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Biomedical subjects

H Kawamoto

Publications and source records attributed to H Kawamoto.

At least 163 records · Page 9Linked to original sources
PubMed1992

[Myocardial imaging in acute myocardial infarction using beta-methyl-p-(123I)-iodophenylpentadecanoic acid: comparison with 201Tl imaging and wall motion].

Myocardial imaging using beta-methyl-p-(123I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial imagings with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (TL) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than TL in the subacute phase, although the uptake of BMIPP correlated with that of TL (tau = 0.82, p less than 0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase (tau = 0.50, p less than 0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and TL alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of TL and WM.

Aged↗
PubMed1992

[The influence of findings of coronary artery on myocardial salvage in acute myocardial infarction].

201Tl stress myocardial scintigraphy was performed in convalescent patients with acute myocardial infarction, to evaluate the influence of stenosis and collateral circulation of coronary artery in acute phase, on myocardial salvage in chronic phase. In 14 cases of unsuccessful coronary revascularization (complete occlusion), a complete defect of thallium imaging in chronic phase was seen in only one case of four cases with good collateral circulation, while eight of 10 cases with poor collateral circulation. In 16 cases of poor collateral circulation, six cases showed a complete defect, although the target vessel had improved to less than 75% of stenosis. However, in cases of good collateral circulation, no case showed a complete defect when the target vessel had improved to less than 75% of stenosis. The myocardial salvage is quite possible (p less than 0.05), when the coronary angiography in acute phase showed the forward flow (99% or 90% of stenosis) before coronary revascularization and/or good collateral circulation (Rentrop 2 degrees or 3 degrees).

Adult↗
PubMed1991

Effects of lithium ion on ADP ribosylation of inhibitory GTP-binding protein by pertussis toxin, islet-activating protein.

Studies were made on the effects of Li+ on ADP ribosylation of inhibitory GTP-binding (Gi) protein by islet-activating protein (IAP), pertussis toxin. The ADP ribosylation of 40-41 kDa proteins of the membranes of rat cardiac ventricular cells by IAP was reduced by the addition of a nonhydrolyzable analog of guanine nucleotide, GTP gamma S, indicating that these proteins included Gi protein. The addition of LiCl (0.5-10 mM) to the membrane fractions of the cells attenuated the ADP ribosylation of the Gi protein of the cell membranes by IAP dose-dependently. The effects of LiCl were reversible. Of the monovalent ions tested, Li+ inhibited the ADP ribosylation of the protein by IAP most strongly. The effects of LiCl (2 mM) were observed even in the presence of 150 mM KCl. Moreover, LiCl decreased the ADP ribosylation of purified Gi protein by IAP. These results support that Gi proteins are one of the targets for the therapeutic effects of lithium.

Adenosine Diphosphate↗
PubMed1991

Adenosine deaminase deficiency due to heterozygous abnormality consisting of a deletion of exon 7 and the absence of enzyme mRNA.

An adenosine deaminase (ADA;EC 3.5.4.4)-deficient B lymphoblastoid cell line BADO5 derived from a Japanese patient with severe combined immunodeficiency disease and two B lymphoblastoid cell lines, BAMO5 from his mother and BAFO5 from his father, were characterized. To identify mutations affecting ADA activity, we prepared cDNAs to ADA mRNAs of the BADO5 cell line for nucleotide sequencing. Sequence analysis of one of the BADO5 ADA cDNA clones revealed deletion of exon 7, and one point mutation of base 629 from G to A that did not affect the amino acid sequence. All clones of the BADO5 cell line so far examined showed the absence of exon 7 by Southern blotting analysis. Ribonuclease protection assay with an RNA probe spanning from exon 5 to exon 11 showed that the BADO5 ADA mRNA had a deletion of exon 7, the BAMO5 mRNA had normal length, and the BAFO5 mRNA had two species with a deletion of exon 7 and with normal length. Consequently, the patient's ADA genes resulted from one allele of the BAMO5 ADA gene that did not produce a detectable mRNA, and the other allele of the BAFO5 ADA gene producing an aberrant mRNA without exon 7.

Adenosine Deaminase↗
PubMed1991

Effects of lithium ion on the inhibitory GTP-binding protein and its coupling response.

