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Biomedical subjects

J Nishikawa

Publications and source records attributed to J Nishikawa.

At least 109 records · Page 6Linked to original sources
PubMed1993

[Evaluation of the safety and clinical usefulness of a new myocardial imaging agent, 99mTc-PPN1011--multicenter phase II clinical trial report].

A new myocardial perfusion imaging agent, 99mTc-1,2-bis[bis(2-ethoxyethyl phosphino]ethane (99mTc-PPN1011) was administered to 52 patients with various heart diseases each at rest and peak exercise on different days (Method A) and on the same day (Method B). The safety, optimal dosage, imaging procedures and the clinical usefulness were evaluated. No drug related adverse reactions were found. Image quality was considered adequate for diagnosis with as little as 185 MBq per injection, though the optimal dose range was 370-740 MBq. SPECT images were obtainable as early as 10 min, also until 3 hours after injection. There were no significant differences in clinical efficacy between method A and B, as well as sequential tests at rest and exercise. 99mTc-PPN1011 and 201T1 images in the same patient were compared segment by segment. Image quality of 99mTc-PPN1011 was significantly superior to that of 201T1. Analysis of images indicated that both agent were similar in diagnostic efficacy. It was concluded that 99mTc-PPN1011 is useful for myocardial perfusion imaging.

Adult↗
PubMed1993

[Evaluation of the clinical usefulness of a new myocardial imaging agent, 99mTc-Tetrofosmin (PPN1011)--a report of multicenter phase III clinical trials].

The clinical usefulness of a new myocardial perfusion imaging agent, 99mTc-1,2-bis[bis(2-ethoxyethyl)phosphino]ethane (99mTc-Tetrofosmin, (PPN1011) was evaluated in 355 patients with various heart diseases. Both 1 and 2 day protocols resulted in images that were significantly clearer than those of 201Tl. The absence of significant drug related adverse reaction supported the safety of the agent for clinical use. Regional abnormalities detected by CAG agreed with 99mTc-Tetrofosmin SPECT findings in 74% and with 201Tl SPECT in 78% of this study. Eighty-four percent of an abnormalities were detected with 99mTc-Tetrofosmin SPECT, as compared with those detected with 201Tl SPECT (88.4%). The complete concordance ratio between 99mTc-Tetrofosmin and 201Tl images in segmental analysis was 87-89% at rest and stress. Since 99mTc-Tetrofosmin SPECT was judged clinically useful in 93.2% (331/355) of the patients studied, it is concluded that 99mTc-Tetrofosmin is a promising agent for myocardial perfusion imaging. The simple labeling procedure without heating and cooling is suitable for emergency administration. Reconditioning of myocardial perfusion could be evaluated with 99mTc-Tetrofosmin injection before and after interventional therapy. These are additional features of the agent for clinical use.

Adult↗
PubMed1993

[The recent studies of myocardial blood flow and metabolism by using positron emission computed tomography].

Since the application of positron emission computed tomography (PET) for myocardium, the evaluation of myocardial blood flow, glucose metabolism, fatty acid metabolism, oxygen consumption and etc. has been performed. Especially, it has been regarded very important clinically to evaluate myocardial viability from the mismatch of myocardial glucose metabolism and blood flow. Many early myocardial PET studies were qualitative, while recently noninvasive quantitation method without arterial blood sampling has become possible in quantitating myocardial glucose metabolism or myocardial blood flow reserve. We quantitated regional myocardial glucose utilization rates (rMGU) in 114 cases during fasting, oral glucose loading, or insulin clamp to study the relation between rMGU and plasma insulin value or FFA value, the normal rMGU value during each condition and the difference of rMGU among each part of myocardium. And as to the question in which condition of FDG study was appropriate to evaluate myocardial viability, we introduced the opinion of Schelbert for oral glucose loading or insulin injection method and presented our opinion for fasting or mild insulin clamp.

Adult↗
PubMed1992

[Gd-DTPA-enhanced MR imaging of the normal facial nerve].

We performed a prospective imaging study of the normal facial nerve within the temporal bone before and after injection of Gd-DTPA. The study included 29 patients using a 1.5T superconducting unit and 40 nerves (right: 21; left: 19) were available for analysis. There was no enhancement of the facial nerve within the internal auditory canal in the entire series. However, the enhancement at the labyrinthine segment was observed in one nerve (3%); at the geniculate ganglion in seven (18%); at the tympanic segment in 18 (45%) and at the mastoid segment in 28 nerves (70%). Our results indicate that enhancement of the facial nerve in normal subjects is not a rare condition.

Adolescent↗
PubMed1992

Pseudomyxoma peritonei with progressive calcifications: CT findings.

Development of abdominal calcifications due to pseudomyxoma peritonei is rare. The authors present three cases whereby computed tomographic (CT) studies during or after chemotherapy for pseudomyxoma peritonei demonstrated development and progression of punctate calcifications in the abdomen. The clinical and CT findings of these cases are presented together with a brief review of the pertinent literature.

