鉛直下向き揚力を発生する没水翼の造波現象に関する研究

研究期間:平成6-7年度 ; 研究種目:一般研究B ; 課題番号: 0645235

Efficacy of the Pulse Pressure Generator during Cardiopulmonary Bypass Training Using the Extracorporeal Circulation Simulator

Objective: Cardiopulmonary bypass during cardiac surgery is an essential procedure, and the perfusionist needs to have sufficient education and training. Simulation training is suitable in such cases. We have developed a simulation system for cardiopulmonary bypass training (extracorporeal circulation simulator [ECCSIM]) and reported its efficacy. ECCSIM had no pulse pressure generator, so some perfusionists have mentioned that the operational feeling during training differs from that in real clinical cases. In this study, we have developed a new pulse pressure generator and examined the efficacy of this system during cardiopulmonary bypass training using ECCSIM. Materials and Methods: Results were observed as wave patterns during simulation of extracorporeal circulation with and without pulse pressure flow. Operational feeling during training of extracorporeal circulation was compared using a questionnaire survey, based on the Japanese version of the NASA Task Load Index (NASA-TLX), a subjective index, completed by seven perfusionists. Results: With the addition of pulse pressure flow, fluctuation of arterial flow at low speed with the centrifugal pump increased, and operation of extracorporeal circulation became unstable. The questionnaire survey, including ‘Operational feeling of centrifugal pump’, ‘Feeling of afterload’, and ‘Display of pressure monitor’, showed results similar to that of the clinical situation using pulse pressure flow. The difficulty of simulator operation in extracorporeal circulation was significantly greater in the group with pulse pressure flow. Mental/physical load examined with NASA-TLX increased with pulse pressure flow. Conclusion: Using a new pulse pressure generator with ECCSIM was effective in extracorporeal circulation training

Thiamine tetrahydrofurfuryl disulfide promotes voluntary activity through dopaminergic activation in the medial prefrontal cortex

A physically active lifestyle is associated with better health in body and mind, and it is urgent that supporting agents for such lifestyles be developed. In rodents, voluntary locomotor activity as an active physical behavior may be mediated by dopaminergic neurons (DNs). Thiamine phosphate esters can stimulate DNs, and we thus hypothesized that thiamine tetrahydrofurfuryl disulfide (TTFD), a thiamine derivative, promotes locomotor activity via DNs in rats. Acute i.p. administration of TTFD enhanced rat locomotor activity in a normal cage. In vivo microdialysis revealed that TTFD-enhanced locomotor activity was synchronized with dopamine release in the medial prefrontal cortex (mPFC). Antagonism of the dopamine D1 receptor, but not D2 receptor, in the mPFC fully suppressed TTFD-enhanced locomotor activity. Finally, we found a TTFD dose-dependent increase in voluntary wheel running. Our findings demonstrate that DNs in the mPFC mediates TTFD-enhanced locomotor activity, suggesting the potential of TTFD to induce active physical behavior

Supranormal orientation selectivity of visual neurons in orientation-restricted animals

Altered sensory experience in early life often leads to remarkable adaptations so that humans and animals can make the best use of the available information in a particular environment. By restricting visual input to a limited range of orientations in young animals, this investigation shows that stimulus selectivity, e.g., the sharpness of tuning of single neurons in the primary visual cortex, is modified to match a particular environment. Specifically, neurons tuned to an experienced orientation in orientation-restricted animals show sharper orientation tuning than neurons in normal animals, whereas the opposite was true for neurons tuned to non-experienced orientations. This sharpened tuning appears to be due to elongated receptive fields. Our results demonstrate that restricted sensory experiences can sculpt the supranormal functions of single neurons tailored for a particular environment. The above findings, in addition to the minimal population response to orientations close to the experienced one, agree with the predictions of a sparse coding hypothesis in which information is represented efficiently by a small number of activated neurons. This suggests that early brain areas adopt an efficient strategy for coding information even when animals are raised in a severely limited visual environment where sensory inputs have an unnatural statistical structure

Characterization of the novel mutant A78T-HERG from a long QT syndrome type 2 patient: Instability of the mutant protein and stabilization by heat shock factor 1

