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Biomedical subjects

O Nakamura

Publications and source records attributed to O Nakamura.

At least 91 records · Page 5Linked to original sources
PubMed1989

[Surgical treatment on survival and quality of life in patients with supratentorial glioblastoma:].

One hundred one patients with glioblastoma were studied to evaluate the effect of the extent of surgical resection on the length and quality of life. Extensive removal of tumor was performed for 45 patients, while the remaining 56 patients underwent partial removal or biopsy of tumor. The median time to tumor progression and the median survival in the former patients were 18.0 months and 23.0 months, respectively, and, in the latter patients, 6.0 months and 10.0 months, respectively. More than 80% of Karnofsky rating was observed in 69% of the former patients. Extensive removal of glioblastoma would be associated with longer and better survival when compared to partial removal.

Adult↗
PubMed1988

A monoclonal antibody against dentin phosphophoryn recognizes a bone protein(s) appearing at the beginning of ossification.

Decalcified and nondecalcified sections of fetal bovine tibia were stained immunohistochemically with a monoclonal antibody against dentin phosphophoryn. In the epiphyseal portion of the long bone, osteoblasts, osteocytes and the bone matrix were stained, but chondrocytes and the cartilage matrix were not. Similar staining was observed in the epiphyseal and diaphyseal portions of bones. These findings suggest that a protein(s) with the same epitope as phosphophoryn may be synthesized and secreted by osteoblasts at the beginning of ossification and may be involved in mineralization of bone tissue. On Western blots of proteins extracted from fetal bovine bone, the antibody reacted with two bands of molecular weights of about 71,000 and 63,000. These proteins and antibody(s) to the proteins may be useful for detection of the phenotype of osteogenesis.

Animals↗
PubMed1988

[Response to antitumor agents of human transplantable glioma implanted into chorioallantoic membrane of chick embryo].

In case of chemotherapy against brain tumors, it is most important to choose suitable drugs for brain tumors, since human tumors have different drug sensitivity and growth. Heretofore, the nitrosourea-induced rat glioma cell, such as C6, or immunodeficient mice were usually used for predicting the drug sensitivity of brain tumors. We took notice of Murphy's system for the chemosensitivity test, in which a human tumor is transplanted into the chorioallantoic membrane (CAM) of a chick embryo. By modifying the conventional Murphy's system, we studied the efficiency of this system in predicting the drug sensitivity of brain tumors. First, we compared the result of a drug sensitivity test using CAM of a chick embryo with that using nude mice. Next we studied the effect of chemotherapeutic agents against brain metastasis of a chick embryo caused by the intravenous injection of mouse B16 melanoma cells. The tumor reduction rate of the sensitivity test using a chick embryo tended to agree with that using nude mice. In the drug sensitivity test against brain metastasis, ACNU was the most effective. This result supports the result of the clinical study. In conclusion, the drug sensitivity test using a chick embryo is thought to be useful and the advantages or disadvantages of this system are discussed.

Allantois↗
PubMed1988

[Antineoplastic effect of prostaglandins on human glioma in athymic nude mice].

The prostaglandins (PG) are known to have various physiological effects. Some series of prostaglandins such as PG D2 have been reported to inhibit growth of tumor cells. In this study, the growth-inhibitory effects of PG A2, PG D2, PG J2 and 6-keto PGE1 were investigated in nude mice receiving subcutaneous transplant of human brain tumor. One to two milligram of prostaglandins was given intraperitoneally every day for three weeks. Tumor volumes were measured twice weekly and the tumor reduction rates (treated/control) were evaluated. T/C rate treated with PG D2 or PG A2 was 50-60% respectively. The effectiveness of PG J2 or 6-keto PGE1 was inferior to that of PG A2 or PG D2. But in the evaluation of antitumor effects of PG J2, we must consider the fact that the activity of PG J2, is liable to be lost. The effect of PG D2 on proliferation of cultured glioma cells was also studied. At concentrations of 10 micrograms/ml, PG D2 strongly inhibited the proliferation of glioma cells. However, precise mechanism of prostaglandin action is presently unknown. Further studies are required to clarify the mechanism of antitumor effects of prostaglandins.

Alprostadil↗
PubMed1988

[Chemosensitivity test for human gliomas].

