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H Tsujii

Publications and source records attributed to H Tsujii.

At least 19 recordsLinked to original sources
PubMed2001

Overexpression of mitochondrial manganese superoxide dismutase protects against radiation-induced cell death in the human hepatocellular carcinoma cell line HLE.

We investigated the potential role of mitochondrial manganese superoxide dismutase (Mn-SOD) in protective activity against irradiation by analyzing cell viability by a colony formation assay and by detecting apoptosis in stably human Mn-SOD gene-transfected HLE, a hepatocellular carcinoma cell line. We found that overexpression of Mn-SOD reduced the levels of reactive oxygen species in the mitochondria and intracellular phospholipid peroxidation product (4-hydroxy-2-nonenal) and prevented cell death. The production of intracellular nitric oxide after irradiation was not changed by Mn-SOD overexpression. The results suggested that Mn-SOD might play an important role in protecting cells against radiation-induced cell death by controlling the generation of mitochondrial reactive oxygen species and intracellular lipid peroxidation.

Apoptosis↗
PubMed2001

High linear energy transfer carbon radiation effectively kills cultured glioma cells with either mutant or wild-type p53.

PURPOSE: A mutation in the p53 gene is believed to play an important role in the radioresistance of many cancer cell lines. We studied cytotoxic effects of high linear energy transfer (LET) carbon beams on glioma cell lines with either mutant or wild-type p53. METHODS AND MATERIALS: Cell lines U-87 and U-138 expressing wild-type p53 and U-251 and U-373 expressing mutant p53 were used. These cells were irradiated with 290 MeV/u carbon beams generated by the Heavy Ion Medical Accelerator in the National Institute of Radiologic Science or X-rays. A standard colony-forming assay and flow cytometric detection of apoptosis were performed. Cell cycle progression and the expression of p53, p21, and bax proteins were examined. RESULTS: High LET carbon radiation was more cytotoxic than low LET X-ray treatment against glioma cells. The effects of the carbon beams were not dependent on the p53 gene status but were reduced by G(1) arrest, which was independent of p21 expression. The expression of bax remained unchanged in all four cell lines. CONCLUSION: These results indicate that high LET charged particle radiation can induce cell death in glioma cells more effectively than X-rays and that cell death other than p53-dependent apoptosis may participate in the cytotoxicity of heavy charged particles. Thus, it might prove to be an effective alternative radiotherapy for patients with gliomas harboring mutated p53 gene.

Apoptosis↗
PubMed2001

Recurrent hepatocellular carcinoma versus radiation-induced hepatic injury: differential diagnosis with MR imaging.

The objective of this study was to assess the value of MR imaging in the differentiation between a recurrent hepatocellular carcinoma (HCC) and a radiation-induced hepatic injury. Nine male patients with suspected recurrence after radiotherapy for HCC underwent T(2)-, T(1)-weighted imaging and Gd-DTPA enhanced dynamic studies. T(2) relaxation times, signal intensity ratios in T(1)-weighted images (WI) and the relative enhancement of the dynamic study were calculated. Recurrent tumors and the irradiated area showed similar image characteristics: hypointense in T(1)-WI and hyperintense in T(2)-WI. T(2) values and signal intensity ratios in the T(1)-WI were not significantly different. In the gadolinium-enhanced dynamic study, a recurrent HCC showed early enhancement, followed by a rapid washout. However, the irradiated liver parenchyma showed hyperintensity from an early phase, and contrast enhancement tended to be more prominent and prolonged at the end of the dynamic studies. The characteristic findings of the dynamic MR study enable us to distinguish between a recurrent HCC and a radiation-induced hepatic injury.

Aged↗
PubMed2001

Effects of dopamine d2 receptor agonists in a pituitary transplantation-induced hyperprolactinaemia/anovulation model in rats.