Background:The human ether-a-go-go-related gene (HERG) encodes the α-subunit of rapidly activating delayed-rectifier potassium channels. Mutations in this gene cause long QT syndrome type 2 (LQT2). In most cases, mutations reduce the stability of the channel protein, which can be restored by heat shock (HS). Methods: We identified the novel mutant A78T-HERG in a patient with LQT2. The purpose of the current study was to characterize this mutant protein and test whether HS and heat shock factors (HSFs) could stabilize the mutant protein. A78T-HERG and wild-type HERG (WT-HERG) were expressed in HEK293 cells and analyzed by immunoblotting, immunoprecipitation, immunofluorescence, and whole-cell patch clamping. Results: When expressed in HEK293 cells, WT-HERG gave rise to immature and mature forms of the protein at 135 and 155 kDa, respectively. A78T-HERG gave rise only to the immature form, which was heavily ubiquitinated. The proteasome inhibitor MG132 increased the expression of immature A78T-HERG and increased both the immature and mature forms of WT-HERG. WT-HERG, but not A78T-HERG, was expressed on the plasma membrane. In whole-cell patch clamping experiments, depolarizing pulses evoked E4031-sensitive HERG channel currents in cells transfected with WT-HERG, but not in cells transfected with A78T-HERG. The A78V mutant, but not A78G mutant, remained in the immature form similarly to A78T. Maturation of the A78T-HERG protein was facilitated by HS, expression of HSF-1, or exposure to geranyl geranyl acetone. Conclusions: A78T-HERG was characterized by protein instability and reduced expression on the plasma membrane. The stability of the mutant was partially restored by HSF-1, indicating that HSF-1 is a target for the treatment for LQT2 caused by the A78T mutation in HERG

商業スポーツクラブ会員の選好行動に関する研究 : 入会意思決定過程における消費者選好について

The purpose of this study is to examine consumer preferences for services of commercial sport clubs. This study developed a consumer behavior (preference) model which is intended to explain the choice decision making process. Data for this study were collected in an urban commercial sport club located in Osaka. A sample of 198 club members was studied through computer interactive interviewing. Fourteen service attributes were considered in evaluating the sport club services. These preference items were separately analyzed by groups of club members segmented on the basis of gender and marital status, and withdrawal experiences of other sport clubs. The findings of this study are as follows : Service attributes such as distance and cleanliness were more influential factors in consumer preferences for the commercial sport clubs. Female club members take many service attributes into consideration when they choose among alternative sport clubs. Club members who have withdrawal experiences from other sport clubs were less concerned with business hours than other club members. These results are useful for the management of commercial sport clubs

Predictive factors of mortality of patients with fragility hip fractures at 1 year after discharge : A multicenter, retrospective study in the northern Kyushu district of Japan

Purpose: Fragility hip fractures (FHFs) are associated with a high risk of mortality, but the relative contribution of various factors remains controversial. This study aimed to evaluate predictive factors of mortality at 1 year after discharge in Japan. Methods: A total of 497 patients aged 60 years or older who sustained FHFs during follow-up were included in this study. Expected variables were finally assessed using multivariable Cox proportional hazards models. Results: The 1-year mortality rate was 9.1% (95% confidence interval: 6.8–12.0%, n = 45). Log-rank test revealed that previous fractures (p = 0.003), Barthel index (BI) at discharge (p = 0.011), and place-to-discharge (p = 0.004) were significantly associated with mortality for male patients. Meanwhile, body mass index (BMI; p = 0.023), total Charlson comorbidity index (TCCI; p = 0.005), smoking (p = 0.007), length of hospital stay (LOS; p = 0.009), and BI (p = 0.004) were the counterparts for females. By multivariate analyses, previous vertebral fractures (hazard ratio (HR) 3.33; p = 0.044), and BI <30 (HR 5.42, p = 0.013) were the predictive variables of mortality for male patients. BMI <18.5 kg/m2 (HR 2.70, p = 0.023), TCCI ≥5 (HR 2.61, p = 0.032), smoking history (HR 3.59, p = 0.018), LOS <14 days (HR 13.9; p = 0.007), and BI <30 (HR 2.76; p = 0.049) were the counterparts for females. Conclusions: Previous vertebral fractures and BI <30 were the predictive variables of mortality for male patients, and BMI <18.5 kg/m2, TCCI ≥5, smoking history, LOS <14 days, and BI <30 were those for females. Decreased BI is one of the independent and preventable risk factors. A comprehensive therapeutic approach should be considered to prevent deterioration of activities of daily living and a higher risk of mortality

