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Biomedical subjects

K Hayashida

Publications and source records attributed to K Hayashida.

At least 217 records · Page 12Linked to original sources
PubMed1989

[Distribution pattern of density in lumbar vertebra studied with computed tomography: a study of histogram plot].

The bone mineral status of the cancellous bone in the lumbar vertebrae was evaluated by analysing density histograms and measuring the mean density by computed tomography. The results obtained were as follows: (a) the distribution pattern of bone density in lumbar vertebrae revealed a normal distribution. (b) high correlation coefficients between peak density (r = -0.79) or mean density (r = -0.77) and age was obtained in males, whereas peak densities in females were maintained well at ages younger than 50 years and peak densities abruptly decreased after 50 years of age. Osteoporotic vertebrae, in which multiple osteosclerotic changes were observed, had several peak densities and did not show normal density distribution pattern. These results indicated that our methods combining analysis of density histograms and measurement of mean density are useful to evaluate the bone mineral status.

Absorptiometry, Photon↗
PubMed1989

Induction of polymorphonuclear leukocyte-derived hepatocyte stimulating factor and effects on alpha 2-macroglobulin synthesis.

We investigated the kinetics of production of the hepatocyte stimulating factor (HSF) by peritoneal exudate- and peripheral circulating blood-polymorphonuclear leukocytes (PMNLs). Effects of the HSFs on alpha-2-macroglobulin (a2M) synthesis and a2M specific gene expression in primary cultured adult rat hepatocytes were also examined. Peritoneal exudate-PMNLs were collected 3 hr after the injection of alkaline-denatured casein into the peritoneal cavity of rats. Secretion of HSF into the culture medium began within 15 min after the start of incubation and practically a full secretion was noted within 3 hr. Lipopolysaccharide or other agents were not required to induce HSF from the PMNLs. Inhibitors of protein or DNA synthesis, cycloheximide, actinomycin D or puromycin, did not inhibit the secretion of HSF by rat PMNLs thereby suggesting that preformed and pooled HSF in the PMNLs was secreted during incubation. Peripheral circulating blood-PMNLs collected from a healthy man did not secrete HSF, in the absence of stimulation but did secrete HSF after vigorous agitation during incubation at 37 degrees C. The PMNL-HSF induced the synthesis of a2M and the accumulation of a2M mRNA in primary cultured rat hepatocytes. However, the effect was evident only with dexamethasone present in the culture medium. Furthermore, the effects of the PMNL-HSFs on a2M and albumin protein synthesis were reciprocal: The PMNL-HSF induced a2M synthesis, whereas it suppressed albumin synthesis.

Albumins↗
PubMed1989

[A study of adequate energy, amino acid, and carbohydrate requirements in postoperative total parenteral nutrition--the effect of branched chain amino acid (BCAA) and carbohydrate mixture of glucose, fructose, and xylitol (GFX)].

This study was performed to elucidate adequate energy and amino acid (AA) requirements for TPN patients after abdominal surgery. The effects of AA formula, rich in BCAA (30% BCAA), as a nitrogen source and the carbohydrate mixture of glucose, fructose, and xylitol (GFX = 4:2:1), on nitrogen sparing were also studied. Forty-nine patients having undergone major abdominal surgeries, were divided into 5 groups. The regimens were as follows: G1: 40kcal/kg, standard amino acid (21% BCAA) 1.5g/kg. day, G2: 40kcal/kg, 30% BCAA 1.5g/kg.day, G3: 30kcal/kg, 21% BCAA 1.5g/kg.day, G4: 30kcal/kg, 30% BCAA 1.5g/kg.day, G5: 40kcal/kg, 21% BCAA 1.5g/kg.day. Glucose was the sole carbohydrate energy source in G1 through G4. In G5, GFX was used. (1) Accumulated nitrogen balances during the week immediately after operation were significantly higher in G1 and G2 where higher energy intakes were administered than G3 and G4. (2) The nitrogen balances during the 2nd or 3rd postoperative days in G2 or G4, using 30% BCAA as a nitrogen source, were higher than in G1 or G3 respectively. (3) The changes in serum rapid turnover proteins were not significantly different among these groups. (4) The accumulated nitrogen balance in G5 tended to be higher than that of G1. These results indicate that BCAA rich amino acid formula will induce a more favorable nitrogen sparing effect than a conventional AA formula on TPN patients under surgical stress.

Adult↗
PubMed1989

[Scintigraphic assessment of patients with pulmonary thromboembolism by extent of perfusion defect and right ventricular function].

