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Biomedical subjects

K Imai

Publications and source records attributed to K Imai.

At least 883 records · Page 49Linked to original sources

Antioxidative effect of protoporphyrin and increase of glutathione in protoporphyrin-administered rat liver.

The effect of protoporphyrin (PP) administration on the activities of enzymes related to and/or involved in lipid peroxidation and on the content of reduced glutathione (GSH) was investigated in rat liver. PP, at an intravenous dose of 20 mg/kg, increased GSH content, caused a weak suppression of NADPH-cytochrome c reductase activity and a slight increase of gamma-glutamyl transpeptidase activity 24 h after dosing, but had no effect on the activities of other enzymes such as xanthine oxidase, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase, gamma-glutamylcysteine synthetase or glutathione synthetase. Treatment of rats with diethyl maleate following PP injection resulted in the disappearance of antioxidative action of PP. Furthermore, sinusoidal, but not canalicular, efflux of hepatic GSH was decreased by the PP treatment. The increase of liver GSH content by PP treatment due to the decrease of sinusoidal efflux of GSH from the liver, thus would be involved in the exertion of antioxidative action of PP.

Animals↗

Usefulness of thallium-201 re-injection method for the evaluation of myocardial viability.

Areas of the heart which are supposedly absent of myocardial viability due to persistent thallium defect in exercise thallium myocardial scintigraphy sometimes recover ventricular wall motion through coronary revascularization. To avoid such underestimation of myocardial viability, a "re-injection method" was developed. At the peak of supine ergometer exercise in 51 patients with coronary artery disease, 111 MBq thallium was injected. Conventional exercise and 3 h-delay images were then obtained using single photon emission computed tomography. Subsequently, 55 MBq thallium was injected and a re-injection image was obtained 1 h later. Each image was divided into 12 segments and compared by left ventriculography and coronary angiography. Redistribution was found in 36 patients (71%) on the delayed images and in 44 patients (86%) on either the delayed or the re-injection images (p < 0.05). There were 127 redistribution segments (38%) on the delayed images and 163 (49%) on the re-injection images out of 336 defects on the exercise images (p < 0.001). In normokinetic segments with significant coronary stenosis and in hypokinetic segments, redistribution was found in 42% and 45% of the defects, respectively, on the delayed images, and in 65% and 62% of the defects, respectively, on the re-injection images (p < 0.01). However, no significant differences were observed between the delayed and either the delayed or re-injection images in the akinetic segments. These results suggest that the re-injection method is useful for avoiding underestimation of myocardial viability.

Aged↗

Assessment of ejection fraction of the right and left ventricles in patients with acute myocardial infarction by magnetic resonance imaging.

Right and left ventricular function in acute myocardial infarction (AMI) was assessed by ECG-gated magnetic resonance imagine (MRI) in 64 patients and 8 volunteers. Five short axis images for intrinsic cardiac long-axis of the left ventricle were obtained at 9 msec and 309 msec after the R wave as end-diastole and end-systole. Right and left ventricular volumes were measured by Simpson's rule. The intraobserver variabilities in right and left ventricular ejection fraction (RVEF: r = 0.94, LVEF: 0.89) were excellent. The interobserver variabilities in RVEF (r = 0.61) and LVEF (r = 0.77) were fair. LVEF, but not RVEF, was significantly reduced in patients with AMI. Among left ventricular dysfunction (LVEF < or = 40%) patients, 50% exhibited right ventricular dysfunction (RVEF < or = 40%). Among patients without left ventricular dysfunction, only 12% exhibited right ventricular dysfunction. In left ventricular and biventricular dysfunction compared with control, the left ventricular end-diastolic volume index increased (65 +/- 10 ml/m2, 68 +/- 12 ml/m2 vs 54 +/- 8 ml/m2), the end-systolic volume index increased (40 +/- 16 ml/m2, 43 +/- 7 ml/m2 vs 18 +/- 1 ml/m2), and the right ventricular end-diastolic volume index decreased (52 +/- 13 ml/m2, 53 +/- 20 ml/m2 vs 65 +/- 8 ml/m2). MRI can thus be used to assess ventricular systolic function. Since patients with left ventricular dysfunction revealed a high incidence of right ventricular dysfunction, an interaction between the left and right ventricles may occur in ventricular dysfunction.

Adult↗

Relationship of anthropometric indices of body fat to cardiovascular risk in Japanese women.