In case of chemotherapy against brain tumors, it is most important to choose suitable drugs for brain tumors, since human tumors have different drug sensitivity and growth. Heretofore, human tumor clonogenic assays or human glioma-bearing nude mice models were usually used for predicting the drug sensitivity of brain tumor. Human tumor clonogenic assays are one of the best in vitro tests for anticancer drug activity. However, plating efficiency is low, sometimes preventing evaluation of drug sensitivity, and the slow growth of colonies means that culture time is long. Assays using immunodeficient mice are used for predicting the drug sensitivity of human tumors; usually results reflect the sensitivity of the parent tumor. However, procedure using athymic nude mice are slow and expensive. We took notice of Murphy's system for the chemosensitivity test, in which a human tumor is transplanted into the chorioallantoic membrane (CAM) of a chick embryo, because in this system, various kinds of human tumors could be grafted in high rate. By modifying the conventional Murphy's system, we studied the efficiency of this system in predicting the drug sensitivity of brain tumors. We compared the result of a drug sensitivity test using CAM of a chick embryo with that using nude mice. First, we studied the effect of chemotherapeutic agents such as ACNU, bleomycin. Next, we studied the effect of combination treatment of CAP or CAPF. The tumor reduction rate of the sensitivity test using a chick embryo tended to agree with that using nude mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

[Brain necrosis following intraoperative radiation therapy or interstitial brachytherapy].

We have experienced 8 cases of radiation necrosis which occurred following radiation therapy of malignant brain tumors. In all 8 cases, necrosis developed in the brain tissue adjacent to the tumor after intraoperative radiation or interstitial radiation therapy. Considering that the extent of necrosis usually coincides with the extent of the radiation therapy, this type of necrosis is thought to be the expected result of radiation therapy. A differential diagnosis between radiation necrosis and the recurrence of a brain tumor has been thought to be difficult to achieve. Yet with the use of a dynamic CT or an Xe-enhanced CT, differential diagnosis between these two lesions was clearly accomplished.

Adult↗
PubMed1988

[Decreased tumor viability of gliomas after radiation therapy, evaluated by dynamic CT scan].

The tumor viability of 28 gliomas after radiation therapy has been investigated by dynamic CT scan that estimated 4 parameters (Area, Peak, Time of Peak, and, Height of Plateau) from a time-density curve. Glioblastoma showed higher values of Area and Peak, whereas astrocytomas showed lower values when compared to those found in normal gray matter. After radiation therapy, the Area and Peak decreased and the Time to Peak was prolonged, suggesting a decrease in blood volume and blood flow in the tumor tissue. The increased Height of Plateau showed an increased permeability of the tumor-vessels. These results suggest that a dynamic CT scan provides a useful indicator of the change in tumor-viability after radiation therapy.

Adult↗
PubMed1988

[Angioblastic meningioma with metastases to the vertebra and adjacent bones: a case report].

A case of angioblastic meningioma with multiple metastases to the vertebra and the adjacent bones is presented. A 60-year-old man was admitted to our hospital complaining of pain in the left arm, right chest and abdominal wall, the left buttock, and on the posterior surface of the both legs. He had first undergone subtotal removal of tentorial meningioma eight years before admission. Histological diagnosis of angioblastic meningioma was confirmed. He subsequently received radiation therapy when the tumor recurred six years before admission and again underwent subtotal removal of the recurrent tumor, followed by radiation therapy, four years before admission. Bone scintigrams demonstrated abnormal uptake of radionuclide by the vertebral arches of Th 1, Th 10, Th 11, the vertebral bodies of L 4, L 5, the right 7th rib, and the left iliac bone. Myelography and CT examination with intrathecal infusion of metrizamide revealed marked cord-compression by the space-occupying lesions at the level of the first and the tenth thoracic vertebral bodies. Chest roentgenograms, ultrasonograms and whole body CT examinations showed no other lesions. The tumor was partially resected from the iliac lesion. The diagnosis of metastatic meningioma was confirmed by the histological findings. Postoperative radiation therapy to the first, tenth, and eleventh portions of the thoracic vertebra, and the fourth and the fifth portions of the lumbar vertebra--the causative lesions of the pain--relieved the pain.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Neoplasms↗
PubMed1987

rCBF in brain tumours as measured by xenon enhanced CT.

Heretofore, the rCBF of brain tumours has been measured by the 133Xe clearance method, but the resolving power of this method is limited and flow values measured by this method correlate poorly with the anatomical structure. On the other hand, our xenon-enhanced method has several advantages over the conventional isotope method and enables us to evaluate rCBF with a resolving power of 4 mm. With this method, we evaluated rCBF in 15 brain tumour cases and obtained the following results: Mean rCBF value of the tumour is a little lower than that of grey matter and higher than that of white matter with oedematous change. The xenon-enhanced method enables us to distinguish the demarcation between the tumour area and the surrounding oedematous area and offers useful information for determining the extent of resection in surgery. Mean lambda value of the tumour which is not obtainable in vivo by radionuclide scanning, was 1.02 +/- 0.06 for gliomas and 0.72 +/- 0.09 for metastatic tumours.

