Search PubMed⌕ Search

Biomedical subjects

K Machii

Publications and source records attributed to K Machii.

At least 73 records · Page 4Linked to original sources

[Out-of-hospital sudden cardiac death: a comparative study spanning 10 years].

Incidence, etiology and time zones of sudden cardiac deaths were compared for 1986 and 1976. Totals of 1,140 cases of acute endogeneous deaths, 590 in 1986 and 550 in 1976, were sent for coroner's inquest in Kanagawa Prefecture. These were the materials for the present study. Sudden cardiac deaths included 239 (46.1%) in 1986 and 137 (37.4%) cases in 1976 in males, and 81 (47.1%) in 1986 and 74 (40.0%) cases in 1976 in females. There were 129 (21.9%) and 163 (29.6%) cases with cerebral hemorrhages in 1986 and 1976, respectively. The acute cardiac death was the most frequent cause among acute endogenous deaths, and it approximately doubled among males during an interval of 10 years. It was related to a marked increase in ischemic heart disease (from 89 to 170 cases) in males compared to a slight increase among females (from 58 to 76 cases). Non-ischemic acute cardiac deaths were frequently noted in males; 38 (27.7%) and 27 (11.4%) cases in 1976 and 1986, respectively. In ischemic heart disease, deaths most frequently occurred about midnight (from 12 a.m. to 1 a.m.) or in the evening (from 5 p.m. to 6 p.m.), and deaths due to acute cardiac failure occurred during sleep. Time zones of evening deaths in ischemic heart disease corresponded to the report of Muller et al., but, the peak about midnight was not reported. This difference may be explained by the circadian rhythm theory, however, heavy alcohol intake and spasmogenicity in the Japanese people may also play roles in midnight deaths.

Adolescent↗

T cells subsets responsible for clearance of Sendai virus from infected mouse lungs.

T cell subsets responsible for clearance of Sendai virus from mouse lungs determined by adoptive transfer of immune spleen cell fractions to infected nude mice. T cells with antiviral activity developed in spleens by 7 days after intranasal infection. Spleen cell fractions depleted of Lyt-2+, Lyt-1+, or L3T4+ cells showed antiviral activity in vivo, although the degree of the activity was lower than that of control whole spleen cells. The antiviral activity of the Lyt-2+ cell-depleted fraction was consistently higher than that of L3T4+ (Lyt-1+)-depleted cells. In vitro cytotoxic activity against Sendai virus-associated, syngeneic lipopolysaccharide-blast cells was detected in stimulated cells from intraperitoneally immunized mice but was lost after depletion of Lyt-2+ cells. Multiple injection of anti-Sendai virus antibody into infected nude mice had no effect on lung virus titer. These results indicate that L3T4+ (Lyt-1+) and Lyt-2+ subsets are cooperatively responsible for efficient clearance of Sendai virus from the mouse lung.

Animals↗

Differences in response of myosin isozyme transition of ordinary and specialized myocardium to overload.

To investigate the response of myosin isozyme transition in specialized myocardium to cardiac overload, we examined immunohistochemically the distribution of myosin isozymes in sinus node cells of overloaded canine atria, using the monoclonal antibodies CMA19 and HMC14, which are specific for atrial myosin heavy chain (alpha-HC) and ventricular myosin heavy chain (beta-HC), respectively. Overloading in canine right atria was induced by artificial tricuspid valve regurgitation and pulmonary stenosis. Right atrial mean pressure rose to 15-20 mm Hg (n = 4) 2 months after surgery. In the working myocardium, cardiac overload caused redistribution of myosin isozymes, alpha-HC to beta-HC. Compared with the normal right atria, fewer myocytes were labeled with CMA19, but more were labeled with HMC14. However, the reactivity of sinus node cells with CMA19 and HMC14 was not changed between normal and overloaded right atria, indicating no redistribution of myosin heavy chain isozymes, alpha-HC to beta-HC. These results suggest that isozymes in myosin heavy chains in the specialized myocardium are protected from overload effects by their firm cytoskeletal framework or other mechanisms.

