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A Moriyama

Publications and source records attributed to A Moriyama.

93 records · Page 6Linked to original sources

Angioscopy in transluminal balloon and laser angioplasty in the management of chronic hemodialysis fistulae.

In chronic hemodialysis patients, there is the major problem of occlusion in the arteriovenous fistulae. To investigate this problem, the authors have developed angioscopy for examination and detection of occlusion developing to allow early use of transluminal balloon angioplasty (PTA) or laser angioplasty and prevent occlusions. The authors have examined 27 patients using a 2.7 mm diameter Olympus flexible angioscope and 9F sheath, following-up with a 4 mm balloon catheter (BARD) or SLT Nd-YAG laser. PTA was performed for 25 cases, with 19 demonstrating after one session patency lasting 9 months to date. Three cases revealed restenosis and have each received three PTA sessions. Laser angioplasty was performed in one case of 15 cm chronic occlusion, with subsequent PTA successfully enabling hemodialysis. Angioscopically, the authors were able to observe the various rest-forms within the shunt and detected the mural thrombus attached to the punctured pore. Both circumferential and valvular stenoses were observed. Initially after laser angioplasty, rough irregularity and a mural thrombus in the vessel was observed, but 2 months later, the vessel lumen had become smooth, probably due to intimal growth. Thrombus is acute stenosed cases were clearly observed. Angioplasty enabled new observations in the A-V fistulae, which allows investigation of the mechanism of stenosis or occlusion and enables an extended use of the hemodialysis blood access.

Angioplasty, Balloon↗

cAMP stimulates the bystander effect in suicide gene therapy of human choriocarcinoma.

In gene therapy, tumor cells expressing herpes simplex virus thymidine kinase (HSV-tk) are sensitive to ganciclovir (GCV) and HSV-tk positive cells exposed to GCV are lethal to adjacent HSV-tk negative cells. This phenomenon has been called the bystander effect, and the gap junction is thought to mediate it. In this study, sensitivity to GCV and bystander effect in a human choriocarcinoma cell line, BeWo, transfected with HSV-tk were investigated. Furthermore, the effect of 8-bromo-cAMP on bystander effect and connexin40 gene transcription were examined. HSV-tk positive cells were sensitive to GCV at the concentration of 10 micrograms/ml in a time-dependent manner. The growth of HSV-tk negative cells was inhibited when the population of cultured cells contained more than 10% HSV-tk positive cells and 8-bromo-cAMP enhanced bystander effect. 8-bromo- cAMP increased connexin40 mRNA expression and gap junctional intercellular communication.

8-Bromo Cyclic Adenosine Monophosphate↗