Adult↗
PubMed1992

Congenital absence of the portal vein.

Absence of the terminal portion of the portal vein and its intrahepatic branches was demonstrated in a 22-year-old woman with focal nodular hyperplasia (FNH) of the liver. Various imaging studies and angiography showed that the portal vein entered into the inferior vena cava just above the renal veins. The clinical and radiological features of this patient and nine previously reported cases of this entity are herein reviewed.

Adult↗
PubMed1992

[Metabolism of 99mTc-ethyl cysteinate dimer (99mTc-ECD) in blood--mainly in vitro].

Metabolism of 99mTc-ethyl cysteinate dimer (99mTc-ECD) in blood was studied mainly in vitro. When 99mTc-ECD was mixed with blood taken from 12 subjects, the octanol extraction ratio of ECD (y) decreased rapidly and the octanol extraction ratio-time profile well fitted a monoexponential curve (y = Ae-kt/1000, A, k: constant, t: time after mixing). The k value and hematocrit (Ht) were significantly correlated (k = 0.376Ht-3.27, r = 0.897, p less than 0.001), therefore, it was suggested that the majority of the enzyme which dissolves ECD exists in red blood cells. When ECD was mixed with blood, there were more hydrophilic products of ECD in plasma than those generated by the enzyme in plasma. In vivo input function of 99mTc-ECD was calculated by arterial blood sampling and octanol extraction. The duration of effective input was relatively short, which was attributed to rapid decrease of octanol extraction ratio in vivo.

Brain↗
PubMed1992

[Clinical application of 18F-FDG-PET in patients with brain death].

In order to evaluate glucose metabolism in brain death, 18F-FDG-PET scans were performed in three patients with clinically highly suspected brain death. One case was caused by head trauma and other two cases were by subarachnoid hemorrhage. All of them were in deep coma without spontaneous breathing, whose intracranial pressure was remarkably elevated up to the level of mean arterial pressure. Nineteen frames of dynamic scan were started soon after intravenous injection of 18F-FDG for one minute per frame, followed by 10 minutes of static scan which started 40 minutes after the injection. Both in dynamic and static scan, no significant intracranial accumulation of 18F-FDG was seen in all of three cases. This finding can be interpreted as the evidence that there is no significant glucose utilization from blood in the brain. This is the first report of clinical application of 18F-FDG-PET to brain death. Our results support the clinical diagnosis of brain death and 18F-FDG-PET can be of value for the assessment of glucose metabolism in patients with suspected brain death.

Adult↗
PubMed1991

Pig lens glutathione S-transferase belongs to class Pi enzyme.

Class Pi glutathione S-transferase was purified to homogeneity from pig lens cytosol. This enzyme was composed of two identical 22 kDa subunits and had isoelectric point of 8.5 from the results of SDS gel electrophoresis, gel filtration, amino acid sequence analysis and isoelectric focusing. Amino acid sequence of N-terminal 15 residues was almost identical to class Pi enzymes from human, rat and mouse. Antibody against the pig enzyme crossreacted to human glutathione S-transferase-pi and anti-rat glutathione S-transferase-P antibody crossreacted to pig enzyme.

Amino Acid Sequence↗
PubMed1991

[Bone scan "flare" in patients irradiated to formerly false negative bone metastasis].

We discuss three cases irradiated to their bone metastases. 99mTc-MDP bone scan before irradiation showed normal uptake in the lesions. In all the cases, the irradiation therapy was effective, but focal increased uptake area corresponding to the site of bone metastasis was revealed by the follow-up bone scan one to three months after irradiation. We concluded that the change of tracer uptake was so-called flare in formerly false negative lesion. The cause of this phenomenon was considered either elevation of osteoblastic activity with control of tumor or progression of osteolysis until tumor got well-controlled.

Aged↗
PubMed1991

[Intra-arterial and intraportal infusion liver scintigraphy using 99mTc-labeled colloid].

Intra-arterial infusion liver scintigraphy was performed in 11 patients with primary or metastatic liver tumor, and intraportal infusion liver scintigraphy was performed in 6 patients for prophylaxis of liver metastasis from colorectal cancer. 99mTc-Sn colloid or 99mTc-phytate was administered through the catheter of which tip was placed in the portal vein or the hepatic artery, and then liver image was obtained. When 99mTc-phytate was infused intra-arterially, significant amount of the infused tracer passed through the liver and we could not get sufficient information to assess the distribution of drug administered through the catheter. On the other hand, intraportal infusion liver scintigraphy using 99mTc-Sn colloid or 99mTc-phytate and intra-arterial infusion liver scintigraphy using 99mTc-Sn colloid revealed heterogeneity of liver uptake, tracer uptake in spleen, low uptake area corresponding to the liver tumor and high uptake area around it. The findings will be clinically useful, and these methods are thought to be helpful to confirm the satisfactory drug distribution.