Animals↗

Reactivities of 4 murine coronavirus antigens with immunized or naturally infected rat sera by enzyme linked immunosorbent assay.

Four murine coronavirus antigens, sialodacryoadenitis virus (SDAV) strain TG, Parker's rat coronavirus (PCV) strain 8190, mouse hepatitis virus (MHV) strains S and NuU, were examined for their reactivities to hyperimmunized and naturally infected rat sera by ELISA. With the immunized sera, SDAV and PCV antigens reacted best with respective homologous sera. MHV antigens reacted with all antisera, anti-SDAV, anti-PCV, and anti-MHV-S at approximately the same level, and MHV-S showed a slightly higher reactivity than MHV-NuU. The reactivities of the sera from various colonies to these antigens were in the order--from high to low--of SDAV, MHV-S, MHV-NuU, and PCV. None of sera negative for SDAV antigen reacted positively to the other antigens. Within the sera positive for SDAV, the positivities were in the order of MHV-S, MHV-NuU, and PCV. These results suggested that, although homologous antigens are best to detect SDAV or PCV infection by ELISA, MHV antigen can be used if highly cross-reactive viral strain is selected.

Animals↗

[Continuity of normal and prolapsed mitral valves: two-dimensional and color Doppler echocardiographic investigations].

To certify the continuity between the normal and prolapsed mitral valves (MVP), two-dimensional and color Doppler echocardiography (2-DE and CDE) were performed for healthy 250 male subjects of 13 years old. The distance from the plane of the mitral annulus to the coaptation (c) and the grade of systolic ballooning of the anterior mitral leaflet as expressed by the maximum distance between the leaflet and the straight line connecting the anterior mitral ring with the point of coaptation (d) were measured in the long-axis 2-DE. Mitral regurgitation (MR) was evaluated by CDE. Distribution of c was between +10 and -3 mm, and d was between +5 and -3 mm (minus denotes prolapse toward the left atrium). An approximately normal distribution was found in both parameters c and d. The incidence of MVP varied from 3 to 13% according to the strictness of the criteria for MVP. Subjects with MR from the posterior commissure showed the coaptation significantly displaced toward the atrium compared with the rest of subjects (p less than 0.01). Our data suggest that MVP is a multifactorial disorder of the valve and the development of MR has some relation to the severity of MVP.

Adolescent↗

[Tricuspid regurgitation in mitral valve prolapse studied by two-dimensional color flow mapping].

To assess the incidence of tricuspid regurgitation (TR) in mitral valve prolapse (MVP), 96 patients with MVP and 23 normal control subjects were studied. Subjects in the MVP group were further classified as a group with mitral regurgitation (MR(+) group: 61 cases), and MR(-) group (35 cases). The presence of TR in each group was studied by two-dimensional color flow mapping using a Toshiba SSH-65A apparatus. The incidence of TR was 49% in the MR(+) group and 34% in the MR(-) group, and both (35 cases). The presence of TR in each group was studied by two-dimensional color flow mapping using a Toshiba SSH-65A apparatus. The incidence of TR was 49% in the MR(+) group and 34% in the MR(-) group, and both values were statistically greater than 9% in the control group (p less than 0.001 and p less than 0.05, respectively). A female preponderance was observed only in the MR(+) group. Tricuspid valve prolapse was observed in six cases (10%) in the MR(+) group, two cases (6%) in the MR(-) group, and none in the control group. The mean tricuspid ring dimension did not differ significantly among the three groups. The female patients in MR(+) group had statistically greater measurements than the normal female subjects (p less than 0.01). In conclusion, the incidence of TR was statistically greater in female patients in the MR(+) group than in females in the other groups. It is suspected that functional or pathological changes which induce MVP are likely to progress to the tricuspid ring in female patients.

