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M Koga

Publications and source records attributed to M Koga.

At least 37 records · Page 2Linked to original sources
PubMed2004

High sensitivity search for nu;e's from the sun and other sources at KamLAND.

Data corresponding to a KamLAND detector exposure of 0.28 kton yr has been used to search for nu;(e)'s in the energy range 8.3<E(nu;(e))<14.8 MeV. No candidates were found for an expected background of 1.1+/-0.4 events. This result can be used to obtain a limit on nu;(e) fluxes of any origin. Assuming that all nu;(e) flux has its origin in the Sun and has the characteristic 8B solar nu(e) energy spectrum, we obtain an upper limit of 3.7 x 10(2) cm(-2) s(-1) (90% C.L.) on the nu;(e) flux. We interpret this limit, corresponding to 2.8 x 10(-4) of the standard solar model 8B nu(e) flux, in the framework of spin-flavor precession and neutrino decay models.

Journal Article↗
PubMed2004

Improvement of dermatitis by iontophoretically delivered antisense oligonucleotides for interleukin-10 in NC/Nga mice.

IL-10 is overexpressed in skin lesions of atopic dermatitis (AD) patients and believed to be an important factor in the pathogenesis of the disease. Thus the regulation of IL-10 production is a potential solution for immunotherapeutic intervention in AD. We examined the topical delivery of an antisense oligonucleotide for mouse IL-10 (AS6) and the therapeutic effect on the skin lesions of NC/Nga mice, a human AD model. Using an iontophoresis system, about 30% of the applied dose of AS6 penetrated the skin and was distributed in the epidermis and upper dermis. Topically delivered AS6 decreased the levels of mRNA and protein of IL-10 in the lesions of NC/Nga mice, with no effect on IL-4 levels. The dorsal lesions of NC/Nga mice disappeared with repeated topical application of AS6. Topically delivered AS6 showed an inhibitory effect on the production of IL-10 in the skin lesions of NC/Nga mice and had a therapeutic effect on the established dermatitis.

Animals↗
PubMed2004

Strong association of C-reactive protein with body mass index and 2-h post-challenge glucose in non-diabetic, non-smoker subjects without hypertension.

AIMS: Increases in C-reactive protein (CRP) levels have been shown to be associated with cardiovascular diseases as well as asymptomatic atherosclerosis and to be closely related to traditional cardiovascular risk factors. The aim of this study was to determine the clinical and biochemical characteristics associated with CRP in non-diabetic, non-smoker subjects without hypertension. METHODS: A 75-g oral glucose tolerance test was performed on 305 Japanese subjects aged 40-70 years who were undergoing health examinations. We recruited non-diabetic, non-smoker subjects without hypertension. Subjects with known cardiovascular diseases, chronic or acute inflammation, malignant diseases, or autoimmune disorders were excluded. Plasma high-sensitivity CRP was measured in 125 subjects who satisfied the admission criteria. RESULTS: Plasma CRP levels were significantly higher in the 28 subjects with impaired glucose tolerance (IGT) than that in the 97 subjects with normal glucose tolerance (NGT) (median 0.53, range 0.18-1.10 mg/l vs. median 0.32, range 0.17-0.49 mg/l; P = 0.032). There was a positive correlation of CRP with body mass index (BMI), triglycerides, uric acid, fasting glucose, oral glucose tolerance test (OGTT) 1-h glucose, OGTT 2-h glucose, and a negative correlation with HDL cholesterol. Multivariate regression analysis identified BMI (F = 8.57, P = 0.004) and OGTT 2-h glucose (F = 5.96, P = 0.016) as independent predictors for CRP. CONCLUSIONS: BMI and OGTT 2-h glucose are the most important predictors for plasma CRP in non-diabetic, non-smoker subjects without hypertension.

Adult↗
PubMed2004

Analysis of cellular localization of SART3 tumor antigen by a newly established monoclonal antibody: heterotopic expression of SART3 on the surface of B-lineage leukemic cells.

