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Biomedical subjects

K Tsuchihashi

Publications and source records attributed to K Tsuchihashi.

At least 73 records · Page 4Linked to original sources
PubMed1996

Serial changes of left atrial thrombus in mitral stenosis: transesophageal echocardiographic studies in candidates for balloon mitral commissurotomy.

BACKGROUND: Little is known concerning therapeutic modification of left atrial thrombus in mitral stenosis and its formation after successful balloon valvuloplasty (percutaneous transvenous mitral commissurotomy [PTMC]). OBJECTIVE: To test the roles of the clinical use of anticoagulant therapy and PTMC, serial changes in left atrial thrombus were examined by transesophageal echocardiography in 80 patients with mitral stenosis. RESULTS: No difference in embolic history, New York Heart Association functional class, cardiac rhythm, left atrial size or mitral valve area was found between patients with (n=23) and without (n=57) left atrial thrombus. Diuretic use was the prevalent factor for left atrial thrombi, which were dissolved completely in seven (30.4%) and partially in eight (34.7%) of the patients by adequate warfarin. However, after PTMC (n=53), newly formed thrombus was observed in four of 51 (7.8%) patients, which correlated with left atrial size (at least 50mm), atrial fibrillation and poorly controlled warfarin (thrombo test: 63.8 +/- 18.8% versus 35.9 +/- 17.7%, P<0.005). The newly formed thrombi were dissolved within several weeks. CONCLUSION: Left atrial thrombus in symptomatic mitral stenosis exhibits elusive characteristics and should be strictly monitored even after successful PTMC by transesophageal echocardiography in order to achieve adequate anticoagulation.

Atrial Function, Left↗
PubMed1996

Synthesis of a glioma-related ganglioside, O-Ac GM3 having 3-O-Ac ceramide and its substrate property toward hydrolases.

An O-acetyl group was selectively introduced into the ceramide moiety at the C-3-O on ganglioside GM3 containing N-acetyl neuraminic acid, the product of which has been previously found in rat glioma tissue as a glioma-associated ganglioside. The introduction of the acetyl residue involved a two-step process involving per O-acetylation of GM3 and saponification with a mild alkaline solution in a bilayer system constituted of water and water-immiscible organic solvent. Of the several solvents studied, 2-pentanol and diethyl ether gave the highest yields (68% and 62%, respectively). The chemical structure of the synthesized 3-O-acetyl GM3 was confirmed by proton nuclear magnetic resonance spectroscopy and fast atom bombardment-mass spectrometry, as well as by comparing the mobilities on thin-layer chromatography of its exoglycosidase-digested products with those of the synthesized, authentic 3-O-acetyl-lactosylceramide and ceramide. Furthermore, the substrate specificities of both 3-O-acetyl GM3 and 3-O-acetyl sphingomyelin toward exo- and endo-hydrolases were examined, revealing that they were hardly cleaved by the endoglycoceramidase and sphingolipid N-deacylase for the 3-O-acetyl GM3 and by sphingomyelinase for 3-O-acetyl sphingomyelin. Thus, the enzymes were found to recognize a free C-3 hydroxyl group on ceramide.

Acetylation↗
PubMed1995

Novel modification of ceramide: rat glioma ganglioside GM3 having 3-O-acetylated sphingenine.

A novel O-acetylated GM3 containing 3-O-acetyl 4-sphingenine was isolated with one having a non-acetylated base from transplanted rat glioma tissue. The presence and position of the acetyl group were estimated by one- and two-dimensional proton nuclear magnetic resonance, and fast atom bombardment-mass spectrometries. In addition, the O-acetyl GM3 showed higher immunological activity toward anti-melanoma antibody in the presence of non-acetylated GM3 in complement-dependent liposome lysis than did non-acetylated or acetylated GM3 alone in the liposome, suggesting enhancement of immunological reactivity of the intact tumor cells by a small amount of O-acetyl GM3.

Animals↗
PubMed1995

[Studies on atrial arrhythmias in atrial septal defect. The influences of aging on atrial fibrillation].

