Search PubMed⌕ Search

Biomedical subjects

T Soejima

Publications and source records attributed to T Soejima.

At least 19 recordsLinked to original sources
PubMed2000

Target cells of apoptosis in the adult murine dentate gyrus and O4 immunoreactivity after ionizing radiation.

The occurrence of radiation-induced apoptosis and the determination of target cells were investigated by using the TdT-mediated dUTP-biotin nick end labeling assay and immunohistochemical analyses. The O4 immunoreactivity, an oligodendrocytes surface antigen, was also evaluated by using western blotting analysis. C57BL/6J adult female mice were subjected to single dose irradiation of 10 Gy. Eight hours after irradiation, the most significant increase of apoptotic cells was detected in the subgranular zone and the hilus of the dentate gyrus. The target cells of radiation-induced apoptosis are the subgranular progenitor cells and the oligodendrocytes in the hilus. The amount of the O4 immunoreactivity, a marker for premature oligodendrocytes, was unchanged until 8 h but enhanced after 12 h of irradiation. These results are the first to show the increase of the O4 immunoreactivity after irradiation and may be associated with the pathogenesis of radiation injury.

Animals↗
PubMed1999

Tachykinin-induced responses via neurokinin-1 and -3 receptors in hamster submandibular ganglion neurones.

Both substance P and neurokinin A are known as neurotransmitters of the submandibular ganglion cell. In this study, the effects of neurokinin (NK) receptor-subtype agonists on hamster submandibular ganglion cells were investigated using the whole-cell patch-clamp technique. Membrane currents evoked by a ramp pulse from +50 to -100 mV (-150 mV/1000 msec) were compared in both the absence and presence of NK receptor agonist. The NK-1 receptor agonist [Sar9, Met (O2)11]-substance P, the NK-2 receptor agonist [Ala5, beta-Ala8]-alpha-neurokinin fragment 4-10, and the NK-3 receptor agonist senktide were used. The three agonists dose-dependently increased the amplitude of the inward current with a reversal potential near 0 mV. Their rank order was NK-1 = NK-3 > NK-2. Even when the external solution was replaced with Cs+ or N-methyl-D-glucamine+ instead of Na+, the NK receptor agonists also increased the amplitude of the inward current. Thus, NK-1 and NK-3 receptors are apparently coupled with non-selective cation channels in submandibular ganglion cells.

Animals↗
PubMed1999

Analysis of strain distribution in the medial collateral ligament using a photoelastic coating method.

The strain distribution over the entire medial collateral ligament (MCL) was measured using a photoelastic coating method. This new approach utilized a polyurethane monomer as a photoelastic coating film. The initial experiments investigating MCL strain measurement showed that this film had a high sensitivity for strain and good adhesion to the ligament. It was confirmed that strain distribution could be obtained qualitatively over the entire ligament using this method. The mechanism of MCL injury was studied by applying this polyurethane coating film to the entire MCL in a femur-MCL-tibia complex. When simple tension was applied to the complex, strain concentrations were centred at the tibial insertion site, and all the specimens ruptured at the MCL tibial insertion site. With application of a valgus bending moment, increased strain was seen in the MCL from the medial femoral condyle to the medial epicondyle. Histological analysis demonstrated midsubstance ligament ruptures in this same region. For both tests, rupture sites and increased strain concentration sites correlated. In addition, an impingement phenomenon of the MCL on the medial femoral condyle can be seen during application of valgus force, and this phenomenon may explain the higher incidence of MCL injuries on the femoral side seen in the clinical setting. This polyurethane coating method allows for direct and visual measurements, and can qualitatively measure the strain behaviour over the entire MCL surface. This new technique represents a significant improvement over previous point-by-point strain measurement methods.

Animals↗
PubMed1998

Multivariate analysis of single unit cells in electron crystallography.

High-resolution electron cryomicroscopy of two-dimensional protein crystals is associated with extremely noisy raw data in which even the crystal lattice often cannot be discerned. Correlation averaging procedures, aimed at calculating the total average of all unit cells of crystals in order to reduce noise, are now used routinely in electron crystallography. Multivariate statistical analysis (MSA) may be used for finding not only the average structure but also for quantifying the systematic departures from that average within the population of individual unit cells. We show that the MSA approach is applicable to single unit-cell images in the low-dose (< 10 electrons/A2), high-resolution (< 5 A) realm using 400 keV electron spot-scan images of ice-embedded gp32*I protein crystals. Our feasibility study opens a pathway toward exploiting these naturally occurring variations on the unit-cell theme in order to achieve higher-resolution three-dimensional reconstruction results, or to better understand the dynamic behaviour of molecules within two-dimensional crystals. We explain how single unit-cell images can be processed and classified into homogeneous groups, and we review how the results of such discriminate averaging may subsequently be exploited within the context of conventional "h, k"-space electron crystallographic approaches. Variations among the individual unit cells may thus be one of the most significant resolution-limiting factors currently experienced in electron crystallography. The quantitative assessment and exploitation of such variations may lead to an increased performance of electron crystallographic procedures.

