Search Results - (Author, Cooperation:H. Sakamoto)

2014-07-22

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Alleles ; Antigenic Variation/genetics ; Chromatin/enzymology ; Down-Regulation/genetics ; Erythrocytes/parasitology ; Exoribonucleases/deficiency/genetics/*metabolism ; *Gene Silencing ; Genes, Protozoan/*genetics ; Humans ; Introns/genetics ; Malaria, Cerebral/*parasitology ; Malaria, Falciparum/parasitology ; Plasmodium falciparum/*enzymology/*genetics/pathogenicity ; Promoter Regions, Genetic/genetics ; Protozoan Proteins/genetics ; RNA, Messenger/genetics/metabolism ; RNA, Protozoan/genetics/*metabolism ; RNA, Untranslated/genetics/metabolism ; Transcription Initiation Site ; Virulence/genetics ; Virulence Factors/genetics

1089-7550

AIP Digital Archive

Physics

We have investigated alignability of anisotropic Nd-Fe-B powders in a magnetic field when they are resin bonded by compression moulding. A high-energy anisotropic powder of Cu-added Nd-Fe-B alloys, which was fabricated by packed rolling of melt-spun ribbons, is used for the present study. The result is compared with the alignability of conventional 2:17 type Sm-Co powder. For a Nd-Fe-B-Cu powder (iHc = 16 kOe), 90% of the saturated Br value was obtained at an aligning field as low as 2 kOe, whereas for a Sm-Co powder (iHc = 12 kOe), an aligning field of 13 kOe was required to obtain the 90% value. The good alignability of the Nd-Fe-B-Cu powder is attributed to a steep rise in the initial magnetization curve. It benefits radial orientation of the powder in ring magnets, for which limitations of the aligning field exist depending upon the size of the magnet. A maximum energy product of 15 MGOe has been obtained for radially oriented Nd-Fe-B-Cu bonded magnets.

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1089-7550

AIP Digital Archive

Physics

A packed-rolling method has been applied to fabricating Nd-Fe-B anisotropic powder from melt-spun ribbons; the method involves packing the ribbon materials in a steel container under a vacuum and rolling the pack at around 700 °C. The hot-rolled materials, which form a bulk in a plate-shape, exhibited a strong deformation-induced magnetic anisotropy with the easy magnetization axis parallel to the plate-thickness direction. The anisotropic powders can be obtained by pulverizing the hot-rolled materials. Hot rolling to an 82% reduction in ribbon thickness produced the following magnetic properties: iHc = 12.3 kOe, Br = 12.3 kG, and (BH)max = 36.8 MGOe for a conventional Nd14Fe80B6 alloy. We have found that additions of Cu increase the coercive force up to 19 kOe and result in a remarkable improvement in thermal stability of the anisotropic powders. The result is interpreted in terms of the suppression of grain growth by Cu additions.

Electronic Resource

1089-7674

AIP Digital Archive

Physics

A field-reversal mechanism in a reversed-field pinch (RFP) is studied through a three-dimensional resistive compressible magnetohydrodynamic (MHD) simulation of the single- and multiple-helicity modes. As the magnetic Reynolds number increases, the m=1 fluctuating magnetic field grows exponentially and extends radially, and then the flow begins to form the vortex structure around the core of the plasma. This radial flow acts such as to push out the toroidal magnetic field. As the dynamo electric field induced by this interaction increases near the core of the plasma, the toroidal magnetic field at the wall decreases toward the negative value and the toroidal magnetic field reverses. As a result, it is found that the field reversal is achieved by the single-helicity evolution of the m=1 mode alone, without the (m=0; n≠0) modes, and the interaction of the radial flow and the toroidal magnetic field is the most dominant source for the dynamo action on the field-reversal process. © 1995 American Institute of Physics.

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1089-7623

AIP Digital Archive

Physics

Electrical Engineering, Measurement and Control Technology

The Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences (NIRS) is the first heavy-ion accelerator complex dedicated to cancer therapy. HIMAC is equipped with two kinds of ion sources. The PIG ion source is an indirectly heated cathode type, which is operated with a very low-duty factor. The ECR ion source has a single closed ECR zone with 10 GHz microwaves. Both sources realize good stability and reproducibility with easy operation, and satisfy the requirements for radiotherapy. They have been successfully used for clinical trials since June of 1994, and several tens of cancer patients have already been treated with 290–400 MeV/u carbon beams. © 1996 American Institute of Physics.

