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Biomedical subjects

T Nishimura

Publications and source records attributed to T Nishimura.

At least 1,189 records · Page 66Linked to original sources

Value and limitation of gadolinium-DTPA contrast enhancement in the early detection of acute canine myocardial infarction.

This study was performed to determine whether the infarcted myocardium can be distinguished from the nuclear myocardium by gated nuclear magnetic resonance imaging (NMRI) and gadolinium (Gd)-DTPA contrast enhancement in the early hours after coronary artery ligation. Twenty-one dogs were used: three dogs with 3-hr ligation of the left anterior coronary artery (LAD) (group A); six dogs with 3-hr ligation of LAD, followed by 20-30 min of reperfusion (group B); six dogs with 6-hr ligation of LAD (group C); and six dogs with 12-hr ligation of LAD (group D). Gated NMRI was performed at the time of occlusion or reperfusion, followed by intravenous injection of 0.5 mM/kg of Gd-DTPA using a whole body NMR system. The effects of Gd-DTPA on gated NMRI could not be obtained in group A, but significant contrast enhancement after Gd-DTPA administration in T1-weighted image was obtained in four of six dogs in group B, four of six dogs in group C, and five of six dogs in group D. Then NMRI contrast that expresses the signal intensity ratio between the infarcted and normal myocardia showed a significant increase in groups B, C, and D. Thus, gated NMRI with Gd-DTPA has a limitation as to the early detection of acute myocardial infarction, such as in group A, but it may have a supplementary role in the detection of acute myocardial infarction since improved signal intensities between the normal and infarcted myocardium was obtained in groups B, C, and D.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

The precursor cells of mouse lymphokine-activated killer (LAK) cells.

Culture of mouse spleen cells with recombinant human interleukin 2 (r-IL 2) resulted in the generation of lymphokine-activated killer (LAK) cells, which could lyse a variety of tumor cells. Negative selection study using various kinds of antibodies and complement indicated that LAK precursor cells existed in both mature spleen lymphocytes and immature spleen null cells. LAK cells were also induced from lymph node cells but not from unfractionated thymocytes. However, hydrocortison (HC)-resistant thymocytes or PNA- thymocyte subpopulations were highly responsive to r-IL 2 and maturated into LAK cells after 5 day-culture with r-IL 2. Moreover, it was demonstrated that r-IL 2 allowed the induction of LAK cells from nude mouse spleen cells, but not from bone marrow cells and fetal liver cells.

Animals↗

Interleukin-2 induction, response and therapy on murine lupus lesions in the MRL/l strain.

MRL/Mp-lpr/lpr (MRL/l) mice are widely known as poor inducers of interleukin-2 (IL-2) and low responders to IL-2. It was reconfirmed that the spleen cells of MRL/l mice induced a small amount of IL-2 in vitro. In vivo experiments revealed that recombinant IL-2 (rIL-2) affected T cell subpopulations in MRL/l mice. rIL-2 decreased the numbers of Thy-1 and Lyt-1 positive cells and increased those of Lyt-23, Lyt-123 and Lyt-null cells in the thymus. It decreased the number of T cell subpopulations in the lymph nodes and spleen. These data disclosed that IL-2 might affect not only the development of T cells but also the movement of T cells among the immune organs. Some synthetic immunomodulators augmented and others suppressed or had no effect on IL-2 induction activity in the spleen of MRL/l mice. There was no correlation between the clinical efficacy of drugs on rheumatic disease and experimental IL-2 induction activity. rIL-2 and human peripheral T cell derived IL-2 (hIL-2) produced similar results in short term therapeutic experiments. When rIL-2 (1,000 U/mouse) or hIL-2 (equivalent dose) was given to MRL/l mice intraperitoneally, once a week, from 8 to 16 weeks of age, anti-double stranded DNA (dsDNA) antibody and anti-single stranded DNA (ssDNA) antibody titers had no changes. IL-2 had no effect on the renal lesions histopathologically. IL-2 induction activity was also assayed using spleen cells of the animals at the time of necropsy. The results showed that the mice treated with IL-2 had lower IL-2 induction activity than nontreated MRL/l mice. mice, an animal model for systemic lupus

Animals↗

[Regional cerebral blood flow images of single photon emission computed tomography by N-isopropyl-p-[I-123] iodoamphetamine in patients with brain tumor].

