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Biomedical subjects

Koji Tsuboi

Publications and source records attributed to Koji Tsuboi.

At least 19 recordsLinked to original sources
PubMed2006

Acute peritonitis and salpingitis associated with streptococcal toxic shock syndrome caused by Lancefield group G alpha-haemolytic Streptococcus dysgalactiae subsp. equisimilis.

The authors treated a patient for what appears to be the first reported occurrence of acute peritonitis and salpingitis associated with streptococcal toxic shock syndrome (STSS). This was caused by Lancefield group G alpha-haemolytic Streptococcus dysgalactiae subsp. equisimilis TKCH2004-001. The isolate showed M protein type stc36 and carried the spegg gene. To the best of the authors' knowledge, the present report represents the first case of STSS complicating acute peritonitis and salpingitis caused by Lancefield group G alpha-haemolytic S. dysgalactiae subsp. equisimilis.

Acute Disease↗
PubMed2006

Excision of juvenile pilocytic astrocytoma of the midbrain after radiotherapy.

A 13-year-old girl presented with consciousness disturbance, right hemiparesis, and impairment of hearing, swallowing, and ocular movements. A magnetic resonance image demonstrated marked hydrocephalus due to a large cystic tumor (40 x 40 x 30 mm) in the midbrain. Emergency ventricular drainage and stereotactic cyst puncture dramatically improved her condition. Since her family did not agree to surgery on the brain stem, radiotherapy was performed after ventriculoperitoneal shunting. Conventional radiotherapy of 50.4 Gy was temporarily effective, and the growth of the tumor was stabilized until approximately 8 months later when regrowth was noticed. At this stage, with the consent of her family, the tumor was removed via an infratentorial supracerebellar approach. The pathological diagnosis was juvenile pilocytic astrocytoma. The postoperative course was uneventful. No recurrence has been observed during the follow-up period of more than 6 years. This case study shows that initial excision may be appropriate for some low-grade focal lesions in the midbrain when the histological diagnosis and consent have been obtained.

Adolescent↗
PubMed2006

Sarcomatous transformation of clival chordoma after charged-particle radiotherapy. Report of two cases.

Skull base chordomas containing a sarcomatous component are extremely rare. Here the authors report two new cases in which a recurrent tumor with a sarcomatous component appeared after the patient had undergone charged-particle radiotherapy. Histological examinations performed in Case 1 revealed some retention of epithelial features in the sarcomatous component, whereas no such regions were observed in Case 2. Both patients had rapidly deteriorating clinical courses and died within 6 months after diagnosis of the recurrent tumor. The authors discuss the significance of the histological subtypes of these tumors for long-term prognosis and their pathogenetic mechanisms in relation to radiotherapy. Although these sarcomatous transformations are rare in conventional chordomas, a careful histological examination and thorough follow-up imaging studies are crucial when treating patients with such lesions.

Adult↗
PubMed2005

Dendritic cell maturation by CD11c- T cells and Valpha24+ natural killer T-cell activation by alpha-galactosylceramide.

Human invariant Valpha24+ natural killer T (NKT) cells display potent antitumor activity upon stimulation. Activation of endogenous Valpha24+ NKT cells would be one strategy for the treatment of cancer patients. For example, dendritic cells (DCs) loaded with a glycolipid NKT cell ligand, alpha-galactosylceramide (alphaGalCer, KRN7000), are a possible tool for the activation and expansion of functional Valpha24+ NKT cells in vivo. In this report, we demonstrate that the levels of expansion and the ability to produce IFN-gamma of Valpha24+ NKT cells induced by alphaGalCer-loaded whole PBMCs cultured with IL-2 and GM-CSF (IL-2/GM-CSF-cultured PBMCs) were superior to those of cells induced by monocyte-derived CD11c+ DCs (moDCs) developed with IL-4 and GM-CSF. Interestingly, CD11c+ cells in the IL-2/GM-CSF-cultured PBMCs showed a mature phenotype without further stimulation and exerted potent stimulatory activity on Valpha24+ NKT cells to enable them to produce IFN-gamma preferentially at an extent equivalent to mature moDCs induced by stimulation with LPS or a cytokine cocktail. Cocultivation with CD11c- cells in the IL-2/GM-CSF-cultured PBMCs induced maturation of moDCs. In particular, CD11c-CD3+ T cells appeared to play important roles in DC maturation. In addition, TNF-alpha was preferentially produced by CD11c-CD3+ T cells in IL-2/GM-CSF-cultured PBMCs and was involved in the maturation of moDCs. Thus, the maturation of DCs induced by CD11c- T cells through TNF-alpha production appears to result in the efficient expansion and activation of Valpha24+ NKT cells to produce IFN-gamma preferentially.