In 36 cases, severity of pulmonary thromboembolism (PTE) were determined with extent of perfusion defect (%PD) from pulmonary perfusion scintigraphy combined right ventricular ejection fraction (RVEF) from radionuclide angiocardiography. In 27 cases, follow-up scintigraphy was also done. After medical therapy, delta PD (= initial %PD-follow up %PD) was significant improved in patients with normal RVEF (greater than 38%) (19.40 +/- 15.58%: n = 15) than that in those with reduced RVEF (less than or equal to 38%) (0.00 +/- 3.9%). In follow-up studies, patients with larger %PD (greater than or equal to 40) showed poor prognosis than those with moderate or less %PD (less than 40). In conclusion, these both non-invasive indicators were proved to be useful for the evaluation not only the clinical severity but the prognosis of pulmonary thromboembolism.

Female↗
PubMed1989

[Assessment of cerebral blood flow in intracerebral hematoma using IMP-SPECT].

To evaluate cerebral blood flow in intracerebral hemorrhage, we performed single photon emission computed tomography using N-isopropyl [I-123] p-iodoamphetamine (IMP-SPECT) in 20 patients. IMP-SPECT was carried out using rotating gamma camera at 30 min, and 4 hrs after injection. The results were compared with those by computed tomography (CT). In all cases, the extent of hematoma by IMP-SPECT was larger than that of CT. All cases were divided into 3 groups according to the extent of peripheral area zone of hematoma by IMP-SPECT. There were 10 cases with initial hypoperfusion and complete redistribution (Group I), 6 with initial perfusion defect and complete redistribution (Group II), 4 with initial perfusion defect and incomplete redistribution (Group III). Group III had extensive hematoma compared to Group I. The extent of peripheral area zone of hematoma could be considered as the decreased blood flow area by increased intracerebral pressure and the amplitude of redistribution may be correlated with celler damage. In conclusion, IMP-SPECT was useful to asses the viability of peripheral zone of hematoma.

Adult↗
PubMed1989

Cardiac blood-pool scintigraphy using technetium-99m DTPA-HSA: comparison with in vivo technetium-99m RBC labeling.

We performed cardiac blood-pool scintigraphy using technetium-99m diethylenetriaminepentaacetic acid human serum albumin [( 99mTc] DTPA-HSA), a newly developed blood-pool agent, in 31 patients with various heart diseases and evaluated its clinical usefulness in comparison with the conventional in vivo 99mTc red blood cell (RBC) labeling. Excellent cardiac blood-pool images were obtained by [99mTc]DTPA-HSA method. Biodistribution studies showed higher accumulation of [99mTc]DTPA-HSA than that of 99mTc RBC in the lungs and liver, but similar count ratios of the cardiovascular blood pool to whole body between the two methods. In ECG-gated end-diastolic images, no quantitatively significant difference was observed in left ventricular target-to-background ratios between these two methods. Left ventricular ejection fraction (LVEF) calculated by [99mTc]DTPA-HSA MUGA method was correlated well with that by contrast LVEF (r = 0.91). No side effects were observed in any patient. In conclusion, cardiac blood-pool scintigraphy using [99mTc] DTPA-HSA is readily performed by single i.v. injection and useful for the assessment of cardiac function.

Adult↗
PubMed1989

[Clinical significance of right ventricular ejection fraction in cases with atrial septal defect].

Right ventricular ejection fraction (RVEF) assessed by cardiac radionuclide angiography has been applied to evaluate right ventricular function such as ischemic, valvular and congenital heart disease. Using this modality, previous reports also suggest that there is good correlation between RVEF and mean pulmonary arterial pressure (mPA) from catheterization findings in mitral valvular disease and chronic obstructive lung disease. In this study, cardiac RI angiography were performed on 33 adult patients with atrial septal defect (ASD), RVEF is not so good correlation (r = -0.42) with mPA, but in cases within pulmonary to systemic ratio (Qp/Qs) less than 2.0 limits, there is good correlation between RVEF and mPA (n = 9, r = -0.71). As a conclusion, in ASD, both afterload assessed by mPA and preload assessed by Qp/Qs decrease RVEF.

Adult↗
PubMed1989

[A case of systemic lupus erythematosus associated with meningitis, myelitis, and bilateral optic neuritis].

A 16-year-old girl was admitted to our hospital in August 23, 1986, for headache, nausea and low grade fever. Marked increases in immunoglobulin indices were found in the cerebrospinal fluid. When she was 13, she was diagnosed as having SLE and lupus nephritis. On September 9, 1986, she complained of urinary retention, and pathological reflexes were elicited bilaterally. On September 13, she complained of a sudden loss of vision (count fingers) in the right eye which worsened to a visual acuity of light perception over the next 48 hours. A visual evoked response potentials (VEP) to flash stimulation gave a loss of amplitude and an increase in latency. On September 16, she complained of a similar loss of vision in the left eye. Leakage of dye around the left optic disc was found by a fluorescein angiogram on September 26. These results indicated a diagnosis of bilateral optic neuritis. Both visual acuity returned rapidly over the following month following oral prednisolone treatment. Optic neuritis is an exceedingly rare complication in SLE. Although the visual prognosis have been fairly good in the reported cases, some have resulted in various states of blindness. As for etiology of optic neuritis in our patient, ischemic change of optic nerves due to microvasculopathy as well as slight demyelinating process were speculated by the VEP pattern.

