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Biomedical subjects

K Takayanagi

Publications and source records attributed to K Takayanagi.

At least 91 records · Page 5Linked to original sources
PubMed1994

Vasodilatory capacity of coronary resistance vessels in dilated cardiomyopathy.

Both the endothelium-dependent and endothelium-independent vasodilatory responses of coronary resistance vessels were studied in patients with dilated cardiomyopathy (DCM). A 3F coronary Doppler catheter was placed in the proximal left anterior descending artery in 14 patients with DCM and in 10 patients with chest pain syndrome and a normal heart (control subjects). The ratio of maximum mean coronary blood flow velocity after intracoronary administration of the endothelium-independent vasodilator papaverine (10 mg) to resting mean coronary blood flow velocity (Vp/Vo) in patients with DCM was diminished compared with that in control subjects (2.2 +/- 0.6 vs 4.1 +/- 0.9, p < 0.001). The ratio after administration of the endothelium-dependent vasodilator acetylcholine (40 micrograms) (Va/Vo) in 10 DCM patients was also diminished compared with that in seven control subjects (1.3 +/- 0.5 vs 2.4 +/- 0.8, p < 0.01). In DCM patients, Vp/Vo was correlated with left ventricular end-diastolic pressure (r = -0.48, p < 0.05), left ventricular end-diastolic volume index (r = -0.68, p < 0.01), ejection fraction (r = 0.75, p < 0.01), and left ventricular end-diastolic wall stress (r = -0.73, p < 0.01). However, Va/Vo was not correlated with any of these parameters. These results indicate that impairment of the vasodilatory capacity of coronary resistance vessels in DCM may be related to endothelial dysfunction and to an extravascular factor resulting from left ventricular dysfunction.

Acetylcholine↗
PubMed1994

New approach to assess quality of life in neonatal surgical cases: medical providers' subjective assessment of disease- and condition-related factors, using the linear analogue scale.

A new questionnaire survey of pediatric surgeons and nurses, using the linear analogue scale, was used to determine subjective assessments of patients' quality of life (QOL) with regard to neonatal surgical diseases and conditions, including those involving anal and urinary functions. The results were analyzed according to the medical providers' years of professional experience. For six neonatal surgical diseases, QOL was assessed more favorably by less experienced surgeons and nurses. The result was similar for adulthood diseases. The development of medical technology can be attributed to this trend; however, QOL for patients with diaphragmatic hernia was assessed less favorably by less experienced surgeons (as 66.1%) than by more experienced surgeons (as 81.6%). Current technology has enabled the survival of neonatal surgical patients who are born prematurely and/or who have serious diseases or anomalies. Consequently this leads to poorer assessment of the surviving patients' QOL. QOL for patients with imperforate anus and spina bifida remained less favorably assessed. That of patients with conditions related to anal and urinary dysfunctions also scaled in the same manner. Anal dysfunction was less favorably assessed by less experienced surgeons (as 40.0%) than by more experienced surgeons (as 49.4%). In part, this discrepancy could be attributed to (1) better adjustment by the patients to their condition over time, and (2) greater focus on QOL issues in recent years. With regard to anal function, low QOL assessment correlated strongly with imperforate anus, Hirshsprung's disease, and spina bifida (P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

QT prolongation and possibility of ventricular arrhythmias after intracoronary papaverine.

The incidence of ventricular arrhythmias following the intracoronary injection of papaverine was assessed. A 3F coronary Doppler catheter was placed in the proximal left anterior descending artery and 6-12 mg of papaverine was injected into the left coronary artery in 42 patients. After intracoronary papaverine, the corrected QT interval on the electrocardiogram was prolonged from 0.43 +/- 0.03 to 0.49 +/- 0.07 s (p < 0.001). Occasional premature beats were observed in 2 patients (4.5%) with dilated cardiomyopathy. In 1 patient (2.3%) with 99% stenosis of the left anterior descending artery, polymorphous ventricular tachycardia with marked QT prolongation occurred. This patient also had hypokalemia (2.5 mEq/l) due to primary aldosteronism. In conclusion, careful use of intracoronary papaverine is necessary because of the risk of occasional serious ventricular arrhythmias.

Adult↗
PubMed1994

Days required for 75% suppression of ventricular premature contractions by antiarrhythmic agents obtained from continuous in-hospital ECG monitoring.

