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H Ochi

Publications and source records attributed to H Ochi.

At least 91 records · Page 5Linked to original sources
PubMed1999

Lipid A directly inhibits IL-4 production by murine Th2 cells but does not inhibit IFN-gamma production by Th1 cells.

Lipopolysaccharide (LPS) is known to be an immunopotentiator but its effect on cytokine production by Th1 and Th2 cells is unknown. We found that high amounts of LPS, its lipid A moiety, and a lipid A analog all induced a decrease in IL-4 production and an increase in IFN-gamma production when given to keyhole limpet hemocyanin (KLH)-restimulated lymph node cells prepared from KLH-primed mice. Lipid A was similarly found to inhibit IL-4 production by purified CD4+ T cells and Th2 clones activated with immobilized anti-CD3epsilon and anti-CD28 antibodies, suggesting that the inhibition is not indirectly mediated through effects on antigen-presenting cells. No inhibitory effect of lipid A was observed on IFN-gamma production by a Th1 clone. Production of both IL-4 by the Th2 clones and IFN-gamma by the Th1 clone were inhibited by the immunosuppressive agent cyclosporin A. These findings indicate that lipid A can directly inhibit IL-4 production by CD4+ T cells without inhibiting the production of IFN-gamma. Lipid A may therefore become a useful tool to study the intracellular events that differentiate Th1 and Th2 cells.

Animals↗
PubMed1999

Clinical need for both scintigraphy with technetium-99m GSA and per-rectal portal scintigraphy in some patients with chronic liver disease.

Scintigraphy with 99mTc-diethylenetriaminepentaacetate with galactosyl human serum albumin (99mTc-GSA) and per-rectal portal scintigraphy are useful for evaluating hepatic functional reserve and portal circulation, respectively. We did the procedures simultaneously in some patients to examine the relationship between hepatic functional reserve and portal circulation in chronic liver disease. Scintigraphy with 99mTc-GSA was done in 10 healthy subjects, 45 patients with chronic hepatitis, and 165 patients with cirrhosis. Fifty-seven patients (13 with hepatitis and 44 with cirrhosis) also underwent per-rectal portal scintigraphy with 99mTc-pertechnetate within two weeks. A receptor index was calculated by dividing the radioactivity of the liver region of interest (ROI) by that of the liver-plus-heart ROI at 15 min after the injection of 99mTc-GSA. The index of blood clearance was calculated by dividing the radioactivity of the heart ROI at 15 min by that of the heart ROI at 3 min. A solution containing 99mTc-pertechnetate was instilled into the rectum, and serial scintigrams were taken while radioactivity curves for the liver and heart were recorded sequentially. A per-rectal portal shunt index was determined by calculating the ratio of counts for the liver to counts for the heart integrated for 24 seconds immediately after the appearance of the liver time-activity curve. The median receptor index was lower for more severe liver disorders, increasing in the order of chronic hepatitis, compensated cirrhosis and decompensated cirrhosis, and the median index of blood clearance was higher. The median receptor index was significantly lower when a complication (varices, ascites, or encephalopathy) was present, and the median index of blood clearance was higher. The shunt index was correlated significantly with the two other indices, but these values for some one-third of the patients disagreed in either indices. Scintigraphy with 99mTc-GSA and per-rectal portal scintigraphy with 99mTc-pertechnetate are both needed for accurate assessment of the severity of chronic liver disease before treatment-making decisions, because in some patients, results are not correlated.

Administration, Rectal↗
PubMed1999

Thallium and FDG uptake by atelectasis with bronchogenic carcinoma.

We report a case of bronchogenic carcinoma with atelectasis studied by T1-SPECT and FDG-PET. In the carcinoma, abnormally high uptake of T1 and FDG were detected, but in the region of atelectasis, an abnormally high uptake of T1 with a relatively low uptake of FDG were observed. On quantitative analyses, the T1 retention indexes of the tumor and atelectasis were 29.7 and 42.0. The mean SUVs of FDG of the tumor and the atelectasis were 8.92 and 1.28. T1-SPECT could not distinguish the atelectasis from the carcinoma. FDG-PET was superior to T1-SPECT in this case in detecting malignancy and distinguishing it from atelectasis.

