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Biomedical subjects

Y Imai

Publications and source records attributed to Y Imai.

At least 847 records · Page 47Linked to original sources
PubMed1991

Energy intake profile in the triathlon competition by means of cluster analysis.

The subjects were 18 male triathletes competing in the 4th Kaike Triathlon held at Tottori in 1984. Answers to a questionnaire on dietary and water intake before and during the competition were analysed. Cluster analysis using the average distance method was applied to 21 variables relating to order, age, stature, body weight, total calorie intake and each nutrient element ingested during three periods: after swimming, during cycling and during the marathon. The arrival order was clustered with stature and weight, and its similarity showed 69.7 when the first cluster formed. Age along with carbohydrate, protein or water intake during the marathon formed secondary clusters with order, stature, and weight (similarity: 60.0). In the upper place group, breakfast calories occupied the largest portion of 26.1% and the smallest portion of 17.2% during the marathon running. Furthermore the group ingested more energy than the other groups during cycling.

Adult↗
PubMed1991

[Conotruncal repair of tetralogy of Fallot under 2 years old].

From October 1985 to September 1990, a repair within the conotruncal portion of the right ventricle-Conotruncal repair-was used for the primary repair of consecutive 34 patients with tetralogy of Fallot under the age of 2 years. There were three summarized points of this maneuver: the first was non-use of the tricuspid septal leaflet for closure of the ventricular septal defect, the second was short patch infundibuloplasty with a large monocusp, and the last was total resection of the infundibular septum. Length of the patch infundibuloplasty was just 30% of the right ventricle length according to our formula: 30% of RV (cm) = 1.28 X BSA (m2) + 1.10. The VSD patch was placed between the pulmonary annulus and the ventricular septal crest, consisting of the membranous flap and the posterior extension of the trabecula septomarginalis. The right ventricular (RV) to systemic arterial pressure ratio was 0.49 +/- 0.15 (N = 33) and central venous pressure was 10.2 +/- 1.9 cmH2O (N = 33) six hours after ICU admission and 8.4 +/- 1.5 cmH2O (N = 7) 18 days after operation. RV end-diastolic volume showed no increase after operation: 105 +/- 31 before repair to 104 +/- 23% of Normal after repair in the same patients. Post-operative intubation period was 14 +/- 8 hours and hospital admission period was 17 +/- 6 days after operation. All patients were in sinus rhythm. The 28% of patients showed incomplete right bundle branch block (RBBB) and other 28% of patients showed complete RBBB.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Surgical Procedures↗
PubMed1991

[The effect of blood pressure control on the progression of chronic glomerulonephritis associated with hypertension].

It is well known that hypertension (HT) frequently develops in patients with chronic glomerulonephritis (CGN) and that HT contributes to progression of CGN. So, proper antihypertensive therapy is required in hypertensive patients with CGN. However, there is so far no consensus of optimal blood pressure (BP) level to maintain the renal function in these patients. In order to evaluate the BP control level in the patients with renal insufficiency, we investigated the transition of BP and renal function in 22 CGN patients with HT (average age 36.5 +/- 9.9 years at the first medical examination, 15 male, 7 female, total 179.5 patient-years), who receive antihypertensive therapy for more than 5 years as outpatients at the second department of internal medicine of Tohoku University Hospital between 1975 and 1990. Renal biopsy had been performed in all these patients for CGN diagnosis. During this period 7 patients came to receive hemodialysis therapy from 5 to 10 (average 7.6 +/- 2.1) years after the first medical examination. In one of these 7 patients, the rate of decline in renal function accelerated after child-birth, and one after two years interruption of treatment. The other 13 patients are currently receiving drug treatments at our hospital. As a result, in CGN patients there was an optimal mean BP (MBP) control range, that is, when MBP was controlled in this range, the rate of decline in renal function became slow, but when MBP deviated from this range it became fast (p less than 0.01). Moreover, this range changed according to the serum creatinine (SCr) concentration level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Neuroacanthocytosis. A clinical, haematological and pathological study of 19 cases.