To determine the number of days required to obtain 75% suppression of ventricular premature contractions (VPCs) by antiarrhythmic agents, which was expressed as t1/4, we performed 32 in-hospital continuous all day ECG monitoring trials in four groups of 28 symptomatic patients (ages; 54 +/- 20 years-old) with frequent VPCs. Nine patients had no organic heart disease (group 1, 11 trials), nine had valvular heart disease (group 2, 10 trials), three had dilated cardiomyopathy (group 3, 3 trials) and seven had myocardial infarction within two to four weeks onset (group 4, 8 trials). All patients were monitored by ECG telemetry with an arrhythmia analyzer, which could count hourly and daily VPCs. Class I antiarrhythmic agents were given in 18 trials, class II in two trials and class I+ class II in 12 trials. Plasma concentrations of the antiarrhythmic agents were monitored in 11 trials. In 21 trials, t1/4 could be obtained; ten (91%), six (60%), three (100%) and two trials (25%) in the four groups, respectively (p < 0.05). The value of t1/4 in the four groups was 6 +/- 6, 7 +/- 6, 14 +/- 11 and 13 +/- 2 days, respectively (mean 8 +/- 7 days; N.S.). Immediate response to the initial antiarrhythmic agent administration, expressed as percent VPC count after three hours, correlated significantly with t1/4 (r = 0.696, p = 0.0006), but ejection fraction, patient's age, control VPC counts or plasma antiarrhythmic agent level did not correlate with t1/4. In conclusion, t1/4 is a useful index for the evaluation of VPC suppression, revealing wide inter-individual variations and can be roughly estimated from the immediate response to the initial antiarrhythmic agent administration.

Adolescent↗
PubMed1994

Torsades de pointes in paced patients with sick sinus syndrome after disopyramide administration.

Three ventricular inhibited mode (VVI) pacemaker implanted patients, all above 65 years, female and having sick sinus syndrome suffered from torsades de pointes; one patient after 2.5 years and the other two patients within a day of disopyramide therapy. All had hypopotassemia and plasma disopyramide was below the therapeutic range in two patients. Torsades de pointes was induced following ventricular paced beats and suppressed by cessation of disopyramide in all or by setting a higher pacing rate in one. In our department, permanent VVI pacemakers were implanted in 43 patients with sick sinus syndrome including 26 with bradycardia-tachycardia syndrome, nine of whom were treated by disopyramide. Torsades de pointes was observed only in those disopyramide treated bradycardia-tachycardia patients. Our report stresses the proarrhythmic nature of combined VVI pacing and antiarrhythmic agents in the presence of hypopotassemia.

Aged↗
PubMed1994

Acute torn meniscus combined with acute cruciate ligament injury. Second look arthroscopy after 3-month conservative treatment.

The purpose of this study was to evaluate arthroscopically the natural healing of an acute torn meniscus combined with an acute cruciate ligament injury treated nonoperatively. There were 30 lateral and 10 medial meniscus tears associated with 25 acute anterior cruciate ligament and 7 posterior cruciate ligament injuries in 32 patients. There was more than 1 tear on some menisci for a total of 51 tear sites. Injuries to the menisci and ligaments were allowed to heal without surgery, but were given protective mobilization immediately in order to stimulate stress oriented healing of injured collagen fibers and promote circulation of synovial fluid to the meniscus and ligament. A Kyuro knee brace with a coil spring traction system was used to add adequate but not excessive stress to the associated injured cruciate ligament. All knees were examined and arthroscoped before and after a 3-month treatment period. Results indicated that 69% of the lateral menisci healed completely and 18% healed partially, whereas 58% of the medial menisci healed completely and none healed partially. Twenty of 25 anterior cruciate ligaments and 3 of 7 posterior cruciate ligaments healed satisfactorily. This study indicated that acute tears of the meniscus, even when they occur in association with a cruciate ligament injury, can heal morphologically with nonsurgical treatment.

Adolescent↗
PubMed1993

Coronary flow reserve in patients with dilated cardiomyopathy.

Coronary flow reserve was studied in patients with dilated cardiomyopathy. A 3F coronary Doppler catheter was placed in the proximal left anterior descending artery in each of 10 patients with dilated cardiomyopathy (CDM group), seven patients with coronary artery disease that involved only the left anterior descending artery (CAD group), and seven patients with chest pain syndrome and normal hearts (control group). Coronary flow reserve was calculated as the ratio of the maximum mean coronary blood flow velocity after intracoronary administration of papaverine (10 mg) to resting flow velocity (M/R). The time until maximum flow velocity was reached after papaverine administration (Tmax) was also measured. M/R was lower in the DCM (p < 0.001) and CAD (p < 0.001) groups when compared with the control group. Tmax was not abnormal in the DCM group but was prolonged in the CAD group (p < 0.05). In the DCM group, the M/R ratio correlated with the left ventricular end-diastolic pressure (r = -0.69; p < 0.05), the left ventricular end-diastolic volume index (r = -0.7; p < 0.05), the ejection fraction (r = 0.82; p < 0.01), the left ventricular mass (r = -0.7; p < 0.05), and the left ventricular end-diastolic wall stress (r = -0.84; p < 0.001). These results indicate that coronary flow reserve was decreased in patients with dilated cardiomyopathy and that the mechanism of its reduction may differ from that in patients with coronary artery disease.

