Biomedical subjects

K Sueyoshi

Publications and source records attributed to K Sueyoshi.

95 records · Page 6Linked to original sources

PubMedDate not supplied

Induction of acquired immunity in rats that have eliminated intracranial gliosarcoma cells by the expression of herpes simplex virus-thymidine kinase gene and ganciclovir administration.

We examined a possible antitumor response against 9L rat gliosarcoma cells induced by the expression of the herpes simplex virus-thymidine kinase (HSV-TK) gene and the ganciclovir (GCV) system. Based on the amount of the major histocompatibility complex (MHC) class I antigens expressed on 9L cells transduced by the HSV-TK gene (9L/HSV-TK) we selected two clones (clones H and L), which represent high and low expressors of class I antigens, respectively. By means of serial magnetic resonance imaging we followed the change of tumor volumes of each clone in syngeneic rats, and found that the intracranial tumor growth was inversely correlated with the expression of MHC class I antigens, although in vitro growths of the clones remained unchanged. Moreover, histological examination revealed significant lymphocyte infiltration in the 9L/HSV-TK tumor of high MHC expression but not in the wild-type tumor. The therapeutic effect of GCV on them was not different, but we observed a prolonged survival of the rats which had eliminated 9L/HSV-TK clone L tumors by the treatment of GCV and were rechallenged with the same cells compared with the survival of naive rats inoculated with clone L cells. These data collectively suggest that the immune response operates even in the brain previously described as an immunologically privileged site.

Animals↗

PubMedDate not supplied

Three-dimensional computed tomographic angiography of pulmonary vessels.

OBJECTIVE: To assess the image quality of multiple threshold display (MTD) as a new technique for generating three-dimensional (3D) pulmonary computed tomographic (CT) angiographic images. METHODS: We used MTD, a type of shaded surface display (SSD) offering the selection of multiple thresholds and transparencies, to reconstruct 3D-CT angiograms from enhanced helical CT data sets in 33 patients with lung disease. In MTD, eight thresholds of CT values are selected, and transparency is assigned to each. The selected voxels, ranging from -600 to 1,000 Hounsfield Units, were divided into eight classes, and transparency ranging from 0 to 100% was assigned to each. The CT scanner employed was a Toshiba Xvigor. MTD and SSD images were generated by using an Xtension with a Sun SPARC station 20, and they were compared by two radiologists. RESULTS: The image quality of MTD images was superior to that of SSD images (p < 0.01), because the MTD images demonstrated clearly both the major and small vessels. CONCLUSION: MTD is a useful technique for 3D pulmonary CT angiography.

Female↗

PubMedDate not supplied

Three-dimensional display of the bronchi using helical CT.

The purpose of this study was to evaluate the clinical usefulness of three-dimensional (3D) images of the bronchi obtained using helical CT. Thirteen patients with lung cancer, one with tracheal diverticulum, and one with bronchial amyloidosis were examined. The CT scanner employed was the Toshiba Xforce. The helical CT scan cycle consisted of 20 continuous rotations, each requiring 1.5 sec, for a total scanning time of 30 sec. Scans were obtained using a 5-mm X-ray beam width, a 5-mm/1.5 sec couchtop sliding speed, and a 2-mm reconstruction interval. 3D images were reconstructed using a CEMAX VIPstation. The optimal lower and upper threshold CT values for 3D images of the bronchi were -650 and -100 HU, respectively, and 3D images clearly depicted endobronchial lesions. Cartilage crescents were also demonstrated, but longitudinal and circular mucosal folds could not be visualized. In conclusion, 3D images of the bronchi acquired using helical CT were useful in evaluating endobronchial lesions.

Adult↗

PubMedDate not supplied

Three-dimensional display of pulmonary nodules using helical CT.

To evaluate the clinical usefulness of three-dimensional (3D) images of pulmonary nodules acquired using helical CT, 3D reconstructions were performed in 32 patients using a CEMAX VIPstation. The CT scanner employed was the Toshiba Xforce. Helical CT data were acquired using up to 20 continuous 1.5-sec rotations with an X-ray beam width of 5 mm and a couchtop movement speed of 5 mm/1.5 sec. Axial images were reconstructed at a section interval of 2 mm. The optimal lower and upper threshold CT values for 3D images were as follows: 1) solid pulmonary nodule (-700--400/-100 HU), 2) tumor invading pleura or chest wall (-700--400/-200 HU), 3) pulmonary nodule with cavity (-700--400/50 HU), 4) small pulmonary nodule (< 10 mm) (-750--650/-100 HU), and 5) arteriovenous malformation (180/500 HU). In all cases, it was possible not only to demonstrate abnormal findings three-dimensionally but also to grasp anatomical relationships among the pulmonary nodule, bronchi, vessels, and chest wall.

Adult↗

PubMedDate not supplied

In vitro uptake and release of TI-201 and Tc-99m MIBI in cultured tumor cells and effect of anticancer drug.

201Tl is useful in the diagnosis of tumor malignancy determined by the grade of washout rate to normal tissue, especially in lung tumors and thyroid tumors. 99mTc-MIBI, a tracer of myocardial blood flow, is also a tumor tracer. We examined whether the growth of tumor cells is related to the uptake and release of these tracers in cultured tumor cells. Cultured tumor cells (HeLa cells and squamous cell carcinomas derived from human lung cancer) were incubated for 60 min with 10 kBq of either tracer for the kinetic study of cellular uptake. They were additionally incubated for 90 min with cold medium for the kinetic study of cellular release. These cells cultured with various concentrations of actinomycin D (ACD) or CDDP were used to examine the correlation between the cellular growth and kinetics of these tracers. The cellular release of 201Tl increased relative to the concentration of added ACD or CDDP in both cell types. In contrast, the cellular release of 99mTc-MIBI was not changed by the addition of ACD in HeLa cells. In conclusion, 201Tl showed a slower washout rate in high-growth tumor cells than in low-growth tumor cells; thus, it could act as an indicator of tumor malignancy by assessing its washout rate.

Antineoplastic Agents↗