Electronic Resource

1525-1438

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Ten cases of gynecologic malignancies, including three endometrial, two ovarian and four cervical carcinomas, were studied for the expression of a 185 kDa protein (ErbB-2), coded by a proto-oncogene, c-erbB-2, in primary lesions as well as in metastatic lesions. Positive immunoreactivity was observed in all primary adenocarcinomas but not from squamous cell carcinomas. Many adenocarcinoma cells in distant metastatic sites or in tertiary lymph nodes were strongly stained for ErbB-2. These metastatic cells also showed an expression of proliferating cell nuclear antigen (PCNA). Detection of ErbB-2 mRNA by a reverse-transcription polymerase chain reaction showed that the transcription occurred exclusively in adenocarcinomas. To our knowledge, this is the first report demonstrating ErbB-2 expression in distant metastatic lesions of gynecologic cancers.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

A unique method of hot rolling is described which fabricates high performance plate-shaped magnets from a cast Pr17Fe76.5B5Cu1.5 alloy. A flat ingot of the alloy with fine-scale columnar grains of a Pr2Fe14B phase is prepared by chill casting. The ingot is hot rolled in such a way that the roll pressure is applied perpendicular to the preferential growth direction of the columnar grains. A maximum energy product of 25.3 MG Oe has been obtained by this method.

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1089-7550

AIP Digital Archive

Physics

The effects of Si and Al on magnetic properties of melt-spun Nd-Fe-B base alloy permanent magnets were studied. The addition of Si to the Nd-Fe-B base alloy improves magnetic properties: it especially increases the maximum energy product (BH)max up to 20 MG Oe, remanence Br over 9 kG, and decreases intrinsic coercive force iHc. The addition of Si also increases Curie temperature and decreases reversible temperature coefficient. The combined addition of Si and Al spreads wheel surface velocity ranges to obtain (BH)max〉15 MG Oe and Br〉9 kG compared to the addition of Si only. The origin of high performance is discussed.

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1089-7623

AIP Digital Archive

Physics

Electrical Engineering, Measurement and Control Technology

Since 1994 at the National Institute of Radiological Sciences HIMAC, the NIRS Penning ionized-gauge ion source (PIGIS) has so far been used for radiotherapy with carbon beams and for basic research with several ion species. The source can produce beams from H2 to Fe with a charge-to-mass ratio of between 1/7 and 1/2. It is a hot-cathode type with a filament, of which the lifetime is on the order of a week and the cathode on the order of 1 month, under a low-duty pulsed operation (≤0.5%) synchronized to the ring operation. This PIGIS can produce highly charged ions: for example, 1 e mA of Ar7+ or 500 eμ A of Si5+ ions (by sputtering) under the typical arc power of 5 kW in peak. This article describes the present status of the NIRS-PIGIS. © 2000 American Institute of Physics.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Interleukin-4 (IL-4) may play a central role in the IgE synthesis system, the development of Th-2-like cells, and co-ordination as well as the persistence of airway inflammatory process in allergic disorders. Therefore, IL-4 plays a key role in airway allergic disorders. This study aimed at investigating the serum concentrations of IL-4 in patients with perennial allergic rhinitis, with special reference to the possible changes and the clinical relevance following long-term immunotherapy. The study has demonstrated that the serum level of IL-4 in allergic rhinitis patients before immunotherapy is significantly higher than that in non-atopic individuals. However, the serum IL-4 level in allergic rhinitis patients did not decrease following anti-allergic medications but significantly decreased following immunotherapy. The percentage decrease in IL-4 was correlated significantly with the percentage decrease in specific IgE antibodies following long-term immunotherapy. Immunotherapy also significantly decreased specific IgE antibodies, but this reduction in specific IgE antibodies was not significantly correlated with the clinical improvement. In contrast, the percentage decrease in serum IL-4 was significantly correlated with the percentage decrease in symptomatic scores. The authors interpret these data to mean that immunotherapy alters T-cell cytokine profiles in the long-term, and a decline of IL-4 following immunotherapy could modulate not only production of specific IgE antibodies but also inflammatory cellular events, leading to symptomatic relief in allergic rhinitis.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The rate of release of the soluble form of interleukin-2 receptor (soluble IL-2R) reflects T cell activation in vivo. Since T lymphocytes play a central role in respiratory allergic disorders, the measurement of serum levels of soluble IL-2R may be useful in analysing the disease state of allergic disorders. The study has aimed at investigating the seasonal changes in serum soluble IL-2R in 81 patients with seasonal allergic rhinitis due to Japanese cedar pollens, with special reference to the effect of anti-allergic pharmacotherapy and immunotherapy. Serum samples were obtained twice from each patient, before and during the pollen season, and all the serum samples were simultaneously used for determination of soluble IL-2R and cedar pollen-specific immunoglobin E (IgE). Seasonal elevation in soluble IL-2R was not associated with the good clinical outcome but was associated with the poor clinical outcome, irrespective of pharmacotherapy or immunotherapy. Additionally, successful immunotherapy suppressed seasonal elevation of serum soluble IL-2R more strongly than successful pharmacotherapy, and seasonal increase rates in soluble IL-2R were inversely correlated with the duration of immunotherapy. Seasonal increase rates in soluble IL-2R were significantly correlated with seasonal increase rates in specific IgE in both the medication group and the immunotherapy patients. These results may suggest that seasonal changes in serum soluble IL-2R may serve as an indicator for clinical outcome of seasonal allergic rhinitis, that the magnitude of T cell activation could affect specific IgE production, and that T cell activation could be gradually modulated as immunotherapy proceeds. In conclusion, seasonal changes in serum soluble IL-2R may serve as an objective indicator for clinical outcome of seasonal allergic rhinitis.

