Biomedical subjects

K Sueyoshi

Publications and source records attributed to K Sueyoshi.

At least 19 recordsLinked to original sources

PubMed2004

Mucin expression in pleomorphic adenoma of salivary gland: a potential role for MUC1 as a marker to predict recurrence.

BACKGROUND: Pleomorphic adenoma of the salivary gland (PA) is essentially a benign neoplasm. However, patients with recurrent PA are difficult to manage. There are rare reports on useful immunohistochemical markers to detect a high risk of recurrence when the primary lesions are resected. AIMS: To find a new marker to predict the recurrence of PA. METHODS: Primary lesions of PA were collected from nine patients showing subsequent recurrence and from 40 patients without recurrence during at least 10 years of follow up of the disease. Paraffin wax embedded tumour samples of the two groups were examined for the expression profiles of MUC1 (differentially glycosylated forms), MUC2, MUC4, MUC5AC, and MUC6 using immunohistochemistry. Several clinicopathological factors were also examined. RESULTS: In univariate analysis of the factors examined, MUC1/DF3 high expression (more than 30% of the neoplastic cells stained) in the primary lesions was seen more frequently in patients with recurrence (four of nine) than in those without recurrence (three of 40; p = 0.011). Larger tumour size (more than 3.0 cm) of the primary PA was also a significant (p = 0.035) risk factor for the recurrence of PA. In multivariate analysis, only high expression of MUC1/DF3 was found to be a significant independent risk factor for the recurrence of PA (p = 0.021). CONCLUSIONS: Expression of MUC1/DF3 in PA is a useful marker to predict its recurrence. Those patients with PA showing positive MUC1/DF3 expression should be followed up carefully.

Adenoma, Pleomorphic↗

PubMed2003

Overexpression of cyclooxygenase-2 in high-grade human transitional cell carcinoma of the upper urinary tract.

OBJECTIVE: To examine cyclooxygenase (COX)-2 expression (a key enzyme in the synthesis of prostaglandins, and involved in carcinogenesis of human epithelial tumours) in human transitional cell carcinomas (TCCs) of the renal pelvis and ureter, and to determine whether COX-2 expression correlates with the clinicopathological characteristics of the disease. MATERIALS AND METHODS: Specimens from 144 patients with TCC of the upper urinary tract who had undergone nephroureterectomy were analysed immunohistochemically, and 23 were also analysed by immunoblotting. RESULTS: Immunoblot analysis showed COX-2 immunoreactivity in 17 (74%) of 23 tumours, but not in normal transitional epithelium. COX-2 was localized to the cytoplasm of cancer cells and expressed in 108 (75%) of 144 tumours, as assessed by immunohistochemical analysis. COX-2 expression correlated with tumour grade (P < 0.008), being detected in one of nine grade 1, 77 (79%) of 97 grade 2 and 30 (79%) of 38 grade 3 tumours. Other variables including tumour stage were not associated with COX-2 expression. CONCLUSIONS: We show for the first time that COX-2 is frequently expressed in TCC of the upper urinary tract and is associated with the degree of tumour cell differentiation, indicating that COX-2 may be involved in TCC carcinogenesis at an early and/or late stage, and could be a useful target for chemoprevention of this type of cancer.

Aged↗

PubMed2001

Usefulness of tc-99m MIBI SPECT in predicting multidrug resistance gene expression levels in non-small cell lung cancer--a preliminary report.