Bacteriophage T4↗
PubMed1998

[Endoscopic findings of esophagitis in concurrent chemo-radiotherapy for lung cancer].

We performed esophageal endoscopy with concurrent chemo-radiotherapy for lung cancer in 19 patients. Endoscopical examination proved that seven patients (36.8%) had esophageal erosion or coating (grade 2), four patients (21.1%) had ulcer or bleeding (grade 3) confined to the radiation field, and only one patient (5.3%) had severe symptoms (WHO grade 3). There was a discrepancy between patients' symptoms and endoscopical findings. Endoscopically proven esophagitis, that is, erosion or coating (grade 2), and ulcer or bleeding (grade 3), was more frequent in the daily low-dose chemotherapy group (5/5) than in the full dose chemotherapy group (5/14) (p < 0.05). One patient with grade 3 endoscopial damage showed less recovery in spite of three months medication. In concurrent radiochemotherapy in which the radiation field includes the esophagus, careful attention should be given to radiation esophagitis, which may be underestimated when assessed on the basis of subjective symptoms alone. Therefore, endoscopy is recommended even if patients have few complaints, and once the esophageal ulcer is proven (grade 3), it should be closely followed up using endoscopy.

Adult↗
PubMed1998

Substance P-induced depolarization accompanied by a decrease in membrane input resistance in the hamster submandibular ganglion cell.

We described in a previous paper (Bull Tokyo dent Coll 33: 33-35, 1992) that the submandibular ganglion cells (SMG) of hamster responded to substance P (SP) with a depolarization, which could be divided into three subtypes according to the change in membrane input resistance (Rm) during depolarization: depolarizations accompanied by either an increase or a decrease in Rm, and without change in Rm. In this study, the generation mechanism of the SP-induced depolarization accompanied by a decrease in Rm was investigated using the current-clamp technique. The result showed that cation channels coupled with NK-1 receptors on SMG cells were involved in generation of the SP-depolarization, and that the main charge carrier was the sodium ion.

Animals↗
PubMed1997

[Radiation therapy for adrenal metastases].

PURPOSE: To evaluate the role of radiation therapy for adrenal metastases. MATERIALS AND METHODS: Fourteen patients, 13 with primary lung carcinoma and one with primary unknown carcinoma, received radiation therapy for adrenal metastases from 1984 to 1995 at the Hyogo Medical Center for Adults. Total dose ranged from 16 Gy to 60 Gy, and fractional dose from 1.6 Gy/ Fr to 3 Gy/Fr. RESULTS: Partial response of the local tumor was recognized in 2 of 7 patients by CT imaging. Pain relief was obtained in 7 of 8 patients. Median survival was 3 months, and 6-month survival was 28.6% in all patients. Among patients in the symptomatic group, who had complaints of pain due to adrenal mass, survival was even worse (12.5% at 6 months). There were no severe complications, but 4 patients (29%) had gastrointestinal symptoms. CONCLUSION: Radiation therapy is useful for the purpose of pain relief in adrenal metastases.

Adrenal Gland Neoplasms↗
PubMed1997

[Analysis of in-field and marginal relapse in stage I/II non-Hodgkin's lymphoma treated with radiotherapy].

One hundred sixty-three patients with previously untreated stage I/II non-Hodgkin's lymphoma were analyzed as to their in-field and marginal relapse of the irradiated field following treatment with more than 30 Gy of radiotherapy between 1981 and 1995 at Hyogo Medical Center for Adults. Local regrowth in case of partial response was counted as in-field relapse. Complete response was obtained in 94.5% of the cases at the termination of radiotherapy and in 98.8% finally. The ten-year cumulative in-field relapse and marginal relapse rates were 5% and 8.7%, respectively. The cumulative in-field relapse rate (CIFRR) in cases of bulky disease (more than 5 cm in largest diameter of the tumor) was significantly higher than in those of non-bulky disease (26.1% in 8 years vs 2.4% in 10 years, P < 0.01). The radiation dosage delivered (40 Gy = < and 50 Gy > vs 50 Gy < =) a great much difference in cases of bulky disease (23.8% for 8-year CIFRR vs 0% for 1-year CIFRR, respectively), but less difference with non-bulky disease (2.6% vs 2.2%). High LDH and suboptimal dose chemotherapy (three courses and less chemotherapy containing ADM or its derivatives, chemotherapy without ADM or no chemotherapy) had a negative impact on marginal control in aggressive lymphoma. Extended field setting in aggressive lymphoma was not proven to be beneficial in comparison with involved field setting as to marginal field relapse. Thus, it is concluded that (1) higher doses should be given to bulky disease, (2) careful field coverage with enough margin is recommended for aggressive lymphoma with high LDH or treated without optimal dose chemotherapy, and (3) extended field setting is not necessary.