Nineteen cases are described, including 12 cases from three different families and 7 nonfamilial cases, in which multisystem neurological disease was associated with acanthocytosis in peripheral blood and normal plasma lipoproteins. Mild acanthocytosis can easily be overlooked, and scanning electron microscopy may be helpful. Some neurologically asymptomatic relatives with significant acanthocytosis were identified during family screening, including some who were clinically affected. The mean age of onset was 32 (range 8-62) yrs and the clinical course was usually progressive but there was marked phenotypic variation. Cognitive impairment, psychiatric features and organic personality change occurred in over half the cases, and more than one-third had seizures. Orofaciolingual involuntary movements and pseudobulbar disturbance commonly caused dysphagia and dysarthria that was sometimes severe, but biting of the lips or tongue was rarely seen. Chorea was seen in almost all symptomatic cases but dystonia, tics, involuntary vocalizations and akinetic-rigid features also occurred. Two cases had no movement disorder at all. Computerized tomography often demonstrated cerebral atrophy. Caudate atrophy was seen less commonly, and nonspecific focal and symmetric signal abnormalities from the caudate or lentiform nuclei were seen by magnetic resonance imaging in 3 out of 4 cases. Depression or absence of tendon reflexes was noted in 13 cases and neurophysiological abnormalities often indicated an axonal neuropathy. Sural nerve biopsies from 3 cases showed evidence of a chronic axonal neuropathy with prominent regenerative activity, predominantly affecting the large diameter myelinated fibres. Serum creatine kinase activity was increased in 11 cases but without clinical evidence of a myopathy. Postmortem neuropathological examination in 1 case revealed extensive neuronal loss and gliosis affecting the corpus striatum, pallidum, and the substantia nigra, especially the pars reticulata. The cerebral cortex appeared spared and the spinal cord showed no evidence of anterior horn cell loss. Two examples of the McLeod phenotype, an X-linked abnormality of expression of Kell blood group antigens, were identified in a single family and included 1 female. The genetics of neuroacanthocytosis are unclear and probably heterogeneous, but the available pedigree data and the association with the McLeod phenotype suggest that there may be a locus for this disorder on the short arm of the X chromosome.

Acanthocytes↗
PubMed1991

Suppression of lipoprotein lipase in 3T3-L1 cells by a mediator produced by SEKI melanoma, a cachexia-inducing human melanoma cell line.

Production of a cachexia-inducing factor(s) by the SEKI melanoma cell line, established from a human melanoma, has been well documented. Conditioned medium from cultures of this melanoma cell line contains a factor(s) that inhibits the activity of lipoprotein lipase (LPL) in fully differentiated 3T3-L1 adipocytes. The mode of inhibition of this enzyme by the factor, i.e. its dose-dependency and time course, is very similar to that of LPL-inhibition by a macrophage-derived cachexia-inducing factor, cachectin/tumor necrosis factor (cachectin/TNF). However, the conditioned medium of SEKI melanoma cells does not contain any immuno-reactive substances reactive in enzyme-linked immunosorbent assay (ELISA) with anti-cachectin/TNF antibody, or with anti-interleukin 1 alpha or beta antibodies. This LPL-suppression factor present in the conditioned medium seems to be a peptide because of its heat-lability and apparent molecular weight of more than 25,000. The conditioned media from cultures of four other different cell lines were found to show no significant suppression of LPL activity. These results imply that SEKI melanoma cells produce a cachexia-inducing factor(s) similar to cachectin/TNF but that the molecule involved is different.

Animals↗
PubMed1991

[Fontan procedure for DORV with mitral atresia and anomalous hepatic vein connection to the left atrium--advantage of leaving right to left shunt in situ].

A 5-year-old boy with double outlet right ventricle, mitral atresia, pulmonary stenosis and anomalous hepatic vein drainage into left atrium underwent Fontan procedure leaving hepatic venous-left atrial connection. Systemic venous-left atrial connection provided enough filling volume of the systemic ventricle despite of high pulmonary resistance. Extra cardiac shunt between the systemic vein and left atrium would be the second best in fontan operation for cases with high pulmonary resistance.

Abnormalities, Multiple↗
PubMed1991

[A case report of Konno procedure for Ebstein's anomaly with subaortic stenosis after Hardy procedure and repair of coarctation and VSD].

A rare case of Ebstein's anomaly with coarctation and VSD is reported. Severe subaortic stenosis and LV dysfunction were progressed after PA banding and coarctation repair at four months old and Hardy procedure and VSD closure at five month old. Konno procedure was successfully performed with SJM 21A at one year and nine months old. Since coarctation type VSD may cause subaortic stenosis after its closure due to posteriorly deviated infundibular septum, anterosuperior margin of VSD would occasionally better to be eliminated at the time of VSD closure. This is the youngest one of Konno procedure to our knowledge.

Aortic Coarctation↗
PubMed1991

[Hemodynamic changes and ventricular function before and after Fontan procedure for univentricular heart].