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

This study was designed to determine seasonal changes in cytokines, soluble CD23 and specific IgE in the serum of patients with seasonal allergic rhinitis, and the effect of immunotherapy on these seasonal changes. Fifty-four patients with seasonal allergic rhinitis caused by Japanese cedar pollens were divided into a medication group and an immunotherapy group. The patients of the medication group were treated with non-sedating antihistamines alone during the pollen season. The patients of the immunotherapy group had been treated for variable periods (mean, 5.0 ± 3.2 years) with immunotherapy using Japanese cedar pollen antigens. Serum samples were collected before and during the pollen season from each patient, to determine specific IgE, interleukin-4 (IL-4), interferon-γ (IFN-γ) and soluble CD23 levels in serum. A significant increase in specific IgE and IL-4 and a significant decrease in IFN-γ were observed during the pollen season in the medication group. In contrast, in the immunotherapy group, none of specific IgE, IL-4 and IFN-γ was significantly changed following natural exposure to pollens. However, these effects were not significant in patients undergoing immunotherapy for 3 or fewer years. Seasonal rates of increase in specific IgE and IL-4 differed significantly between good responders and poor responders to immunotherapy, but seasonal rates of decrease in IFN-γ did not. A seasonal rate of increase in soluble CD23 was significantly correlated with a seasonal rate of increase in specific IgE, in both the medication and the immunotherapy groups. The seasonal rate of increase in soluble CD23 was significantly smaller in the good responders than in the poor responders to immunotherapy. In conclusion, pollen immunotherapy reduces the seasonal increase in specific IgE, IL-4 and soluble CD23 in serum, and in addition switches the seasonal preferential activation of Th-2 cells to reciprocal activation of Th-1 cells with treatment over several years. It is likely that the mechanisms responsible for the clinically beneficial effects of immunotherapy principally involve the modulation of Th-2 rather than Th-1 cytokines.

Electronic Resource

1460-9568

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

A direct action of μ-opioid agonists on neurons in the spinal dorsal horn is thought to contribute to opiate-induced analgesia. In this study we have investigated neurons that express the μ-opioid receptor MOR-1 in rat spinal cord to provide further evidence about their role in nociceptive processing. MOR-1-immunoreactive cells were largely restricted to lamina II, where they comprised approximately 10% of the neuronal population. The cells received few contacts from nonpeptidergic unmyelinated afferents, but many from substance P-containing afferents. However, electron microscopy revealed that most of these contacts were not associated with synapses. None of the MOR-1 cells in lamina II expressed the neurokinin 1 receptor; however, the μ-selective opioid peptide endomorphin-2 was present in the majority (62–82%) of substance P axons that contacted them.    Noxious thermal stimulation of the foot induced c-Fos expression in approximately 15% of MOR-1 cells in the medial third of the ipsilateral dorsal horn at mid-lumbar level. However, following pinching of the foot or intraplantar injection of formalin very few MOR-1 cells expressed c-Fos, and for intraplantar formalin injection this result was not altered significantly by pretreatment with systemic naloxone.    Although these findings indicate that at least some of the neurons in lamina II with MOR-1 are activated by noxious thermal stimulation, the results do not support the hypothesis that the cells have a role in transmitting nociceptive information following acute mechanical or chemical noxious stimuli.