Adolescent↗

[Dissecting aortic aneurysm of DeBakey type II diagnosed by color Doppler flow imaging and treated by a Bentall surgical procedure: a case report].

A 33-year-old man with known annuloaortic ectasia was admitted to the hospital because of chest pain. A dissecting aortic aneurysm was strongly suspected, but angiography was not performed because of his history of allergic reaction to iodine contrast material. Two-dimensional echocardiography demonstrated a markedly dilated basal aorta. The aortic wall immediately above the right sinus of Valsalva appeared to divide the aortic lumen into anterior and posterior channels. A defect in the intimal flap with a diameter of two cm was also detected six cm above the aortic ring. Color Doppler flow mapping showed blood flow passing through a probable entrance tear from the true lumen into the false lumen. Reentry could not be detected by Doppler imaging. All major aortic tributaries were presumed patent and supplied via the true lumen. The patient underwent successful emergency Bentall surgical procedure and recovered. It is emphasized that in some cases of DeBakey type I or II aortic dissection, color Doppler flow imaging is helpful for determining indications for emergency surgery.

Adult↗

Right ventricular filling detected by pulsed Doppler echocardiography during the convalescent stage of inferior wall acute myocardial infarction.

To evaluate right ventricular (RV) diastolic function in patients with inferior wall acute myocardial infarction (AMI), flow velocity patterns of the RV inflow tract were studied in patients with anterior AMI (n = 32), inferior AMI (n = 32) and angina pectoris without left ventricular asynergy (n = 10) using pulsed Doppler echocardiography. Doppler examinations were performed at least 4 weeks after the attack. Twenty-seven healthy persons served as control subjects. Three Doppler variables were measured at the RV inflow tract: the ratio of the late diastolic peak flow velocity due to atrial contraction to the rapid filling peak flow velocity in early diastole (A/E) and the acceleration time and deceleration time of the RV rapid filling wave. A/E in patients with inferior AMI (1.01 +/- 0.24, mean +/- standard deviation) was significantly greater than in those with anterior AMI (0.80 +/- 0.16, p less than 0.001) and angina pectoris (0.79 +/- 0.17, p less than 0.01) and in normal subjects (0.70 +/- 0.17, p less than 0.001). A/E in patients with inferior AMI correlated with the ratio of left ventricular to RV end-diastolic pressure (r = -0.60, p less than 0.05). A/E in inferior AMI with relatively high RV end-diastolic pressure (more than 8 mm Hg, n = 8) was significantly greater than that in those with normal pressure (8 mm Hg or less, n = 9). A/E in patients with proximal right coronary artery occlusion was significantly greater than that in those with distal occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Quantitative relationship between left ventricular function and serum cardiac myosin light chain I levels after coronary reperfusion in patients with acute myocardial infarction.

To estimate the extent of myocardial infarction after coronary artery reperfusion, serum levels of cardiac myosin light chain (LC) I and creatine kinase (CK) were determined serially in 49 patients with acute myocardial infarction. Intracoronary thrombolysis was successful in 25 patients (reperfusion group), and 24 patients were treated in a conventional manner (control group). The peak level of CK appeared significantly earlier in the reperfusion group (11.3 +/- 3.1 hr, mean +/- SD) than in the control group (21.6 +/- 7.2 hr). Cumulative release of CK was significantly related to angiographically determined left ventricular ejection fraction 1 month after the attack in both groups (r = -.50; -.45, respectively). However, the amount of cumulative release of CK in the reperfusion group was greater compared with that in those with the same left ventricular ejection fraction in the control group. Peak appearance time of LCI was almost equal in the two groups (3.8 +/- 1.4 vs 3.9 +/- 1.2 days). Peak levels of LCI were related to the left ventricular ejection fraction in the reperfusion group (r = -.63) and in the control group (r = -.74), and the slopes of their regression lines were similar. The cardiac index obtained on the day of onset in the two groups was related to peak levels of LCI but not to total release of CK. These results suggest that serum levels of LCI reflect the changes in left ventricular function after acute myocardial infarction, regardless of the presence of coronary reperfusion. Thus, serial determinations of LCI in serum facilitate noninvasive assessment of the effects of intracoronary thrombolysis on infarct size.