Ventricular function and hemodynamic parameters before and after Fontan operation were studied in patients with univentricular heart (UVH) of left ventricular (LV) type (9 cases, ages: 6-66, mean 13 years) and right ventricular (RV) type (13 cases, ages: 6-17, mean 9 years) without atrioventricular valve regurgitation. The preoperative ejection fraction (EF) was poor and only 44% of LV type and 23% of RV type met the Choussat's criterion (EF greater than or equal to 60%). There were 2 hospital deaths each in LV type and in RV type, but their causes could not be attributed to preoperative parameters of ventricular function. In survivors, the EF reduced from 62.9 +/- 7.0% before Fontan procedure to 43.4 +/- 12.6% after the procedure in LV type (p less than .05) and from 54.5 +/- 7.0% to 47.0 +/- 9.0% in RV type (p less than .01), although the ventricular end-diastolic pressure (EDP) also reduced from 12.7 +/- 2.7 mmHg before to 6.6 +/- 1.9 mmHg after the operation in LV type (p less than .05) and 10.4 +/- 2.6 mmHg to 5.5 +/- 2.4 mmHg in RV type (p less than .05). the ventricular end-diastolic volume (EDV) also reduced from 185 +/- 35% to 126 +/- 58% of expected normal volume in LV type (p less than .05) and 173 +/- 28% to 99 +/- 18% of expected normal volume in RV type (p less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

[Real time microscopic image transmission system by using Hi-vision technique].

Using a high definition television (HDTV) technique, we have designed and developed the real time microscopic image transmission system. The department of laboratory and pathology, 500 m apart, are connected by this system on a light fiber line. It consists of an electrically controlled microscope, a HDTV camera, a HDTV color monitor, and a video transmitter on the laboratory side, while on the pathology a remote microscope controller, a video receiver, and a HDTV color monitor of 22.5 (H)-39.5(W) cm in CRT size. By monitoring real time noiseless picture, pathologists can select the objective lenses, move the stage, and adjust the focus of microscope at their own office. Three-month trial revealed that this prototype system was quite useful for prompt histo-pathological diagnosis during surgical operations. So far as we know, this microscopic image transmission system with Hi-vision TV is the first one in practical use in this field.

Microscopy↗
PubMed1991

[A case of plasma cell granuloma with good response to steroid therapy].

A 46-year-old man was admitted with complaints of fever, cough and anterior chest pain. Chest X-ray examination disclosed an infiltrative shadow in the right upper lung field and chest CT scan strongly suggested invasion of mediastinum and anterior chest wall. Therefore, steroid therapy was selected because biopsy specimen showed proliferation of fibroblasts and mononuclear cells mainly containing plasma cells with no evidence of malignancy. After steroid therapy, chest X-ray examination showed that the infiltrative shadow was greatly reduced. However, since infiltrative shadow was increased again at 3 years after the initiation of steroid therapy, right upper lobectomy was performed. Histopathological analysis of resected tumor demonstrated proliferation of mature plasma cells and fibroblasts in conjunction with minor infiltration of neutrophils and lymphocytes. At 18 months after operation, new shadows appeared in right S8 and S10 which were shown to have almost the same histological findings as the resected tumor. Steroid therapy was restarted, and then the size of shadows decreased. It is conceivable that steroid therapy is an effective therapy for pulmonary plasma cell granuloma, especially multifocal and relapsing cases.

Granuloma, Plasma Cell↗
PubMed1990

Effects of N4-behenoyl-1-beta-D-arabinofuranosylcytosine on blast progenitors of acute myeloblastic leukemia.

To determine the antileukemic effect of N4-behenoyl-1-beta-D-arabinofuranosylcytosine (BH-AC), a synthetic masked compound of 1-beta-D-arabinofuranosylcytosine, the pharmacokinetics and suppressive effect on leukemic blast progenitors of BH-AC were studied. When BH-AC was added to the suspension culture of leukemic cells, BH-AC gradually decreased in concentration in the culture media and was rapidly taken into the cellular fraction. The conversion from BH-AC to 1-beta-D-arabinofuranosylcytosine was noted in both the culture media and the cellular fraction. The concentration of 1-beta-D-arabinofuranosylcytosine converted from BH-AC in the culture medium gradually increased during 7 days of culture, although the rate of conversion was variable among the samples. BH-AC suppressed primary and secondary blast colony formation in a dose responsive manner. BH-AC also suppressed the recovery of clonogenic cells in suspension culture. The suppression by BH-AC was more prominent in secondary blast colony formation and the recovery of clonogenic cells in suspension culture than in primary blast colony formation. Secondary blast colony formation and the recovery of clonogenic cells in suspension are considered to reflect the self-renewal of blast progenitors, while primary blast colony formation is considered to reflect the terminal divisions of blast progenitors. The results obtained in the present study suggest that BH-AC is more effective to suppress the self-renewal of blast progenitors than the terminal divisions. The findings offer a theoretical basis in the utility of BH-AC in the therapy of acute myeloblastic leukemia.

Adult↗
PubMed1990

Resonance Raman study on mutant cytochrome P-450 obtained by site-directed mutagenesis.

