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The evaluation of temporal and spatial fluctuations of energy using compressible fluid analysis is proposed as an effective method to clarify the fundamental mechanism of the self-sustained oscilla-tions in a actual recorder. The main factors of the self-sustained oscillations are investigated in more detail by evaluating not only the steady state of the sound where the flow field and the sound field are completely coupled, but also the characteristics at the attack transient of the sound before the coupling is established. By analyzing the large energy fluctuations that occur just below the edge of the labium in the attack transient, it was shown that this phenomenon may be one of the main causes of the self-sustained oscillations. And the characteristics of the energy fluctuations and sound power generation during the steady state of the sound are discussed. It was also focused on the energy variations in another region that is near the exit of the windway.

A numerical simulation of a single-reed instrument with a pressure chamber is conducted to examine the interaction among the flow, reed oscillation, and acoustic propagation. The flow and acoustic fields are predicted using the three-dimensional compressible Navier-Stokes equations, whereas the one-dimensional dynamic beam equation is solved for reed oscillation. The deforming geometry in the aeroacoustic field is expressed by the volume penalization method as an immersed boundary technique. The results showed that the waveforms of the tip opening and far-field acoustic spectra agreed well with those measured experimentally. The three-dimensional flow configuration near the tip opening was visualized, and the measurement of the instantaneous volume flow rate at the tip opening revealed that 30%-40% of the total flow rate passed through the side opening. The spectral tendencies of the time derivatives of the flow rate for different tip openings were consistent with that of the far-field sound, indicating that the slope of the flow rate waveform significantly affects the generated sound's harmonics.

Aquaporins (AQPs) are a family of water-transporting proteins that are selectively expressed in epithelial, endothelial, and many other cell types of various tissues, where they play important physiological functions. However, the accurate distribution of AQP gene expression has not yet been examined in various tissues of the mouse. We first evaluated the tissue distribution of AQP gene expression using tongue, nasal epithelium, bronchus, trachea, lung, esophagus, stomach, ileum, transverse colon, liver, pancreas, whole blood, thigh muscle, spinal cord, brain, thoracic aorta, heart, kidney, thymus, spleen, skin, eye, and testis of the mouse. Furthermore, for a quantitative analysis, we selected appropriate reference genes for normalized qRT-PCR data in various tissues. The stability of the reference genes was assessed using NormFinder. The stably expressed genes identified in the present study were 18s rRNA. When 18s rRNA was used, as the best reference gene in the present study, the genes for AQPs 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, and 12 were notably expressed in the eye, lung, testis, eye, spinal cord, trachea, kidney, testis, testis, testis, testis, and pancreas. These results, regarding the distribution of AQPs, suggest that AQPs may be involved in various physiological and pathophysiological processes.

To clarify the effects of the windway geometry on the aeroacoustic feedback in the jet fluctuations in recorders, direct aeroacoustic simulations were performed along with experiments. The simulations were based on the compressible Navier-Stokes equations to predict the fluid-acoustic interactions. The volume penalization method was used to reproduce the flow and acoustic fields around the complex shape of the recorders. Two recorders with straight and arch-shaped windway were explored. The occurrence of mode change was observed at the higher velocity for an arch-shaped windway model compared with the straight windway model. The modified formulation of the negative displacement model (N.H. Fletcher et al., 1976, J. Acoust.) was proposed based on the predicted jet fluctuations, where the jet fluctuations were divided into hydrodynamic and acoustic components. The ratio of the hydrodynamic component to the acoustic component near the windway exit was lower in the archshaped windway model than that in the straight windway model, whereas the amplification factor of the jet fluctuations was larger in the arch-shaped windway model.The relevance of these results and the mode change along the jet velocity is to be discussed.To clarify the effects of the windway geometry on the aeroacoustic feedback in the jet fluctuations in recorders, direct aeroacoustic simulations were performed along with experiments. The simulations were based on the compressible Navier-Stokes equations to predict the fluid-acoustic interactions. The volume penalization method was used to reproduce the flow and acoustic fields around the complex shape of the recorders. Two recorders with straight and arch-shaped windway were explored. The occurrence of mode change was observed at the higher velocity for an arch-shaped windway model compared with the straight windway model. The modified formulation of the negative displacement model (N.H. Fletcher et al., 1976, J. Acoust.) was proposed based on the predicted jet fluctuations, where the jet fluctuations were divided into hydrodynamic and acoustic components. The ratio of the hydrodynamic component to the acoustic component near the windway exit was lower in the archshaped windway model than that in the st...