Adolescent↗
PubMed1989

Filling out phenomenon with technetium-99m HM-PAO brain SPECT at the site of mild cerebral ischemia.

Although the distribution of [99mTc]hexamethylpropyleneamine oxime (HM-PAO) in the brain is said to be in a flow-related manner without temporal change, we present cases with leakage of [99mTc]HM-PAO (filling out phenomenon) in the delayed image of brain single photon emission computed tomography (SPECT) and clarify its clinical significance. The filling out phenomenon was observed in seven out of 21 cases of cerebrovascular disease and four cases of arteriovenous malformation. The leakage of [99mTc]HM-PAO was also confirmed by visual and semiquantitative analysis. In the pharmacokinetics of [99mTc]HM-PAO in the blood, the percent dose of plasma fraction at 4 hr was reduced to 54% of activity at 30 min. The percent dose of brain blood could be predicted as 3.36%/1 at 30 min and 2.35%/1 at 4 hr after correction with the hematocrit of the brain. The filling out phenomenon of [99mTc]HM-PAO was attributed to a significant reduction of blood activity of [99mTc]HM-PAO in the plasma. Since the initial image might mask reduced rCBF with an increase of rCBV, the late image would have an advantage in accurately evaluating rCBF from the clearance of [99mTc] HM-PAO bound to the plasma. Therefore, the filling out phenomenon of [99mTc]HM-PAO in late images of brain SPECT could show the area of mild cerebral ischemia accompanying cerebral vascular reserve.

Aged↗
PubMed1989

[Detection of multivessel disease in patients with myocardial infarct using exercise myocardial scintigraphy--usefulness of SPECT with qualitative and quantitative analysis].

The detection of multivessel disease (MVD) in patients with myocardial infarction (MI) was performed using exercise myocardial scintigraphy with qualitative and quantitative analysis, to compare the diagnostic ability of planar (PL), planar + washout rate (PL + WR), SPECT, Bull's eye + WR (BE + WR) and SPECT + BE + WR. Forty seven patients of anterior MI (SVD: DVD: TVD = 29: 8: 10) and thirty four patients of infero-posterior MI (SVD: DVD: TVD = 16: 8: 10) were reviewed. SPECT was superior to PL to detect ischemia of RCA in patients with anterior MI (50% vs. 100%) and to detect ischemia of diagonal branch in patients with infero-posterior MI (0% vs. 83%). The detection of ischemia of LCX in patients with anterior MI revealed low sensitivity in both PL and SPECT. SPECT + BE + WR showed the highest diagnostic ability to detect MVD in patients with both anterior (87%) and infero-posterior MI (82%). We conclude that SPECT with qualitative and quantitative analysis is the most useful to detect MVD in patients with MI.

Adult↗
PubMed1989

[A case of myocardial infarction with ventricular tachycardia, which had discrepancy of defect size between 123I-MIBG and 201TlCl myocardial imaging].

123I-MIBG and 201TaCl myocardial imaging were carried out in 69 years-old man who had anterior myocardial infarction with ventricular tachycardia. In planar and SPECT imaging, the defect size of 123I-MIBG was larger compared to that of 201TlCl. The zone of fractionated activity was corresponded with the defect of 123I-MIBG. Thus, the denervated but viable myocardium could be detected by 123I-MIBG and 201TlCl myocardial imaging. 123I-MIBG may give a useful clinical information, since denervation may play a role in causing ventricular arrhythmia after myocardial infarction.

3-Iodobenzylguanidine↗
PubMed1989

[Comparison of thallium perfusion and electrocardiographic findings at exercise thallium-201 scintigraphy with coronary arteriographic findings].

Findings of thallium-201 perfusion (Tl) and exercise electrocardiography (ECG) at exercise thallium-201 scintigraphy was compared with coronary arteriographic findings (CAG) in 283 patients. We classified these cases into four groups by Tl and ECG; [A] Tl(+).ECG(+), [B] Tl(+).ECG(-), [C] Tl(-).ECG(+), [D] Tl(-).ECG(-). Redistribution of thallium-201 was evaluated by qualitative (visual) analysis. Three percent of group A consisted of the patients with normal coronary artery, and thirty-eight percent of group D consisted of the patients with coronary artery disease. On exercise thallium-201 scintigraphic imagings, most of patients with normal coronary artery showed redistribution of inferior (24%) and septum (45%). On exercise electrocardiographic findings, most of patients with normal coronary artery showed ST-segment depression in II, III, aVF, V5 and V6. In patients with coronary artery disease, single vessel disease in group B was larger than that in group C (62% vs. 33%, p less than 0.05), and triple vessel disease and left main truncus disease in group C was larger than that in group B (37% vs. 10%, p less than 0.05). On exercise thallium-201 scintigraphic imagings, most of false negative in patients with coronary artery disease changed to true positive by quantitative analysis. The patients with less than 90% coronary stenosis in group C was larger than that in group B (65% vs. 100%).