Antigens, CD↗
PubMed2005

Anti-angiogenic and immunomodulatory effect of the herbal medicine "Juzen-taiho-to" on malignant glioma.

Juzen-taiho-to (JTT) is known as a Japanese herbal medicine that increases the immune function via the enhancement of phagocytosis, cytokine induction, and antibody production. Anti-neoplastic effects on malignant gliomas have been reported by means of the enhancement of the immune function in both animals and humans. We evaluated whether JTT has anti-angiogenic effects on malignant glioma growth in vitro and in vivo. In vitro, the anti-proliferative effect of JTT on malignant glioma cells and endothelial cells was assessed by cell proliferation assay. In vivo, a subcutaneous model of malignant glioma with different-aged mice (old, 43 weeks; young, 8 weeks) was used. After oral administration of JTT to mice, their immunological function and angiogenic status of tumor tissues were assessed by flow cytometry and immunohistochemistry, respectively. JTT inhibited human endothelial cell, but not glioma cell, proliferation in vitro. In vivo, the NK (natural killer) cell ratio within PBMC (peripheral blood mononuclear cells) and NK activity of fresh splenocytes obtained from JTT-treated old mice were significantly increased compared to the ratio and activity in control mice. In old mice, the vessel area of tumor tissues in JTT treatment groups was significantly decreased. These enhancements of immunological function and the inhibition of angiogenic activity were not observed in young mice. JTT not only increased host immunological function but also exerted anti-angiogenic effects on malignant glioma growth. JTT would be useful as an adjuvant medicine for malignant gliomas through its enhancement of systemic immunological function and its anti-angiogenic action.

Angiogenesis Inhibitors↗
PubMed2005

Primary cerebral angiitis containing marked xanthoma cells with massive intraparenchymal involvement--case report--.

A 27-year-old woman was referred to our hospital with mild disorientation, bilateral abducens nerve palsy, and mild left hemiparesis. Magnetic resonance (MR) imaging revealed diffuse mass lesions resembling malignant glioma in the right frontal intraparenchymal region, with enhancement of multiple meningeal and intraparenchymal nodules. Partial resection of the frontal lesion was performed. Histological examination revealed that the specimens consisted of brain tissue, with marked perivascular infiltration of histiocytes and sheets of xanthomatous cells. The diagnosis was primary cerebral angiitis containing marked xanthoma cells. Steroid therapy was administered over 1 week. MR imaging showed that the remaining lesions resolved gradually, and had disappeared 2 years after surgery. No neurological symptoms or recurrence of the tumor has been observed during the 6-year period since the operation.

Abducens Nerve Diseases↗
PubMed2005

Advanced Chiari malformation type I with marked spinal cord atrophy. Case report.

The authors discuss the results obtained in patients who underwent foramen magnum decompression for longstanding advanced Chiari I malformation in which marked spinal cord atrophy was present. This 50-year-old woman presented with progressive quadriparesis and sensory disorders. Magnetic resonance imaging revealed the descent of cerebellar tonsils and medulla associated with remarkable C1-L2 spinal cord atrophy. After a C-1 laminectomy-based foramen magnum decompression, arachnoid dissection and duraplasty were undertaken. These procedures resulted in remarkable neurological improvement, even after 40 years of clinical progression. Spinal cord atrophy may be caused by chronic pressure of entrapped cerebrospinal fluid in the spinal canal.

Arnold-Chiari Malformation↗
PubMed2004

Anti-angiogenic effects of SN38 (active metabolite of irinotecan): inhibition of hypoxia-inducible factor 1 alpha (HIF-1alpha)/vascular endothelial growth factor (VEGF) expression of glioma and growth of endothelial cells.

PURPOSE: Inhibition of angiogenesis is an important new treatment modality for malignancies, including gliomas. Vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1alpha (HIF-1alpha) have been investigated as potent mediators of tumor angiogenesis. We investigated whether four major chemotherapeutic agents (ACNU, cisplatin, etoposide, and SN38) showed an angiosuppressive effect in vitro. METHOD: The effects of ACNU, cisplatin, etoposide, and SN38 for endothelial cells were assessed by cell growth inhibition assay (WST-8 assay) and vessel formation assay (angiogenesis kit). The inhibitory effects of the HIF-1alpha and VEGF expression of glioma cells after SN38 treatment were assessed by real-time RT-PCR, Western blot, and ELISA. RESULTS: SN38, but not other chemotherapeutic agents, selectively inhibited endothelial cell proliferation and three-dimensional tube formations at the 0.01 microM. Furthermore, SN38 significantly decreased the HIF-1alpha and VEGF expression of glioma cells in a dose- and time-dependent manner under normoxic and hypoxic conditions. SN38 has dual angiosuppressive actions, including both the inhibition of endothelial proliferation and tube formation, and the inhibition of the angiogenic cascade in glioma cells. CONCLUSION: SN38 is an attractive agent as both a direct and indirect angiogenesis inhibitor and provides the anti-glioma agents with an angiosuppressive function.