Adult↗
PubMed1987

[Application of flow cytometry to the chemosensitivity test by the BrdU labeling method; a preliminary report].

In the present paper we discussed whether a new method of chemosensitivity test could be developed using FCM (flow cytometry) and applied to malignant brain tumor cells labelled with BrdU monoclonal antibody. For this purpose, a basic study was performed with an ACNU-resistant C6 cell line and a sensitive one to see if this method was able to detect the difference of sensitivity between these cell lines. After 8 hours treatment with ACNU (concentration: 10 micrograms/ml), ACNU-sensitive cells revealed on LI (labeling index) of 46%, which was very high in comparison with controls, whereas the figure for ACNU-resistant cells was 34%, which was almost the same LI value as non-treated control cells. This means that change in the BrdU labeling index after chemotherapy in vitro can be used to determine the chemosensitivity of malignant brain tumors when FCM is employed. Furthermore, this method can detect the chemosensitivity of each clone in polyclonal human tumors which is impossible for the HCSA method, since the latter can reveal only the chemosensitivity as a whole in such tumors.

Antibodies, Monoclonal↗
PubMed1987

[Treatment of autochthonous rat brain tumors with chemotherapy and radiotherapy].

The authors tried to establish a model of primary, autochthonous avian sarcoma virus-induced rat glioma for experimental chemotherapy and radiotherapy. It was found that the intracerebral inoculation of 2 X 10(6) FFU/5 microliter of an infectious cells-free homogeneous sub-group D Schmidt-Ruppin avian sarcoma virus into 3-day-old inbred Fischer rats induced brain tumors in all rats. The mean survival time of the inoculated rats was 58.7 +/- 12 days. With regard to the classification of the induced brain tumors in Fischer rats, astrocytoma accounted for 70%. This ASV-induced tumor in rats fulfills the following criteria for a desirable animal model. Spontaneously arising. Glial origin. Intraparenchymal growth. Uniformly fatal within a reasonable time period. In the present study, the therapeutic effects of anticancer drugs, such as ACNU and vincristine were evaluated and additionally, the effect of ACNU used in conjunction with radiation was also evaluated in this model. The mean survival time of rats was prolonged significantly with ACNU (20 mg/kg) or radiation therapy (1,000 rads), respectively, and in cases where ACNU was used together with radiation, the mean survival time was prolonged further still, but not very significantly, in comparison with radiation therapy alone. In conclusion, the ASV-induced rat glioma model was considered to be closely akin to a spontaneous brain tumor in terms of morphology, blood supply and kinetics of the primary tumor. Moreover, the therapeutic sensitivity of this model to anticancer drugs was fairly similar to that of human anaplastic astrocytoma. Considering these observations, this model seems to be an excellent experimental brain tumor model which is useful for evaluating the effect of new therapies against malignant brain tumors.

Animals↗
PubMed1987

[Lipid composition of human malignant brain tumors].

Malignant transformation is characterized by the uncontrolled proliferation of cells. And changes in the composition of glycolipids, cell surface component which may be involved in regulation of cell growth, were often observed in the malignant transformation. In this study, cholesterol, lipid-bound phosphorus, cerebroside, sulfatide and ganglioside were quantitated in the tissue of 20 human malignant brain tumors (malignant glioma, 8; low grade glioma, 4; metastatic tumor, 7; malignant meningioma, 1). As compared with normal brain, all tumor tissue contained lower cholesterol, sialic acid, cerebroside and sulfatide. Metastatic brain tumor or glioma showed characteristic patterns in the content of ganglioside, cerebroside and sulfatide respectively. The ganglioside patterns of metastatic tumor or glioma contained a greater proportion of structurally simpler gangliosides than normal brain. And in metastatic tumor, GM3 was a major ganglioside. On the contrary, glioma had increased proportion of GM3 and GD3 gangliosides. High grade glioma such as Grade 3-4 contained higher proportion of GM3 and GD3, whereas low grade glioma (Grade 1-2) contained less proportion of GM3 and GD3.

Brain Neoplasms↗
PubMed1987

[Antineoplastic effect of beta-IFN and gamma-IFN on malignant gliomas].