1. In the present study, we investigated the effects of hyperprolactinaemia, induced by transplantation of anterior pituitary glands under the kidney capsule in female rats, on the relationship between serum and pituitary concentrations of the gonadotropins and on the oestrous cycle. 2. Rats with pituitary transplants showed increased serum prolactin concentrations and decreased serum concentrations of gonadotropins and increased pituitary concentrations of gonadotropins. Moreover, these rats showed persistent dioestrous and anovulation from 3 to 6 days after transplantation. 3. A single oral administration of cabergoline (at doses between 0.001 and 0.1 mg/kg) dose-dependently inhibited the elevated serum prolactin concentrations in hyperprolactinaemic rats. At 0.1 mg/kg, cabergoline induced a continuous reduction in serum prolactin concentrations for 5 days after administration. Terguride (0.1 mg/kg) and bromocriptine (10 mg/kg) also reduced serum prolactin concentrations at 1 and 3 days after administration. All three dopamine D2 receptor agonists increased serum gonadotropin concentrations and ovarian weight at 3 days after administration. 4. In rats exhibiting anovulation, a single oral administration of any one of the three dopamine D2 receptor agonists dose-dependently restored ovulation and a normal oestrous cycle appeared. Oral administration of cabergoline (0.03 mg/kg) or terguride (0.1 mg/kg) restored ovarian function and abolished the anovulation following a reduction in serum prolactin concentrations. However, bromocriptine (10 mg/kg) did not completely abolish anovulation. Following administration of terguride (0.3 mg/kg) or bromocriptine (30 mg/kg), only one normal oestrous cycle appeared; however, following cabergoline (0.1 mg/kg), two normal oestrous cycles appeared. 5. These results suggest that cabergoline has a potent and long-lasting action as a dopamine D2 receptor agonist and, thus, should be a useful drug for the treatment of galactorrhoea and hyperprolactinaemic amenorrhoea and/or anovulation in humans.

Animals↗
PubMed2001

Combined trisomy 9P and Shprintzen syndrome resulting from a paternal t(9;22).

The authors report on a female infant with partial trisomy 9 (pter-->q12) together with partial monosomy 22 (pter-->q11.23) that included DiGeorge critical region (DGCR), as a result of adjacent-2 disjunction. In addition to the clinical features characteristic of trisomy 9p syndrome, the patient had Truncus arteriosus type A2, bilateral hydronephrosis, palatal anomaly, retrognathia, and laryngeal hypotonia, which are likely to be attributed to 22q11.2 deletion. This patient appears to be the first reported case with such unbalanced translocation resulting from a paternal reciprocal translocation. For live birth, the risk for male carrier is 8.7-17.4%. It is important to consider this higher risk when counseling. Precise study concerning the presence of the DGCR can facilitate in the better understanding of the condition.

Abnormalities, Multiple↗
PubMed2000

Progesterone receptor is a favorable prognostic factor of radiation therapy for adenocarcinoma of the uterine cervix.

PURPOSE: The prognostic significance of the expression of estrogen receptors (ER) and progesterone receptors (PgR) in adenocarcinoma of the uterine cervix has been controversial. Hence, the relationship between the expression of the hormone receptors and clinical outcome was evaluated for patients with adenocarcinoma treated with radiation therapy alone. MATERIALS AND METHODS: This study involved 66 patients with cervical adenocarcinoma consisting of 44 adenocarcinomas and 22 adeno-squamous cell carcinomas. They received radiation therapy at the National Institute of Radiological Sciences Hospital between 1962 and 1993. The mean age of the patients was 62. 0 +/- 12.0 years (range, 36-82 years). The numbers of patients with Stage I, II, III, and IV diseases were 7, 17, 27, and 15, respectively. Their ER and PgR statuses were investigated immunohistochemically using biopsy specimens excised from the cervical tumors before radiation therapy. RESULTS: ER staining was positive in 12 patients (19%). ER status did not correlate with the 5-year cause-specific, local-control, and disease-free survivals. PgR staining was positive in 12 patients (19%). The disease-free survival rate of PgR-positive patients was significantly higher than that of PgR-negative patients (p = 0.044). Although PgR status did not reach statistical significance in relation to the 5-year cause-specific survival and local-control survival, the better survival was due to less local recurrence rather than to less distant metastasis. CONCLUSION: The present study suggested that PgR status was associated with prognosis after radiation therapy for adenocarcinoma of the uterine cervix.

Adenocarcinoma↗
PubMed2000

Magnetic order in the heavy fermion compound CeCu6 at mK temperatures

We have measured the ac magnetic susceptibility in various fields and thermal expansion of single crystals of the heavy fermion compound CeCu6 at temperatures down to 250 &mgr;K. The susceptibility of CeCu6 shows a peak at about 2 mK and has a large anisotropy. We also detected an anomaly of thermal expansion at the same temperature. The observed behaviors of the susceptibility and the thermal expansion in CeCu6 indicate the occurrence of an antiferromagnetic order.

Journal Article↗
PubMed2000

X-rays vs. carbon-ion tumor therapy: cytogenetic damage in lymphocytes.