Angiogenesis Inhibitors↗
PubMed2004

Clinical results of proton beam therapy for skull base chordoma.

PURPOSE: To evaluate clinical results of proton beam therapy for patients with skull base chordoma. METHODS AND MATERIALS: Thirteen patients with skull base chordoma who were treated with proton beams with or without X-rays at the University of Tsukuba between 1989 and 2000 were retrospectively reviewed. A median total tumor dose of 72.0 Gy (range, 63.0-95.0 Gy) was delivered. The patients were followed for a median period of 69.3 months (range, 14.6-123.4 months). RESULTS: The 5-year local control rate was 46.0%. Cause-specific, overall, and disease-free survival rates at 5 years were 72.2%, 66.7%, and 42.2%, respectively. The local control rate was higher, without statistical significance, for those with preoperative tumors <30 mL. Partial or subtotal tumor removal did not yield better local control rates than for patients who underwent biopsy only as the latest surgery. CONCLUSION: Proton beam therapy is effective for patients with skull base chordoma, especially for those with small tumors. For a patient with a tumor of <30 mL with no prior treatment, biopsy without tumor removal seems to be appropriate before proton beam therapy.

Adolescent↗
PubMed2004

Prevalence of eating disorders: a comparison of Western and non-Western countries.

OBJECTIVE: To compare the prevalence of eating disorders between Western and non-Western countries. METHOD: Potential references were identified through an English-language literature search using Medline and Medscape articles. RESULTS: Prevalence rates in Western countries for anorexia nervosa ranged from 0.1% to 5.7% in female subjects. Prevalence rates for bulimia nervosa ranged from 0% to 2.1% in males and from 0.3% to 7.3% in female subjects in Western countries. Prevalence rates in non-Western countries for bulimia nervosa ranged from 0.46% to 3.2% in female subjects. Studies of eating attitudes indicate abnormal eating attitudes in non-Western countries have been gradually increasing. CONCLUSION: The prevalence of eating disorders in non-Western countries is lower than that of the Western countries but appears to be increasing.

Adolescent↗
PubMed2004

X-irradiation to human malignant glioma cells enhances the cytotoxicity of autologous killer lymphocytes under specific conditions.

PURPOSE: To clarify the effect of combining x-irradiation and human killer lymphocytes against autologous malignant glioma cells, we analyzed not only the alteration of surface antigen expression in irradiated tumor cells, but also the cytotoxic effects of human killer lymphocytes on the autologous tumor cells with and without x-irradiation. METHODS AND MATERIALS: Six malignant glioma cell-lines (MG 1-6) established from each patient with a malignant glioma in our institute, and U87MG, were used as materials. They were irradiated by 0-50 Gy of X-rays, and the alternations of their human histocompatability leukocyte antigen (HLA), HLA-ABC, HLA-DR, -DP, -DQ, and FAS expressions were examined. Then, three sets of autologous natural killer (NK) cells, and autologous tumor-specific T lymphocytes (ATTL) were induced from the peripheral blood mononuclear cells (PBMCs) of three patients, and in vitro cytotoxic effects of these killer cells on the irradiated autologous tumor cells were analyzed. RESULTS: Irradiation-enhanced HLA-DR, -DP, -DQ, and FAS expression in glioma cell lines with low p53 expression. However, there was no correlation between HLA-ABC expression and X-ray dose. After irradiation of the tumor cells, cytotoxicity was enhanced in four of six effectors; in particular, it was significantly elevated in two killer lymphocytes. It was speculated that the enhancing effect was influenced not only by the p53 status of the tumor, but also by the types of killer lymphocytes; the alteration of cytotoxicity in NK cells on irradiated tumor cells may be compensatory for alteration in ATTLs. CONCLUSION: It was indicated that irradiation of malignant tumor cells enhanced killer cell-mediated cytotoxicity in autologous models under specific conditions. These basic data should contribute to clinical trials using local radiotherapy and systemic adoptive immunotherapy with killer lymphocytes.

Cytotoxicity, Immunologic↗
PubMed2004

Cancer-related attitudes: A comparative study in Japan and the US.

The cancer-related attitudes and beliefs of adults living in central Japan (N = 357) were compared to those of respondents in a US state (Hawaii) (N = 223) consisting of both Japanese (n = 106) and Caucasian (n = 117) individuals. Almost all US subjects endorsed doctors disclosing cancer diagnoses to their patients, while a minority of the Japan sample supported cancer disclosure as a general practice. However, the majority of Japan respondents expressed a personal preference to be told if they themselves were diagnosed with cancer, as did virtually all US respondents. US subjects were more optimistic than Japanese subjects about cancer's curability, both at the present time and in the future; Japanese Americans scored intermediate between Japanese and Caucasian Americans. Word-association data indicated that cancer was most likely to be associated with death by Japanese respondents. The data support the continued international differences in views about cancer and suggest that some of these differences persist over many generations of US residence.