Electronic Resource

1471-4159

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract: An exchange assay is described for the measurement of nuclear estrogen receptors (ERn) in micro-dissected brain regions. The distribution of ERn in the hypothalamus and amygdala of the rat 1 h after an injection of estradiol (E) is presented. Combining the exchange assay with a previously described method for measurement of cytosol estrogen receptors (ERc) in microdissected brain samples, gonadectomized male and female rats were compared for ERc and ERn. While ERc concentrations tended to be higher in females than in males in all regions of the hypothalamus, with a significant sex difference in the arcuate-median eminence, no sex difference in ERn concentrations was observed after E injection. These results suggest that ERc measurements alone are not sufficient to establish the capacity of the E receptor system: ERn measurements are also necessary to establish the relationship between receptor levels and physiologic estrogen responsiveness.

Electronic Resource

1750-3841

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Process Engineering, Biotechnology, Nutrition Technology

Several suspensions and emulsions containing commercial sodium caseinate or skim milk were gelatinized by Ca2+-independent microbial transglutaminase treatment. The characteristics of the gels were largely affected by the enzyme concentrations employed. For caseinate gels generally the higher enzyme concentration gave steep decreases in breaking strength, strain and cohesiveness of the gels. The creep tests on emulsified gels prepared to two different enzyme concentrations showed that the gel made with a higher enzyme concentration was the more viscoelastic. For skim milk gels, the enzyme treatment in higher concentration caused substantial increase of the breaking and hardness while the strain and cohesiveness had little or no changes.

Electronic Resource

1440-1797

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1440-1797

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1440-1797

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1440-1797

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

This study was undertaken to clarify prognostic indices of a long-term clinical course in IgA nephropathy in large series.〈section xml:id="abs1-1"〉〈title type="main"〉PATIENTSFrom 1972 to 1990, a total of 603 patients were diagnosed to have primary IgA nephropathy in our renal unit. Of these patients 366 patients were continuously followed up for 10 years or more. These patients were the subjects of this study.〈section xml:id="abs1-2"〉〈title type="main"〉METHODSAs predictive factors, several parameters were evaluated as follows: initial proteinuria; initial creatinine clearance (Ccr) values; initial hypertension; histological severity (eight parameters and total score); % duration of massive proteinuria (%DP); % duration of hypertension (%DH). %DP was defined as [(duration of proteinuria of 1.0g/day or more ÷ total duration of follow-up observation) × 100]. %DH was defined as [duration of hypertension ÷ total duration of follow-up observation] × 100].As histological severity, eight parameters were evaluated according to the semiquantitative method of Pirani et al. Each of these lesions was graded from 0 to 3. A total score was defined as a total of all eight scores, graded from 0 to 24.During the 10-year follow-up observation, corticosteroid treatment was conducted in 112 patients. Most of the patients received antiplatelet drugs. Hypertensive patients were treated with antihypertensive therapy.Final outcome at 10 years since the initial renal biopsy was divided into three clinical courses as follows: a stable course was defined as no decrease of renal function for 10 years; a progressive course was defined as a decrease of 15% or more of initial Ccr values without going into HD; and haemodialysis (HD).Univariate analysis for these predictive factors was performed by using one-factor ANOVA corrected by Bonferroni/Dunn or Kruskal-Wallis test to determine the final outcome. A multivariate analysis was done by using a logistic model.〈section xml:id="abs1-3"〉〈title type="main"〉RESULTSThe age of the 366 patients was 33 ± 10 (range: 13–61); gender (M/F) 181/185; initial proteinuria 1.0 ± 1.0g/day (range: 0–6.6); initial Ccr values 85 ± 21 mL/min (range: 25–139); initial hypertension 63 cases (17%); total score as histological severity 7.7 ± 4.6.The final proteinuria was 0.9 ± 1.0 g/day (range: 0–5.7); final Ccr values 58 ± 38 mL/min (0–128); final hypertension 94 cases (25%); %DP 33 ± 39; %DH 18 ± 30. Numbers of patients having a stable course, a progressive course and haemodialysis were 192 (52%), 89 (25%) and 85 (23%), respectively.Clinical prognostic indices showed significant differences in age, initial proteinuria, initial Ccr, initial hypertension, %DO and %DH, respectively (P 〈 0.0001). Treatment with corticosteroids was significantly frequent in progressive and haemodialysis groups than a stable group (P 〈 0.0003).Histological prognostic indices showed significant differences in hypercellularity, active crescent, tuft adhesion, mesangial sclerosis, global sclerosis, tubular atrophy, interstitial fibrosis, vascular sclerosis and total score (P 〈 0.005).Multivariate analysis of clinical prognostic indices showed the highest relevance in %DP (relative risk 32.9, P 〈 0.0001), followed by %DH (relative risk 14.2, P 〈 0.0001).Multivariate analysis of histological prognostic indices showed the highest relevance in tubular atrophy (relative risk 9.2, P 〈 0.002), followed by interstitial fibrosis (relative risk 3.0, P 〈 0.05).Multivariate analysis of clinicohistological indices showed the highest relevance in %DP (relative risk 38.0, P 〈 0.0001), followed by %DH (relative risk 18.7, P 〈 0.0001).Patients with 30% or less in %DP underwent a favourable clinical course, while patients with 40% or more had a poor prognosis.%DH was one of the most reliable prognostic indices. However, there was no evidence of a turning point determining a long-term prognosis.〈section xml:id="abs1-4"〉〈title type="main"〉COMMENTThirty-three years have passed since IgA nephropathy was first reported in 1968. Many investigations have documented a long-term prognosis of the disease and predictive factors for a long-term clinical course. It is generally accepted that the renal survival rate of the disease is recognized to be 70–80% 10 to 20 years after clinical onset. Clinically, initial proteinuria and initial renal function are well related with a long-term prognosis. Histologically, interstitial fibrosis is a most reliable predictive factor for a poor prognosis as well. However, there are few reports evaluated by a large series with a long-term follow-up observation.In this study, all 366 patients have been continuously followed up for 10 years since the first renal biopsy. About 50% of the patients underwent a progressive course, with 25% of the total patients entering into chronic haemodialysis. Multivariate analyses of clinical and histological predictors at the time of the first renal biopsy indicated that not only initial proteinuria and initial renal function but also tubular atrophy and interstitial fibrosis are very important factors, as reported previously.However, in practical clinical observation, it is difficult to predict a long-term prognosis merely at the time of renal biopsy. Therefore, careful follow-up observation is needed to evaluate the disease activity.In the present study, the continuous examination of daily urinary protein excretion and blood pressure was performed during a follow-up period of 10 years. As the result, %DP of 1.0 g/day or more is clarified to be the most reliable independent predictor for a long-term prognosis, followed by %DH. Moreover, 40% or more of %DP is found to be well related with a poor prognosis.In conclusion, the most reliable, independent factor determining a long-term prognosis in IgA nephropathy is persistent massive proteinuria of 1.0 g/day or more.