Adult↗

Prediction of pulmonary arterial pressure in adults by pulsed Doppler echocardiography.

Doppler echocardiography was used to estimate pulmonary artery (PA) pressure in 45 adult patients with various kinds of heart disease and the patterns were compared with those of 32 normal control subjects. Doppler signals obtained in the right ventricular (RV) outflow tract just proximal to the pulmonary valve and electrocardiogram were recorded simultaneously. Doppler velocity time intervals were measured as follows: RV preejection period, acceleration time from the onset of the RV ejection flow velocity to the peak, and RV ejection time. Thirty patients had PA hypertension and 16 patients had a low cardiac index. The best correlation with PA pressure was achieved by the RV preejection period/acceleration time index (r = 0.89 vs mean pressure). Sensitivity and specificity for predicting PA hypertension were 93% and 97%, respectively. Acceleration time correlated best with the logarithm of PA mean pressure (r = 0.88). Patients were separated into 2 groups according to cardiac index. In those patients with a cardiac index of less than 2.5 liters/min/m2, both RV preejection period/acceleration time and acceleration time were significantly correlated with PA mean pressure (r = 0.87) and log (PA mean pressure) (r = -0.87), respectively. However, the slope of the regression line for acceleration time and log (PA mean pressure) was significantly steeper than that for patients with a cardiac index of greater than or equal to 2.5 liters/min/m2 (p less than 0.05), whereas the relation between RV preejection period/acceleration time and PA mean pressure in the 2 groups could not be differentiated statistically from each other. Other intervals and ratios were less quantitative because of late systolic turbulent flow and individual variability.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Prevalence of antibodies to Sendai virus and rotavirus in laboratory rabbits.

One hundred and sixty rabbit sera from 10 breeding colonies and 13 laboratory colonies were tested for antibodies to Sendai virus and rotavirus by enzyme-linked immunosorbent assay (ELISA). Antibodies were detected to Sendai virus in 53% and to rotavirus in 81%, indicating the prevalence of these viral infections in laboratory rabbit colonies.

Animals↗

[PTCA in patients undergoing coronary bypass surgery and its potential availability: when can PTCA be an alternative to coronary artery bypass grafting?].

The potential availability of percutaneous transluminal coronary angioplasty (PTCA) was retrospectively evaluated for the responsible lesions among grafted vessels of 149 patients who underwent coronary artery bypass grafting (CABG). The lesions suitable for PTCA were defined as discrete, segmental, subtotal and noncalcific, in proximal or middle portions of the major coronary arteries. Patients with left main trunk lesions, those with obstruction of two major coronary arteries, and those with lesions in donor arteries of jeopardized collaterals were excluded. Ninety-seven (31%) of a total of 308 grafted lesions were appropriate for PTCA. These included 38% of left anterior descending artery (LAD) lesions, 39% of left circumflex artery (CX) lesions, and 14% of right coronary artery (RCA) lesions. At least one lesion of 77 (52%) of 149 patients was suitable for PTCA. These included 66% of single vessel graft candidates, 54% of double vessel graft candidates, and 38% of triple or more vessel graft candidates. Ideal candidates for PTCA were 34 patients (23%) in whom all lesions in the grafted vessels were thought to be appropriate for PTCA, and these included 25 (LAD: 23, CX: 1, RCA: 1) of 38 single vessel graft candidates and nine (LAD + RCA: 6, LAD + CX: 2, CX + RCA: 1) of 111 multivessel graft candidates. There was no significant difference between the clinical characteristics of the patients ideally suited for PTCA and the remaining patients. Additional 25 candidates for multivessel grafting, whose lesions were appropriate for PTCA except that of the LAD, were considered limited candidates for PTCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗

[Clinical problems in mitral valve prolapse: an echocardiographic review].