Adult↗
PubMed2004

Angiogenesis and antiangiogenic therapy for malignant gliomas.

Angiogenesis is crucial to the growth of malignant gliomas. Therefore, antiangiogenic therapy represents a new, promising therapeutic modality for malignant gliomas. This study was designed to define the malignant glioma cases most suitable for antiangiogenic therapy in humans and to demonstrate the efficacy of antiangiogenic therapy in animals. Protein expression of the most potent angiogenic factor, vascular endothelial growth factor (VEGF), and its specific natural inhibitor, soluble Flt-1, as well as vessel architecture, including vessel density, area, and diameter, was evaluated in human malignant glioma samples (24 glioblastomas, 13 anaplastic astrocytomas). Among these, VEGF >1000ng/ml, VEGF/soluble Fltl ratio >1, vessel density >30, and vessel area >7% were prognostic factors for malignant gliomas. Based on these results, we performed three different antiangiogenic experiments targeted to inhibit VEGF expression in a human malignant glioma (U87) mouse model: anti-VEGF neutralized antibody intraperitoneal injection; interferon-beta intramusclar injection; and transfection of an endogenous nonspecific angiogenesis inhibitor, thrombospondin-1, into glioma cells caused inhibition of VEGF secretion and/or mRNA expression and resulted in glioma growth inhibition of 70%, 84%, and 50%, respectively, compared with control. We conclude that malignant gliomas with high degrees of VEGF expression and vessel areas are good candidates for antiangiogenic therapy, especially that designed to inhibit VEGF expression.

Angiogenesis Inhibitors↗
PubMed2004

Surgery improves vision and cosmetic appearance of an adult patient with fibrous dysplasia of the frontal bone.

A 31-year-old woman with fibrous dysplasia (FD) of the left forehead was reported. Visual acuity impairment and diplopia were slowly progressive for 6 months associated with marked protrusion of her left forehead. Removal of left forehead lesion including the orbital ridge and total decompression of the optic canal and superior orbital fissure improved these visual symptoms dramatically. Reconstructive cranioplasty using artificial bone made by hydroxyapatite (Apaceram) was very satisfactory in cosmetic appearance. Surgical indication and neuroradiological findings of cranial FD are discussed as well as a review of the literatures.

Adult↗
PubMed2004

Cerebral metastasis from angiosarcoma of the aortic wall: case report.

BACKGROUND: Primary or metastatic cerebral angiosarcoma is extremely rare, and only limited cases have been reported. The authors here describe a case of angiosarcoma, which was initially identified and diagnosed by the cerebral metastatic lesion; later examinations suggested that the primary site was the abdominal aorta. CASE DESCRIPTION: A 53-year-old man, who had suffered an abdominal aortic aneurysm 2 months earlier, experienced a sudden onset of left-sided hemifacial convulsion and dysarthric speech. Computed tomography (CT) showed a hemorrhagic mass lesion with perifocal edema in the right frontal lobe. Magnetic resonance imaging (MRI) showed a regionally marked hypointensity in the mass lesion on both T1- and T2-weighted images, which might suggest hemosiderin deposition. The tumor was removed in its entirety. Pathologic examination revealed an old hematoma with a hemosiderin deposit containing markedly atypical tumor cells, and angiosarcoma was diagnosed. Resection of the abdominal aortic aneurysm and iliac bone biopsy were performed and angiosarcoma was recognized in each surgical specimen. Based on clinical and pathologic findings, the primary site was considered to be the abdominal aorta. CONCLUSIONS: Clinicians should be aware of this rare histologic type of tumor. Unique MRI findings such as those obtained in our case might be useful for differentiating this condition from other intracranial neoplasms.

Aorta, Abdominal↗
PubMed2004

Health attitudes and behaviors: comparison of Japanese and Americans of Japanese and European Ancestry.

Adults living in Japan (N = 357) and the US (N = 223) completed semi-structured interviews assessing health-related attitudes and practices. The US respondents were of Japanese (N = 106) and European (N = 117) ancestry. Results indicated considerable similarity between the two US groups and significant differences between the Japanese and American respondents. The Japanese respondents placed less priority on health, had less belief in the efficacy of health screening tests, lower levels of internal health locus of control (HLOC), and higher levels of chance and powerful-others HLOC. While Japanese and Americans had similar overall levels of healthy behaviors, the Japanese were less likely to have obtained health screening tests (especially gynecologic exams). The findings have implications for adapting health promotion programs in the context of Japanese and American cultures.

Asian People↗