Electronic Resource

1440-1797

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

IgA nephropathy (IgAN) is known to commonly cause of end-stage renal failure in Japan. The glomerular lesions of IgAN have histological variations. The determination of prognosis and therapeutic strategy should be carefully done by experts because morphological information from renal biopsies using ordinary optical microscopy is usually qualitative and subjective. Moreover, the histological items for the evaluation of glomerular lesions seems to be unsatisfactory for expression of the disease condition of IgAN. The beneficial properties of scanning acoustic microscopy (SAM) include not only observation of microstructure but also quantitative measurement of acoustic propagation speed (APS), indicating the tissue elasticity. In the present study we compared the APS of glomeruli with the pathological scores that were determined by ordinary light microscopy. We used stocked human renal biopsy specimens diagnosed as IgAN (n = 12) and normal/minimal changes (n = 5). All samples were taken by renal biopsy in Kagawa Medical University Hospital during 1997–2000 under informed consent of the patients. The obtained renal tissue were immersed in 10% formalin and embedded in paraffin. A fixed specimen was consecutively cut into 4 μm slices. One of the deparaffinized 4 μm-specimens was directly utilized for SAM without any staining, and the others were stained with haematoxylin-eosin and Masson Trichrome for counting cell number and evaluation of collagen accumulation. For the measurement of glomerular APS, the sample line was set on the equator of the glomerulus and then scanning of the X–Z axis was carried out to obtain the interference fringes that were analysed with a computer imaging software in order to calculate the APS. In light microscopic study, pathological scores were evaluated semiquantitatively by two independent investigators who were unaware of the sample number. Glomerular lesions were scored into five grades and glomerular cell number was also counted in individual glomerulus. The computer-assisted imaging analyser Win ROOF (Mitani, Fukui, Japan) was also used for the determination of glomerular collagen content in specimens stained by Masson Trichrome. A two-dimensional image (C-mode scanning) of SAM enabled imaging of glomerulus in renal biopsy specimen compatible with findings of ordinary light microscopy without staining dye. The glomerular APS in IgAN was significantly higher than in normal/minimal changes. This alteration of glomerular APS in IgAN was positively correlated to both semiquantitative pathological scores and glomerular collagen content determined by light microscopy. However, the cell number of glomelurus did not change between IgAN and normal/minimal change. As a result, we conclude that the glomerular lesion, especially matrix expansion in IgAN, was comparable with the absolute value among specimens. Therefore, it is suggested that SAM method is a novel and useful technique for quantitative evaluation of glomerular lesion in IgAN.

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