Biological Transport↗
PubMed1999

Two cases of chronic tonsillitis studied by FDG-PET.

We report two cases of chronic tonsillitis studied by FDG-PET. Symmetrical high FDG uptake by the tonsils was observed in both cases. On histopathologic examination of the resected tonsils, follicular hyperplasia was observed with proliferation of lymphocytes in the germinal centers. Increased glucose metabolism in active inflammation involving lymphocyte proliferation was thought to be a cause of high FDG uptake by tonsils in chronic tonsillitis.

Adolescent↗
PubMed1999

Two cases of focal nodular hyperplasia of the liver: value of scintigraphy with Tc-99m GSA and positron emission tomography with FDG.

Focal nodular hyperplasia (FNH) of the liver is relatively rare, and can be difficult to differentiate from other benign tumors arising in the liver. We describe a 23-year-old woman and a 25-year-old man with FNH. They were hospitalized for further evaluation of a space-occupying lesion in the liver. Scintigraphy with Tc-99m diethylenetriaminepentaacetic acid galactosyl human serum albumin (Tc-99m GSA) revealed increased radioactivity in the tumor in one patient and radioactivity similar to that in the normal part of liver in the other. F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) showed uptake similar to that of the normal liver in both patients. FNH was diagnosed on the basis of angiographic findings and histological findings in liver biopsy specimens. Our results show that scintigraphy with Tc-99m GSA and FDG-PET may provide information helpful in the diagnosis of FNH.

Adult↗
PubMed1999

Calcitriol for bone loss in patients with primary biliary cirrhosis.

Because osteoporosis is a common complication of primary biliary cirrhosis, we evaluated the effects of calcitriol (1alpha, 25-dihydroxyvitamin D3) on bone mineral density in 34 women with primary biliary cirrhosis (stage I disease in 16 patients, stage II in 9, stage III in 4, and stage IV in 5). Patients were assigned randomly to receive calcitriol (0.5mg twice a day) or not. Bone mineral density of the lumbar vertebrae was measured by dual-energy X-ray absorptiometry at least twice during a period of 12-43 months. The mean annual change in bone mineral density was 0.1% in the treatment group and -3.1% in the control group. The median annual change (with 25th and 75th percentiles) in bone mineral density was 0.3% (-0.5%, 1.9%) in the treated group and -3.1% (-4.1%, -2.1%) in the control group. This difference between the two groups was significant (P = 0.0007, Mann-Whitney U-test). Our findings suggest that calcitriol prevents bone loss and may be an effective treatment for osteoporosis in patients with primary biliary cirrhosis.

Absorptiometry, Photon↗
PubMed1999

Regulation of B-1 cell activation and its autoantibody production by Lyn kinase-regulated signallings.

The src-family protein tyrosine kinase, Lyn, has been reported to play a crucial role in the regulation of B-cell antigen receptor (BCR)-mediated signalling. To elucidate the role of Lyn in the maintenance of immunological tolerance and the prevention of B-1 cell activation and its autoantibody production, Lyn-deficient mice were crossed with transgenic mice carrying the immunoglobulin heavy and light chain genes encoding an autoantibody against mouse red blood cells. In the transgenic mice, most peripheral B cells expressed the B-1 cell phenotype. When the transgenic mice were bred in specific pathogen-free (SPF) conditions, B-1 cells were anergic and did not produce any autoantibody. In contrast, Lyn-deficient transgenic mice kept in the same SPF conditions revealed markedly increased numbers of activated B-1 cells and developed severe autoimmune haemolytic anaemia. Moreover, the mice had a huge splenomegaly containing a remarkable accumulation of erythroblasts, resulted from extramedullary erythropoiesis, in addition to the increased numbers of lymphoblast-like cells of the B-1 cell lineages. The present study demonstrates a crucial role of Lyn kinase in the regulation of B-1 cell activation and maintenance of tolerance.