Regional cerebral blood flow (r-CBF) was studied by single photon emission computed tomography (SPECT) using N-isopropyl-p-[I-123] iodoamphetamine (IMP) in order to evaluate CBF in patients with brain tumor. Total 27 studies were carried out in 20 patient, including 8 patients with meningioma, 3 with glioblastoma multiforme, 2 with oligoastrocytoma, and 7 with other intracranial tumors. All CBF images by IMP-SPECT were obtained by using a rotating gamma camera with dual heads. In the serial scans, each scan was started at 20 minutes, 2 hours and 6 hours after intravenous injection of I-123 IMP (3 mCi). The all IMP-SPECT images were compared with cerebral angiogram, X-ray CT (plain and/or enhancement), and images of Kr-81 m SPECT and Tc-99 m SPECT. In 5 patients (4 patients with meningioma and 1 with glioblastoma multiforme) this comparative study was performed before and after surgery to evaluate the r-CBF changes surrounding tumor. The abnormal lesion on X-ray-CT was identified as hot area on CBF image by IMP-SPECT in two cases with meningioma, and in 14 cases the lesion showed cold area. Totally 80% of cases showed abnormal findings on CBF images by IMP-SPECT. The cases which showed no abnormal findings on IMP-SPECT images included 1 case with meningioma which located in frontal base, 2 with small intracranial brain tumor which was smaller than 2 cm in diameter, and 1 with pituitary adenoma. On the IMP-SPECT images scanned 2 hours after injection, hot area, which was identified in two cases with meningioma on the images 20 minutes after injection, was changed into cold area.(ABSTRACT TRUNCATED AT 250 WORDS)

Amphetamines↗

[Pre- and post-operative right ventricular functions in valvular heart diseases: the significance of noninvasive assessment].

This investigation was undertaken to evaluate right ventricular function in valvular heart diseases by calculating right ventricular ejection fraction (RVEF) from first-pass radionuclide angiography (RNA). One hundred cases of valvular heart disease were examined by RNA, 93 of whom underwent cardiac catheterization and contrast left ventriculography, preoperatively. Fifty of the 100 cases were examined by RNA; 18 by cardiac catheterization post-operatively. The results were as follows: 1. In 49 cases of mitral valve disease, there was a correlation (r = -0.75) between pulmonary artery mean pressure (PAm) and RVEF. This suggested that afterload of left atrial pressure elevation induced a decrease in RVEF. 2. Although PAm did not increase so much in aortic valve disease, RVEF decreased in some cases, especially in those having massive aortic stenosis or regurgitation. In 22 cases of aortic regurgitation which had normal PAm and a left ventricular-aortic systolic pressure gradient less than 50 mmHg, there was a correlation (r = -0.69) between the RVEF and the left ventricular end-diastolic volume index (LVEDVI). 3. Although post-operative RVEF did not improve significantly in mitral valve disease, it increased significantly in the early post-operative period in aortic valve disease. Also, the increase in RVEF and the decrease in LVEDVI seemed to correlate closely in aortic valve disease. It was speculated that pre-operative decrease of RVEF is derived from a deformity of the RV caused by pressure from the enlarged or thickened LV, and that post-operative increase of RVEF is dependent upon a decrease of LV size and volume.

Erythrocytes↗

[Laboratory and clinical studies of cefuzonam in pediatric field].

We have carried out laboratory and clinical studies of cefuzonam. The results were summarized as follows: The effectiveness of cefuzonam was estimated by a plate dilution method on 26 strains each of S. aureus, E. coli, K. pneumoniae, Salmonella spp. and P. aeruginosa and 27 strains of S. marcescens isolated from patients. The distribution of MIC's of cefuzonam against S. aureus was 0.39 approximately 1.56 micrograms/ml and the peak of the distribution was 0.39 microgram/ml. Strains of 96.2% of E. coli and Salmonella spp. were inhibited at cefuzonam concentrations less than 0.39 microgram/ml. Strains of 92.3% of K. pneumoniae were inhibited at drug concentrations less than 0.20 microgram/ml. The distribution of MIC's of cefuzonam against S. marcescens was less than or equal to 0.025 approximately 12.5 micrograms/ml and the peak of the distribution was 0.2 microgram/ml and 1.56 microgram/ml. MIC's against P. aeruginosa was 12.5 approximately greater than 100 micrograms/ml. Cefuzonam was given by 5-minute intravenous administration to 4 children and 1-hour drip infusion to 1 child at a single dose of 20 mg/kg. After the intravenous administration, mean serum levels of cefuzonam were 30.8 +/- 4.55 microgram/ml at 30 minutes, 13.8 +/- 1.83 micrograms/ml at 1 hour, 0.4 +/- 0.159 microgram/ml at 6 hours. The half-life was 1.12 +/- 0.198 hours. After the drip infusion, the serum levels of the drug were 38.7 micrograms/ml at 1 hour, 5.25 micrograms/ml at 2 hours and 0.087 microgram/ml at 7 hours. The half-life was 0.93 hour. The mean urinary excretion rate was 58.1% and 33.4% up to 6 hours after the intravenous administration and the drip infusion, respectively. Cefuzoname was effective in 4 out of 5 cases with bacterial infections. No side effect due to the drug was observed in any case.