Adult↗
PubMed1991

[Clinical application of 99mTc-SQ30,217 myocardial imaging--a study of pharmacokinetics and imaging time].

99mTc-SQ30217 555 MBq (15 mCi) was intravenously injected to 6 healthy subjects to study its safety, pharmacokinetics and the imaging time. Neither side effects nor abnormalities in physical findings, hemato-biochemical tests, urinary test, etc. caused by this agent were observed in any case and its safety was suggested. Radiation dose estimates over the entire body was 4.88 mGy/1,110 MBq (0.488 rad) and that over the major organs was less than 10 mGy and they were within the allowable ranges. 99mTc-SQ30217 showed biphasic disappearance curve in blood with the half-life of alpha-phase 0.02 hour and that of beta-phase 10.14 hours. 99mTc-SQ30217 was considered to show characteristic pharmacokinetics in that the myocardial accumulation was high in an early stage of the administration, but it rapidly decreased. Both heart to liver ratio and heart to lung ratio were high within 10 minutes, but they decreased after 15 minutes. As a result of SPECT imaging of 4 patients with ischemic cardiac disease, the images obtained with 99mTc-SQ30217 at an early period after the administration was as good as those with 201Tl and the appearance of defects in the images with both agents was similar. 99mTc-SQ30217 was considered to be sufficiently useful as a 99mTc-labelled agent for myocardial blood flow.

Adult↗
PubMed1990

[Thin-section computed tomography of the normal minor fissure].

The minor fissure was studied with thin computed tomographic (CT) sections (2 mm thickness, 3 mm interval) in 50 patients. It showed high density line or area in all patients. In nine patients CT sections were not obtained through the all region of the minor fissure. Of other 41 patients the fissure was complete in 12 (29%), slightly incomplete in 18 (44%), half incomplete in 7 (17%), and considerably incomplete in 4 (10%). The upper surface of the middle lobe appeared to be upwardly convex in all 50 patients. The location of the highest portion of the minor fissure was hilar in 12 (24%) of 50 patients, medial 1 (2%), anterior 0 (0%), lateral 8 (16%), posterior 3 (6%), dorsal 10 (20%), central 12 (24%), others 2 (4%), and indeterminate 2 (4%). The minor fissure was higher medially than laterally in 22 (44%) patients, and higher posteriorly than anteriorly in 40 (80%) patients. The lowest portion of the minor fissure was anterior in 20 (40%) patients, lateral in 4 (8%), and posterior 3 (6%). The anterior vein of the anterior segment of the right upper lobe (V3b) came in contact with the minor fissure in 20 (40%) patients. In 18 (90%) of these 20 patients minor fissure medial to V3b was incomplete partially. Three dimensional reconstruction image of the minor fissure improved understanding of the anatomy. Familiarity with the anatomic detail of the minor fissure and with variations in the relationships of the upper and middle lobes is useful in localization or extension of a lesion.

Adult↗
PubMed1990

Identification of germination gene of Bacillus megaterium.

Glucose, KNO3, proline and leucine initiate the spore germination of B. megaterium ATCC 12872, but not of B. megaterium ATCC 19213. In order to isolate the gene concerning germination of B. megaterium ATCC 12872, we constructed its gene library in plasmid vector, and introduced into B. megaterium ATCC 19213. We obtained a transformant whose spores differed from those of the wild type strain with respect to germinability. Spores of this transformant could be germinated by glucose, proline or leucine. The recombinant plasmid prepared from this transformant was found to carry 2 kilobase pairs fragment of B. megaterium ATCC 12872 DNA. This fragment may contain the gene encoding the protein which plays an important role in germination.

Amino Acids↗
PubMed1990

[Spore-spheroplast transformation of Bacillus megaterium].

A new method for transformation of Bacillus megaterium was developed by modification of Chang and Cohen's method. In our method, spore spheroplasts were used as recipient cells instead of the protoplasts of vegetative cells. Longer incubation (60 min) of spore spheroplasts and plasmid DNA before treatment with polyethylene glycol remarkably increased the efficiency of transformation. The frequency of transformation was about 10(4) per microgram of plasmid DNA. A shot-gun-type cloning of chromosome DNA of B. megaterium ATCC 12872 was available in B. megaterium ATCC 19213 strain by this transformation method.

Bacillus megaterium↗
PubMed1990

Structures of cepafungins I, II and III.

Structures of interesting acylpeptide antibiotics cepafungins I, II and III were elucidated by NMR spectroscopic studies and some degradation experiments. The antibiotics contain a common peptide part that consists of threonine and two unusual amino acid residues, gamma-hydroxylysine and 4-amino-2-pentenoic acid. The unusual amino acid residues compose an interesting 12-membered ring with an exocyclic N-terminus to which the threonine is connected. Different fatty acyl groups connected to the N-terminus of the threonine distinguish the three cepafungins. The major component I and minor component III are new substance, but the minor component II has a structure identical with that of the recently reported antibiotic glidobactin A.

Amino Acids↗