SART3 has been identified as a tumor antigen recognized by cytotoxic T-lymphocytes. Subcellular localization of SART3 is still controversial, although it has been studied extensively. In this study, we established an anti-SART3 monoclonal antibody (mAb) to analyze the subcellular localization of SART3 in tumor specimens. Immunohistochemical analysis demonstrated that SART3 was preferentially expressed in the nucleus of cancer cells. Flow cytometric analysis indicated that SART3 was not expressed on the cell surface of tumor cells, except for B-lineage cells. SART3 was detected on the cell surface of several B-lineage leukemic cells with different maturation stages, but not on normal peripheral blood B cells. These results suggest that heterotopically expressed SART3 is a tumor-associated antigen rather than a differentiation antigen on B-lineage cells.

Animals↗
PubMed2003

Anti-GM1 antibody IgG subclass: a clinical recovery predictor in Guillain-Barré syndrome.

OBJECTIVE: To determine whether the anti-GM1 antibody IgG subclass (IgG1 to 4) is associated with clinical profiles and patterns of recovery in Guillain-Barré syndrome (GBS). METHODS: The IgG subclassification of anti-GM1 antibody was examined and compared with clinical data on 42 GBS patients positive for the antibody. RESULTS: Frequent anti-GM1 antibody subclasses were IgG1 (76%) and IgG3 (31%). IgG1 antibody was associated with preceding gastroenteritis and Campylobacter jejuni serology, whereas IgG3 antibody was associated with preceding respiratory infection. Although the severity at nadir was similar for IgG1- and IgG3-positive patients, the percentage of patients who could not walk independently was greater for the IgG1-positive group 1 month (42 vs 0%; p = 0.02), 3 months (28 vs 0%), and 6 months (25 vs 0%) after onset. Rapid recovery within 1 month occurred frequently in the patients with the IgG3 antibody but rarely in those with the IgG1 antibody (67 vs 11%; p = 0.003). CONCLUSIONS: The IgG1 subclass of anti-GM1 antibody is a major subtype indicative of slow recovery, whereas isolated elevation of IgG3 subclass antibody titer suggests rapid recovery. Variation in subclass patterns may depend on which pathogen precipitates GBS.

Adult↗
PubMed2003

Washout studies of 11C in rabbit thigh muscle implanted by secondary beams of HIMAC.

Heavy ion therapy has two definite advantages: good dose localization and higher biological effect. Range calculation of the heavy ions is an important factor in treatment planning. X-ray CT numbers are used to estimate the heavy ion range by looking up values in a conversion table which relates empirically photon attenuation in tissues to particle stopping power; this is one source of uncertainty in the treatment planning. Use of positron emitting radioactive beams along with a positron emission tomograph or a positron camera gives range information and may be used as a means of checking in heavy ion treatment planning. However, the metabolism of the implanted positron emitters in a living object is unpredictable because the chemical forms of these emitters are unknown and the metabolism is dependent on the organ species and may be influenced by many factors such as blood flow rate and fluid components present. In this paper, the washout rate of 11C activity implanted by injecting energetic 11C beams into thigh muscle of a rear leg of a rabbit is presented. The washout was found to consist of two components, the shorter one was about 4.2 +/- 1.1 min and the longer one ranged from 91 to 124 min. About one third of the implanted beta+ activity can be used for imaging and the rest was washed out of the target area.

Animals↗
PubMed2003

Improvement of rice (Oryza sativa L.) seed oil quality through introduction of a soybean microsomal omega-3 fatty acid desaturase gene.

Microsomal omega-3 fatty acid desaturase is an essential enzyme in the production of the n-3 polyunsaturated fatty acid alpha-linolenic acid during the seed developing stage. We have constructed a chimeric gene consisting of a maize Ubi1-P-int and a soybean GmFAD3 cDNA, which was introduced into rice plants by Agrobacterium-mediated transformation. Ten transformants containing the chimeric gene were established and expression subsequently confirmed by Northern blotting. Furthermore, alpha-linolenic acid content of the T(1) seeds increased dramatically up to tenfold that of the control, and this phenotype was also stably inherited in the T(2) and T(3) progenies. These results demonstrate that the alpha-linolenic acid content of rice seed oil can easily be altered using the combination of a high-activity promoter and a GmFAD3 gene.