Adult↗
PubMed1993

Venoarterial carbon dioxide tension gradient in acute heart failure.

The venoarterial carbon dioxide tension gradient (P[v-a]CO2) was studied in patients with acute myocardial infarction. Seven patients with congestive heart failure (CHF group) and 10 patients without heart failure (control) were enrolled in this study. In all patients, hemodynamics were continuously monitored. Simultaneously, arterial and mixed venous blood were sampled, and blood gases and lactate concentration were analyzed. At the initial measurement before therapy, arterial and mixed venous pH and bicarbonate values were within the normal range, and there was no significant difference between the CHF group and controls. There was also no difference in arterial oxygen tension under the differential conditions of oxygen inhalation. However, cardiac index and mixed venous oxygen saturation (SvO2) were significantly lower, while the oxygen extraction ratio (OER) and arterial lactate were significantly higher in the CHF group than in the controls. On the other hand, P[v-a]CO2 was significantly higher in the CHF group (7.8 +/- 2.6 vs. 3.5 +/- 2.2 mm Hg, p < 0.01). This finding was due to the elevated mixed venous carbon dioxide tension in the CHF group, since arterial carbon dioxide tension was the same in both groups. Analysis of a total of 42 measurements obtained during the therapeutic course in the CHF group revealed a correlation of P[v-a]CO2 with cardiac index (r = -0.3, p < 0.05), OER (r = 0.57, p < 0.001), SvO2 (r = -0.56, p < 0.001) and lactate (r = 0.62, p < 0.001). The increase in P[v-a]CO2 observed in acute heart failure suggests the evidence of intracellular acidosis despite the absence of acidemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Acid-Base Equilibrium↗
PubMed1993

Features of coronary artery lesions related to left ventricular aneurysm formation in anterior myocardial infarction.

To determine the factors of left ventricular aneurysm formation in acute myocardial infarction, the authors studied the distribution of coronary artery lesions and the left ventricular wall motion of 43 patients with anterior myocardial infarction. Of 15 patients with aneurysm, 9 (60%) showed a single-vessel disease with severe stenosis of the proximal left anterior descending artery. Of 9 patients with triple-vessel disease, 8 (89%) had no aneurysm. In patients with the aneurysm, the Gensini score of the culprit lesion was significantly higher (p < 0.05) and the score except for the culprit lesion was less (chi 2 = 5.7, p < 0.05). In 23 patients with single-vessel disease, the collateral score was significantly less (p < 0.05) in patients with the aneurysm. The systolic wall motion on the ventriculogram appeared more impaired in the anterior infarct area but well maintained in the posterior noninfarct area in patients with the aneurysm. In conclusion, the important factors of left ventricular aneurysm formation were as follows: (1) A culprit lesion of the myocardial infarction was severe, but other coronary artery lesions were mild. (2) Collateral vessels were poor. (3) The left ventricular wall motion of the infarct area was impaired, but that of the noninfarct area was relatively good.

Cardiac Catheterization↗
PubMed1993

Swine interleukin 2 activity produced by mesenteric lymph node cells.

Swine interleukin 2 (IL-2) activity was assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay using murine IL-2 dependent cell line (CTLL-2). The culture supernatant of mesenteric lymph node (MLN) cells stimulated with phytohemagglutinin-P (PHA) induced a generation of MTT formazan in a dose-dependent manner, suggesting dose-dependent proliferation of CTLL-2. The maximal swine IL-2 activity was observed in the culture of MLN cells at 1 to 2 x 10(7) cells/ml when stimulated with 20 to 40 micrograms/ml PHA for 48 hr. Based on these findings, a large culture of MLN cells to prepare swine IL-2 were performed under the following condition; cell concentration of 1 x 10(7) cells/ml, PHA concentration of 20 micrograms/ml, a culture scale of 200 to 400 ml, and a stirring speed of 30 rpm. Swine IL-2 activity was detected from 4 hr after PHA stimulation, and rapidly increased until 16 hr. Almost maximal IL-2 activity in stirring culture was observed at the incubation of 20 hr. Swine IL-2 was partially purified by Sephacryl S-200 gel filtration and the estimated molecular weight was about 32 kD based on the peak of IL-2 activity. The pI value of swine IL-2 was estimated to be approximately pH 5.3. Swine IL-2 was sensitive to acid (pH 3.2) or alkaline (pH 10.5), 4 or 8 M urea, trypsin, and the heating at 70 degrees C. These physico-chemical properties of swine IL-2 was similar to those of human, murine or feline IL-2.