Clinical characteristics of aging in congenital atrial septal defect (ASD) without significant right-to-left shunt (> 10%), were examined especially focusing on atrial arrhythmias such as atrial fibrillation (Af) and atrial premature contraction (PAC) in serial 48 patients, aged 42.6 +/- 2.3, ranging 16-67 years, Af was found in 12 (25%) out of 48 patients. Comparing patients with Af and those without Af, the average age (52.8 +/- 2.6 vs 38.6 +/- 2.8 years, p < 0.05), functional class of New York Heart Association (2.0 +/- 0.2 vs 1.6 +/- 0.1, p < 0.05) and left atrial dimension (41.4 +/- 1.1 vs 34.7 +/- 1.2 mm, p < 0.01) were significantly higher in the patients with Af than those without Af. Hemodynamic variables, i.e., mean right or left atrial pressure, Pp/Ps, Qp/Qs, left-to-right shunt, electrocardiographic R/S ratio in the lead V1 and tricuspid regurgitation had no relation either with aging or Af. Furthermore, daily PAC counts on Holter electrocardiograms significantly correlated with the age of the patients (r = 0.642, p < 0.05). These results suggest that the incidence of Af in congenital ASD is significantly related with aging/duration of ASD, but not with hemodynamic variables.

Adolescent↗
PubMed1995

[Prediction of left ventricular functional recovery in patients with acute myocardial infarction using single photon emission computed tomography with thallium-201 and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid].

The relationships between myocardial perfusion, fatty acid metabolism, and cardiac function were investigated using dual single photon emission computed tomography (SPECT) with thallium and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid (123I-BMIPP) during the acute (10 +/- 1 days) and recovery (60 +/- 14 days) phases in 29 patients with acute myocardial infarction. There were 18 patients who underwent successful primary coronary angioplasty (PTCA group) and 11 patients who received conservative therapy (non PTCA group). Thallium and BMIPP uptakes were scored visually by a 4-point system and left ventricular ejection fraction (LVEF) was calculated by radionuclide ventriculography. Although significant positive correlations between thallium and 123I-BMIPP scores were observed during both phases, BMIPP scores were significantly lower than thallium scores in both acute and recovery phases in the PTCA group. No significant difference in thallium and 123I-BMIPP scores was observed at the recovery phase in the non PTCA group. LVEF significantly correlated with thallium and 123I-BMIPP scores in both phases in the PTCA group. Furthermore, the difference between thallium and 123I-BMIPP scores during the acute phase significantly correlated with the improvement of LVEF during the follow-up period in the PTCA group (y = 0.92x-0.77, r = 0.65, p < 0.005). These findings suggest that mismatch of perfusion and metabolism in infarcted myocardium assessed by thallium and 123I-BMIPP SPECT is increased by reperfusion therapy and persists at least until the recovery phase of myocardial infarction. The recovery of left ventricular function depends on the extent of the mismatched uptake, indicating a predictor for functional recovery following acute myocardial infarction.

Adult↗
PubMed1995

[Quantitative assessment of myocardial viability by thallium-201 reinjection with SPECT: comparative studies with resting image in myocardial infarction].

Exercise-stress thallium (Tl) scintigraphy is a reliable diagnostic tool for evaluating the reversibility of injury to the myocardium; however, overestimation of infarcted volume has been considered as a clinical limitation, both in recent and in old myocardial infarctions. To reveal the clinical efficacy of reinjection modification, infarcted and ischemic myocardium were quantitatively evaluated by stress, reinjection, and resting image with 201Tl SPECT in 43 patients with myocardial infarction. A quite significant correlation was found in severity scores from reinjection and resting images (87 +/- 12 vs. 81 +/- 10, r = 0.85, p < 0.001), these were significantly lower than the scores from post-exercise (124 +/- 13) and 4-hour delayed (103 +/- 11) images. The fractions of reversible ischemic myocardium predicted by reinjection and resting images also correlated with each other (r = 0.55, p < 0.05) and were significantly larger than those from 4-hour delayed images. Furthermore, the degree of redistribution of myocardial perfusion observed in reinjection image showed a significant positive linear correlation with improved myocardial perfusion after coronary revascularization (r = 0.80, p < 0.001), while that from the 4-hour delayed image did not. These results suggest that the severity score of thallium reinjection method is useful for quantifying both labile and non-labile myocardium after myocardial infarction and contributes to predicting the effect of coronary revascularization therapy.

