explore 99mTc-MIBI as a functional imaging agent reflecting Pgp expression in malignant bone and soft-tissue tumors. METHODS: Technetium-99m-MIBI scintigraphy was performed in 30 patients with malignant bone and soft-tissue tumors. Radionuclide angiography with 99mTc-MIBI was done and, at 15 min and 3 hr postinjection of the radiopharmaceutical, imaging was performed. The 99mTc-MIBI uptake ratio was calculated by dividing the lesion count by the background count. The washout rate (WR) for 99mTc-MIBI was calculated by the following formula: WR = 100 x [(Te-Be)-(Td-Bd)]/(Te-Be) (%), where Te and Td = decay-corrected count density of the tumor in the 15-min and 3-hr images, respectively. Be and Bd = decay-corrected count density of the background in the 15-min and 3-hr images, respectively. The lesions were resected by open biopsy to obtain a histopathological diagnosis, and immunohistochemical staining was performed to detect Pgp. RESULTS: Twenty-four of 30 patients showed significant uptake at the 15-min image. In these 24 patients, the lesions with a high Pgp expression showed a similar 99mTc-MIBI perfusion index (3.00 +/- 1.04) and uptake ratio (2.05 +/- 0.58) at the 15-min image to those of lesions without a high Pgp expression (2.65 +/- 0.85 and 2.28 +/- 0.64, respectively). On delayed images, the 99mTc-MIBI uptake ratio was lower in patients with a high Pgp expression than in patients without a high Pgp expression (1.37 +/- 0.41 versus 1.87 +/- 0.39, p < 0.01). The washout ratio of 99mTc-MIBI was higher in patients with a high Pgp expression than in patients without a high Pgp expression (66% +/- 25% versus 29% +/- 18%, p < 0.001). None of the 6 patients without 99mTc-MIBI uptake at the 15-min imaging showed 201TI uptake, and only 2 had a high Pgp expression. CONCLUSION: In malignant bone and soft-tissue tumors, perfusion and initial 99mTc-MIBI uptake were not related to the Pgp expression; however, washout of 99mTc-MIBI from the tumor was related to Pgp expression. Technetium-99m-MIBI scintigraphy with washout analysis may be a useful method for the evaluation of Pgp overexpression and its function.

ATP Binding Cassette Transporter, Subfamily B, Mem