救急医療体制の確立とともに突然心停止し,心肺停止状態で救急医療施設に搬入されるCPAOA例が増加している。急性心筋梗塞発症早期に突然死が多いとされるが,入院前心停止例では正確な臨床診断は難しく,病理解剖でも発症6時間以内では特徴ある所見に乏しい。目的:成人内因性突然死における急性心筋梗塞の頻度と発症直後に突然心停止した心筋梗塞超急性期の病態を明らかにする。症例・方法:最近7年間に当部へ搬入された30～80歳の内因性CPAOA384例のうち臨床診断で「急性心不全」が212例(55.2%)を占めた。このうちの64例に剖検を行い,剖検時冠状動脈造影を含め冠状動脈ならびに心筋病変を検討した。急性心筋梗塞の診断は冠状動脈の血栓性閉塞・狭窄所見を重視し,病変灌流域心筋組織のhematoxylin-basic-fuchsin-picric acid染色陽性所見を参考とした。結果:64例中急性心筋梗塞は36例(56.3%)で,27例に内膜破綻と新鮮血栓,6例に内膜破綻がみられた。初発心筋梗塞19例,陳旧性梗塞再発例17例で,前者の6例,後者の12例が重症多枝病変例であった。冠状動脈閉塞・狭窄病変は主要冠状動脈中枢側に多かったが,とくに一枝病変例18例では各枝いずれも中枢側に責任病変があった。他は不整脈死6,大動脈瘤破裂6,心筋症4,肺塞栓症2,その他7,不明3例であった。考案・結語:「急性心不全」とされた成人内因性CPAOA64例の剖検で急性心筋梗塞が36例,56.3%を占めた。これを「急性心不全」212例にあてはめて推定した例に臨床診断で急性心筋梗塞と診断し得た20例を加えると成人内因性CPA症例384例中で急性心筋梗塞の頻度は36.2%と推定された。心筋梗塞超急性期突然死例のうち初回発症例では一枝病変例が,再発例では重症多枝病変例が多く,また一枝病変突然死例では各枝中枢側に病変を有することが示された。

A 63-year-old woman underwent surgical operations for left lower lung cancer and for thyroid cancer. Nine months later, a third cancer developed in her heart and this tumor was removed by open heart surgery. A pathologic study revealed that the tumor was primary leiomyosarcoma of the heart and thus independent from the previous lung and thyroid carcinomas. This case was regarded as a triple carcinoma including a primary leiomyosarcoma arising from the left atrium. Reports in the literature on primary malignant tumors of the heart are reviewed briefly.

Two patients presented with ampulla cardiomyopathy induced by meningitis. A 71-year-old man with meningitis was admitted to our neurosurgery division. Emergent coronary angiography was performed, because of sudden blood pressure fall and ST elevation in the precordial leads. Left ventriculography and coronary angiography revealed apical ballooning without coronary stenosis. A 73-year-old woman with meningitis was admitted to another hospital. She felt chest pain. Electrocardiography showed ST elevation in the precordial leads. She was transferred to our division. Echocardiography revealed apical ballooning and hyperkinesis of the base. Creatine kinase level showed no elevation on admission or 8 hr later. Ampulla cardiomyopathy with cerebrovascular disease is common, but rare with meningitis, which needs intensive care because of the risk of respiratory arrest.

The precise etiological basis of transient left ventricular apical ballooning without coronary artery stenosis (ampulla or so-called `takotsubo' cardiomyopathy) remains unknown, so the present study examined the acute effects of intravenous propranolol (2-4 mg) in 3 female patients (age range, 61-76 years) with the condition. Although one patient who did not have any intraventricular pressure gradients showed no improvement in the electrocardiographic and left ventricular wall motion abnormalities, the other 2 patients, who had significant intraventricular pressure gradients, did show improvement. Dynamic intraventricular obstruction might play a role in maintaining apical ballooning, at least, in patients exhibiting an intraventricular pressure gradient. (Circ J 2002; 66: 1181 - 1184)

Our results shows molecular markers, particularly TAT, is useful for early detection of thrombus formation in the false lumen in acute aortic dissection.