Animals↗
PubMed1993

Pronounced ST-segment depression during paroxysmal supraventricular tachycardia.

To determine the clinical significance of ST-segment depression observed in paroxysmal supraventricular tachycardia (PSVT), we evaluated the 12-lead electrocardiogram (ECG) during spontaneous PSVT in 54 patients (27 men and 27 women: mean age +/- SD; 47 +/- 18 years), who came to our clinic for the treatment of PSVT. Coronary angiography was performed in 16 patients (16 to 74 years; mean = 50 +/- 18) and treadmill exercise testing was performed in 21 patients. A cardiac electrophysiological study was carried out in 24 patients. During PSVT, ST-segment score was calculated as the sum of the ST-segment depression in 12 leads. The correlations between the ST-segment score, PSVT rate and age of the patient were analyzed as follows: The most significant positive correlation was observed between the ST-segment score and the PSVT rate (r = 0.615, p < 0.000001). The next most significant correlation was found between the PSVT rate and the age of the patient (r = -0.500, p = 0.00011). A negative correlation was also observed between the ST-segment score and the age of the patient (r = -0.429, p = 0.0012). In 13 of 16 patients, coronary angiography did not reveal any significant (> or = 75% in area) stenosis. Exercise testing induced significant ST-segment depression in 3 patients, of whom two had significant coronary artery lesions. PSVT was due to atrioventricular reentry via an overt (n = 3) or concealed accessory pathway (n = 15), atrioventricular nodal reentry (n = 5) and sinus node reentry (n = 1). In conclusion, patients with a faster PSVT rate revealed more pronounced ST-segment depression than did those with a slower PSVT rate, possibly reflecting the modified repolarization process instead of coronary artery involvement.

Adult↗
PubMed1993

[A case of coronary artery embolism associated with combined valvular heart disease].

A 53-year-old-man afflicted with combined valvular heart disease and atrial fibrillation was admitted to our department complaining of chest pain. ST elevation on ECG (II, III, aVF) and elevated CPK value were recognized. He was diagnosed as having acute myocardial infarction, and percutaneous transluminal coronary recanalization was performed immediately. The coronary angiogram showed occlusions at the proximal left branch (#12). But these lesions could not be recanalized by 960000 IU urokinase administration. The cineangiogram after one month revealed perfect recanalization of these occlusions. Mitral stenosis with neovascularity to the left atrium and aortic regurgitation were recognized. We supposed this infarction caused by coronary embolism originated from left atrial thrombi. Acute myocardial infarction associated with mitral stenosis has been reported in fifteen cases previously in Japan, but only three cases revealed coronary occlusion in the acute phase with normal coronary artery in the chronic stage. However, there has been no report, except for this case, demonstrating occlusion in two coronary arteries at the same time. So, our case is the first report of the involvement of two coronary artery occlusions.

Aortic Valve Insufficiency↗
PubMed1992

Human fibroblast cells synthesize and secrete nerve growth factor in culture.

Using our enzyme immunoassay system developed for recombinant hNGF, we examined the synthesis and secretion of human NGF (hNGF) by human fibroblast (WS-1) cells. The amount of the factor secreted by WS-1 cells increased linearly and a significant amount of NGF was detected in the conditioned medium of WS-1 cultures. WS-1 NGF showed properties identical to those of recombinant human NGF in immunoreactivity and molecular weight. An increase in cell density or the withdrawal of serum from the culture medium caused a drastic decrease in the rate of NGF secretion. These results suggest that WS-1 cells are able to synthesize and secrete hNGF in culture and that the synthesis/secretion is regulated in a growth phase-dependent manner.

Cell Division↗
PubMed1992

Hemofiltration as treatment for patients with refractory heart failure.