Adult↗
PubMed1994

[A case of idiopathic hypoparathyroidism associated with primary hypothyroidism and diabetes mellitus].

A 50-year-old man was admitted to our hospital for the evaluation of hypocalcemia and the treatment of diabetes mellitus. Seven months before admission, he sometimes felt thirst and polyuria, and 4 months before admission, he went to a doctor to check his blood glucose and was diagnosed as having diabetes mellitus which had suddenly developed. At that time he was treated with sulfonylurea, but his diabetic control was very poor. At the time of admission to our hospital, the patient's serum calcium (Ca) level was 5.7 mg/dl, phosphorus (P) 5.0 mg/dl, and fasting blood glucose 308 mg/dl, but urinary ketone bodies were not detected. High sensitive assay of parathyroid hormone (HS-PTH), intact PTH and C-terminus PTH concentrations were under the level of detection. TSH level was slightly high (6.1 mu U/ml) with positive antimicrosomal and antithyroglobulin antibodies but thyroid hormone levels were within normal limits. TRH test showed over-response of TSH. Based on Ellsworth-Howard test, we made the diagnosis of idiopathic hypoparathyroidism associated with primary hypothyroidism and diabetes mellitus. He was treated with insulin twice a day and reached good control, and he was also administered 1 alpha-OH-D3 and calcium lactate resulting in an increase of serum Ca level after 2 weeks. These findings suggest that this case may be a polyglandular autoimmune (PGA) syndrome type 1 reported by Neufeld, which is very rare in Japan. The type of diabetes mellitus of this case is controversial. It is, however, necessary to pay attention to the decrease of the patient's insulin-secreting activity because autoimmune disorders are accompanied by this case.

Diabetes Mellitus, Type 1↗
PubMed1994

Cholesteryl ester transfer protein gene: two common mutations and their effect on plasma high-density lipoprotein cholesterol content.

Cholesteryl ester transfer protein regulates high-density lipoprotein cholesterol (HDL-C) level, and genetic deficiency causes hyperalphalipoproteinemia (HALP). The G to A mutation in the intron 14 splice donor (I14A) has been known to be a common mutation in HALP. Recently, another mutant, D442G (Asp 442 to Gly), was ascertained. The allelic frequencies of I14A and D442G were investigated using 226 unrelated patients with HDL-C of 1.03 mmol/L (40 mg/dL) or greater. Of these, 44 had a mutation I14A and/or D442G. The I14A was found in 15, including 4 compound heterozygotes (I14A/D442G) in patients with HDL-C of 2.05 mmol/L (80 mg/dL) or greater. All I14A homozygotes (n = 5) were present in the group with HDL-C of 3.08 mmol/L (120 mg/dL) or greater, and the allelic frequency paralleled the increase in HDL-C level. D442G was identified in 33, including the 4 compound heterozygotes. Its allelic frequency appeared as two clusters, one at HDL-C around 1.79-2.03 mmol/L (70-79 mg/dL) and the other at HDL-C of 2.82 mmol/L (110 mg/dL) or greater; the latter consisted exclusively of compound heterozygotes. Allelic frequency in the general population for I14A and D442G was 0.81% and 4.62%, respectively. These data suggest that D442G is a common mutation and that, although I14A is responsible for the most severe HALP, D442G leads to a relatively smaller increase in HDL-C.

Adult↗
PubMed1994

A family with complete deficiency of plasma cholesteryl ester transfer protein activities.

A 43-year-old male with a high value of high density lipoprotein cholesterol (151 mg/dl) was found among subjects receiving annual health checks. We investigated the cholesteryl ester transfer protein (CETP) activity and conducted a family study. There was complete deficiency of CETP activities in the proband and his sister, and partial deficiency of CETP activities in his mother and daughter. Genetic analysis revealed a splicing defect (G to A point mutation) in intron 14 of the CETP gene.