The distribution of sympathetic neurons within the canine left ventricle was assessed by measuring the myocardial uptake of [3H]norepinephrine in anesthetized dogs. The nonneuronal uptake of [3H]norepinephrine was also assessed in a separate group of cocaine-treated animals. The left ventricle was systematically divided into multiple sections. The [3H]norepinephrine was isolated in tissue homogenates, using alumina extraction, and quantified by liquid scintillation counting. The results revealed a nonuniform pattern of [3H]norepinephrine uptake in the ventricular free wall, with a greater uptake in the base than in the apex. Differences in uptake between the anterior and posterior regions of the free wall, and between the free wall and the septum were not statistically significant. In the cocainetreated animals uptake was approximately 20% of that in the control animals. Furthermore, there were no significant regional differences. These data suggest that in the canine left ventricle the sympatheti...

Many reports have suggested that cardiac dysfunction with cardiomegaly is more often observed in patients with chronic hemodialysis. Moreover, cardiac dysfunction has been thought as one of the most important factors affecting the prognosis of these patients. In this study, in order to clarify the role of l-carnitine in the pathogenesis of cardiomegaly, 33 patients with chronic hemodialysis were studied using the multivariate analysis method. Among the factors which may affect cardiac function, the following 10 variables were examined. 1) age, 2) duration of dialysis, 3) plasma carnitine, 4) serum total cholesterol, 5) serum HDL-cholesterol, 6) triglyceride, 7) systolic blood pressure, 8) diastolic blood pressure, 9) left ventricular voltage on a electrocardiogram at rest and 10) hematocrit. The plasma carnitine levels in these patients were markedly reduced and inversely correlated with the cardiothoracic ratio (CTR) on the chest X-ray films (r = 0.38, p less than 0.05). In principal component analysis, the CTR was closely related to hematocrit and plasma carnitine levels. By multiregression analysis, both hypo-carnitinemia and anemia were independently shown to be important causes of cardiomegaly. Thus, it is suggested that the cardiomegaly in patients with chronic hemodialysis may be improved by supplemental therapy with l-carnitine, even in cases with severe anemia.

A recently developed highly sensitive radioimmunoassay method for detecting plasma kinin was used to re-evaluate the results of previous studies, in which plasma kinin had been measured with a bioassay method. To clarify the mechanism of plasma kinin release in global myocardial ischaemia the left main coronary artery was cannulated using a Griggs type autoperfusing cannula after pentobarbital anaesthesia in open chest dogs. The animals were divided into a non-coronary constricted group (n = 4) and a moderately coronary constricted group (n = 7). Cardiac sympathetic nerve stimulation (10 V, 4 Hz, 2 ms duration) was given to both groups. Haemodynamic recordings and blood samples were taken before and after coronary constriction as well as after sympathetic nerve stimulation. The arterial and coronary sinus plasma kinin concentrations were determined with the new radioimmunoassay method. After sympathetic nerve stimulation apparent myocardial ischaemia occurred and the plasma kinin concentration in coronary sinus blood increased significantly in the constricted group. In the non-constricted group, however, myocardial ischaemia did not appear and no significant change in coronary sinus plasma kinin concentrations was seen. These findings show that there was a pronounced release of plasma kinin from the heart when apparent myocardial ischaemia occurred.

In order to compare sympathetic nerve activity among subgroups in essential hypertensives, with reference to labile or stable hypertension and to level of plasma renin activity (PRA), the urinary excretion of catecholamines, serum dopamin-beta-hydroxylase (DBH) activity and pressor response to infused noradrenaline (NA-response) were estimated in the patients with essential hypertension. The measurements were performed during the first and the last four days of two weeks of rest after admission to the hospital, during which the patients were kept at rest with neither medication nor salt-restriction. Patients were divided into two groups with a reduction of mean arterial pressure (MAP) by more than 10 mmHg (Responder) and less then 9 mmHg (Non-Responder) following two weeks of rest, or into three renin subgroups, i.e., low, normal and high PRA. From the measurements during the first four days of two weeks, the following results were obtained. In the Responder, a 24 hour urinary excretion of noradrenaline (NA) and the increase of urinary NA during two hours of 60° head-up tilt were significantly augmented (p < 0.01 and p < 0.05, respectively) and NA-response was suppressed (p < 0.05) as compared with the Non-Responder. In addition, a significantly negative correlation was found between the increase of urinary NA by the tilt during this period and the changes in MAP following two weeks of rest. However, a significant difference between the Responder and the Non-Responder did not exist in age, values of heart rate (HR), MAP, cardiac index (CI), total peripheral resistance index (TPRI), plasma volume (PV), extracellular fluid volume (ECFV), total exchangeable sodium (Nae) and serum DBH. Comparison among low, normal and high PRA patients revealed significantly lower urinary NA excretion (p < 0.001) and serum DBH activity (p < 0.05) in the low PRA patients. NA-response was significantly higher (p < 0.001) in the low PRA patients than in the normal PRA patients, both of which were significantly higher than in the high PRA patients or the normotensive subjects. PV, ECFV and Nae of the low PRA patients were significantly more elevated than those of both the normal and high PRA patients, whereas no significant difference was found in HR, MAP, CI and TPRI among these three patient groups. These findings suggest that an augmentation of sympathetic nerve activity exists, and it possibly plays a role in blood pressure rise in the patients with labile type of essential hypertension. The patients with low renin essential hypertension exhibited a suppressed sympathetic nerve activity, which might be not primary but rather secondary as the results of changes in water-sodium balance.

