90 research outputs found
Asymmetrical membrane fluidity of bovine adrenal chromaffin cells and granules and effect of trichosporin-B-VIa
AbstractWe examined membrane fluidity of bovine adrenal chromaffin cells and chromaffin granules using cationic trimethylammonium derivative of diphenylhexatriene (TMA-DPH) as a fluorescence probe. After adding TMA-DPH to the suspension of chromaffin cells and that of granules, it first bound to the outer layer of the plasma membrane of the cells and that of the granule membrane, then gradually penetrated the inner layer of each membrane and distributed to both leaflets of the respective membranes. Accompanying increases in the ratio of incorporated probe on the cytoplasmic side of the chromaffin cell membrane, its fluorescence anisotropy gradually decreased. However, in chromaffin granules, the fluorescence anisotropy gradually increased with increases in the ratio of incorporated probe. These findings suggest that the inner layer of the plasma membrane and outer layer of the granular membrane are more fluid than the corresponding side of each membrane, which is suitable for the fusion between both membranes. We also examined the effect of trichosporin-B-VIa, a fungal ion channel forming α-aminoisobutyric acid-containing peptide, on the fluidity of chromaffin cells using TMA-DPH. The peptide decreased the fluorescence anisotropy and increased the fluorescence intensity in the concentration range that induced Ca2+ dependent catecholamine secretion, suggesting that a change in lipid dynamics of the lipid bilayer of the plasma membrane was induced by this peptide
Validity of Dietary Surveys in Physically Active Japanese Male Students
Under or overestimating dietary intake is considered a serious problem in dietary surveys. We compared estimated energy intake (EI) with measured total energy expenditure (TEE) in 22 physically active Japanese male students (age: 20.6±1.2 years: active group) and 37 physically non-active male students (age: 19.3±1.4 years: control group). EI was estimated by a food frequency questionnaire (FFQg). TEE was calculated by using the time study method with a measured basal metabolic rate. The accuracy of EI (EI/TEE) was 0.57 in the active group and 0.74 in the control group; showing a significant difference between the two groups (p<0.01). EI/TEE was negatively associated (r=-0.395, p<0.05) with BMI in the control group, but not in the active group. Intake of confectioneries, oils and fruits in the active group was significantly higher (p<0.01, p<0.05, p<0.01 respectively) than the control group. Intake of confectioneries and fruits per 1,000kcal was significantly higher (p<0.05, p<0.01 respectively) but grains were significantly lower (p<0.01) in the active group than the control group. EI/TEE was positively associated (r=0.539, p<0.05) with intake of fish per 1,000kcal in the active group. These results suggested that underestimating dietary intake might occur more often among physically active male students than physically inactive male students and it seemed to be associated with their lack of interest in food rather than psychological factors
Quantitative study of near equilibrium in dissociative mechanism of nickel in silicon
The dissociative mechanism of nickel in silicon has been studied experimentally, assuming the near equilibrium represented by
CiCV / Cs = Ci eq C eq / Cs eq , where subscripts i, V, and s represent interstitial nickel atoms, vacancies, and substitutional nickel
atoms, respectively, superscript eq represents the thermal equilibrium, and CA is the concentration of component A. However, the assumption of the near equilibrium has not yet been verified experimentally, because it is difficult to measure CV in silicon. In the present work, the simultaneous diffusion equations of the dissociative mechanism of nickel in silicon are solved numerically by
double-precision FORTRAN without assuming the near equilibrium under the condition of in-diffusion of nickel into a silicon specimen, and the establishment of the near equilibrium is verified. It is also clarified that the near equilibrium is a transitional process which continues until the thermal equilibrium is reached. After the near equilibrium is reached, the very small difference of two nearly equal terms is an important factor in solving the diffusion equations. In other words, high accuracy is necessary to solve the diffusion equations. Concerning this, it is verified that the accuracy of double-precision FORTRAN is sufficiently high to solve the diffusion equations in the present work
Identifying dynamical systems with bifurcations from noisy partial observation
Dynamical systems are used to model a variety of phenomena in which the
bifurcation structure is a fundamental characteristic. Here we propose a
statistical machine-learning approach to derive lowdimensional models that