Adult↗
PubMed1994

Photoaffinity labeling of lipoproteins in human cerebrospinal fluid with a heterobifunctional derivative of galactosylsphingosine.

The binding of a galactosylceramide (GalCer) analog to proteins in normal human cerebrospinal fluid (CSF) was examined by photo-affinity labeling using a radioiodolabeled 2-(p-azido-salicylamido) ethyl-1,3-dithiopropionate (ASD) derivative of galactosylsphingosine (GalSph) as a probe. The affinity-bound peptides appeared at 66, 36 and 28 kDa as radiolabeled bands. The latter two peptides, 36 and 28 kDa, were independently identified by immunostaining of the isolated peptides using biotinylated GalSph, and immobilized Avidin, and by immunoprecipitation of the photolabeled peptide, to apolipoproteins (ALPs) E and A-I, respectively. The direct binding of the GalCer analog to these apo-peptides suggested that the existence in the body fluids or the transfer between the fluids and cells of the glycolipid was related to high density lipoprotein (HDL) constructions.

Affinity Labels↗
PubMed1994

Exercise-induced STV1 elevation: a sign of right ventricular dysfunction in recent inferior myocardial infarction.

BACKGROUND: Little is known about exercise-induced electrocardiographic ST segment shift in right-sided precordial leads, especially elevated ST in patients with subacute inferior myocardial infarction. OBJECTIVE: To test the clinical significance of exercise-induced STV1 deviation with special regard to right ventricular function and right ventricular involvement. DESIGN: Sixty-eight patients with recent inferior myocardial infarction (without having a left descending arterial lesion) aged 30 to 73 years (mean +/- SD, 59.1 +/- 10.0) were investigated with respect to biventricular function observed in radionuclide ventriculography and treadmill stress electrocardiographic findings. RESULT: STV1 shift during exercise (delta STV1) had a negative linear logarithmic relationship only with the right ventricular ejection fraction (RVEF) and no correlation with the left ventricular ejection fraction (delta STV1 = 6.7604-1.7528xlnRVEF, r = 0.709, P = 0.0001). Significant STV1 elevation (delta STV1 of 0.5 mm or more) predicted right ventricular dysfunction (RVEF of 40% or less) and right ventricular infarction with sensitivities of 76% and 77%, specificities of 88% and 92%, and accuracies of 84% and 77%, respectively. Twenty patients with STV1 elevation (0.5 mm or more) showed nearly identical rest and exercise electrocardiographic findings, exercise capacities and similar stenotic lesions on coronary angiography, to 43 patients without significant STV1 elevation. Elective balloon angioplasty reduced the delta STV1 during exercise in only three of six patients (50%) with right ventricular infarction. CONCLUSION: Exercise-induced STV1 elevation may be a useful indicator of global right ventricular dysfunction and/or right ventricular infarction in the subacute phase of myocardial inferior infarction.

Adult↗
PubMed1994

[Quantification of reversible perfusion abnormality using exercise-stress thallium SPECT before and after coronary revascularization].

Reversible myocardial perfusion abnormality was quantified by bull's eye and unfolded surface mapping methods in exercise thallium SPECT before and after coronary revascularization in 47 patients with angina pectoris, including 34 patients with previous myocardial infarction (PMI) and 13 with effort angina (AP). There was no difference in the incidence or extent of myocardial ischemia between the 2 groups before revascularization. However, the ischemic scores were significantly smaller in PMI group preoperatively than the reductions of the ischemic scores after revascularization. The ischemic scores, preoperatively estimated reversible perfusion abnormality was 32%, 69% and 48% of the improvement of the ischemic score (extent score, severity score, and ischemic area, respectively). Using the 3 ischemic scores, the improvement of perfusion abnormality was well predicted in 70-89% of AP patients but 35-57% of PMI patients. Thus, quantitative analysis in stress thallium SPECT is useful for detecting myocardial ischemia and evaluating the effect of coronary revascularization. However, about a half of myocardial viability was underestimated in one third of PMI patients by the conventional exercise-stress thallium SPECT study.

