Biomedical subjects

R Hamazoe

Publications and source records attributed to R Hamazoe.

58 records · Page 4Linked to original sources

PubMedDate not supplied

The effect of angiotensin II on blood flow in tumours during localized hyperthermia.

The selective enhancement of drug delivery to tumours is an important factor in the effectiveness of thermochemotherapy as well as in standard normothermal chemotherapy. We have attempted to clarify experimentally using AH 100B tumour-bearing rats whether or not a selective increase in blood flow in tumours can be produced under specific conditions of local hyperthermia by administration of angiotensin (AGT II). AGT II (2 micrograms/kg/min) produced an elevation of blood pressure (ca. 150 mm Hg) when local hyperthermia, at 41, 43, and 45 degrees C, was induced. Furthermore, at 41 and 43 degrees C a selective increase in blood flow in tumours resulted from the AGT II-induced hypertension. By contrast, a decrease in blood flow was observed at 45 degrees C both in tumour and in muscle. These results indicate that AGT II-induced hypertension and the resultant selective increase in drug delivery to tumours during the initial phase of heating may result in an augmentation of the anticancer effects of thermochemotherapy.

Angiotensin II↗

PubMedDate not supplied

Attempt to induce total-body hyperthermia by whole-abdominal hyperthermia using a radiofrequency capacitive-heating system: an experimental study in dogs.

The effects of whole-abdominal hyperthermia (WAH), using an 8 MHz radiofrequency capacitive-heating system, on the intraperitoneal and extraperitoneal distribution of heat and on the functions of visceral organs were studied. Eight female mongrel dogs were divided into two groups. Five were infused and three were not infused intraperitoneally with physiological saline. The mean increase in systemic temperature during WAH was 6.4 degrees C for the saline-infused group and 5.1 degrees C for the non-infused group. The systemic temperature reached 40 degrees C about 50 min after the start of heating in four of five animals in the saline-infused group; three of the four animals died, and in these the maximum temperature of the liver exceeded 43.5 degrees C. The infusion of saline into the peritoneal cavity may facilitate the elevation of systemic temperature. The effects on the liver of WAH were very marked, as analysed by biochemical and histological techniques. Visceral organs tolerated heating to less than 43 degrees C by WAH alone. It appears that elevation of the systemic temperature to 40.5 degrees C or more can be safely achieved under conditions where the temperature in the peritoneal cavity is kept below 43.5 degrees C during WAH.

Abdomen↗

PubMedDate not supplied

Intrahepatic cholangiocarcinoma with a long-term survival of 12 years after surgical resection: report of a case and review of the literature.

The prognosis of primary liver cancer, especially cholangiocarcinoma, is extremely poor. A long term, 12 years survivor of intrahepatic cholangiocarcinoma arising in a local dilatation of the intrahepatic bile duct is presented. A 40-year-old male patient was presented with recurrent upper abdominal pain, fever, and jaundice. Computed tomography revealed a localized duct dilatation, and ultrasound clearly demonstrated a tumor mass arising within the bile duct. At surgery in March, 1982, the tumor mass was resected and histologically confirmed as a well differentiated papillary adenocarcinoma arising. In March, 1994, the patient is alive and cancer-free, 12 years after surgical resection. To our knowledge, there has been no report on a patient surviving more than 10 years after initial treatment. This case suggests that a localized cystic dilatation of the intrahepatic-bile duct on imaging modalities may harbor a bile duct carcinoma, and this in turn may contribute to early diagnosis of carcinomas and improved long term survival.

Adult↗

PubMedDate not supplied

Cytological evaluation of the effects of chemotherapy on metastatic liver cancer.

We present a method for the cytological evaluation of the therapeutic effects of various treatments on unresectable metastasis in the liver from colorectal cancer. A degeneration index (DI) for cancer cells obtained by aspiration was determined in 17 patients before and after treatment. The relationships of the rate of tumor reduction and of the post-treatment survival period to the treatment-induced changes in DI were studied. The treatment-induced change in DI was represented by the difference between the pretreatment DI and the posttreatment DI. The treatment-induced change in DI was significantly correlated with the rate of tumor reduction (r = 0.794, P < 0.001). The survival rate was significantly higher in patients with higher changes in DI than in patients with lower changes (P < 0.05). The change in the DI of cancer cells seems to be a useful parameter for evaluating the effects of chemotherapy on unresectable liver metastases from colorectal cancer.

Aged↗