Biomedical subjects

Y Onoyama

Publications and source records attributed to Y Onoyama.

At least 19 recordsLinked to original sources

PubMed1997

Hypersensitivity reactions to cisplatin following multiple uncomplicated courses: a report on two cases.

Two patients with ovarian cancer who had received multiple courses of cisplatin without complications experienced hypersensitivity reactions to cisplatin: one, involving intrahepatic artery infusion, manifested general erythema, dyspnea, and hypotension; the other, involving intravenous infusion, manifested abdominal pain, general erythema, and fever. When platinum-containing agents are administered, patients should be closely monitored for hypersensitivity reactions, even in previously uncomplicated cases.

Adult↗

PubMed1997

Malignant fibrous histiocytoma of the temporal bone with endocranial extension.

Cranial malignant fibrous histiocytomas are rare tumors. Most are hypervascular, destructive masses that are similar to other malignant lesions and to malignant fibrous histiocytomas found elsewhere in the body. We describe a myxoid malignant fibrous histiocytoma of the temporal bone, possibly of dural origin, with features that more closely resembled a meningioma at CT, MR imaging, and angiography.

Adult↗

PubMed1996

Experimental selective segmental ablation of rat liver by transportal ethanol injection.

For use in the treatment of malignant hepatic tumors, we undertook selective segmental ablation of the liver by transportal ethanol injection, first studying its efficacy and safety in rats. We forced a 4:1 mixture of ethanol and contrast medium from a syringe into hepatic tissues via a branch of the portal vein in 80 Wistar rats. The amount of ethanol injected was from 0.05 to 0.60 ml. Soon after the injection, the hepatic segment treated with ethanol was yellowish-white with a distinct outline. Two to three weeks after the injection, the segment was completely necrotic. The findings when a mixture of ethanol and India ink was injected suggested that the necrosis was a direct result of the ethanol. The portal branch into which the injection was made was completely obstructed immediately after the injection. The maximum ethanol concentration in the peripheral blood was 0.4 mg/ml. No histological changes were found in any other organ. Liver and kidney function was almost unaffected. This technique might be useful clinically for the treatment of malignant hepatic tumors.

Animals↗

PubMed1996

Promotive action of acylated ascorbate on cellular DNA synthesis and growth at low doses in contrast to inhibitory action at high doses or upon combination with hyperthermia.

Effects of 6-O-palmitoyl ascorbate (ascorbate) developed to increase the antitumour activity of ascorbic acid on DNA synthesis and proliferation of Ehrlich ascites tumour cells were investigated. Treatment of the cells with the acylated ascorbate at 25-50 microM for 1 h resulted in no effect on DNA synthesis, assayed by pulse incorporation of [3H]thymidine after a culture period of 20 h, but led to 49%-87% enhanced DNA synthesis after 4 days, suggesting that long-term culture is required for promotion by ascorbate to occur. At a dose as high as 75 microM acylated ascorbate, however, cellular DNA synthesis was 64% inhibited after 20 h and 99% after 4 days. The results suggest that acylated ascorbate exhibits a dual action on DNA synthesis: promotion at low doses and inhibition at high doses, both of which are potentiated in a time-dependent manner. In contrast to the above-mentioned results at 37 degrees C, acylated ascorbate at 25-75 microM inhibited but did not promote DNA synthesis at 42 degrees C whatever the culture period. Similar results were exhibited when proliferation of cells cultured for a long period was investigated. At 37 degrees C, 50 microM acylated ascorbate increased the number of the cells to 3.6 times the control values after 8 days and to 1.9 times after 11 days; in contrast, a 75-microM dose decreased the cell number considerably. Combination with hyperthermia (42 degrees C) suppressed the increase and cell growth was completely inhibited at 75 microM.

Acylation↗

PubMed1996

Use of recombinant tissue-type plasminogen activator to treat massive pulmonary embolism after cesarean section: a case report.