In this study we investigated whether Tc-99m hexakis 2-methoxy isobutyl isonitnile (Tc-99m MIBI) single-photon emission computed tomography (SPECT) has a correlation with the multidrug resistance (MDRI) and multidrug resistance-associated protein (MRP1) gene expression levels in non-small cell lung cancer (NSCLC). Fifteen patients with NSCLC were studied. SPECT images were obtained 15 (early) and 120 (delayed) min after injection of Tc-99m MIBI. We chose only one transverse section and set the region of interest over the tumor and out of the body. The mean counts in the tumor on early and delayed images were corrected by using those in the background and represented as Te and Td, respectively. Resected tumor specimens were frozen with liquid nitrogen and each positive control cell line was cultured. After the total ribonucleic acid (RNA) was extracted from specimens and cell lines, the complimentary deoxyribonucleic acid (cDNA) was amplified by the reverse transcription-polymerase chain reaction (RT-PCR) method. Each product was electrophoresed and fluorointensity was measured. The gene expression level was represented as the ratio of that of the positive control cell line. Te and Td indicated a significant correlation with the MDR1 gene expression level (p = 0.015 and p = 0.022), but not the gene of MRP1 (p = 0.100 and p = 0.145). In conclusion, Te and Td are useful parameters in predicting the MDRI gene expression level, but not MRPI in NSCLC.

Aged↗

PubMed2001

A serine endopeptidase from cucumber leaves is inhibited by L-arginine, guanidino compounds and divalent cations.

An endopeptidase was purified and characterized from green leaves of cucumber (Cucumis sativus L. suyo). The purified enzyme, a basic amino acid-specific endopeptidase with a pI of 5.0, was a monomeric protein of 80 kDa whose pH optimum was 9.5. Inhibitor analysis suggested that it was a serine endopeptidase and contained sulfhydryl groups essential for catalytic activity. Analysis of internal amino acid sequences of the endopeptidase showed no significant similarity to other proteins. Its activity was inhibited by L-Arg and guanidino compounds having high hydrophobicity, as well as divalent cations such as Mg2+ and Ca2+. The K(i) values of L-Arg and Mg2+, which are also likely in vivo inhibitors, were 3.5 and 10 mM, respectively. Inhibition by L-Arg and Mg2+ was additive, and more than 70% of the activity was reversibly inhibited under their physiologically significant concentrations. These results suggest that the enzyme is possibly regulated by L-Arg and/or guanidino compounds, and by divalent cations in vivo.

Agmatine↗

PubMed2001

A high molecular weight glutamyl endopeptidase and its endogenous inhibitors from cucumber leaves.

We purified a glutamyl endopeptidase that is a major foliar endopeptidase in cucumber. The endopeptidase had a molecular mass of 400 kDa, consisted of four subunits of 97 kDa, and was inactivated by SH-modifying reagents. Its optimum pH and optimum temperature were 8.0 and 30-37 degrees C, respectively. An internal amino acid sequence of the endopeptidase was highly homologous to a partial sequence of unidentified proteins deduced from genetic information for Arabidopsis thaliana, soybean and rice, but not to the sequences of bacterial glutamyl endopeptidases or animal proteases. Therefore, the unidentified proteins might be glutamyl endopeptidases and be widely distributed only among plant species. The activity of the cucumber glutamyl endopeptidase was inhibited by at least three inhibitors existing in cucumber leaves. One of the inhibitors was a competitive inhibitor of 25 kDa, which did not significantly inhibit commercial endopeptidases derived from animals and microorganisms. This suggests that the cucumber glutamyl endopeptidase might be controlled by endogenous inhibitors in vivo.

Amino Acid Sequence↗

PubMed2001

Utility of Tc-99m GSA whole-body scintigraphy in detecting bone metastases from hepatocellular carcinoma.

Recent advances in the treatment of hepatocellular carcinoma (HCC) have prolonged patient survival. However, the number of patients with bone metastases identified during follow-up examinations has increased. Tc-99m Sn-N-pyridoxy-5-methyltryptophan (Tc-99m PMT) has been reported to accumulate at a high rate in HCC lesions and bone metastases. In the patient described here, whole-body scintigraphy showed accumulation of DTPA galactosyl human serum albumin (Tc-99m GSA) and Tc-99m PMT in bone metastases from HCC. The authors suggest that asialoglycoprotein receptors may be present in bone metastases from well-differentiated HCC. Tc-99m GSA whole-body imaging can be used to detect bone metastases from HCC and to evaluate hepatic reserve.