automatically integrate information in noisy time-series data from partial
observations. The method is tested using artificial data generated from two
cell-cycle control system models that exhibit different bifurcations, and the
learned systems are shown to robustly inherit the bifurcation structure.Comment: 16 pages, 6 figure
The vasopressin V1b receptor critically regulates hypothalamic-pituitary-adrenal axis activity under both stress and resting conditions
Optical and Near-Infrared Photometry of Nova V2362 Cyg : Rebrightening Event and Dust Formation
We present optical and near-infrared (NIR) photometry of a classical nova,
V2362 Cyg (= Nova Cygni 2006). V2362 Cyg experienced a peculiar rebrightening
with a long duration from 100 to 240 d after the maximum of the nova. Our
multicolor observation indicates an emergence of a pseudophotosphere with an
effective temperature of 9000 K at the rebrightening maximum. After the
rebrightening maximum, the object showed a slow fading homogeneously in all of
the used bands for one week. This implies that the fading just after the
rebrightening maximum ( less or equal 1 week ) was caused by a slowly shrinking
pseudophotosphere. Then, the NIR flux drastically increased, while the optical
flux steeply declined. The optical and NIR flux was consistent with blackbody
radiation with a temperature of 1500 K during this NIR rising phase. These
facts are likely to be explained by dust formation in the nova ejecta. Assuming
an optically thin case, we estimate the dust mass of 10^(-8) -- 10^(-10)
M_solar, which is less than those in typical dust-forming novae. These results
support the senario that a second, long-lasting outflow, which caused the
rebrightening, interacted with a fraction of the initial outflow and formed
dust grains.Comment: 6 pages, 4 figures, 2010, PASJ, 62, 1103--1108, in pres
The 2006 November outburst of EG Aquarii: the SU UMa nature revealed
We report time-resolved CCD photometry of the cataclysmic variable EG Aquarii
during the 2006 November outburst During the outburst, superhumps were
unambiguously detected with a mean period of 0.078828(6) days, firstly
classifying the object as an SU UMa-type dwarf nova. It also turned out that
the outburst contained a precursor. At the end of the precursor, immature
profiles of humps were observed. By a phase analysis of these humps, we
interpreted the features as superhumps. This is the second example that the
superhumps were shown during a precursor. Near the maximum stage of the
outburst, we discovered an abrupt shift of the superhump period by
0.002 days. After the supermaximum, the superhump period decreased at the rate
of =, which is typical for SU UMa-type dwarf
novae. Although the outburst light curve was characteristic of SU UMa-type
dwarf novae, long-term monitoring of the variable shows no outbursts over the
past decade. We note on the basic properties of long period and inactive SU
UMa-type dwarf novae.Comment: 9 pages, 7 figures, accepted for PAS
Construction of a T cell receptor signaling range for spontaneous development of autoimmune disease
マッショウ タンカクキュウ サイボウ オ モチイタ マッショウ ドウミャク ヘイソクショウ ニ タイスル アラタナ ケッカン シンセイ リョウホウ ノ ココロミ
Earlier studies have shown that bone marrow-derived mononuclear cell(BM-MNC)implantation induces therapeutic angiogenesis in patients with peripheral arterial disease(PAD). However, the invasiveness of bone marrow collection limits clinical application of BM-MNC implantation.We performed peripheral blood-derived mononuclear cell(PB-MNC)implantation in ischemic limbs of five patients with PAD. After implantation, clinical symptoms such as rest pain and numbness were relieved in four patients. Maximal walking distance markedly increased from 160 m to 915 m in one patient. Non-healing ulcers were cured after repeated cell implantation in one patient with Burger disease. There was no adverse event. These findings suggest that PB-MNC implantation is a safe and noninvasive strategy for therapeutic angiogenesis for the treatment of severe PAD
JPN Guidelines for the management of acute pancreatitis: severity assessment of acute pancreatitis
This article addresses the criteria for severity assessment and the severity scoring system of the Ministry of Health and Welfare of Japan; now the Japanese Ministry of Health, Labour, and Welfare (the JPN score). It also presents data comparing the JPN score with the Acute Physiology and Chronic Health Evaluation (APACHE) II score and the Ranson score, which are the major measuring scales used in the United States and Europe. The goal of investigating these scoring systems is the achievement of earlier diagnosis and more appropriate and successful treatment of severe or moderate acute pancreatitis, which has a high mortality rate. This article makes the following recommendations in terms of assessing the severity of acute pancreatitis
- …