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Biomedical subjects

K Hamamoto

Publications and source records attributed to K Hamamoto.

At least 19 recordsLinked to original sources
PubMed1992

[Intraarterial urokinase infusion therapy with superselective catheterization for acute occlusive cerebrovascular disease].

Intraarterial urokinase infusion therapy with superselective catheterization was performed on 11 patients for acute occlusive cerebrovascular disease. The subjects were five men and six women with a mean age of 70 years (range, 48-83 years). Nine of 11 patients had middle cerebral artery occlusion and two had basilar artery occlusion. The interval from onset to infusion ranged from 3.5 to 9 hours, and the total dosage of urokinase from 24 x 10(4) to 150 x 10(4) IU. Recanalization of the occluded artery was achieved in nine patients (82%), and favorable clinical outcome was achieved in seven patients (64%). Six of whom were discharged with no neurologic deficits. Hemorrhagic infarction occurred in two patients without clinical deterioration. Our observations suggest that intraarterial urokinase infusion therapy with superselective catheterization may be very useful in the acute stage of occlusive cerebrovascular disease.

Acute Disease↗
PubMed1992

[A case with delayed-onset radiation pneumonitis suspected to be induced by oral etoposide].

Radiation pneumonitis usually occurs within 1-3 months after the completion of radiation therapy. A 63-year-old male with primary lung cancer treated by radiation therapy developed radiation pneumonitis 5 months after the completion of radiation therapy. He received 60 Gy to the lung tumor in a conventional fractionation schedule, and then two courses of intravenous chemotherapy using cis-diamine-dichloroplatinum (II) (110-140 mg) and etoposide (140-175 mg). Oral etoposide was initiated for bone metastases on the 104th day after the completion of radiation therapy at a daily dose of 20 mg, to a total dose of 1075 mg. He complained of fever and exertional dyspnea 5 months after the completion of radiation therapy. Chest radiography showed homogeneous infiltrates in the irradiated lung. These clinical signs and symptoms were refractory to antibiotic therapy, but steroid therapy resulted in marked improvement. The development of radiation pneumonitis was suspected to be induced by oral etoposide, which was given before the onset of radiation pneumonitis. These data suggest that etoposide induces a recall phenomenon, as has been demonstrated with such drugs as adriamycin and actinomycin-D.

Administration, Oral↗
PubMed1992

[Temperature distribution and geometry of the electrodes in RF interstitial hyperthermia using circular and interstitial electrodes].

To evaluate the feasibility of clinical application of a newly developed interstitial hyperthermia system, which consists of an 8 MHz radiofrequency generator, interstitial needle electrodes, and a superficial circular electrode, we conducted preclinical experiments using an agar phantom and VX-2 carcinoma in the rabbit. In the experiment with an agar phantom, four 4 cm needle electrodes were placed in a square array at intervals of 1.0, 1.5, and 2.0 cm. Thermography demonstrated homogeneous temperature distribution at electrode intervals of 1.0 and 1.5 cm, but hot spots around the electrodes at an interval of 2.0 cm. When electrode deviation was less than 8 degrees from the parallel plane, no temperature deviation was observed. Using two 2 cm electrodes and two 4 cm electrodes in square array, thermography demonstrated a homogeneous temperature distribution in the area surrounded by the electrodes. Even if the electrodes were located at the periphery of the agar phantom, a homogeneous temperature distribution was obtained in the area surrounded by the electrodes. Using four 4 cm electrodes at intervals of 1.5 cm in VX-2 carcinoma in the rabbit, ideal heating was obtained: 42 degrees C at the periphery of the tumor and 43 degrees C at the center. These data suggest that the newly developed interstitial hyperthermia apparatus provides homogeneous heat distribution at electrode intervals of 1.5 cm or less and can be used in a Phase I study for deep-seated or superficial tumors.

Animals↗
PubMed1992

Effects of injected antibody against the platelet glycoprotein IIb/IIIa complex on monkey platelet fibrinogen.