Hemofiltration was performed in 15 patients with refractory congestive heart failure. All of these patients had oliguria, although intensive treatment with diuretics, digitalis, vasodilators, and catecholamines was prescribed. Hemofiltration was performed under hemodynamic monitoring in 14 patients. The water removal by hemofiltration decreased pulmonary arterial pressure, pulmonary capillary wedge pressure and right atrial pressure. Despite these hemodynamic improvements, nine patients (60%) died within one month after the start of hemofiltration; the causes were fatal arrhythmia in three, renal failure in two, sepsis in one and irreversible cardiogenic shock in three. Oliguria for over 15 h or a serum creatinine concentration of more than 4.0 mg/dl at the start of hemofiltration related to poor prognosis. In view of these results, hemofiltration for refractory heart failure should be started earlier and performed carefully in order to avoid arrhythmia, cardiogenic shock, and other complications.

Adult↗
PubMed1992

Left ventricular diastolic dysfunction in coronary artery disease: effects of coronary revascularization.

Left ventricular diastolic dysfunction was studied globally and regionally in patients with coronary artery disease, and the effects of coronary revascularization were evaluated. A total of 25 patients with angina pectoris who had a stenotic lesion (greater than or equal to 90%) in only left anterior descending branch underwent coronary revascularization [percutaneous transluminal coronary angioplasty (PTCA) in 13 patients and coronary artery bypass graft (CABG) in 12]. Nine patients with normal coronary artery were studied as controls. Left ventricular volume and radial axes were measured on serial frames of one cardiac cycle by cine left ventriculography. The radial axes were drawn from the left ventricular gravity to left ventricular wall at every 20 degrees. Left ventricular filling fraction and distension rate of radial axes were calculated at the times of 25%, 50%, 75%, and 100% of diastolic period, 100% being end-diastole. Although there were no significant changes of the systolic function by revascularization, the filling fraction increased from 11.2 +/- 2.6 to 14.5 +/- 3.5% (p less than 0.001) at 25% time of diastole, from 29.9 +/- 4.9 to 32.5 +/- 5.0% (p less than 0.05) at 50% time in the PTCA group, and from 11.8 +/- 3.7 to 13.4 +/- 3.8% (p less than 0.01) at 25% time in the CABG group. The distension rate of radial axis to the anterior wall also increased significantly at 25% and 50% time of diastole after revascularization, and the change was marked in the PTCA group. However, these increases did not apply to the control patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1992

Activation of the osmoregulated ompF and ompC genes by the OmpR protein in Escherichia coli: a study involving chimeric promoters.

The expression of each of the Escherichia coli ompF and ompC genes is activated by the common positive regulator, OmpR, in response to the medium osmolarity. The promoters for these genes consist of canonical -35 and -10 regions, and upstream OmpR-binding sites. In this study, we constructed a functional ompF-ompC chimeric promoter consisting of the OmpR-binding site of ompF, and the -35 and -10 regions of ompC, which was fused to the lacZ gene on a low-copy-number plasmid. It is known that the ompF and ompC genes are expressed in a different manner in cells with mutations in the ompR gene. In this respect, it was found that the ompF-ompC chimeric promoter behaves just like ompF promoter with respect to an ompR mutation (ompR472). It was revealed that, in this chimeric promoter, the OmpR-binding site must be located stereospecifically with respect to the -35 and -10 regions for OmpR-dependent transcription of the ompF-ompC chimeric promoter to occur. These results are discussed in relation to the structures and functions of the ompF and ompC promoters, the occurrence of a DNA curvature in the promoter regions being implied, which may be an important parameter for the transcription activation by the OmpR protein.

Bacterial Outer Membrane Proteins↗
PubMed1992

Effects of secondary organ failure on compensation of acute heart failure in patients with myocardial infarct and dilated cardiomyopathy.

Compensation for heart failure can be influenced by cardiac loads due to organ failure. This investigation studied the effect of secondary organ failure on the hemodynamics of acute heart failure. Of 106 patients with acute heart failure due to myocardial infarction or dilated cardiomyopathy, 49 (46%) patients had secondary organ failure, either kidney, liver, brain or blood. Their acute heart failure was sustained for significantly longer than that of 57 patients without organ failure. A transient but severe decompensation induced secondary organ failure, although the left ventricular ejection fraction was not different from that of the control without heart failure. Hypervolemia in cases of renal failure, bradycardia in loss of consciousness, hyperdynamic state in anemia and low blood pressure in liver dysfunction caused the sustained acute heart failure. These results suggested that secondary organ failure might occur in 46% of patients with acute heart failure, and might disrupt compensation by different kinds of hemodynamic loads in low cardiac function.

Acute Disease↗