PURPOSE: To measure chromosomal aberrations in peripheral blood lymphocytes from cancer patients treated with X-rays or carbon ions (C-ions). METHODS AND MATERIALS: Blood samples from patients diagnosed for esophageal or uterine cervical cancer were obtained before, during, and at the end of the radiation treatment. The novel technique of interphase chromosome painting was used to detect aberrations in prematurely condensed chromosomes 2 and 4. The fraction of aberrant lymphocytes was measured as a function of the dose to the tumor volume. For comparison, blood samples were also exposed in vitro to X-rays or to carbon ions accelerated at the HIMAC. RESULTS: C-ions were more efficient than X-rays in the induction of chromosomal aberrations in vitro. In patients with similar pathologies, tumor positions, and radiation field sizes, however, C-ions induced a lower fraction of aberrant lymphocytes than X-rays during the treatment. The initial slope of the dose-response curve for the induction of chromosomal aberrations during the treatment was correlated to the relative decrease in the number of white blood cells and lymphocytes during the treatment. CONCLUSION: C-ions induce a lower level of cytogenetic damage in lymphocytes than X-rays, reducing the risk of bone marrow morbidity.

Aged↗
PubMed2000

Complex-type chromosomal exchanges in blood lymphocytes during radiation therapy correlate with acute toxicity.

The new method of chemical-induced premature chromosome condensation combined with fluorescence in situ hybridization was used to analyze chromosomal damage in peripheral blood mononuclear lymphocytes of patients undergoing radiation treatment for esophageal cancer with high-energy X-rays or accelerated carbon ions at the National Institute of Radiological Sciences (Chiba, Japan). Total number of aberrant cells correlated with radiation field size, but no correlation was found with acute toxicity. A high frequency of complex-type exchanges were also recorded. This aberration type presented a high individual variability, and correlated well with the acute morbidity. Cytogenetic analysis by interphase chromosome painting is proposed as a useful tool for monitoring normal tissue effects during radiotherapy.

Aged↗
PubMed2000

Serum CYFRA 21-1 in cervical cancer patients treated with radiation therapy.

BACKGROUND: A fragment of cytokeratin 19, referred to as CYFRA 21-1, is abundant in the serum of many patients with malignant tumors and is recognized as one of the established tumor markers, especially for non-small-cell lung cancer. In this study, the clinical usefulness of CYFRA 21-1 was investigated in cervical cancer patients treated with radiation therapy with reference to squamous-cell-carcinoma-related antigen (SCC-Ag), a common tumor marker of cervical squamous cell carcinoma. MATERIALS AND METHODS: The serum levels of CYFRA 21-1 and SCC-Ag of 50 patients with squamous cell carcinoma of the uterine cervix were measured before and after radiation therapy. RESULTS: CYFRA 21-1 was positive in 52% of the patients. The incidence increased with the stage of the cancer, and post-treatment increases were a sign of disease progression. During radiation, serum levels of CYFRA 21-1 decreased significantly and reflected the radiation effect well. In addition, CYFRA 21-1 was negative in all patients without distant metastasis at the end of radiation therapy. Compared with SCC-Ag, patients were less often positive for CYFRA 21-1, but there was a statistically positive correlation between the two markers (correlation matrix=0.69). CONCLUSIONS: CYFRA 21-1 can be used in monitoring the outcome of patients with squamous cell carcinoma of the uterine cervix. It may be particularly useful for patients without SCC-Ag.

Adult↗
PubMed2000

Changes in the liver parenchyma after proton beam radiotherapy: evaluation with MR imaging.

The objective of this study was to describe magnetic resonance (MR) findings with a 1.5T imager for hepatic parenchymal changes after proton beam radiotherapy. Thirty-two patients who received proton radiotherapy with doses of 50-87 Gy underwent MR imaging 1-75 months (mean 22 months) after the start of irradiation. Axial T(2), T(1)-weighted imaging, and a dynamic study after a gadolinium injection were performed. The irradiated areas showed hypointense in T(1)-weighted images, hyperintense in T(2)-weighted images, and intense and prolonged enhancement on the dynamic study (maximum relative enhancement 441.8%+/-263.3 vs. surrounding liver 145.6%+/-67.7, p<0.0001). T(2) values of the irradiated areas were 50.6 to 65.8 msec greater than in the surrounding liver (p<0.005). The values increased with time, being significantly greater 13 months or longer after the beginning of the therapy than after a period of less than 3 months (p<0.05). Pathologic examinations (n = 3) indicated that the irradiated areas were composed of collapsed lobules with hepatic small vein occlusions, and rich extracellular matrices which retained extracellular fluid. MR imaging can demonstrate hepatic parenchymal changes after proton beam radiotherapy, and show the changes are irreversible.

Adult↗
PubMed2000

MR imaging of radiation osteitis in the sacroiliac joints.