Four monkeys were injected for a 10-day period with the Fab fragment of a murine monoclonal antibody (NNKY 1-32) which inhibits the binding of fibrinogen to the platelet glycoprotein (GP) IIb/IIIa complex. Platelet fibrinogen levels were assessed quantitatively by electroimmunoassay and qualitatively by immunoelectron microscopy. The platelet fibrinogen level fell to 9.0 +/- 2.8% of the control level after antibody administration. Immunoelectron microscopy showed that the injected antibody was localized on the inner surface of the platelet alpha-granule membrane. Our findings suggest that the GP IIb/IIIa complex can be internalized by alpha-granules and that it may mediate the endocytosis of plasma fibrinogen by platelets.

Animals↗
PubMed1992

[Radiation therapy for patients with obstructive jaundice caused by carcinoma of the extrahepatic biliary system].

From February 1980 through September 1990, 92 patients with obstructive jaundice resulting from biliary tract cancer registered at Shikoku Cancer Center Hospital or Ehime University Hospital. Radiation therapy (RT) was used to treat 38 of these patients (30 with carcinoma of the extrahepatic bile duct, excluding ampulla of Vater, and eight patients with carcinoma of the gallbladder). Of 38 patients, 11 underwent intraoperative radiation therapy (IORT), and 27 were treated by external radiation therapy (ERT) alone. In contrast, 54 patients (39 with carcinoma of the extrahepatic bile duct and eight with carcinoma of the gallbladder) were not treated by RT. All jaundiced patients received external and/or internal biliary drainage of some kind. Among patients undergoing biliary drainage with a catheter, 21 patients who underwent RT (four with IORT) survived significantly longer than 19 patients who did not (generalized Wilcoxon test: p less than 0.05). There were no significant differences in survival between 7 patients with recanalization and 11 patients with no recanalization. Concerning the survival of laparotomized patients, excluding those with complete resection or perioperative death, eight patients treated with postoperative ERT survived longer than 12 patients who did not have postoperative ERT (not significantly). Eleven patients underwent IORT. A patient with unresectable carcinoma of the hilar bile duct survived 2 years and 3 months after a combination treatment of ERT and IOTR. In four of eight autopsied patients, radiation effects of Grade II were observed (Oboshi and Shimosato's evaluation system for the histological effects of radiation therapy). Our experience suggests that RT is effective in patients with obstructive jaundice caused by carcinoma of the biliary system.

Adenocarcinoma↗
PubMed1992

[Results of radiation therapy for squamous cell carcinoma of the uterine cervix using high dose-rate intracavitary irradiation].

We retrospectively analyzed 216 previously untreated patients with cervical cancer treated by high dose-rate intracavitary irradiation between 1978 and 1986. Cumulative 5-year survivals in stage Ib, IIa, IIb, IIIa, IIIb and IVa were 72.3%, 88.9%, 68.9%, 75.0%, 64.0% and 16.7%, respectively. Cause-specific 5-year survivals in stage Ib, IIa, IIb, IIIa, IIIb and IVa were 93.3%, 88.9%, 74.7%, 75.0%, 68.9%, and 18.8%, respectively. Recurrences outside the pelvis in stage IIb and IIIb (14.9% and 24.0%) were more common than loco-regional recurrences (10.3% and 12.0%). However, loco-regional recurrences (50%) were most frequent in stage IVa. Thirteen patients (6.0%) required surgical management for intestinal complications (severe). Six patients (2.7%) died due to intestinal complications (fatal). These fatal and severe complications were closely correlated with the dose of external radiation. These data suggest that intracavitary irradiation using a high dose-rate system is useful for the treatment of uterine cancer; however, further efforts to reduce intestinal complications by lowering the dose of external radiation will be necessary. It is also suggested that a combined modality, such as chemotherapy, is necessary for controlling metastases outside the pelvis in stage IIb and IIIb, and for local control in stage IVa.

Adult↗
PubMed1992

In vitro and in vivo effects of diethylene triamine penta-acetic acid on the distribution of indium-111 monoclonal antibody metabolism.