Addition of lithium ion to the inhibitory GTP-binding (Gi) protein resulted in a decrease of its ADP-ribosylation by islet-activating protein (pertussis toxin, IAP). The possibility that this decrease was due to dissociation of the Gi protein trimer was examined. Results showed that lithium ions had no appreciable effect on either the Gi protein trimer or its dissociation into its three subunits induced by Mg2+ and GTP gamma S. Next, the effect of lithium ions on Gi protein-mediated adenylate cyclase inhibition and alpha 2-adrenoceptor in human platelet membranes was examined. Lithium ion was found to impair adenylate cyclase inhibition of alpha 2-adrenoceptor stimulation of forskolin-stimulated enzyme activities. The monovalent ion also abolished guanine nucleotide modulation (GTP shift) of agonist binding, while it had no remarkable effects on antagonist binding in alpha 2-adrenoceptor of human platelet membranes. These results suggested that lithium ion caused functional change of the Gi protein without remarkable change of its dissociation, causing modulation in a coupling between alpha 2-adrenoceptor and Gi protein.

Adenosine Diphosphate↗
PubMed1991

Clinical and histologic study of endoscopic duodenitis.

Duodenitis was investigated by endoscopy in 93 cases from among 1242 subjects. Endoscopic duodenitis was classified into three types endoscopically--reddening type, erosive type and nodular type. There was a relatively high correlation between the endoscopic and the histological diagnosis of duodenitis. Severely inflamed cases were found histologically more frequently in erosive- or nodular-type duodenitis than in reddening-type duodenitis. During the follow-up period, changes in endoscopic findings were observed more frequently, from the erosive type to the reddening type, and from the reddening type to normal. There were no cases which subsequently developed duodenal ulcers. We found a significantly high incidence of "endoscopic duodenitis" in uremic patients who had been given regular dialysis, and not in hepatic cirrhosis patients.

Adolescent↗
PubMed1991

[Quantitative evaluation of acute myocardial infarction by In-111 antimyosin Fab myocardial imaging].

For quantitative evaluation of acute myocardial infarction, In-111 antimyosin Fab myocardial imaging (InAM) was performed in 17 patients with myocardial infarction who underwent Tl-201 (TL) and Tc-99m pyrophosphate (PYP) myocardial imaging in acute phase. For calculating the infarct size, voxel counter method was used for analysis in PYP and InAM, and extent and severity score were used on bull's-eye polar map in TL. The most appropriate cut-off level ranged from 65 to 80% by the fundamental experiment using cardiac phantom. The cut-off level of 0.70 (InAM) and 0.65 (PYP) were used for clinical application of voxel counter analysis. The infarct size calculated by InAM and PYP was compared with wall motion abnormality index by echocardiography (WMAI), TL extent score, TL severity score, peak CK and sigma CK. Infarct size by InAM showed the following correlations with other indices. PYP: r = 0.26 (ns), TL extent score: r = 0.72 (p less than 0.01), TL severity score: r = 0.65 (p less than 0.05), WMAI: r = 0.69 (p less than 0.05). The infarct size by PYP did not show any correlations with these indices. Therefore, the infarct size by InAM showed better correlations with TL and WMAI than that of PYP. So InAM was considered superior to PYP for quantitative evaluation of acute myocardial infarction.

Aged↗
PubMed1991

[Coronary revascularization evaluated by thallium-201 myocardial scintigraphy: a follow-up study].

To elucidate changes with time in T1-201 scintigraphy after coronary revascularization, T1-201 stress myocardial scintigraphy was performed at least twice during the follow-up period (from one to 12 months) in 58 patients with ischemic heart disease (12 with angina, and 46 with myocardial infarction) who had undergone PTCA or A-C bypass surgery. The perfusion defects were classified in 4 grades, and scintigraphic changes over grade 1 were judged significant. We evaluated; 1) time of scintigraphic improvement after revascularization, 2) presence of reverse redistribution, and 3) assessment of coronary restenosis. Scintigraphic improvement was observed in 21 of 58 patients during a 3- to 12- month follow-up period, 7 of whom improved within one month. Reverse redistribution after coronary revascularization was observed in 8 of the 58 patients (14%), including 6 who showed scintigraphic improvement in 3 to 12 months (2 were not examined). Among 29 patients whose coronary angiogram and Tl-201 scintigram were compared, 11 had angiographic evidence of restenosis and 4 of them showed deterioration of scintigraphic findings (sensitivity 57%, specificity 68%, and accuracy 66%). In conclusion, scintigraphic improvement was observed over various periods (immediately after and up to 12 months) after coronary revascularization. Reverse redistribution appears to be a predictor of good prognosis. Coronary restenosis cannot always be reliably assessed by Tl-201 scintigraphy.