Blotting, Northern↗
PubMed2003

First results from KamLAND: evidence for reactor antineutrino disappearance.

KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded.

Journal Article↗
PubMed2003

Identification of ribosomal proteins S2 and L10a as tumor antigens recognized by HLA-A26-restricted CTL.

Recent identification of cytotoxic T lymphocyte (CTL)-directed peptides binding to the HLA-A2 and -A24 alleles has opened the door to peptide-based cancer immunotherapies. However, subsequent studies have succeeded in identifying no more than a few CTL-directed peptides that bind to alleles other than HLA-A2 and -A24, thus hampering development of immunotherapies directed at other alleles. We have shown in this study that two genes coding for ribosomal proteins (S2 and L10a) encoded tumor antigens recognized by HLA-A26-restricted CTLs. The S2 mRNA was expressed in all of the cancer cells and non-malignant cell lines tested, but was not expressed in normal tissues except for the testis, muscle, and peripheral mononuclear leukocyte cell (PBMC). In contrast, the L10a mRNA was expressed in all of these cancer and non-malignant cell lines, and also normal tissues, although the expression levels in normal tissues were mostly low. One S2-derived peptide and two L10a-derived peptides had the ability to induce HLA-A26-restricted and peptide-specific CTLs reactive to tumor cells in PBMCs of cancer patients, respectively. These ribosomal protein-derived peptides, and particularly the S2-derived peptide, could be suitable for use in peptide-based immunotherapy for HLA-A26+ cancer patients.

Amino Acid Sequence↗
PubMed2003

Differential expression of succinyl CoA transferase (SCOT) genes in somatic and germline cells of the mouse testis.

Succinyl CoA:3-oxo acid CoA transferase (SCOT/OXCT; EC 2.8.3.5) is a key mitochondrial enzyme in the metabolism of ketone bodies in various organs (but not in the liver). We identified a cDNA clone of the testicular germ cell-specific succinyl CoA transferase isozyme (SCOT-t). We then isolated a mouse orthologue of the SCOT/OXCT cDNA (SCOT-s) and determined the expression of the two types of SCOT in the testis. The mRNAs of scot-s and scot-t were expressed exclusively in testicular somatic cells (i.e. Leydig and Sertoli cells) and germ cells, respectively. SCOT enzymatic activities were assayed in Leydig cell (SCOT-s) and sperm (SCOT-t) fractions. The SCOT activity in sperm was 2.5-fold higher than that in Leydig cells. We conclude that germ cells and somatic cells differentially express the SCOT enzymes and that the SCOT activity of sperm caused exclusively by SCOT-t should play an important role in sperm activity.

Animals↗
PubMed2003

Reappraisal of early CT signs to predict the arterial occlusion site in acute embolic stroke.

OBJECTIVE: To elucidate the value of early computed tomographic (CT) signs of stroke in predicting the occlusion site in the cerebral arteries. PATIENTS: 105 consecutive patients with acute embolic stroke affecting the anterior circulation. METHODS: Four early signs were evaluated on cranial CT within six hours of stroke onset: loss of the insular ribbon (LIR); attenuation of the lentiform nucleus (ALN); hemispherical sulcus effacement (HSE); and the hyperdense middle cerebral artery sign (HMCAS). The arterial occlusion site was definitively identified on cerebral angiography within two hours of the CT examination. RESULTS: LIR was present in 55% of patients with internal carotid artery occlusion. ALN was present in 65% of patients with occlusion of the sphenoidal portion (M1) of the middle cerebral artery. HSE was present in 47% of patients with middle cerebral artery branch occlusion. LIR was related independently to internal carotid artery occlusion (odds ratio (OR) 2.8 (95% confidence interval, 1.2 to 6.8)), ALN to M1 occlusion (OR 2.9 (1.2 to 7.4)), and isolated HSE without ALN or LIR to branch occlusion (OR 12.8 (3.2 to 51.5)). The combined presence of the three signs was indicative of internal carotid artery occlusion (p < 0.05), and the presence of ALN and LIR without HSE was indicative of M1 occlusion (p < 0.05) by univariate analysis. HMCAS bore no relation to either arterial occlusion site. CONCLUSIONS: LIR, ALS, HSE, and combinations of these were useful predictors of the arterial occlusion site.