The effects of diethylene triamine penta-acetic acid (DTPA) on indium-111 monoclonal antibody (MoAb) metabolism were examined. Sequential analysis of 111In-MoAb incubated in serum at 37 degrees C by high performance liquid chromatography (HPLC) and electrophoresis revealed that the radioactivity gradually moved from the MoAb to a 70-90 kDa molecular weight fraction. DTPA inhibited the transchelation of 111In to this fraction. It also decreased 111In uptake by isolated rat hepatocytes but did not remove 111In incorporated in hepatocytes. The daily in vivo administration of DTPA (0.5-2.0 mg/mouse daily) to athymic mice after 111In-MoAb injection significantly reduced the 111In uptake in the liver and kidney. The tumour uptake was decreased somewhat but not significantly. The serum radioactivity in the 70-90 kDa fraction was also decreased. Scintigraphic examination demonstrated a decreased liver uptake in the DTPA-treated group of mice. Our results show that 111In released from the DTPA-MoAb conjugate in serum binds to molecules of 70-90 kDa and that DTPA decreases the 111In uptake in this fraction, which induces a decrease of 111In accumulation in normal tissues.

Animals↗
PubMed1992

Results of the combination of external-beam and high-dose-rate intracavitary irradiation for patients with cervical carcinoma.

We retrospectively analyzed 220 patients with squamous cell carcinoma of the uterine cervix treated by the combination of external-beam and high-dose-rate intracavitary brachytherapy between 1978 and 1986. Five-year survivals for Stage Ib (n = 15), IIa (n = 18), IIb (n = 107), IIIb (n = 50), and IVa (n = 18) were 72.3, 88.9, 68.9, 64.0, and 16.7%, respectively. The incidences of recurrence outside the pelvis in Stage IIb and IIIb patients (15.0 and 24.0%) were higher than those of local recurrences (10.3 and 12.0%). Eighteen patients (8.2% of the total) had serious intestinal complications. These serious complications were closely correlated with the external-beam dosages. External-beam therapy was performed at 1.8-2.0 Gy/day, and high-dose-rate brachytherapy using a remotely controlled afterloading system (RALS) was performed once a week with 6.0-7.5 Gy at points A/fraction. Treatment dosages to the whole pelvis (WP), with central shieldings (CS), and with RALS according to FIGO stage were as follows: Stages Ib, IIa, 30-40 Gy (WP) plus 24-30 Gy (RALS); Stages IIb, IIIb, 40 Gy (WP) plus 10-20 Gy (CS) plus 24-30 Gy (RALS); Stage IVa, 40-50 Gy (WP) plus 10-20 Gy (CS) plus 20-30 Gy (RALS). From these data, the combination of external-beam and high-dose-rate intracavitary irradiation is an effective therapy for cervical cancer. It is also suggested that an additional combined chemotherapy is necessary to control metastic lesions outside the pelvis for Stages IIb and IIIb.

Adult↗
PubMed1992

Acute myelomonocytic leukemia with marrow eosinophilia showing 5q- and 16q22 mosaicism.

We report an 82-year-old Japanese female with acute myelomonocytic leukemia with dysplastic marrow eosinophilia (FAB M4Eo) exhibiting a partial deletion of the long arm of chromosome 5, del(5)(q13q31) and a derivative chromosome 16 with a breakpoint at band 16q22, in addition to 5q-. The patient had a history of a preleukemic phase for several months with marked dysplasia in trilineage marrow cells, in addition to leukemic features compatible with M4Eo. These findings strongly suggested that the leukemic cells in this case were derived from a preleukemic clone with a del(5q).

Aged↗
PubMed1992

Electron beam intraoperative radiation therapy (EBIORT) for localized pancreatic carcinoma.