Adolescent↗

[Pharmacokinetic and clinical studies on amikacin in neonates].

Pharmacokinetic and clinical studies on amikacin (AMK) were performed in neonates and the results obtained are summarized as follows. 1. After intramuscular injection of single doses of AMK at 3 mg/kg, peak serum levels were 6.8 micrograms/ml in a 2-day-old neonate and 7.0 micrograms/ml in a 20-day-old neonate. Serum levels of AMK in the above 2 neonates at 8 hours after injection were 1.5 micrograms/ml and 1.4 micrograms/ml, respectively, and the half-life of AMK was 3.3 hours. After intramuscular injection of single doses of 4 mg/kg of AMK, the mean peak serum level was 8.1 +/- 1.1 micrograms/ml, and half-lives of AMK were 6.1 hours in a 1-day-old neonate and 4.0 hours in a 3-day-old neonate. The mean peak serum level of AMK reached at 1 hour after intramuscular administrations at single dose of 6 mg/kg was 10.5 +/- 0.5 micrograms/ml in a 3-day and a 4-day-old neonates. Serum levels at 8 hours after administrations were 3.1 micrograms/ml and 2.8 micrograms/ml, in the 3-day and the 4-day-old neonates, respectively. Half-lives of AMK in sera were 3.9 hours in the 3-day-old neonate and 3.5 hours in the 4-day-old neonate. 2. In three 2-day-old neonates, the mean peak serum level of AMK after an intravenous drip infusion for 30 minutes at single dose of 3 mg/kg was 10.0 +/- 1.1 micrograms/ml at the end of infusion and serum levels decreased to 2.3 +/- 0.6 micrograms/ml at 6.5 hours after infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

Exstrophy of the cloacal membrane. A pathologic study of four cases.

Exstrophy of the cloaca is a rare congenital anomaly. The authors add the pathologic findings of four distinct cases reported in this article to those reported in the literature. In all cases, common anomalies were recognized. In addition, there were rare anomalies, such as single umbilical artery, vestige of the left superior vena cava, common mesenterium, calcification of the cerebellum, incomplete segmentation of the left lung, abnormal shape of the liver, and knock-knee. The embryology of this complex anomaly is difficult. It is considered that this anomalous condition results from breakdown and mesodermal invasion of the cloacal membrane.

Abnormalities, Multiple↗

[Carcinoma of the esophagogastric junction with extension to the cervical esophagus].

A 51-year-old woman with adenocarcinoma of the esophagogastric junction (E-G J), which spread from the E-G J to the cervical esophagus, is reported. Only two cases of carcinoma in the E-G J with the extension of the tumor to the upper or middle portion of the intrathoracic esophagus have been reported in the Japanese literature in the past two decades and there have been no previous reports of E-G J carcinoma with extension to the cervical esophagus. At first, the invasion to the esophagus in our case was thought to be continuous. Histological examination, however, revealed that the tumor in the esophagus was discontinuous in some portions and that the lymph vessels were remarkably invaded. These findings suggested that the extension of the tumor to the esophagus was lymphogenous metastasis.

Adenocarcinoma↗

Effect of serum on inhibition of DNA synthesis in leukemia cells by cis- and trans-(Pt (NH3) 2C1(2)).

We examined the inhibition of DNA synthesis by cis- and trans-diamminedichloroplatinum (II) (cis- and trans-Pt) in leukemia cells, YAC-1 and RADA1. The degree of inhibition by trans-Pt was about the same as that by cis-Pt in vitro in the absence of serum, but the former was much lower than the latter in vivo or in the presence of serum in vitro. Atomic absorption studies showed that the amount of trans-Pt trapped by the serum in vitro is much larger than that of cis-Pt. Therefore, the amount of trans-Pt bound to DNA in vivo must be considerably smaller than that of cis-Pt, which eventually results in the antitumor-inactive nature of trans-Pt.

Animals↗

Administration of slowly released recombinant interleukin 2. Augmentation of the efficacy of adoptive immunotherapy with lymphokine-activated killer (LAK) cells.

When recombinant human interleukin 2 (r-IL-2) was given to mice by single subcutaneous (s.c.) injection it rapidly disappeared from the blood. However, administration of slowly released r-IL-2 using mini-osmotic pumps caused a significant prolongation of serum levels of IL-2. Using a method for assaying IL-2 in vivo, it was also demonstrated that both the viability and the cytotoxicity of lymphokine-activated killer (LAK) cells could be maintained at a high level in vivo by administration of slowly released r-IL-2 rather than by a single injection of r-IL-2. In addition, we successfully treated EL4-bearing mice by combination therapy consisting of LAK cells and slowly released r-IL-2.

Animals↗