Anemia, Hemolytic, Autoimmune↗
PubMed1999

Calcitriol for bone disease in patients with cirrhosis of the liver.

BACKGROUND: Osteoporosis is associated with cirrhosis of the liver, but the effects of therapy for osteoporosis associated with cirrhosis are still controversial. METHODS: We evaluated the effects of calcitriol (1alpha,25-dihydroxyvitamin D3) on bone mineral density (BMD) in 76 patients (26 men and 50 women) with cirrhosis who were assigned randomly to receive calcitriol (0.5 mg twice per day) or not. The BMD of the lumbar vertebrae was measured by dual-energy X-ray absorptiometry at least twice, 12-57 months apart. RESULTS: For men, the mean annual change in BMD was 1.1% in the treated group and -0.4% in the control group. The median (25th and 75th percentiles) annual change in BMD was 0.6 (-0.1, 2.1%) in the treated group and -1.4 (-1.9, 1.6%) in the control group. The difference in the median annual change between the two groups was significant (P = 0.013). For women, the mean annual change in BMD was -0.5% in the treated group and -2.3% in the control group. The median (25th and 75th percentiles) annual change in BMD was -0.5 (-1.8, 1.3%) in the treated group and -1.5 (-3.8, -0.7%) in the control group. This difference was significant (P = 0.011). CONCLUSIONS: Our results suggest that calcitriol can prevent bone loss and, therefore, may be useful for the treatment of bone disease in patients with cirrhosis of the liver.

Absorptiometry, Photon↗
PubMed1999

Use of scintigraphy with 99mtechnetium galactosyl human serum albumin for staging of primary biliary cirrhosis and assessment of prognosis.

BACKGROUND: Conventional models for prediction of survival in patients with primary biliary cirrhosis (PBC) are based on the results of blood tests and on the clinical condition, which may be affected by treatment. We evaluated the usefulness of hepatic receptor imaging with [99mtechnetium]-diethylenetriaminepentaacetic acid galactosyl human serum albumin (GSA) for the staging and prognosis of PBC without the need for reference to laboratory test results. METHODS: The subjects were 45 patients with PBC, 10 healthy subjects, 62 patients with chronic hepatitis and 144 patients with cirrhosis. Computer acquisition of gamma-camera data was started just before the injection of 185 MBq [99mTc]-GSA and was stopped 20 min later. Time-activity curves were generated from regions of interest (ROI) for the heart and liver. A receptor index was calculated by dividing the radioactivity of the liver ROI by that of the liver-plus-heart ROI 15 min after the injection. An index of blood clearance was calculated by dividing the radioactivity of the heart ROI 15 min after the injection by that of the heart ROI 3 min after the injection. RESULTS: The median receptor index was higher in patients with PBC than in those with cirrhosis. Among patients with PBC, the receptor index was lower in those with stage IV disease than in those in stages I, II or III. The index of blood clearance was lower in patients with PBC than in those with cirrhosis. Among patients with PBC, the index of blood clearance was higher in those with stage IV disease than in those in stages I, II or III. The receptor index was correlated significantly both to the risk score of the Mayo model and to the prognostic index of the Japanese model. The index of blood clearance was also correlated significantly to this score and prognostic index. CONCLUSIONS: Hepatic receptor imaging with [99mTc]-GSA is useful for the evaluation of hepatic functional reserve, staging of PBC and assessment of prognosis.

Asialoglycoprotein Receptor↗
PubMed1999

Leukocyte function-associated antigen-1 expression on decidual natural killer cells in patients with early pregnancy loss.