Albumins↗

PubMed2001

Rapid N transport to pods and seeds in N-deficient soybean plants.

Non-nodulated soybean (Glycine max (L.) Merr.) plants were cultivated hydroponically under N-sufficient (5 mM NaNO(3)) or N-deficient (0.5 mM NaNO(3)) conditions. (13)N- or (15)N- labelled nitrate was fed to the cut end of the stems, and the accumulation of nitrate-derived N in the pods, nodes and stems was compared. Real-time images of (13)N distribution in stems, petioles and pods were obtained using a Positron Emitting Tracer Imaging System for a period of 40 min. The results indicated that the radioactivity in the pods of N-deficient plants was about 10 times higher than that of N-sufficient plants, although radioactivity in the stems and nodes of N-deficient versus N-sufficient plants was not different. A similar result was obtained by supplying (15)NO(3) to cut soybean shoots for 1 h. The fact that the N translocation into the pods from NO(3) fed to the stem base was much faster in N-deficient plants may be due to the strong sink activity of the pods in N-deficient plants. Alternatively, the redistribution of N from the leaves to the pods via the phloem may be accelerated in N-deficient plants. The temporal accumulation of (13)NO(3) in nodes was suggested in both N-sufficient and N-deficient plants. In one (13)NO(3) pulse-chase experiment, radioactivity in the stem declined rapidly after transferring the shoot from the (13)NO(3) solution to non-labelled NO(3); in contrast, the radioactivity in the node declined minimally during the same time period.

Amino Acids↗

PubMed2001

[Three-dimensional CT angiography of the hepatic artery with multislice CT: differences in image quality according to scanning pitch].

Three-dimensional CT angiography was reconstructed from the hepatic artery using multislice CT, and the effect of pitch during scanning on the quality of obtained images was examined. We randomly divided patients into two groups, with images of one group scanned at helical pitch 3 and images of the other at helical pitch 5.5. CT angiography was reconstructed by a volume-rendering technique. Evaluation was done visually, taking the sharpness of images of branches of the hepatic artery as a measure. Three-dimensional imaging scanned at pitch 3 tended to be better than that scanned at pitch 5.5.

Adult↗

PubMed2000

Serial changes in N-isopropyl-p[125I]-iodoamphetamine in mouse lung observed with a confocal laser scanning microscope.

Serial changes in N-isopropyl-p[125I]-iodoamphetamine (125I-IMP) in mouse lungs were observed with a confocal laser scanning microscope. Male mice were intravenously injected with 125I-IMP and subjected to autoradiographic procedures 20 minutes, and 3 and 24 hours after injection. Differential interference contrast (DIC) images and confocal images were obtained with a confocal laser scanning microscope, and superimposed images were evaluated. Large numbers of silver grains were observed in the interstitium, bronchioles, and alveolar sacs 20 minutes after the injection, and lamellar distribution of the grains was observed on the ciliary surface. The numbers of silver grains in the interstitium and bronchioles had decreased 3 hours after the injection of 125I-IMP, but the numbers of silver grains in the alveolar spaces had not. Although small numbers of silver grains remained in both the bronchioles and alveolar sacs 24 hours after the injection, most of them had washed out. Confocal laser scanning microscopy is considered to be a useful procedure for studying the distribution of radioisotopes by microautoradiography, because it allows clear autoradiographs to be obtained in which tissues and silver grains are perfectly matched and all silver grains are in focus.

Animals↗

PubMed2000

Technetium-99m MIBI single photon emission computed tomography as an indicator of prognosis for patients with lung cancer-preliminaly report.