In order to clarify the properties of sympathetic nerve activity in low renin essential hypertension, plasma catecholamines (CA), dopamine-β-hydroxylase (DBH) activity and urinary CA were measured and the changes of these variables induced by 60° head-up tilt or i.v. injection of tyramine (0.1 mg/kg) were also measured in in-patients with low renin (LRH) and normal renin essential hypertension (NRH). IN addition, blood pressor response to tyramine, i.v. infusion of 0.3 μg/kg/min. of noradrenaline (NA Response) and 0.015 μg/kg/min. of angiotensin-II (ANG-II Response) were determined before and after salt restriction (Na 35, K 75 mEq) for 7 days or salt loading (Na 390, K 75 mEq) for 14 days. The basal values of plasma noradrenaline (NA), plasma DBH, and 24 hour urinary excretion of NA in LRH were significantly lower than in either NRH (p < 0.01, 0.05 and 0.01, respectively) or normotensive subjects (p < 0.05, 0.05 and 0.001, respectively). Plasma NA, plasma DBH and urinary output of NA clearly rose after 30 min. to two hours of the tilt in both LRH and NRH, and the maximal values of plasma NA (p 0.05) during tilting was significantly lower in LRH compared with those in NRH, while no significant difference was observed in the changes of plasma DBH and urinary NA between LRH and NRH. Following i.v. injection of tyramine, the maximal value of plasma NA and blood pressure rise was significantly lower (p 0.05) and significantly higher (p 0.05) than those in NRH, respectively. Following salt restriction, significant reduction of mean arterial pressure (MAP), pressor response to NA and ANG-II and a marked augmentation of PRA and urinary NA were observed. LRH showed a more marked reduction of MAP (p 0.01) and of NA Response (p 0.05) and a significantly higher augmentation of urinary NA excretion (p 0.05) than those in NRH. The increase of PRA (p 0.02) and the decrease of ANG-II Response (0.05 p 0.1) were less in LRH than in NRH. On the other hand, following salt loading, LRH exhibited a significant elevation of MAP and diminution of urinary NA, which differed markedly (p 0.01 and p 0.001) from those in NRH, in whom no significant changes were observed. No significant difference was observed between LRH and NRH in the other variables. These findings suggest that, in LRH, there exists a reduced sympathetic nerve activity at rest and a suppressed sympathetic responsiveness to the postual and tyramine stimulation, and these reduced sympathetic activity might be not primary but rather secondary to the changes in water-sodium balance.

In order to quantify the size of the infarcted myocardium, two kinds of data processing techniques were applied to single photon emission computed tomography (SPECT) with thallium-201 and its clinical reliability was evaluated by comparing it with the infarct sizing procedure with the serial serum creatine kinase-MB measurements in 14 patients with acute myocardial infarction. After maximum-count circumferential profile analysis, short axis images were reformatted into an unfolded surface map and a bull's eye view map. The SPECT-determined infarct size was defined as the area or the percentage of hypoperfused myocardium of which the profile count was less than the mean minus 2SD derived from 8 normal subjects. The infarct area was calculated from the number of pixels with an abnormal count and expressed in an unfolded surface map. The percentage was calculated from the number of abnormal profile points and displayed in a bull's eye view map. A high linear correlation was observed between the enzymatically determined infarct size and the infarct area or the percentage (r = .947, r = .872, respectively), despite underestimations in 2 patients with accompanying right ventricular infarction and overestimations in 2 patients with prior anterior infarction. Moreover, a close negative correlation was found between the left ventricular ejection fraction and the infarct area or the percentage (r = .836, r = .821, respectively). Thus, the semiautomatic techniques for processing thallium-201 SPECT images might contribute to the quantitative estimation and display of infarcted myocardium and have high clinical reliability.