Resonance Raman spectra were observed for the threonine-301 to serine or valine mutant as well as the wild type of rabbit liver microsomal cytochrome P-450 [laurate(omega-1)-hydroxylase] (P-450(omega-1], which were prepared through site-directed mutagenesis. The high-spin marker resonance Raman (RR) bands became similarly stronger for all the P-450s examined in the oxidized form upon addition of laurate, and the RR spectra in the higher frequency region of the oxidized, reduced and CO-adduct forms did not distinctly differ among the P-450s examined. Nevertheless, the Fe-CO stretching mode (vFe-CO) of the CO adduct exhibited an upshift for the valine mutant, suggesting positional proximity of Thr-301 to bound CO like Thr-252 of P-450cam, in agreement with the expectation from the sequence analysis. The vFe-CO band was shifted to higher frequency upon binding of normal alkyl fatty acids with C10 or longer alkyl chain but little affected by binding of shorter fatty acids.

Animals↗
PubMed1990

Metabolism of glycyrrhetic acid by rat liver microsomes-II. 22 alpha- and 24-hydroxylation.

18 beta-Glycyrrhetic acid (GA, an aglycone of glycyrrhizin) is converted to 3-oxo-18 beta-glycyrrhetic acid (3-oxoGA) in the presence of NADP+ by rat liver homogenates, but GA was converted in the presence of NADPH to two other metabolites showing lower Rf values on thin-layer chromatography (TLC) than those of GA and 3-oxoGA by postmitochondrial supernatant of rat liver. The GA-metabolizing activity in the presence of NADPH was localized in microsomes, similar to localization of GA-oxidizing activity to 3-oxoGA. The GA-metabolizing activity required NADPH as a cofactor and O2 for full activity and was inhibited with CO, suggesting the hydroxylation reaction of GA by cytochrome P450. Two metabolites (I and II, lower and higher Rf values on TLC, respectively) were purified on preparative TLC. Mass spectral (MS) analyses of II and methyl ester of acetylated I indicated the formation of monohydroxylated metabolites. On the basis of 3H- and 13C-NMR assignments I and II were identified to be 22 alpha- and 24-hydroxy-18 beta-glycyrrhetic acids, respectively. 3-OxoGA and 3-epi-18 beta-glycyrrhetic acid (3-epiGA) seem to be also hydroxylated at C-22 and C-24. A metabolite of 3-oxoGA showing a lower Rf value was also identified as 22 alpha-hydroxy-3-oxo-18 beta-glycyrrhetic acid by MS and 3H- and 13C-NMR spectral analyses. In 22 alpha-hydroxylation the best substrate was 3-oxoGA, followed by GA and 3-epiGA. On the other hand, for 24-hydroxylation the best substrate was GA, then 3-oxoGA, and 3-epiGA in order. However, 18 alpha-glycyrrhetic acid (18 alpha-GA) was a poor substrate for both 22 alpha- and 24-hydroxylation.

Animals↗
PubMed1990

The effect of 1,25-dihydroxyvitamin D3 on human osteoblast-like osteosarcoma cell: modification of response to PTH.

The influence of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on adenylate cyclase responsiveness in cultured osteoblastic cells was studied using a human osteosarcoma cell line SaOS-2. 1,25(OH)2D3 treatment had no effect on cell growth, cell protein and alkaline phosphatase activity. 1,25(OH)2D3 did not alter the basal production of cyclic AMP (cAMP) in intact cells, but the cAMP formation in response to parathyroid hormone (PTH), isoproterenol (ISO) and cholera toxin was attenuated by 1,25(OH)2D3. The response to forskolin, however, was unaffected by 1,25(OH)2D3 treatment. Islet activating protein failed to modify these 1,25(OH)2D3 effect. In cell free experiments, 1,25(OH)2D3 showed similar effect--that is, PTH and ISO-stimulated adenylate cyclase activity were attenuated, but forskolin-stimulated adenylate cyclase was unaffected. 1,25(OH)2D3 treatment had no effect on the kinetics of PTH binding to PTH receptor and on the ADP ribosylation of GTP stimulatory binding protein (Gs) in SaOS-2 cells. According to these results, 1,25(OH)2D3 appeared to change the coupling of Gs with adenylate cyclase, but does not affect receptor, Gs and adenylate cyclase themselves, nor GTP inhibitory binding protein.

Adenylyl Cyclases↗
PubMed1990

Aversive taste stimuli increase CGRP levels in the gustatory insular cortex of the rat.

Calcitonin gene-related peptide-like immunoreactivity (CGRP-IR) was surveyed immunohistochemically in the insular cortex of the rat, and the levels of insular cortical CGRP-IR were measured with the radioimmunoassay method following intraoral stimulation with various taste stimuli. CGRP-IR was localized in nerve fibers within the agranular and dysgranular insular cortices. The CGRP-IR levels in the rostral (gustatory) part of the insular cortex were increased significantly by strongly aversive taste stimuli such as quinine hydrochloride and conditioned taste stimuli (NaCl and sucrose) which animals had been taught to avoid. The results suggest that CGRP in the gustatory insular cortex is concerned with rejection or avoidance behaviors to aversive taste stimuli.

Animals↗