Adult↗
PubMed2003

[The effect of intra-aortic balloon pumping on the graft of coronary artery bypass grafting].

The effect of intra-aortic balloon pumping (IABP) on the graft of coronary artery bypass grafting (CABG) was examined. These patients needed IABP when they were weaned from cardiopulmonary bypass. The flow wave pattern in the graft was acquired and analyze by the slope, peak flow rate and area of systolic phase and diastolic phase. The flow wave pattern different between graft to a left anterior branch and the graft to the right coronary artery. IABP was significantly effective for the flow to the left anterior branch. However, the effect of IABP on the graft flow to the right coronary artery was not significant. In the natural heart, the flow rate of the left coronary artery predominates during the diastolic phase. However this predominance is not clear in the right coronary artery. Our results suggested that this phenomenon in the natural state caused a difference the flow wave pattern between graft of left coronary artery and that of the right coronary artery.

Aged↗
PubMed2002

Effect of hot water extract from Agaricus blazei Murill on antibody-producing cells in mice.

We investigated the immunopotentiating activities of boiled water-soluble extracts from desiccated Agaricus blazei Murill (ABM). Effect of ABM extract on antibody production was investigated by method of hemolytic plaque-forming cells (PFC) against sheep red blood cells (SRBC) antigen. ABM extracts significantly (p<0.01) increased the number of PFC in spleen with intraperitoneal administration at doses of 25 mg/kg as compared with control group. The populations of Mac-1- or CD25-positive cells significantly (p<0.01, p<0.001) increased, but in CD19-positive cells, there were no differences in ABM-treated mice as compared with control mice. The expressions of IL-6 and IL-1beta mRNA were augmented by ABM extract in both peritoneal macrophages and spleen cells. These results suggested that ABM extract might be an effective stimulator for T cell and macrophage to IL-1beta and IL-6 release, resulting in augmentation of antibody production against SRBC antigen.

Agaricus↗
PubMed2002

Clinical, electrophysiological, and serological overlap between Miller Fisher syndrome and acute sensory ataxic neuropathy.

We report a patient with severe sensory ataxia, areflexia, and ophthalmoplegia with preservation of limb muscle strength. Electrophysiological examinations revealed peripheral sensory nerve involvement. A serological examination showed the elevation of IgG antibodies to various b-series gangliosides as well as GT1a. These indicated that this case is an overlap between acute sensory ataxic neuropathy and Miller Fisher syndrome. Autoantibody is implicated as potential pathogenic agents in some cases of acute sensory ataxic neuropathy.

Acute Disease↗
PubMed2002

Asymmetric pharyngeal-cervical-brachial weakness associated with anti-GT1a IgG antibody.

We report a case of markedly asymmetric pharyngeal-cervical-brachial weakness. Acute progression of symptoms, albuminocytologic dissociation in cerebrospinal fluid, electrophysiologic evidence of demyelination and elevation of IgG anti-GT1 a antibody titer paralleled the clinical course, support the diagnosis of Guillain-Barré syndrome. Guillain-Barré syndrome should be considered in the differential diagnosis of cranial neuropathy, even in cases where there is marked asymmetry.

Acute Disease↗
PubMed2002

[Primary malignant tumor of the aorta].

A 63-year old man suffering from bilateral leg pain was admitted to our hospital with an occlusion of the infrarenal abdominal aorta. A bifurcated dacron graft was implanted and a histological examination of the thrombotic material was performed. Atypical cells were detected in the thrombus leading to an investigation of the thoracic aorta showing an unclear mass in the aortic arch. The tumor was resected and the aorta replaced with a dacron graft. Histology revealed a primary sarcoma. The patient is doing well 6 months after operation.

Angiography↗