The purpose of this study was to analyze magnetic resonance (MR) images of radiation osteitis of sacroiliac joints, retrospectively. Seven patients with radiation osteitis, which was diagnosed by pelvic plain radiographs and CT images, underwent MRI. T(1)-weighted spin echo images and T(2)-weighted fast spin echo images were obtained in all patients. Four patients were examined after gadolinium injection. Major signal changes of radiation osteitis were distributed on the iliac side. T(1)-weighted images showed diffuse low intensity both in sacral and iliac sides. T(2)-weighted images showed very low intensity adjacent to sacroiliac joints, but mixed intensity was illustrated apart from joints, and high intensity in the peripheral areas. Radiation osteitis showed slight to mild, but irregular enhancement in four patients after gadolinium administration. MRI can illustrate abnormal bone change distribution and is useful for diagnosing this entity by characteristic intensity patterns on T(1)-weighted images with and without gadolinium and T(2)-weighted image. However, the diagnosis of accompanied insufficiency fractures in the area of radiation osteitis is occasionally difficult with conventional MRI.

Aged↗
PubMed2000

Usefulness of PET with 11C-methionine for the detection of hilar and mediastinal lymph node metastasis in lung cancer.

UNLABELLED: We retrospectively evaluated the usefulness of PET with 11C-methionine (methionine PET) for the diagnosis of lymph node metastases in patients with lung cancer. METHODS: Methionine PET and CT were performed before surgical intervention in 41 patients with primary lung cancer. We evaluated individual lymph nodes by methionine PET along with corresponding CT images. The 11C-methionine accumulation of lymph nodes was assessed semiquantitatively by analysis of the tumor-to-muscle ratio (TMR) and was compared with CT and histological diagnoses. RESULTS: A total of 126 lymph nodes, 36 of which were histologically diagnosed as metastatic, were assessed by CT and methionine PET. The TMR in metastatic lymph nodes (n = 36) was 5.15+/-1.69, whereas that of nonmetastatic lymph nodes (n = 90) was 2.91+/-0.76; this difference was significant (P < 0.0001). The most adequate TMR cutoff value for diagnosis of metastasis based on the results of receiver operating characteristic curve analysis was 4.1. The positive and negative predictive values, sensitivity, specificity, and accuracy of methionine PET were 79.5%, 94.3%, 86.1%, 91.1%, and 89.7%, respectively, and were superior to those of CT (57.6%, P = 0.04; 81.7%, P = 0.008; 52.8%, P = 0.002; 84.4%, NS; and 75.4%, P = 0.002, respectively). All positive nodes that were shown to be true-positive by CT, and 12 of 17 false-negatives on CT were correctly diagnosed by PET. Ten of 14 lymph nodes that were false-positive on CT were also correctly diagnosed by PET. CONCLUSION: Methionine PET appears to be superior to CT for the diagnosis of lymph node metastasis in lung cancer patients. The high negative predictive value of methionine PET suggests that cases in which lymph nodes are enlarged on CT with negative PET analysis may be diagnosed as negative for metastasis.

Carbon Radioisotopes↗
PubMed1999

Relationship between p21/WAF-1/CIP-1 and apoptosis in cervical cancer during radiation therapy.

PURPOSE: P21/WAF-1/CIP-1 was not considered to be involved in the regulation of apoptosis, an important indicator of radiosensitivity. However, it has been reported recently that apoptosis was suppressed when p21 expressed. The purpose of this study was to clarify the relationship between p21 and apoptosis and to evaluate the role of p21 in cervical cancer during radiation therapy (RT). METHODS AND MATERIALS: Twenty-one patients with cervical cancer were treated by RT. Tissue samples were obtained from cervical tumors of all patients before RT, and 6 hours after the fifth dose of 1.8 Gy (5th Dose). Samples were subjected to nick end labeling for apoptosis and immunohistochemical staining for p21 and p53 antigen expression. RESULTS: The mean apoptotic index, p21 labeling index and p53 labeling index were 0.27%, 9.24% and 6.60%, respectively, before RT and increased significantly to 1.20%, 17.5% and 13.9%, respectively, after 5th Dose. The apoptotic index at 5th Dose was inversely correlated with the p21 labeling index (r = -0.50, p = 0.025). Furthermore, a positive correlation was observed between the p21 and p53 labeling indices both before RT and at 5th Dose (r = 0.52, p = 0. 02; r = 0.63, p < 0.01, respectively). CONCLUSION: Our results demonstrate that apoptosis and expression of p21 and p53 were induced in cervical cancer during RT. p21 expression was dependent on p53 expression and moreover, it is suggested-that p21 might be a potential suppressor of radiation-induced apoptosis in cervical cancer during RT.

Aged↗