PURPOSE: We performed technetium-99m hexakis-2-methoxyisobutylisonitrile (Tc-99m MIBI) single photon emission computed tomography (SPECT) in 23 patients with primary lung cancer between July 1993 and March 1996. We evaluated the relationships among the uptake ratio, retention index and the prognosis after radiation therapy and/or chemotherapy. MATERIALS AND METHODS: Tc-99m MIBI SPECT was performed at 30 minutes and at 3 hours after intravenous injection of 600 MBq of Tc-99m MIBI with three gamma camera detectors (GCA-9300A/HG) on transverse SPECT images. Regions of interest were set in the area of abnormal uptake of Tc-99m MIBI and in the contralateral normal lung. The ratio of uptake in the lesion to that in the contralateral normal lung was obtained on early images (early ratio; ER) as well as delayed images (delayed ratio: DR). The retention index (RI) was calculated as follows: RI = (DR - ER)/ER x 100. The ratio was compared with survival time and prognostic factors. RESULTS: There was no correlation between ER and DR. The patients with high RI survived longer than those with low RI (median survival, 19.4 months vs. 9.4 months; p = 0.0104 by the Mantel-Cox test). CONCLUSION: These results suggest that RI is the most useful among Tc-99m MIBI indices of primary lung cancer in predicting prognosis.

Adult↗

PubMed2000

Galectin-3 expression in various thyroid neoplasms and its possible role in metastasis formation.

Galectin-3 is a member of the beta-galactoside-binding protein family that plays an important role in cell-cell adhesion and in cell-matrix interaction. We have examined the expression of galectin-3 in normal, adenomatous, and malignant thyroid tissues and also in metastatic lesions. Galectin-3 was rarely expressed in normal thyroid tissue but was abundant in the cytoplasm of the neoplastic lesions. Among neoplastic lesions, galectin-3 was expressed to a greater extent in follicular carcinomas than in follicular adenomas and was present in greater amounts in papillary carcinomas than in follicular adenomas or carcinomas. Primary lesions of papillary carcinoma with metastasis contained significantly higher concentrations of galectin-3 than tumors of this type without metastases. However, the expression of galectin-3 was significantly decreased in metastatic lesions in the lymph nodes compared with their primary lesions. From these results, we assumed that galectin-3 works in different ways at different stages of thyroid neoplasm proliferation. Among primary tumors, galectin-3 expression is significantly different in 3 histological types. However, the continuity of progression among these tumors is not yet proven. In later stages, decreased expression of galectin-3 may aid the release of cancer cells from the primary lesions for invasion and metastasis.

Adenocarcinoma, Follicular↗

PubMed2000

A case of local recurrent pheochromocytoma: usefulness of I-123 MIBG early SPECT and maximum intensity projection images.

It has been reported that 10% of patients with pheochromocytoma experience recurrence despite surgery. The authors administered I-123 MIBG to patients with recurrent pheochromocytoma and found that early images are more useful than delayed images to detect recurrence. Early imaging with I-123 MIBG is useful for postoperative follow-up studies in patients with pheochromocytoma and those with possible tumor recurrence.

3-Iodobenzylguanidine↗

PubMed2000

Tc-99m PMT whole-body scintigraphy for evaluated of therapeutic effect and for monitoring bone metastasis in a patient with hepatocellular carcinoma.

Detection of metastatic lesions by bone scintigraphy is highly sensitive but has a low rate of specificity. Often bone metastases from hepatocellular carcinoma are not detected by bone scintigraphy because of low uptake or a photopenic area in the tumor. In contrast, Tc-99m Sn-N-pyridoxy-5-methyltryptophan (Tc-99m PMT) whole-body scintigraphy reflects tumor viability, and the specificity of detection is so high that tumor structure can be shown well. Tc-99m PMT whole-body scintigraphy was helpful for evaluating the response to therapy and monitoring the course of the patient described here with bone metastasis from hepatocellular carcinoma.

Bone Neoplasms↗

PubMed2000

Salutary antiarrhythmic effect of combining a K channel blocker and a beta-blocker in a canine model of 7-day-old myocardial infarction.