Adult↗
PubMed1991

[Diagnostic utility of 111In-antimyosin Fab scintigraphy in acute myocardial infarction: comparison with 201Tl and 99mTc-pyrophosphate myocardial scintigraphy].

To assess the diagnostic accuracy, extent, and characteristics of 111In-antimyosin Fab scintigraphy (In-AM) in acute myocardial infarction (AMI), we studied In-AM in 17 patients with AMI and compared with In-AM, 99mTc-PYP and 201Tl scintigraphy. Intensity of In-AM uptake was classified into 3 grades. Fourteen of 17 patients (82%) showed positive uptake of In-AM. The locations of infarct area diagnosed by In-AM were in accordance with those by electrocardiography. There was a good correlation between the extent score of In-AM planar and that of SPECT (r = 0.72), In-AM SPECT and Tl SPECT (r = 0.79), In-AM planar and PYP planar (r = 0.92), In-AM SPECT and PYP SPECT (r = 0.76), respectively (p less than 0.01). Thus, In-AM is a useful method for diagnosis of AMI.

Adult↗
PubMed1991

High-energy orbital dislocations: the possibility of traumatic hypertelorbitism.

In a 4-year period from 1983 to 1987, 7160 patients with blunt injuries were admitted to the Maryland Institute of Emergency Medical Services Systems Shock Trauma Center. Facial injuries occurred in 10 percent of this population. High-energy fractures (characterized by computed tomography) were seen in approximately 10 percent of these patients. In this high-energy group, five cases of high-energy orbital dislocations, some representing examples of traumatic hypertelorbitism, were observed. They represent 1.5 percent of the 342 midface fractures observed and 4.8 percent of the naso-orbital ethmoid fractures observed (105 patients). One additional patient is described who was seen at the UCLA Medical Center for late repair of the condition. High-energy impacts of the upper midface created fractures of both orbits, zygomas, and nasoethmoidal regions permitting lateral transposition, enlargement, and divergence of the orbits. Interorbital, intercanthal, and interpupillary distances were increased, criteria that confirm the diagnosis of hypertelorbitism. Fifty percent of the patients were bilaterally blind, and one patient sustained unilateral blindness.

Adult↗
PubMed1990

Simultaneous immunoenzymometric assay for antibodies against human interleukin-2 and human serum albumin in rat serum.

A simultaneous immunoenzymometric assay for anti-human interleukin-2 antibody and anti-human serum albumin antibody in rat serum was developed. Two antigen-immobilized polystyrene balls were immersed in a diluted serum sample in an assay tube and then the antibodies on the balls were made to react with a horseradish peroxidase labelled anti-rat IgG antibody in the same tube after washing. The enzyme activity of each ball was measured by fluorometry. Not only were the sensitivity (70 ng/ml each), assay recovery (100-101%), and precision (C.V. = 5-13%) comparable to those of conventional immunoenzymometric assays using one antigen-immobilized ball but the assay was also much more feasible for mass routine assays. Thus, conventional immunoassays can be replaced by this convenient simultaneous method.

Animals↗
PubMed1990

The split calvarial bone graft donor site: the effects of surgicel and hydroxyapatite impregnated with collagen.

Surgicel, which is commonly used as a hemostatic agent in clinical practice, is basically composed of oxidized regenerated cellulose. Skoog followed by Thilander and Stenstrom are credited with initially describing the use of Surgicel as a subperiosteal implant that could stimulate new bone formation in the closure of secondary palatal fistulae. Encouraged by these previous studies, we decided to investigate the effect of Surgicel and a new implant material, hydroxyapatite impregnated with collagen, on the split calvarial bone graft donor site. To do this, we used adult New Zealand White rabbits as our experimental model. Our study demonstrated histological evidence of both an increased quantity and earlier bony reformation, eventually reconstituting the surgical defect in the split calvarial bone graft donor site treated with Surgicel. Additionally, we found that this alloplastic implant material has potential in the reconstruction of the donor defect in selected patients.

Animals↗
PubMed1990

Serotype analysis of group A human rotavirus related to acute gastroenteritis in winter in Gifu city.