A 30-year-old primigravida, delivering by cesarean section, went into shock with cardiac arrest due to pulmonary thromboembolism. Thrombolytic therapy with recombinant-tissue-type plasminogen activator (rt-PA) induced a rapid improvement in both the hemodynamic and respiratory conditions. This case shows the marked efficacy of rt-PA in treating massive pulmonary thromboembolism. Close attention must be given to the patient in such a case, however, because the risk of hemorrhagic complication exists.

Adult↗

PubMed1995

Comparison of bone scans, parathyroid hormone levels and bone mineral densities in hemodialysis patients.

We have evaluated bone scans, parathyroid hormone (PTH) levels and bone mineral densities (BMDs) of hemodialysis (HD) patients. The bone scans were grouped into 4 types (type 1-4). Type 1 showed a diffusely high activity of the tracer in the whole skeleton especially in the skull: secondary hyperparathyroidism pattern. Type 2 showed high background activity, the same pattern as osteomalacia. Type 3 was a mixture of types 1 and 2. Type 4 was almost normal. The PTH levels of type 1 were higher and the radius BMDs were lower than those of the other types. The radius BMDs in one third of type-2 patients were lower than the normal range. A comparison of bone scans, PTH and BMDs helps to evaluate bone changes in HD patients.

Adult↗

PubMed1995

Central giant cell granuloma of the temporal bone.

We present two cases of central giant cell granuloma in the temporal bone. CT showed an enhancing tumor causing a smoothly margined temporal squamosa and floor of the middle fossa. External carotid angiograms showed tumor stain mainly supplied by the temporal branches of the internal maxillary artery. In one case, MR images showed a hypointense mass on both T1- and T2-weighted images that was thought to reflect the pathologic character of this lesion.

Adult↗

PubMed1995

[Transjugular intrahepatic portosystemic shunt for patients with hepatoma].

Nine patients with hepatoma, 5 with massive ascites, 3 with rupture of esophageal varices and 1 with hematoemesis, successfully underwent TIPS without technical complications. Two of the patients died 3 and 5 months, respectively, after TIPS due to hepatic failure and/or tumor extension. Another patient in whom hepatoma ruptured 1 month after TIPS was experienced. It is concluded that TIPS is a useful and safety treatment for portal hypertension even in patients with hepatoma which was not existed through the puncture route. However TIPS should be performed in patients in whom hepatoma has been controlled by hepatic embolization and/or ethanol injection therapy.

Aged↗

PubMed1995

Enhanced inhibitory effects of hyperthermia combined with ascorbic acid on DNA synthesis in Ehrlich ascites tumor cells grown at a low cell density.

Effects of hyperthermia and cell densities on inhibitory activity of ascorbic acid on DNA synthesis in Ehrlich ascites tumor cells were studied. When cells at a low density of 5 x 10(3)/ml were treated with 75 microM ascorbic acid for 1 h, DNA synthesis was inhibited after treatment at 37 degrees C and the inhibition was significantly enhanced at 42 degrees C. At a cell density as high as 1 x 10(5)/ml, however, inhibition did not occur at 37 degrees C or 42 degrees C. In contrast, dehydroascorbic acid was inactive even at a low cell density under similar conditions. Inhibitory effects of ascorbic acid on DNA synthesis were also markedly enhanced by treatment at 40 degrees C. DNA synthesis was not inhibited in the absence of the drug. Furthermore, mice transplanted with cells treated with a combination of 75 microM ascorbic acid and hyperthermia at 42 degrees C, considerably prolonged their survival time in comparison with untreated cells. Addition of ascorbic acid to hyperthermia is suggested to be an advantageous treatment for cancer.

Animals↗

PubMed1994

[MR pyelography using fast spin echo technique in hydronephrosis].

MR pyelography using the fast spin echo technique and and a body coil were performed in ten patients with hydronephrosis. In all cases, pyelograms of the dilated urinary tract were obtained by this method, although they were obtained in only two cases by drip infusion pyelography. MR pyelography is an effective method with which to obtain images of dilated urinary tract non-invasively, and in a relatively short time. This method was also useful to evaluate intraureteral structure.