We sought to examine whether the antiarrhythmic effect of E4031 (E), or I(Kr) channel blocker, is affected by beta-adrenergic stimulation using isoproterenol (Iso) or by beta-adrenergic blockade (betaB) using, ONO1101, in a canine myocardial infarction model. Electrophysiologic studies were performed in 10 dogs with 7-day-old myocardial infarctions. Local QT intervals were measured at 47 sites on the infarcted myocardium using a mapping electrode. QT dispersion (QTd), as defined by the coefficient of variation of QT intervals, was obtained. Inducibility of ventricular arrhythmias was examined by programmed stimulation. These procedures were repeated during administration of E, E + Iso, and E + betaB. The effect of prolonging local QT intervals by E was counteracted by Iso, and was accentuated by betaB. The amount of prolongation was dependent on the baseline QT intervals, and QTd showed a tendency to decrease with E, to increase with E + Iso, and significantly decreased with E + betaB. Ventricular tachyarrhythmias were induced in a half of dogs with E + Iso, but were not induced with E + betaB. In the presence of adrenergic activation, I(Kr) blockers may exhibit a decreased antiarrhythmic effect. Beneficial synergism can be expected when an I(Kr) blocker is combined with a beta-blocker in the subacute phase of myocardial infarction.

Adrenergic beta-Antagonists↗

PubMed1999

Esophageal varices before and after endoscopic variceal ligation: evaluation using helical CT.

The purpose of this study was to demonstrate the utility of helical CT in assessing the therapeutic effects of endoscopic variceal ligation (EVL). Twenty-four patients with esophageal varices were examined. Helical scanning was initiated 60 s after intravenous injection (Iopamidol 300 mgI/ml, total 120 ml, 3 ml/s) was started. Esophageal varices were clearly depicted as high-density areas. Multiplanar reformation and 3D images demonstrated collateral circulation three-dimensionally. After EVL, mucosal high-density areas had diminished markedly, but collateral veins around the esophagus, and gastro- and/or spleno-renal shunts, were unchanged in all patients. Of 21 patients with collateral circulation, esophageal varices recurred endoscopically in 6 patients within 12 months. In 3 patients without collateral circulation, esophageal varices did not recur within 12 months. From these findings, we conclude that helical CT is a useful method for assessing the therapeutic effects of EVL.

Collateral Circulation↗

PubMed1999

[Evaluation of 99mTc-MAG3 (mercaptoacetyltriglycine) renography for pediatric patients].

It is difficult to evaluate renal function with 99mTc-MAG3 renography in both adult and pediatric patients. We examined 109 pediatric patients with various renal diseases using 99mTc-MAG3 renography. Tenal diseases were classified as follows: 9 vesicoureteral reflux, 4 ureteropelvic junctional stenosis, 3 double pelvis, 23 hydronephrosis, 4 glomerulonephritis, 4 nephrotic syndrome, 24 hemolytic uremic syndrome, 10 others; and 24 patients without abnormal findings on other examinations. After hydration and sedation, 100-200 MBq of 99mTe-MAG3 was injected intravenously. All patients were placed in the supine position, and dynamic data acquisition at 12 sec/frame x 100 frames was performed from the back. The renograms were prepared with the ROIs (regions of interest) set to include the entire kidney. Tmax and T1/2 of renograms were measured for 26 kidneys with no abnormal findings. The correlations between Tmax or T1/2 and age (days after birth) were determined by a linear or logarithmic function. The logarithmic function (Y = 7.49 - 0.56 logeX, r2 = 0.134) yielded a higher correlation than did the linear function (Y = 5.16 - 0.00194X, r2 = 0.089) between Tmax and age. For T1/2 and age (days after birth), the linear function (Y = 8.07 - 0.00451X, r2 = 0.222) yielded a higher correlation than the logarithmic function (Y = 11.9 - 0.986 logeX, r2 = 0.192). Our findings suggest that prolonged Tmax is normalized more rapidly than T1/2 after birth in infants. A delayed excretion phase is not suggestive of renal dysfunction, but is characteristic of renograms in pediatric patients. Abnormality was detected in all patients with hydronephrosis using 99mTc-MAG3 renography. On the other hand, a quantitative study was required because renography detected no abnormality for some of patients with disorders of renal parenchyma.