Treatment results for 37 patients with localized pancreatic carcinoma treated using electron beam intraoperative radiation therapy (EBIORT) with curative intent from 1978 to 1990 in National Shikoku Cancer Center Hospital and the related hospitals were presented in comparison with those of a control group comprising 40 patients treated with no use of EBIORT. With additional treatment of EBIORT, 37 patients survived longer than the control 40 patients (p less than 0.05 during the 19th and 31st month). In the macroscopically total or partial resection, patients treated with EBIORT survived slightly longer than the controls. In the unresectable lesions, patients treated with EBIORT survived longer than the control patients (p less than 0.05 during the 7th month). In this group, there was one 5-year survivor who received EBIORT plus postoperative external radiation therapy (ERT) to the unresectable pancreatic head lesion but died 5 years later of massive bleeding from the duodenal ulcerations. Patients with unresectable carcinoma treated by EBIORT plus ERT survived longer than patients treated with EBIORT alone (p = 0.065). Pain relief was obtained in 95.0% of the unresectable patients with pain. Major adverse effects caused by irradiation were gastrointestinal troubles in five patients (leakage of choledochojejunostomy, gastric ulcerations, duodenal stenosis, gastric ulcerations and duodenal stenosis, duodenal perforation and ulcerations). EBIORT proved to be effective in the relief of serious pain and in the improvement of the survival of patients with localized pancreatic carcinoma.

Adult↗
PubMed1992

Patterns of failure and survival in locally advanced carcinoma of the uterine cervix treated with high dose-rate intracavitary irradiation system.

We retrospectively analyzed 71 patients with locally advanced carcinoma of the uterine cervix treated by irradiation using high dose-rate intracavitary brachytherapy between 1978 and 1985. Seven patients were Stage IIIa, 46 Stage IIIb, and 18 Stage IVa. Five-year survivals for Stage IIIa, IIIb, and IVa were 71.4, 60.9, and 16.7%, respectively. An analysis of patterns of failure demonstrated that loco-regional recurrences were observed in 1 (14.3%) for Stage IIIa, 6 (13.0%) for Stage IIIb, and 9 (50.0%) for Stage IVa. The incidence of recurrence outside the pelvis observed in Stage IIIb patients (7 para-aortic nodes, 5 distant metastases) was much higher than that of local recurrence. Five patients (7.0% of the total: 1 with Stage IIIa, 3 with Stage IIIb, 1 with Stage IVa) required surgery to manage the complications. These data suggest that a high dose-rate intracavitary irradiation system is an effective tool for the treatment of cervical cancer. Further efforts to control metastatic lesions outside the pelvis are required for patients with Stage IIIb. To increase a loco-regional control rate for patients with Stage IVa disease, it is important to give additional treatment such as chemotherapy in conjunction with radiation therapy.

Adult↗
PubMed1992

Effect of long-term calcitonin therapy by injection and nasal spray on the incidence of fractures in osteogenesis imperfecta.

The effect of calcitonin therapy by injection or nasal spray on the incidence of bone fractures was studied in patients with osteogenesis imperfecta. In contrast to injection of calcitonin, intranasal administration of calcitonin twice a week for 2 weeks, followed by 2 weeks of no therapy, was simple and seemed beneficial for decreasing bone fractures in patients with osteogenesis imperfecta.

Administration, Intranasal↗
PubMed1992

Ga-67 citrate scintigraphy for the early detection of radiation pneumonitis.

To evaluate the usefulness of Ga-67 citrate scintigraphy in the early detection of radiation pneumonitis, scintigrams from 103 patients who were treated with radiation therapy for lung cancer were retrospectively analyzed with regard to abnormal Ga-67 uptake after radiation therapy in sites other than the original or recurrent tumors. Sixteen (20%) of the 80 asymptomatic cases showed positive Ga-67 scintigrams. All of the other 23 symptomatic cases showed positive Ga-67 scintigrams. Thirteen (57%) of these 23 cases had negative chest radiographs although their Ga-67 scintigrams were positive. Detection of radiation pneumonitis by Ga-67 scintigraphy was significantly earlier than that possible by chest radiography (P less than 0.01). These data suggest that Ga-67 scintigraphy is more useful and sensitive than chest radiography for the early detection of radiation pneumonitis.