Adolescent↗

PubMed1994

[Usefulness of MR cholangiography with flex coil].

Fast SE MR cholangiography was performed in 10 healthy volunteers and 10 patients with biliary disease, using body, shoulder and flex coils. Surface coils provided better images than the body coil. Although high SNR images were obtained near surface coils, signal intensity decreased in areas distant from the shoulder coil. The flex coil greatly improved image quality, especially in intrahepatic bile ducts, compared with the shoulder coil. The application of a flex coil to MR cholangiography is a highly useful method to evaluate the biliary system.

Adult↗

PubMed1994

In vivo radiosensitizing effect of nitroimidazole derivative KIN-804.

PURPOSE: In vivo characteristics of 2-nitroimidazole-1-methylacetohydroxamate (KIN-804), which is a newly developed hypoxic cell radiosensitizer, are presented. METHODS AND MATERIALS: The toxicity, pharmacokinetics, and radiosensitizing effect of KIN-804 were studied by in vivo experiments using C3H/He mice bearing the SCC-VII tumor. Results were compared with misonidazole (MISO). RESULTS: LD50(7) of KIN-804 and MISO were 3200 mg/kg and 2000 mg/kg, respectively. The peak of concentrations of KIN-804 in the tumor occurred 20 min after intraperitoneal injection and reached about 62% of the maximum concentration in the blood. The concentrations in brain and sciatic nerve were very low and clearance from sciatic nerve was rapid. Enhancement ratios of KIN-804 calculated using the growth delay method were 1.22, 1.50 and 1.71 at doses of 50, 100, and 200 mg/kg, respectively, compared with 1.36 for MISO at a dose of 100 mg/kg. In the TCD50 assay, enhancement ratios at a dose of 200 mg/kg were 1.69 for KIN-804 and 1.52 for MISO, respectively. CONCLUSION: KIN-804 is a promising radiosensitizer since it shows less toxicity and higher radiosensitizing activity than MISO.

Animals↗

PubMed1994

Intradural chordoma: case report and review of the literature.

Chordomas are rare neoplasms arising from notochordal remnants found predominantly in the clivus and the sacrococcygeal regions. Most clivus chordomas show extradural extension and bone destruction. Such a tumour can rarely be intradural. This report is concerned with the radiological findings in prepontine intradural chordoma.

Brain Neoplasms↗

PubMed1994

[Usefulness of 99mTc-PMT SPECT and 18F-FDG PET in diagnosing orbital metastasis of hepatocellular carcinoma].

We reported a case in which 99mTc-PMT scintigraphy was useful in diagnosing orbital metastasis of HCC. The case involved a 70 y.o. male, who had undergone nine transcatheter arterial embolizations over two years because of HCC and who had a past history of gastric cancer. The patient had complained of headache and visual disturbance for two months. Cranial CT and MRI studies showed a large homogeneous mass with remarkable bone destruction in the right lateral orbital wall. Because AFP was elevated, orbital metastasis of HCC was suspected, and 99mTc-PMT scanning was performed. On the planar and SPECT images, very high uptake was found in the right orbital tumor. The FDG-PET study showed remarkable hypermetabolism in the medial portion of tumor and follow-up MRI revealed that the tumor had expanded and invaded to the medial side of the orbit. 99mTc-PMT scanning was critical in diagnosing this case of orbital metastasis, and FDG-PET imaging was useful in determining the most active portion of the tumor.

Aged↗

PubMed1994

[A case of mesenteric panniculitis: comparing the findings of 67Ga scintigraphy with pathological results].