A total of 348 fecal specimens collected from children with acute gastroenteritis in Gifu city over three consecutive winter seasons (from November 1986 to March 1989) were examined for group A human rotavirus (HRV) by either a commercial test kit or a sandwich enzyme-linked immunosorbent assay (sandwich ELISA). One hundred twelve of the 173 group A HRV-positive specimens were further subjected to serotype determination by ELISA with four serotype-specific monoclonal antibodies to VP7 (ELISA-serotyping). Ninety-one specimens (81.3%) were successfully serotyped: 41 (36.6%) were serotype 1, 13 (11.6%) serotype 2, 27 (24.1%) serotype 3, and 10 (8.9%) serotype 4. The serotypes of the remaining 21 (18.8%) could not be determined. The predominant serotype of HRV that prevailed in Gifu city changed every winter: serotype 3 (63.4%) was most prevalent in the 1st winter, serotype 4 (42.9%) in the 2nd winter, and serotype 1 (64%) in the 3rd winter.

Adolescent↗
PubMed1990

Field emission scanning electron microscopic study on the noninfarcted myocardium after myocardial infarction.

Intracellular membranous ultrastructural changes in the noninfarcted myocardium of the left ventricle were studied by examining experimental myocardial infarction in rats with a field emission scanning electron microscope. The left coronary artery was ligated at its origin for 7 days. The resulting infarcts comprised approximately 40% of the total area of the left ventricles. In a light microscopic study, the transverse diameter of myocytes had increased to 17.1 +/- 2.9 microns in the noninfarcted myocardium, compared to 14.1 +/- 3.1 microns in the myocardium of sham-operated rats (p less than 0.01). For the scanning electron microscopic study, the specimens were processed according to the Osmium-DMSO-Osmium method. Marked morphological changes of intracellular membranous structures were found in the noninfarcted myocardium, especially in the lacelike network of sarcoplasmic reticulum which occasionally formed large flattened cisternae, and in the marked proliferation of surface caveolae. It is speculated that these early ultrastructural changes in the noninfarcted myocardium reflect an adaptation of microorganellae in the failing hearts of the rats.

Animals↗
PubMed1990

[111In-antimyosin scintigraphy on acute myocardial infarction].

Indium-111 antimyosin (InAM) scintigraphy was performed in 17 patients with acute myocardial infarction (on 15 +/- 6 days from the onset). The degree of myocardial uptake was classified into 3 groups. They were ranged from low intensity as in bone marrow to high intensity as in liver. All of 17 cases showed positive myocardial uptake including low intensity. The locations of infarction judged by InAM were in agreement with those by electrocardiography, coronary angiography (CAG), and 99mTc-pyrophosphate scintigraphy (PYP, performed on 5 +/- 2 days from the onset). In 5 cases, the uptake of InAM showed doughnuts or diffuse pattern which was occasionally observed on PYP. These cases showed myocardial uptake of 4th degree of Parkey's classification with doughnuts-like pattern on PYP, and showed involvement of left anterior descending artery on CAG. In some cases, the extent of myocardial uptake on InAM did not agree with those on PYP.

Aged↗
PubMed1990

[A well-differentiated hepatocellular carcinoma within adenomatous hyperplasia].

A 37-year-old male was admitted to hospital for jaundice and ascites. An ultrasonogram revealed a hypoechoic mass located in the right anterior inferior segment. A needle specimen of the liver was taken, and its biopsy led to a histological diagnosis of a hepatocellular carcinoma. The patient subsequently underwent an operation wherein it was found that the resected tumor that was taken was not clearly demarcated from the cirrhotic parenchyma. The histological diagnosis was an adenomatous hyperplasia. In a portion of this adenomatous hyperplasia, highly consistent hepatic cells and pseudogland formations were seen, confirming the diagnosis of a well-differentiated hepatocellular carcinoma within an adenomatous hyperplasia.

Adult↗
PubMed1990

[Evaluation of syndrome X by exercise stress thallium-201 SPECT].

Using exercise stress thallium (Tl)-201 SPECT, we studied 11 patients with Syndrome X who had anginal pain and ischemic ECG change during exercise in spite of angiographically normal coronary artery. In three patients, the initial stress image showed mild hypoperfusion in the area of ST segment depression, but the delayed image showed complete or incomplete redistribution. Eight cases showed normal perfusion. This result suggests that some patients of Syndrome X could be caused by small vessel disease.

Aged↗