Aged↗
PubMed1992

[Steroid and gamma globulin therapy against virus-associated hemophagocytic syndrome].

A 21-year-old woman was admitted to our hospital because of high fever, cough, and headache. Other clinical manifestations included hepatosplenomegaly, anemia, leukopenia, and mild liver dysfunction. As she had been diagnosed to have systemic lupus erythematosus (SLE) previously, we first suspected that this disease had become exacerbated. However, the titers of anti-EB virus (VCA-IgG) and some other viruses were high on admission, and hemophagocytosis by macrophages was observed on bone marrow examination. Therefore, she was diagnosed to have virus-associated hemophagocytic syndrome (VAHS). Prednisolone therapy was then initiated, but the patient responded poorly. We next tried gamma globulin, and the clinical findings and laboratory data were improved. Our patient showed a very favourable clinical course following gamma globulin therapy, suggesting that steroid and gamma globulin should be considered as a treatment even in the early stages of this syndrome in adults.

Adult↗
PubMed1992

[Potential application of DTPA for improving the image quality in radioimmunoscintigraphy with 111In labeled monoclonal antibodies].

Studies on application of diethylenetriamine-pentaacetic acid (DTPA) to decrease the non-specific localization of 111In-labeled antibodies (111In-MoAb) to the liver were performed. The transchelation of 111In to the molecule of M.W. 70,000-90,000 by the incubation of 111In-MoAb in human serum was inhibited by adding DTPA. These in vitro findings were also demonstrated by serum analysis after 111In-MoAb injection to the normal mice and postinjection of DTPA. By addition of DTPA, the uptake of 111In-MoAb by isolated rat hepatocytes was inhibited, but the 111In-release was unaffected. The addition of DTPA had no effect on uptake of 111In-MoAb and 111In-release in tumor cells. These results suggest that DTPA administration following 111In-MoAb injection may inhibit transchelation of 111In to transferrin or other serum proteins, so decrease non-specific liver localization of 111In and give rapid blood clearance.

Animals↗
PubMed1992

Kinetic behavior of technetium-99m-HMPAO in the human brain and quantification of cerebral blood flow using dynamic SPECT.

The kinetic behavior of 99mTc-hexamethylpropyleneamine oxime (HMPAO) in the human brain was investigated in 11 patients with various brain diseases (176 regions), using dynamic SPECT and a four-compartment model with five parameters (K1: rate constant for the transport of HMPAO from blood to brain, K2: backdiffusion from brain to blood, K3: conversion to a hydrophilic form in the brain, K5: conversion to a nondiffusible form in the blood, and fa: fraction of radioactivity attributable to the vascular compartment). Although K1 correlated well with cerebral blood flow (CBF) measured by the 133Xe inhalation method (Xe-CBF) (r = 0.888), its value was underestimated by 28.9% +/- 11.9%, indicating a low extraction fraction (E) for HMPAO. From E = K1/CBF, a regression equation of E = 0.857 - 0.00335. Xe-CBF was obtained. Significant correlations were observed for K2 versus Xe-CBF (r = 0.679), for K3 versus Xe-CBF (r = 0.483), for K3/(K2 + K3) versus Xe-CBF (r = -0.487), for K3/K2 versus Xe-CBF (r = -0.501), and for K2 + K3 versus Xe-CBF (r = 0.655), but not for K1/K2 versus Xe-CBF (r = 0.005). Thus, this model was useful for elucidating the kinetic behavior of HMPAO in the human brain, and correction for E appears to be indispensable for accurate CBF quantification using HMPAO.

Adult↗
PubMed1991

[Embolotherapy of varicocele by stainless steel coil].

Fifty-two patients with varicocele underwent embolotherapy using stainless steel coils. Forty-six of the patients complained of infertility, four of scrotal mass and two of scrotal pain. The procedure was successful in 42 of the 52 patients (81%). Positive semen analyses increased 53% (16/30), and the number of subsequent pregnancies was five of 33 (15%). We conclude that embolotherapy with the coils is a useful therapeutic procedure for varicoceles.

Adolescent↗