Several unsolved problems in the echocardiographic diagnosis of mitral valve prolapse were reviewed. At present, two-dimensional echocardiography is the most reliable method for assessing mitral valve prolapse. However, basic knowledge on the anatomical orientation of the mitral annulus, hitherto not sufficiently studied, is indispensable before making adequate echocardiographic diagnosis. The annulus is not like a geometrical plane and occupies certain millimeters' width between the left atrium and the ventricle. Therefore, assuming the left atrial margin of the annulus as the reference, many unmistakable prolapse with mitral regurgitation are overlooked, while assuming the left ventricular margins as the reference, some false positive diagnoses will be inevitable. Consulting several autopsy specimens, the author noticed that the central fibrous body, the site of the anterior mitral valve insertion to the interventricular septum, forms the most inferior part of the mitral annulus. This fact could explain a higher sensitivity of the apical four-chamber view for detecting anterior mitral valve prolapse reported by several investigators, and also more frequent over-diagnosis according to our experience. Although the author prefers the left ventricular margin of the mitral annulus defined by the long-axis view as the reference for echocardiographic diagnosis of mitral prolapse, further investigation should be made in relation to the clinical significance of this abnormality diagnosed by echocardiography.

Echocardiography↗

[Mitral regurgitation due to abnormal reinsertion of chordae tendineae (looping) of the posterior mitral leaflet: clinical and echocardiographic features].

Two-dimensional (2D) echocardiographic and clinical characteristics of patients with mitral regurgitation (MR) due to abnormal reinsertion of chordae tendineae (looping) in the middle scallop of the posterior leaflet were described and compared with those of patients with chordal rupture of the posterior leaflet. Twenty-five patients with posterior mitral valve prolapse who underwent mitral valve replacement were studied. They were categorized in three groups; 14 patients with MR due to ruptured chordae tendineae (RCT) of the posterior leaflet (RCT group); three patients with looping of the chordae tendineae in the middle scallop of the posterior leaflet (looping group); and eight patients with both RCT and looping (looping + RCT group). It was difficult to distinguish the looping group from the other two groups by their 2D echocardiographic findings, which were characteristic of those of RCT. However, the following findings were more frequently encountered in the patients with looping than in those without: 1) aberrant or absent systolic coaptation with salient arc of the posterior leaflet, observed in six of the RCT group (43%), two in the looping group (67%) and seven in the looping + RCT group (88%); 2) with thickened edges of the posterior leaflet, shown in three of the RCT group (21%), two of the looping group (67%) and five of the looping + RCT group (63%) in the long-axis view, and also noticed in four of the RCT group (29%), two of the looping group (67%) and six of the looping + RCT group (75%) in the short-axis view. In the clinical history, the onset of a heart murmur, congestive heart failure and surgical treatment occurred at significantly younger ages in the looping group than in the RCT group. As for hemodynamic parameters, pulmonary hypertension was significantly milder in the looping group than in the RCT group. In conclusion, although 2D echocardiographic findings of patients with looping were similar to those of patients with RCT, it seemed possible to differentiate the looping group from the RCT group by the 2D finding of a prolapsed posterior mitral valve with a salient arc and a thickened edge. It was also suggested that the looping of chordae tendineae in the middle scallop of the posterior leaflet was congenital in origin.

Adolescent↗

[Pseudoaneurysm of the left ventricle serially demonstrated from on-set using two-dimensional echocardiography: a case report].