シミュレーションによる商業スポーツクラブの選好シェア予測

The purpose of this paper is to examine sports market via applying conjoint analysis to commercial sports club services. A simulation model was used to predict fluctuations in sports club market share. Data for this study were collected from an urban commercial sports club located in Osaka. A sample of 198 club members was studied through computer interactive interviewing. Six service attributes and 18 levels were considered in the research design. Service profiles that were combinations of attributes and levels were presented to respondents by means of paired comparisons. The overall ranked data were analyzed using Jonhson\u27s nonmetric tradeoff algorithm. Conjoint analysis allows the researcher to determine consumer\u27s part-worth utilities for each service attribute under study. Conjoint choice simulator requires part-worth utility information to predict which set of competing attribute profiles individuals are likely to choose. The first choice model was used as the choice simulator in this study. Findings from the simulation were as follows : 1) Extension of the market share was caused by improvements in conditions such as \u27distance\u27, \u27monthly fee\u27, and \u27augumented facilities\u27. 2) Reduction in market share was caused by a decline in \u27instractor quality\u27, \u27distance\u27, \u27membership initiation fee\u27, and \u27monthly fee\u27 conditions. 3) A sports club without any distinctive service attributes was not chosen by consumers. These results that management should characterize the sports club as having specific service attributes

Blood Pressure and Arterial Stiffness

Background—The difference in the predictive ability of the brachial-ankle pulse wave velocity (baPWV) and its stiffness index β-transformed value (β-baPWV, ie, baPWV adjusted for the pulse pressure) for the development of pathophysiological abnormalities related to cardiovascular disease or future occurrence of cardiovascular disease was examined. Methods and Results—In study 1, a 7-year prospective observational study in cohorts of 3274 men and 3490 men, the area under the curve in the receiver operator characteristic curve analysis was higher for baPWV than for β-baPWV for predicting the development of hypertension (0.73, 95% CI=0.70 to 0.75 versus 0.59, 95% CI=0.56 to 0.62; P<0.01) and/or the development of retinopathy (0.78, 95% CI=0.73 to 0.82 versus 0.66, 95% CI=0.60 to 0.71; P<0.01) by the end of the study period. During study 2, a 3-year observation period on 511 patients with coronary artery disease, 72 cardiovascular events were confirmed. The C statistics of both markers for predicting the development of cardiovascular events were similar. Conclusions—Stiffness index β transformation of the baPWV may attenuate the significance of the baPWV as a risk marker for development of pathophysiological abnormalities related to cardiovascular disease in male subjects

DNA Methylation and Normal Chromosome Behavior in Neurospora Depend on Five Components of a Histone Methyltransferase Complex, DCDC

Methylation of DNA and of Lysine 9 on histone H3 (H3K9) is associated with gene silencing in many animals, plants, and fungi. In Neurospora crassa, methylation of H3K9 by DIM-5 directs cytosine methylation by recruiting a complex containing Heterochromatin Protein-1 (HP1) and the DIM-2 DNA methyltransferase. We report genetic, proteomic, and biochemical investigations into how DIM-5 is controlled. These studies revealed DCDC, a previously unknown protein complex including DIM-5, DIM-7, DIM-9, CUL4, and DDB1. Components of DCDC are required for H3K9me3, proper chromosome segregation, and DNA methylation. DCDC-defective strains, but not HP1-defective strains, are hypersensitive to MMS, revealing an HP1-independent function of H3K9 methylation. In addition to DDB1, DIM-7, and the WD40 domain protein DIM-9, other presumptive DCAFs (DDB1/CUL4 associated factors) co-purified with CUL4, suggesting that CUL4/DDB1 forms multiple complexes with distinct functions. This conclusion was supported by results of drug sensitivity tests. CUL4, DDB1, and DIM-9 are not required for localization of DIM-5 to incipient heterochromatin domains, indicating that recruitment of DIM-5 to chromatin is not sufficient to direct H3K9me3. DIM-7 is required for DIM-5 localization and mediates interaction of DIM-5 with DDB1/CUL4 through DIM-9. These data support a two-step mechanism for H3K9 methylation in Neurospora