We have compared the anti-tumor effects of beta- and gamma-interferons (IFN) against human glioma cells using in vitro model, flow cytometry and xenograft in nude mouse. Contrary to gamma-IFN which had a negligible effect on the growth of glioma cells, beta-IFN showed a dose dependent growth-inhibitory effect on glioma cells in vitro. Our flow cytometry studies revealed that proportion of DNA contents which represent the S and/or G2M phase of cell cycle was markedly increased in cells treated with beta-IFN. However, in cells treated with gamma-IFN, no perturbations in cell cycle distribution were observed. Regarding the anti-tumor effect examined using xenograft of human glioma cells in nude mouse, the tumor reduction rate which was calculated from the ratio of tumor volume between treated (T) and control (C) groups and expressed as T/C value, was 0.44 in animals treated with beta-IFN. However, T/C value in animals treated with gamma-IFN was 0.80 which was derived from the weaker anti-tumor effect of gamma-IFN as compared with that of beta-IFN. Beta-IFN was found to cause a partial suppression of the growth of glioma strain used in this study which confirms our previous report that beta-IFN is effective in reducing tumor size in 2 of 6 glioma strains tested. On the other hand the anti-tumor effect of gamma-IFN, at least in terms of direct effect, against glioma cells used in this study was minimum. However, the mechanism of gamma-IFN's anti-tumor effect may exert mainly through the potentiation of immuno-defence mechanism and the further studies on its pharmacodynamics will be necessary to evaluate the anti-tumor effect of gamma-IFN.

Animals↗
PubMed1987

[Regional cerebral blood flow in brain tumors analyzed by N-isopropyl-(123I)-p-iodoamphetamine (IMP)].

N-Isopropyl-(123I)-p-Iodoamphetamine (IMP), a newly developed tracer for regional cerebral blood flow, was applied to 18 patients with brain tumors. The static scan images were obtained by a single photon emission CT 20 minutes after IMP injection, and revealed decreased IMP uptake in the tumor region in 17 out of 18 patients. This result suggests the lack of an IMP-trapping mechanism in the tumor. In dynamic scan images, which were taken every 2 minutes just after IMP injection, IMP uptake in the tumor was intermediate between that of contralateral white matter and gray matter, and it increased momentarily in accordance with that of the gray and white matter. This finding indicates that the IMP uptake in a dynamic scan would express the regional tissue blood flow in the tumor.

Aged↗
PubMed1987

[Surgery of metastatic brain tumors with new surgical instruments].

The risk of damages of neurological function by the operation of metastatic brain tumors was reduced considerably after introduction of neurosurgical apparatuses, such as ultrasonograph, ultrasonic surgical aspirator and laser scalpel. Of these, ultrasonograph is useful to indicate the exact location of brain tumor at real time during the operation. Ultrasonic surgical aspirator reduced the risk of damage on important brain structures due to the selectivity of fragmentation and the safety of the dissection in the vicinity of important vessels and nerve tissues. Laser scalpel is also useful to extirpate the hemorrhagic tumor with hard consistency. Cases introduced in this paper were: case 1, brain metastasis from lung cancer located just under the left motor area in brain; case 2, metastasis with abundant neovascularization from renal cancer to orbital cavity which showed invasion to orbital roof and frontal bone; case 3, radiation induced sarcoma after the treatment of retinoblastoma; case 4, a large cerebellar metastatic tumor; case 5, neurogenic sarcoma which were successfully removed by using one of or combination of ultrasonograph, ultrasonic aspirator and laser scalpel. Advantage of these new instruments for the surgery on metastatic brain tumor was mentioned here. However, it is necessarily to get a custom before we use these apparatuses at operation efficiently.

Adult↗
PubMed1987

[The treatment of brain metastasis from lung cancer].

From August, 1976, through May, 1986, 111 patients with brain metastasis from lung cancer received various treatments according to their systemic conditions. Forty-two out of 55 patients without systemic metastasis were selected for surgical removal followed by radiation therapy, and the remaining 13 inoperable patients received radiation therapy alone. The median survival of the former group was 14.5 months with a 1-year survival rate of 57.2%, and was 11.0 months with a 1-year survival rate of 38.1% for the latter group. Twenty patients among the former group received intraoperative radiation therapy, and the result obtained was the same as that of the remaining 22 patients treated by surgery and conventional external radiation therapy. As to the conservative therapy applied for the 47 cases with systemic metastasis, radiation therapy, surgical decompression or steroid therapy were planned. The overall median survival of patients of this group was 3.5 months, with a 6-month survival rate of 27.7%. Radiation therapy combined with cisplatin was evaluated to be effective, showing more than 50% reduction of tumor volume in 73.9% of patients. The surgical removal of metastatic tumors should be considered for patients without systemic metastasis, and should also be followed by radiation therapy. Such cases would be expected to survive for more than 1 year, whereas there is no suitable treatment for patients with systemic metastasis.

Brain↗