Adult↗
PubMed1993

Plasma noradrenaline as an indicator of functional state in hearts with mitral stenosis: the influence of acutely reduced left atrial pressure by balloon mitral commissurotomy.

To investigate the mechanism in which plasma noradrenaline concentration (pNA) is elevated in heart failure, the effect of balloon mitral valvuloplasty was used as a model of acute manipulation of the left atrial pressure reduction in ten patients with mitral stenosis. Gorlin mitral valve area and pNA were correlated with New York Heart Association functional class and found to have a significant exponential inverse relationship with each other ([pNA, pg/ml] = 198.9 x [mitral valve area, cm2]-0.696; P = 0.003). Elevated pNA could be partially explained by a reduced cardiac index (CI) ([pNA, pg/ml] = 403.4 x [CI, l/min/m2]-0.889; P = 0.027; r = 0.495), especially in severely failed hearts, but not by pulmonary capillary wedge pressure (PCWP). However, the percent changes (% delta) of variables early after balloon valvuloplasty exhibited a paradoxical contrast; % delta pNA showing a clear negative exponential correlation with % delta PCWP ([% delta pNA] = 436.0 x [% delta PCWP + 80]-0.679 - 80; P = 0.021), but not with % delta CI. These results suggest that pNA should be considered an indicator of cardiac functional class in mitral stenosis. PNA is modulated by both cardiac index and pulmonary capillary pressure, but in different ways.

Adult↗
PubMed1993

Studies on percutaneous transvenous mitral commissurotomy using a modified transseptal approach.

A modified version of Brockenbrough's trans-septal catheterization technique was carried out in 11 patients indicated for percutaneous transvenous mitral commissurotomy (PTMC). In 8/11 (72.7%), a coiled guide-wire was successfully inserted through the foramen ovale without atrial septal puncture. The Brockenbrough needle was used merely to maintain stiffness and the orientation of the dilator. PTMC was performed with an Inoue single balloon without incident. Patent foramen ovale was found by transesophageal echocardiography prior to the operation in only 1/11 patients (9.0%); nonetheless, it proved not to be a critical factor for the success of the procedure. This procedure seems to have much potential to enable the treatment of mitral stenosis with a lowered risk to the patient, as long as it is performed with precision and caution.

Adult↗
PubMed1993

Combined administration of an IK(ATP) activator and Ito blocker increases coronary flow independently of effects on heart rate, QT interval, and ischaemia-induced ventricular fibrillation in rats.

The effects of combined administration of the ATP-dependent K+ channel opener cromakalim and the transient outward K+ current (Ito) blocker tedisamil on ventricular tachyarrhythmias, QT interval, and coronary flow were investigated in isolated rat heart (n = 12/group) subjected to 30-min regional ischaemia. When administered alone, beginning 5 min before onset of ischaemia and continuously thereafter, neither cromakalim (10 microM) nor tedisamil (3 microM) had any significant influence on the incidence of VF, although tedisamil abolished sustained VF (SVF, defined as VF lasting > 2 min). Cromakalim did not affect tedisamil's ability to abolish SVF when administered concurrently with tedisamil and had no effect on SVF when administered alone; incidences of SVF were 64, 0 (p < 0.05), 66, and 0% (p < 0.05) in control, tedisamil, cromakalim, and combined treatment groups, respectively. Occurrence of SVF was related to the width of the ventricular complex at 50% of repolarisation (QT50). Pretreatment with tedisamil widened QT50 (p < 0.05), and this effect was not attenuated by combined treatment with cromakalim. Cromakalim increased coronary flow (14 +/- 0.4 in controls versus 21 +/- 0.6 ml/min/g in cromakalim-treated hearts, p < 0.05). This effect was not reduced by coadministration of tedisamil (20 +/- 0.9 ml/min/g in hearts cotreated with both drugs). Tedisamil alone had no significant effect on coronary flow.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