Publications by authors named "Asai A"

Oligodendrogliomas frequently, but not always show sensitivity to chemotherapy and recent studies demonstrated that allelic loss of chromosome 1p is highly associated with this chemosensitivity. To gain insight into the molecular mechanism of such difference, we examined comprehensive gene expression profiles of 11 oligodendroglial tumors, six with and five without 1pLOH (loss of heterozygosity), and two normal brain tissues using the oligonucleotide microarray (GeneChip). Statistically significant numbers of genes were expressed differentially between the two genetic subsets.

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Although euthanasia has been a pressing ethical and public issue, empirical data are lacking in Japan. We aimed to explore Japanese nurses' attitudes to patients' requests for euthanasia and to estimate the proportion of nurses who have taken active steps to hasten death. A postal survey was conducted between October and December 1999 among all nurse members of the Japanese Association of Palliative Medicine, using a self-administered questionnaire based on the one used in a previous survey with Australian nurses in 1991.

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Mutation of the p53 gene plays a critical role in the development of cancer and response to cancer therapy. To analyze the mechanism of cancer development and to improve cancer therapy, it is important to assess which genes are downstream components of p53 in cancers, and whether the expression levels of these genes affect p53-mediated apoptosis. In this study, we transduced the wild type p53 gene along with the Apaf-1 and caspase-9 genes via adenovirus vectors into U251 and U-373MG glioma cells harbouring a mutated p53, and evaluated the degree of apoptosis.

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Background: p27Kip1 is a potential tumor suppressor gene. As malignant gliomas express Fas at high levels, the relationship between Fas-mediated apoptosis and p27Kip1 expression may improve therapeutic approaches for treating gliomas.

Materials And Methods: In this study, we transduced U-373MG glioma cells with the Fas ligand or caspase-8 genes using adenovirus vectors after transduction of the p27Kip1 gene to induce cell cycle arrest in U-373MG cells, and evaluated the degree of apoptosis.

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Background: The purpose of this study is to explore laypersons' attitudes toward the use of archived (existing) materials such as medical records and biological samples and to compare them with the attitudes of physicians who are involved in medical research.

Methods: Three focus group interviews were conducted, in which seven Japanese male members of the general public, seven female members of the general public and seven physicians participated.

Results: It was revealed that the lay public expressed diverse attitudes towards the use of archived information and samples without informed consent.

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Purpose: The histological diagnosis of human gliomas is of great importance for estimating patient prognosis and guiding therapy but suffers from being subjective and, therefore, variable. We hypothesized that molecular genetic analysis could provide a more objective means to classify tumors and, thus, reduce diagnostic variability.

Experimental Design: We performed molecular genetic analysis on 91 nonselected gliomas for 1p, 19q, 10q, TP53, epidermal growth factor receptor, and cyclin-dependent kinase 4 abnormalities and compared with the consensus diagnoses established among four independent neuropathologists.

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Although radiation injuries to the brain are well documented, immediate early histological changes in the brain remain to be defined. The present study characterizes glial injury provoked in adult rat white matter within 24 h after a single irradiation of the whole brain (10 or 20 Gray). Irradiated brains were histologically and histochemically analyzed.

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Background And Purpose: We sought to examine the relationship between menstrual and reproductive factors and the risk of subarachnoid hemorrhage (SAH), using a case-control study.

Methods: Cases consisted of a consecutive series of 124 women patients with first spontaneous SAH aged 30 to 79 years and confirmed aneurysm(s) by angiography and/or CT scan. Hospital and community controls subjects were identified, matched to each case by age (+/-2 years).

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A growing body of evidence now suggests that programmed cell death (PCD) occurs via non-apoptotic mechanisms as well as by apoptosis. In contrast to apoptosis, however, the molecular mechanisms involved in the regulation of non-apoptotic PCD remain only poorly understood. Here we show that ceramide induces a non-apoptotic PCD with a necrotic-like morphology in human glioma cells.

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Curcumin and its structurally related compounds (curcuminoids), the phenolic yellowish pigments of turmeric, display antioxidative, anticarcinogenic and hypocholesterolemic activities. In this study, we investigated the effects of dietary supplemented curcuminoids [commercial grade curcumin: a mixture of curcumin (73.4%), demethoxycurcumin (16.

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Background: Patients in different countries have different attitudes toward self-determination and medical information. Little is known how much respect Japanese patients feel should be given for their wishes about medical care and for medical information, and what choices they would make in the face of disagreement.

Methods: Ambulatory patients in six clinics of internal medicine at a university hospital were surveyed using a self-administered questionnaire.