We report a case of mesenteric panniculitis where we compared the findings of 67Ga-citrate (Ga) scintigraphy with pathological results. The patients, a 75-year-old man, was hospitalized for examination of low abdominal mass. After hospitalization he developed high CRP levels. A Ba enema revealed serrated intestinal walls and a thick fat density, the margins of which were distinct, as judged from abdominal CT scans. Therefore we suspected a mesenteric panniculitis. Since the patient did not improve under conservative treatment for three months, surgery was performed a day after Ga scintigraphy which showed the abnormal uptake in the abdominal mass, which was removed. The radioactivity of several tissue slices from the resected specimen containing the affected part which had been described inflammatory in the pathological examination showed very high radioactivity. This disease is usually diagnosed from the typical findings of Ba enema and CT scan. But, when an extraordinary abdominal accumulation presents, one should think of performing a Ga scan as an additional diagnostic parameter.

Aged↗

PubMed1994

Angiogenic activity of human villi and decidua in the first trimester of pregnancy.

Angiogenic activity in the extracts of human villi and decidua in the first trimester of pregnancy was examined using chorioallantoic membrance assay. Blood vessel density on the chorioallantoic membrane increased greatly with the addition of villi extract, and slightly by decidua extract. Neovascularization with a spoke wheel appearance was induced by both villi and decidua, and this response pattern by the villi was stronger than that by the decidua. Maternal serum did not induce any vascular response. These results suggested that angiogenic activity was present both in the villi and decidua in the first trimester of pregnancy and that the villi activity was stronger than the decidua.

Blood Vessels↗

PubMed1994

[Transjugular intrahepatic portosystemic shunt--early experience in eleven liver cirrhosis patients].

Eleven liver cirrhosis patients with variceal bleeding and/or ascites were treated by transjugular intrahepatic portosystemic shunt. Four of the patients were combined with hepatoma, and 2 had portal thrombosis. Ten of the patients were successfully achieved TIPS, but one patient who had portal thrombosis was failed because of portal vein occlusion; success rate of 90%. An average decrease of 14mmHg in portal vein pressure was measured in the 10 patients. All of the successful patients including 4 with hepatoma were observed the disappeared or diminished varices and ascites without technical complication. Mild encephalopathy was encountered in 2 patients but who responded well to medical therapy. Three dimension MRA before TIPS was helpful for understanding the anatomical relationship between portal vein and hepatic vein. It is concluded that TIPS is an effective and safe treatment, indicating for the patients who have uncontrollable variceal bleeding and/or ascites even with hepatoma.

Adult↗

PubMed1994

Effect of hyperthermia on tumor uptake of radiolabeled anti-neural cell adhesion molecule antibody in small-cell lung cancer xenografts.

UNLABELLED: This study was performed to examine the effect of hyperthermia on the intratumor accumulation of a monoclonal antibody (Mab) in an animal model. Mab NE150 (IgG1) recognizes the neural cell adhesion molecule (NCAM) expressed by human small-cell lung cancer (SCLC) cells. METHODS: Athymic mice inoculated with NCI-H69, an SCLC cell line, received an intravenous injection of 125I- and 111In-NE150 and the serial changes of the biodistribution were determined. Furthermore, athymic mice bearing NCI-H69 were either sham-treated or treated by a single hyperthermia at 42 degrees C or 43 degrees C for 1 hr, with the tumor-bearing leg in a water bath using pentobarbital anesthesia. Immediately after heating, the mice were given an intravenous injection of radiolabeled NE150, and the biodistribution was examined at 24 and 48 hr. RESULTS: NE150 localized well in the transplanted tumor when compared with a control Mab. In mice treated at 43 degrees C, there was a 1.34- to 1.67-fold increase in the tumor uptake of 125I- and 111In-NE150 compared to sham-treated mice at both 24 and 48 hr. In addition, a 1.84- to 2.22-fold increase of the tumor-to-blood ratio was demonstrated, since radiolabeled NE150 cleared faster from the circulation in the mice given hyperthermia. A histological study demonstrated the infiltration of neutrophils in the perivascular spaces, indicating an increase of tumor vascular permeability, which might be one of the main reasons for the enhancement of Mab uptake. CONCLUSION: Hyperthermia seems to be a potential method of achieving an increased tumor accumulation of Mab in the radioimmunotargeting of SCLC.

Animals↗