Adolescent↗

PubMed1999

[Quantitative assessment of 201Tl-SPECT in tumors of bone and soft tissue].

201Tl-SPECT was performed to diagnose the malignancy of bone and soft tissue tumors by visual and quantitative assessment in 48 patients (17 malignant lesions and 31 benign lesions). SPECT images were obtained in the early phase (15 min after injection) and the delayed phase (240 min). By visual assessment a tumor was considered malignant if high accumulation was found in the tumor in the early phase and the accumulation was confirmed in the delayed phase. Tumors which did not meet these criteria were considered benign. For quantitative assessment, the ROI (region of interest) accumulation ratios of the tumor to the contralateral normal tissue in the early phase (ER) and in the delayed phase (DR), the ROI accumulation ratio of the delayed phase to the early phase of the tumor (Td/Te), and the ROI accumulation ratio of the delayed phase to the early phase of the contralateral normal tissue (Nd/Ne) were obtained. Sixteen patients with malignant tumors each had a high accumulation each but 12 of 31 benign lesions had no high accumulation on visual assessment. Furthermore, the accuracy was 85.4%, sensitivity 94.1%, and specificity 80.6%. Quantitative assessment was performed for 36 cases of high accumulation. The ER of malignant and benign lesions was 5.51 +/- 3.73 and 2.75 +/- 2.17, respectively, and the ER of malignant lesions was significantly higher than that of benign lesions. The DR did not demonstrate a significant difference. If the tumor having an ER greater than 3.9 was assumed to be malignant, the accuracy for differentiating malignant lesions from benign lesions was 85.4%. The Td/Te of benign lesions (0.97 +/- 0.28) was higher than that of malignant lesions (0.77 +/- 0.09). The Nd/Ne of normal tissue which contained muscles in both lesions were higher than 1.4. In conclusion, 201Tl-SPECT was very useful for the differential diagnosis of benign or malignant bone and soft tissue tumors. The ER was important for quantitative assessment, but a delayed image was necessary for visual assessment.

Adolescent↗

PubMed1998

Bystander effect-mediated therapy of experimental brain tumor by genetically engineered tumor cells.

Transfer of the herpes simplex virus-thymidine kinase (HSV-tk) gene, followed by administration of ganciclovir (GCV), generates the "bystander effect," in which HSV-tk-negative wild-type cells, as well as HSV-tk-expressing cells, are killed by GCV. To eradicate an intracranial tumor by this bystander effect, we injected the tumor cells transduced with the HSV-tk gene (TK cells) in the vicinity of the preimplanted wild-type tumor and then administered GCV. Wild-type 9L-gliosarcoma cells (1 x 10[5]) were implanted into the brain of syngeneic Fisher rats. On the next day, rats were injected with TK cells (1 x 10(5) or 3 x 10[5]) or medium alone at the same brain coordinate and then treated with GCV or saline. Administration of GCV significantly prolonged the survival of the rats injected with TK cells compared with that injected with medium alone (p < 0.01). Reduction in tumor size and retardation of tumor growth were observed by serial magnetic resonance imaging in the rats that received the combination of TK cells and GCV. The results show that the bystander effect is also achieved in vivo even when TK cells and wild-type cells are not simultaneously implanted. This treatment modality circumvents potential risks accompanied with in vivo gene transfer. Because there remained substantially no HSV-tk-positive cells in the recurrent tumors, this modality offers a "safe" therapeutic strategy against human malignant gliomas.

Animals↗