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Cavernous malformations (CVMs) and arteriovenous malformations (AVMs) were immunostained for three smooth muscle cell (SMC)-specific protein markers (smooth muscle alpha-actin, SM1 and SM2). Smooth muscle alpha-actin, a widely used marker of SMCs, is reportedly one of the earliest proteins expressed during differentiation of SMCs and expressed in some kinds of mesoderm-derived cells. In contrast, SM1, an isoform of myosin heavy chain (MHC), is detected only in SMCs.

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Objective: To demonstrate Japanese doctors' and nurses' attitudes towards and practices of voluntary euthanasia (VE) and to compare their attitudes and practices in this regard.

Design: Postal survey, conducted between October and December 1999, using a self-administered questionnaire. PARTCIPANTS: All doctor members and nurse members of the Japanese Association of Palliative Medicine.

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We have designed, synthesized, and evaluated using physical, chemical and biochemical assays various oligonucleotide N3'-->P5' phosphoramidates, as potential telomerase inhibitors. Among the prepared compounds were 2'-deoxy, 2'-hydroxy, 2'-methoxy, 2'-ribo-fluoro, and 2'-arabino-fluoro oligonucleotide phosphoramidates, as well as novel N3'-->P5' thio-phosphoramidates. The compounds demonstrated sequence specific and dose dependent activity with IC50 values in the sub-nM to pM concentration range.

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Objective: Conflicting reports have been published with regard to the relationship between the efficacy of p53 gene therapy and the p53 status of gliomas. In this study, we evaluated whether U-87MG glioma cells harboring wild-type p53 and U251 and U-373MG glioma cells harboring mutated p53 demonstrate different sensitivities to p53-induced apoptosis. In addition, we tested whether transduction of Bax or caspase-9, which are downstream components of p53-induced apoptosis, can override the resistance mechanism of U-87MG cells to apoptosis.

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The p53 tumor-suppressor gene plays a critical role in radiation-induced apoptosis. Several genes, including Bax and Fas, are involved in p53-mediated apoptosis, and their over-expression enhances the degree of radiation-induced apoptosis. Apaf-1 and caspase-9 have been reported to be downstream components of p53-mediated apoptosis, suggesting that these genes play a role in radiation-induced apoptosis.

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We report on a patient with ependymoma who had a recurrence after long-term remission. The patient developed frontoparietal ependymoma at the age of one year and ten months. The tumor was radically removed and postoperative radiation therapy was performed.

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The aim of this study is to show the preferences of Japanese dialysis patients for receiving cardiopulmonary resuscitation (CPR) in their current health status, if they were severely demented, or if they had terminal cancer and to determine their desires about continuing dialysis if they were severely demented or had terminal cancer. A questionnaire survey including the three scenarios was administered to 450 dialysis patients in 15 hospitals in JAPAN: Three hundred ninety-eight patients completed the questionnaires for a response rate of 88%. The majority of responding patients were men and were undergoing hemodialysis.

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Purpose: Hyperthermia kills glioma cells by inducing apoptosis and is thereby an effective therapeutic modality for the treatment of malignant gliomas. However, cells harboring mutated p53 are refractory to hyperthermia-induced apoptosis. In this study, we assessed whether or not adenovirus (Adv)-mediated transduction of p53 overrides this resistant mechanism.

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Several apoptosis-related genes have been reported to be involved in chemotherapy-induced apoptosis in cancers. An assessment of the relationship between expression of those genes and the degree of chemotherapy-induced apoptosis may be useful in improving the efficacy of cancer therapy. We transduced Apaf-1 (apoptotic protease-activating factor-1) and caspase-9 into U-373MG glioma cells using adenovirus (Adv) vectors in the presence of etoposide and evaluated the degree of apoptosis.

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Background: Mouse imprinted gene Peg3 encodes a large C2H2 type zinc finger protein with unique characteristics. Peg3 knockout mice were found to show an impairment in maternal behaviour of the adult female. Mouse Peg3 is located on the proximal region of chromosome 7 which is syntenic to the long arm of human chromosome 19.

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Curcuminoids, curcumin and its structurally related compounds, constitute the phenolic yellowish pigment of turmeric. We investigated the absorption and metabolism of orally administered curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin) in rats. HPLC and LC-MS analyses after enzymatic hydrolyses showed that the predominant metabolites in plasma following administration were glucuronides and glucuronide/sulfates (conjugates with both glucuronide and sulfate) of curcuminoids.

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It has been reported that U-87MG glioma cells with wild-type p53 are resistant to p53 replacement gene therapy. As some gliomas harbor wild-type p53, it would be important to override the resistance mechanism due to wild-type p53 in glioma gene therapy. In this study, we transduced U-87MG cells or U251 glioma cells harboring mutated p53 with the p53 or p73alpha gene (a homologue of p53, that differently induces some p53-responsive genes) via adenovirus vectors (Advs) at same multiplicities of infection (MOIs) into respective cells (U-87MG: MOI 1000, U251: MOI 100), and evaluated the degree of apoptosis.

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