Aged↗
PubMed1989

[Pericardial fibrosarcoma demonstrated by Ga-67 scintigraphy].

A case of malignant fibrosarcoma originated from pericardium was reported. A 31 year-old female who complained of general fatigue and back pain showed dilated cardiac shadow in chest X-ray. Cardiac blood pool scan with 99mTc-RBC revealed avascular mass in pericardial cavity which push the heart up and left side. It was suspected to be malignant, since the mass had increased 67Ga uptake. CT and MRI also demonstrated that the tissue characterization of the pericardial mass was irregular, and the mass compressed venous return. The large mass originated from pericardium caused the right sided cardiac failure. In 12 years ago, she had a history of operation which resected benign hemangioma in the same space (pericardium). We could suspect the malignant transformation between the two rare pericardial tumors; benign hemangioma and malignant fibrosarcoma.

Adult↗
PubMed1989

[Surgical experience with tracheoplasty].

We have had experience with 31 tracheoplastic procedures. Underlying diseases consisted of primary tumor, cancer invasion from carcinoma of the thyroid gland and the esophagus, traumatic rupture and post-tracheostomy and tuberculous stenoses. During operation, respiratory support has been satisfactorily established by using the intubation method via the operative field and/or high frequency ventilation instrument. Furthermore, development of absorbable suture material like Dexon and Vicryl benefited by minimizing granulation stenosis at anastomosis due to less foreign body reaction. The prognosis for carcinomatous involvement from surrounding organs was much worse according to advanced cancer stages. However, surgical outcome of this procedure was satisfactory in terms of relieving respiratory distress.

Humans↗
PubMed1989

[Usefulness of coronary angioplasty (PTCA) of the infarct-related artery in patients with prior myocardial infarction--follow up of infarct zone pre- and post-angioplasty by stress thallium scan].

We studied the efficacy of coronary angioplasty (PTCA) of the infarct-related artery in 29 patients with prior myocardial infarction by stress thallium scan. Twenty-seven patients had anterior myocardial infarction (single LAD disease), one had inferior (single RCA disease) and one had posterior (single LCX disease). According to the stress-redistribution thallium scintigraphic finding before PTCA, the patients were classified in 4 groups; (A): three patients with complete redistribution. (B): fourteen patients with incomplete redistribution. (C): seven patients with partial redistribution. (D): five patients with no redistribution. After PTCA, the parameters of residual ischemia in the infarct area (% RD and Thallium ischemic score = TIS) were improved significantly but those of infarct size (RD% uptake and Defect Score = DS) were improved slightly in group A. In group B and C, % RD, TIS, RD% uptake and DS were all improved significantly. In group D, TIS was improved slightly and DS was improved slowly 3 months after PTCA. Group A had high probability of viable muscle and group D had high probability of scar at the infarct zone. Group B and C showed intermediate type between group A and D. The change of infarct area after PTCA was variable in 4 groups but both residual ischemia and infarct size decreased in all groups. Thus, PTCA of infarct-related coronary artery is useful even in the patients with prior myocardial infarction.

Adult↗
PubMed1989

[Assessment of myocardial necrosis by 111In-antimyosin F ab scintigraphy].

111In-antimyosin F ab (AM) myocardial scintigraphy was carried out in (A) 13 patients with acute myocardial infarction (9.9 +/- 2.2 days from the onset) and (B) 9 with myocarditis and/or dilated cardiomyopathy. Forty eight hours after injection of AM, the patients were injected with 74 MBq (2 mCi) of thallium-201 (TL). The two sets of Planar and SPECT image were obtained simultaneously using dual energy window sets. In group A, positive focal AM uptake was demonstrated in 12 (92%) patients. Higher AM uptake was observed in patients who had PTCR/PTCA. By combination with TL, it is useful to detect inferior infarction and to differentiate old from acute infarction. Dual SPECT images gave precise information about the infarcted area. In group B, positive diffuse AM uptake was demonstrated in 7 (77%) patients. In conclusion, AM myocardial scintigraphy was proven to be useful for the assessment of acute necrosis after myocardial infarction but also on-going necrosis of myocarditis and/or myopathy.

Adult↗