Adolescent↗
PubMed1997

[Radiotherapy for adenocarcinoma of the uterine cervix].

One hundred three patients with adenocarcinoma of the uterine cervix treated with radiotherapy between 1975 and 1992 were evaluated. The results for 24 patients treated with radiotherapy alone were as follows: The overall 5-year survival rates for Stages I + II (N = 12) and III + IV (N = 12) were 52% and 16%, respectively, lower than those for squamous cell carcinoma (stage I: 89%, II: 54%, III: 44%, IV: 19%). The overall response rate was 79.1%, and the recurrence rate was 54.2% (local recurrence: 29.2%, distant metastasis: 33.3%). In Stage I + II patients with an intracavitary irradiation dose of 40 Gy (LDR) or more, there was no local recurrence. In stage III + IV patients, local recurrence was recognized in spite of the high dosage of intracavitary irradiation. The results for 79 patients treated with combined irradiation and operation were as follows: The overall 5-year survival rates for Stages I, II, III and IV were 76%, 60%, 57%, and 0%, respectively. The incidence of lymph node metastasis was 30.4%, and for Stages I, II, III and IV was 26.7%, 34.6%, 28.6%, and 100%, respectively. This showed that adenocarcinoma had a higher incidence of lymph node metastasis after the early stage. The recurrence rate for patients with lymph node metastasis was 75.0%, significantly higher than 25.4% for patients without lymph node metastasis (p < 0.001). To improve prognosis, 40 Gy or more of intracavitary irradiation dose (LDR) and systemic chemotherapy to prevent distant metastasis are recommended for stage I and II cases. For stage III and IV cases, it was thought to be difficult to control local disease with radiation alone. Additional treatment should be used for these cases, i.e. intraarterial infusion, chemotherapy, hyperthermia and so on.

Adenocarcinoma↗
PubMed1996

Radiotherapy after hyperbaric oxygenation for malignant gliomas: a pilot study.

The results of radiotherapy combined with hyperbaric oxygen in 9 patients with malignant glioma were compared with those of radiotherapy without hyperbaric O2 in 12 patients. This is the first report of a pilot study of irradiation immediately after exposure to hyperbaric O2 in humans. All patients receiving this treatment showed more than 50% regression of the tumor, and in 4 of them, the tumors disappeared completely. Only 4 out of 12 patients without hyperbaric O2 showed decreases in tumor size, and all 12 patients died within 36 months. So far, this new regimen seems to be a useful form of radiotherapy for malignant gliomas.

Adolescent↗
PubMed1993

[Radiation therapy for carcinoma of vagina].

Thirty-four patients with carcinoma of the vagina were treated by radiotherapy at the Hyogo Medical Center for Adults between April 1965 and May 1990. All patients were treated with a combination of external and intracavitary or intestinal irradiation. Twenty-three patients had squamous cell carcinoma, five had adenocarcinoma and two had malignant melanoma. The five-year survival of patients with squamous cell carcinoma was 70% in Stage I (10 patients), 40% in Stage II (seven patients), 50% in Stage III (three patients) and 0% in Stage IV (three patients). Local control was achieved in 72.7% of the patients with squamous cell carcinoma and 60% of those with adenocarcinoma. However, neither of the malignant melanomas was controlled. Five patients had severe complications that required surgical treatment: severe proctitis and small-bowel perforation, ileus, rectal stenosis, vesicovaginal fistula and small-bowel perforation. Local and pelvic failure was noted in three patients. Patients with previous hysterectomy were more likely to develop serious treatment-related complications.

Adenocarcinoma↗
PubMed1993

[Radiotherapy for vulvar cancer].

Fifteen patients who had primary vulvar cancer treated with radiotherapy as an initial treatment at Hyogo Medical Center for Adults and Hyogo Cancer Center from January 1971 to December 1990 are presented. Two patients were stage 0, one stage I, three stage II and nine stage III. Nine patients received electron irradiation with or without interstitial irradiation and intracavitary vaginal irradiation. Five patients received megavoltage X-ray irradiation using AP/PA parallel opposed fields including the pelvic nodes and perineum followed by boost irradiation of electrons, interstitial irradiation and intracavitary vaginal irradiation. The total dose delivered to the primary tumor ranged from 50 to 100 Gy (73 Gy on average). The actuarial 5-year survival rate of the patients was 43.6%. Complete regression (CR) was achieved in 60% of the patients. However, CR was not achieved in any of five patients with palpable inguinal nodes. In contrast, all the patients who had tumors of less than 2 cm in diameter achieved CR. Five of nine CR cases relapsed. First sites of failure were vagina, groin and vulvar region. Recurrence occurred more than four years after treatment in three cases. Necrosis occurred in five of nine CR cases.