A case of so-called pseudoaneurysm of the left ventricle without pericardial adhesion, serially demonstrated by two-dimensional echocardiography, was reported. A 76-year-old man developed congestive heart failure 10 hours after gastrectomy, and was diagnosed as having acute myocardial infarction. Two-dimensional echocardiography on the 21st day after onset revealed moderate pericardial effusion and an echo-free space in the posterolateral myocardium of the left ventricle. The echo-free space gradually expanded exteriorly and formed an aneurysm, which remained unchanged after the resolution of the pericardial effusion. Clinical diagnosis of pseudoaneurysm of the left ventricle was made by left ventriculography and coronary angiography. At autopsy, there was an aneurysm measuring 2.3 X 3.0 X 5.0 cm which communicated with the left ventricle via two small ostia, 5 mm each in diameter. There was a loose fibrous adhesion between the pericardium and the epicardium. The wall of the aneurysm consisted of organized fibrous tissue without any elements of the myocardium. Both myocardium and fibrous tissue were located at the junction of the left ventricular wall and the aneurysm. It is surmised that dissection of the infarcted myocardium expanded so greatly as to form an aneurysmal cavity, resulting in the formation of a so-called pseudoaneurysm of the left ventricle after fibrous changes of the outer wall in the infarcted myocardium. Therefore, this aneurysm might be termed a "dissecting" aneurysm of the left ventricle. The hypothesis that a pseudoaneurysm is derived from a localized hemopericardium should be reconsidered.

Aged↗

[Biochemical assessment of the effects of coronary thrombolysis by serum cardiac myosin light chain levels].

To establish the method of biochemical assessment of effects of intracoronary thrombolysis after acute myocardial infarction (MI), the relationships between plasma creatine kinase (CK) or serum cardiac myosin light chain (LC) I levels and changes in left ventricular (LV) wall motion were evaluated. Twenty-seven cases with acute MI without previous infarction were included in this study. Intracoronary thrombolysis was successful within seven hours after onset of MI in 13 patients (reperfusion group), and 14 patients were treated in a conventional manner (control group). Peak levels of CK reached earlier in the reperfusion group (11.3 +/- 2.9 hours) than in the control group (20.9 +/- 5.3 hours). The peak appearance time of CK in the reperfusion group was significantly related to the time between the onset of MI and achievement of coronary reperfusion (r = 0.76). The relationship between total CK release and LV ejection fraction determined by cineangiography one month after onset was not good (r = -0.42). Peak levels of CK were not related to LV ejection fraction. Peak levels of LC appeared about four days after onset in both groups. Peak levels of LC were closely related to LV ejection fraction (r = -0.72). Twenty-four-hour and four-day levels of LC were also related to LV ejection fraction (r = -0.62 and -0.73, respectively). Peak levels of LC were related to asynergic area determined by biplane cineangiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Metastatic thyroid cancer to the right ventricle causing obstruction of the right ventricular outflow tract and associated with disseminated intravascular coagulopathy: a case report].

A case of thyroid cancer causing right ventricular outflow tract obstruction is described. A 72-year-old woman was admitted because of shortness of breath, some ecchymoses, and marked anasarca. Her liver was palpable four fingerbreadths below her costal margin. Laboratory findings included leukocytosis, marked thrombocytopenia, and an increase in fibrinogen degradation products due to disseminated intravascular coagulopathy. Two-dimensional echocardiography demonstrated a solid mass in the right ventricle, which protruded into the right atrium and main pulmonary artery. Right ventricular outflow tract obstruction and tricuspid regurgitation were demonstrated by contrast echocardiography. These findings were confirmed by CT scans, RI angiography, and contrast angiography. The mass was partially resected from her right ventricle and her tricuspid valve was replaced successfully, but she died of sepsis three weeks after surgery. At autopsy, undifferentiated thyroid cancer and cardiac metastasis were verified. To date, only eight cases with initial symptoms of congestive heart failure due to right ventricular outflow tract obstruction caused by metastatic intracavitary tumors have been reported. Very rarely have cardiac tumors resulted in disseminated intravascular coagulopathy.

Aged↗