A large number of CD56(bright) natural killer (NK) cells, which comprise a very small fraction of peripheral blood lymphocytes, appear in the endometrium during the late secretory phase and early pregnancy. These cells are thought to immunologically maintain or inhibit pregnancy. However, the details regarding their contribution to the immuno-elimination systems of embryonic cells or decidual stromal cells remain unclear. Recently, leukocyte function-associated antigen-1 (LFA-1) was shown to play a critical role in the regulation of NK cytolysis in peripheral blood lymphocytes. We speculated that LFA-1 on the decidual CD56(bright) NK may be involved in the regulation of pregnancy. The expression of LFA-1 on the decidual CD56(bright) NK cells was analysed using flow cytometry with fluorescent monoclonal antibodies; CD56 (NKH1), CD16 (Fcg-R3) and CD11a (LFA-1 alpha-chain). In comparison with non-pregnant endometrium during the late secretory phase, the subpopulation of CD56(bright)CD16(-) cells in decidual lymphocytes was significantly increased during normal pregnancy, but was less than that in early pregnancy loss (P < 0.05). Furthermore, the number of CD56(bright) NK cells expressing LFA-1 was significantly higher in early pregnancy loss, and the late secretory phase, than during normal pregnancy (P < 0.05). Our results indicate that up-regulation of LFA-1 on CD56(bright) NK cells is related to spontaneous abortion or the onset of menstruation.

Abortion, Spontaneous↗
PubMed1999

Preoperative clinical radioimmunodetection of pancreatic cancer by 111 In-labeled chimeric monoclonal antibody Nd2.

The present study was carried out with the purpose of evaluating the clinical usefulness of radioimmunodetection (RAID) with 111In-labeled murine/human chimeric monoclonal antibody, Nd2 (c-Nd2) in patients with pancreatic cancer. Nineteen patients suspected to have pancreatic cancer were administered intravenously 74 MBq/2 mg 111In-labeled c-Nd2 in 100 ml of saline containing 2% albumin over 30 min. A scintigram was obtained on the 3rd day after infusion by using single photon emission computed tomography (SPECT) imaging. Of the 14 patients finally diagnosed as having pancreatic cancer on the basis of surgical specimens or progress of disease, specific focal uptake at the site of the tumor was detected in 12 (true positive cases), representing a sensitivity of 85.7% (12/14), and liver metastasis was found in one case with metastasis. Of the 5 patients diagnosed with tumor-forming pancreatitis (TFP), 4 patients demonstrated true negative imaging, but one patient whose tumor demonstrated interesting findings in histology and immunostaining, showed false positive imaging. Of patients investigated for human anti-chimeric antibody (HACA) response, none showed HACA response, and no allergic reaction was seen in any of the patients administered c-Nd2. These results suggest that RAID with 11In-labeled c-Nd2 is useful for differential preoperative diagnosis between invasive pancreatic cancer and TFP.

Aged↗
PubMed1999

Exercise four hour redistribution thallium-201 single photon emission computed tomography and exercise induced ST segment elevation in detecting the viable myocardium in patients with acute myocardial infarction.

OBJECTIVE: To investigate the specificity and sensitivity of the combination of redistribution in exercise thallium-201 single photon emission computed tomography (SPECT) and exercise induced ST elevation for detecting the viable myocardium in patients with acute myocardial infarction. DESIGN: 37 patients were studied within seven weeks of onset of Q wave myocardial infarction (anterior in 22, inferior in 15). All patients underwent exercise four hour redistribution thallium-201 SPECT and positron emission tomography using fluorine-18-fluorodeoxyglucose (FDG) and nitrogen-13 ammonia under fasting conditions. RESULTS: Sixteen patients showed exercise induced ST elevation >/= 1.5 mm, and 15 of these had increased FDG uptake in the infarct region. Eleven of 16 patients (10 of 11 patients with anterior infarctions) with irreversible thallium-201 defects and increased FDG uptake showed exercise induced ST elevation. The sensitivity, specificity, and predictive accuracy of redistribution, exercise induced ST segment elevation, or both for detecting increased FDG uptake were 82%, 75%, and 67% (94%, 75%, and 91% for anterior infarctions), respectively. CONCLUSIONS: In patients with acute Q wave myocardial infarction, the combination of redistribution in exercise thallium-201 SPECT and exercise induced ST elevation can detect the viable myocardium in the infarct region with high sensitivity and specificity, especially in patients with anterior infarctions.