Adult↗
PubMed1993

Pachymeningoencephalitis: case report.

Hypertrophic cranial pachymeningitis is uncommon. We report the first case of pachymeningitis extending to the cerebral parenchyma (pachymeningoencephalitis) and involving the bone and extracranial soft tissue. The clinical features and pathogenesis are discussed.

Adult↗
PubMed1992

[Histopathological study of the esophageal injury induced by high-dose-rate intracavitary irradiation. Experimental study on the rabbits].

Despite the effectiveness of the intracavitary irradiation as the boost therapy for the esophageal cancer, the side effect of the normal part of the esophagus has not been studied enough. The purpose of this study is to investigate the histopathological responses of the rabbit esophagus to the high-dose-rate intracavitary irradiation. Esophageal ulcer was observed in the specimen received a dose of 15 Gy during 7 to 28 days after irradiation. Before the mucosal changes were observed, edema and cell infiltration were found in lamina propria. Chronic injury such as necrosis and degeneration of epithelium, and degeneration of the wall of blood vessels was seen at 6 months. No marked changes were found in the specimen received doses of 5 and 10 Gy. The influences of administration of mucosal protection agent and cancer chemotherapeutic drug were also studied. Administration of mucosal protection agent protected the occurrence of severe ulcer and accelerated the recovery from mucosal damage. Administration of cancer chemotherapeutic agent enhanced the radiation injury by the intracavitary irradiation of the esophagus. In conclusion, it was strongly suggested that a single dose of the high-dose-rate intracavitary irradiation should be reduced less than 10 Gy to prevent the esophagus from severe injury.

Animals↗
PubMed1992

[Application of CT simulation system to stereotactic radiosurgery--experimental study in phantoms].

Stereotactic radiosurgery with linear accelerator requires accurate localization of target and accurate spatial delivery of radiation. In phantom study, geometric accuracy of radiosurgery was assessed in combination of CT simulation system (CTSS), which had been developed in our institute, and linear accelerator with supplemental collimator. After determination of target and its isocenter with CTSS, phantom was placed on treatment table so that isocenter meet at the intersection of mechanical axes (gantry, turn table). Displacement of the isocenter from the center of the radiation field was 1 mm in average. It was concluded that this combination could be applied to radiosurgery.

Computer Simulation↗
PubMed1992

Cytologic findings of fine needle aspirates in chronic prostatitis.

Cytologic studies in patients with prostatic infection, primarily those with chronic prostatitis, were conducted on samples obtained by the fine needle aspiration method. Infiltration of inflammatory cells such as polymorphonuclear leukocytes and macrophages was observed to a greater extent in patients with chronic bacterial prostatitis as compared to those with chronic nonbacterial prostatitis or prostatodynia. The pathogen was isolated in only one out of 28 patients with chronic bacterial prostatitis. We concluded that fine needle biopsy is useful for assessing patients with prostatic inflammation, but not for detecting microorganisms because of focal colonization of the organisms in the glands.

Bacterial Infections↗
PubMed1992

Establishment and characterization of doxorubicin-resistant human bladder cancer cell line, KK47/ADM.

A human bladder cancer cell line resistant to doxorubicin, KK47/ADM has been established in vitro by exposing KK47 parent cells to progressively higher concentrations of the drug over a period of 16 months. The KK47/ADM was 271 times more resistant to doxorubicin than the KK47 parent. The KK47/ADM exhibited cross-resistance to doxorubicin derivatives (pirarubicin, epirubicin), vinca alkaloids (vinblastine, vincristine) and etoposide, but not to cisplatin, carboplatin, mitomycin C, peplomycin and methotrexate. Unlike the KK47 parent, about 70% of the KK47/ADM cells showed a positive reaction with monoclonal antibody against P-glycoprotein, MRK16. Uptake and efflux studies with [14C]doxorubicin indicated that the resistance exhibited by the KK47/ADM line was mainly due to a lower accumulation of the drug caused by an increased active efflux, and these were reversed in the presence of verapamil. Although verapamil enhanced doxorubicin sensitivity of KK47/ADM, a complete overcoming of the resistance could not be obtained. These two lines with different chemosensitivity are thus considered to be a useful model for developing new chemotherapeutic strategies against multidrug resistant bladder cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