Adult↗
PubMed1999

The influence of the maternal heart rate on the uterine artery pulsatility index in the pregnant ewe.

We investigated the influence of the maternal heart rate on the uterine artery pulsatility index in pregnant ewes. We used an external pacemaker to alter the heart rate of 5 pregnant ewes at 16-17 weeks of pregnancy and examined the effect of changes in the maternal heart rate on the uterine artery flow velocity waveforms and the pulsatility index, as determined by Doppler velocimetry. The uterine artery pulsatility index showed a significant negative correlation with the maternal heart rate. There were no significant changes in other hemodynamic parameters. The maternal heart rate had a significant influence on the uterine artery pulsatility index.

Animals↗
PubMed1999

Fetal compromise assessed by Doppler ultrasound of venous flow in pregnancy-induced hypertension.

The purpose of this study was to determine the change of venous flow patterns in the inferior vena cava of fetuses in pregnancy-induced hypertension (PIH). We studied 80 normal pregnant women and 46 pregnant women with PIH and their fetuses. We determined the pulsatility index (PI) for arterial vessels, the ratio of peak flow velocities in early diastole and late diastole (E/A) in atrioventricular valves, and the preload index for the inferior vena cava. Twelve of the 46 PIH women showed an umbilical artery PI higher than the 95th percentile in normal pregnant women. Five of them demonstrated a decreased middle cerebral artery PI. Three of the 5 had an increased mitral E/A. Two of them had a decreased tricuspid E/A, an increased preload index, and a poor prognosis. An increased preload index suggests severe compromise in fetuses with a redistribution of arterial and intracardiac blood flow.

Adult↗
PubMed1999

Sulfonylureas stimulate renin secretion from the perfused kidney of the rat.

To elucidate whether sulfonylureas directly influence renin secretion, the effect of tolbutamide, glibenclamide, or chlorpropamide on renin secretion was investigated by using the perfused kidney of the rat. The isolated kidneys of male Wistar rats (200-250 g) were perfused with a medium containing 2 microM tolbutamide, 2 microM glibenclamide, and 2 microM chlorpropamide, respectively. Renin activity significantly increased from a basal value of 11.7 +/- 3.6 to a peak value of 20.6 +/- 5.5 ng/Ang I/ml/h with tolbutamide, from 14.4 +/- 4.6 to 32.7 +/- 6.5 ng/Ang I/ml/h with glibenclamide, and from 15.0 +/- 4.9 to 30.4 +/- 6.1 ng/Ang I/ml/h with chlorpropamide. The cAMP concentration in the effluent was not changed by the addition of the sulfonylureas. In kidneys perfused with a calcium-free medium, glibenclamide produced a significant increase in renin activity from a basal value of 13.4 +/- 2.1 to a peak value of 30.6 +/- 3.4 ng Ang I/ml/h. These results suggest that sulfonylureas stimulate renin secretion from perfused rat kidneys.

Animals↗
PubMed1999

Intranuclear distribution of 8-hydroxy-2'-deoxyguanosine. An immunocytochemical study.

We used immunofluorescence staining (monoclonal antibody N45.1) with cytological imprinting to study changes in the intranuclear distribution of 8-hydroxy-2'-deoxyguanosine in renal cells of male Wistar rats after oxidative stress by ferric nitrilotriacetate. In the control proximal tubule cells, small spherical signals were uniformly distributed throughout the nuclei. Under oxidative stress, immunofluorescence intensity was increased, especially near nuclear membrane. In cells with nuclear shrinkage or deformity, intense, diffuse signals throughout the nuclei were observed. Our results suggest that specific nuclear sites are vulnerable to oxidative DNA damage and that diffuse intense signals precede cell death after oxidative stress.

8-Hydroxy-2'-Deoxyguanosine↗