The relationship between body fat indices and cardiovascular risk was analyzed in 97 Japanese women aged 36-72 years. The variables used were anthropometric measures of body fatness, blood lipids and blood pressure. Total adipose tissue weight (TATW) was estimated from bioelectrical impedance measurements. Subcutaneous adipose tissue weight (SATW) was calculated by measuring subcutaneous fat thickness at 14 sites using a skinfold caliper. The indices of body fat distribution were the ratios of waist to hip circumference (WHR) and abdominal to hip circumference (AHR). Blood pressure and serum lipid levels were determined in all subjects after an overnight fast. The correlations among the various body fat indices were high, and all were strongly correlated with WHR and AHR; only % SATW and percentage internal adipose tissue weight (%IATW) were not correlated with WHR and AHR. Significant positive associations were found between WHR, triglycerides and systolic blood pressure (SBP). Negative associations were found between WHR and HDL-cholesterol (HDL-ch.) and the ratio of HDL-ch. to total cholesterol (HDL-ch./T-ch.). On the other hand, significant positive associations were found between AHR, T-ch., LDL-cholesterol, free fatty acid and SBP. A negative association was found between AHR and HDL-ch./T-ch.. Partial correlations were used to determine further associations between cardiovascular risk factors and fat distribution indices. SBP was associated with WHR or AHR after removing the effects of age. Similarly, HDL-ch./T-ch. was associated with WHR or AHR after removing the effects of age and degree of obesity (BMI). These results suggest that the WHR and AHR are equally valid estimates of body fat distribution with respect to their relationship with cardiovascular risk. These relationships occurred independently of age or BMI in Japanese women. These findings emphasize the importance of intra-abdominal obesity as a metabolic risk factor for cardiovascular disease associated with a high WHR and AHR.

Adipose Tissue↗

[The effect of aerobic exercise training on internal body fat in obese women].

A group of 11 obese women (from 13% of ideal weight and higher) volunteered to participate in a study designed to reduce weight in a 92-day program of aerobic exercise. Before and after the weight reduction period, body fat indices were measured by deuterium oxide (D2O) dilution and by skinfold anthropometry. Changes in internal body fat and subcutaneous fat were calculated. Mean weight loss was 3.6 +/- 1.2 kg, and internal body fat and subcutaneous fat were 1.8 +/- 1.3 kg (21.2%) and 3.0 +/- 0.9 kg (16.0%), respectively. Highly significant correlation were obtained between changes in internal body fat and total body fat (r = 0.856, p < 0.001). However, changes in internal body fat were not significantly associated with changes in waist to hip ratio (WHR). In the present study, we found that changes in total body fat were significantly related to changes in internal body fat during treatment of obesity with aerobic exercise. However, changes in internal body fat were not valid estimates of changes in body fat distribution in relation to changes in WHR.

Adipose Tissue↗

Soluble ICAM-1 levels in serum during acute infectious mononucleosis.

Intercellular adhesion molecule-1 (ICAM-1) has been reported as a T-cell, B-cell or macrophage/monocyte activation antigen. We investigated whether soluble ICAM-1 levels in serum increased during the acute stage in 11 patients with infectious mononucleosis (IM). Serum ICAM-1 levels were measured by a double determinant immunoassay using 2 monoclonal antibodies in the FAST system. Serum ICAM-1 levels in patients with IM increased during the acute stage. There was a positive correlation between serum ICAM-1 levels and absolute counts of peripheral blood mononuclear cells. Our results suggest that the elevated serum ICAM-1 levels are based on the increased counts of activated peripheral blood mononuclear cells and that ICAM-1 is a part of the regulatory system of immune reactions during acute IM.

Acute Disease↗

[Immunological study on Alzheimer's disease using anti-beta-protein monoclonal antibodies].

Monoclonal antibodies (TB1 & TB2), which were obtained by immunization of 24 amino acids in BALB/c mice, bound specifically to the amyloid senile plaque and amyloid-angiopathic lesions of brain tissues of patients with Alzheimer's disease (AD) or with senile dementia of Alzheimer type (SDAT), and strongly reacted with the 1st part (Asp-Ala-Glu-Phe-Arg-His-Asp) of beta-protein. Western blotting and two-dimensional immunoelectrophoresis of cerebrospinal fluid (CSF) and serum revealed bands of 125 and 20 kilodaltons. The positive frequency of 125 and 20 KD bands detected by two-dimensional immunoelectrophoresis was higher in the serum of AD and SDAT patients (12 cases) than in that of normal control patients. ELISA employing various anti-amyloid precursor protein (APP) antibodies was performed using the extract of the human neuroblastoma cell line (NB39) which produces APP. In the near future, we hope to measure APP in CSF and sera from patients with Alzheimer's disease.

Aged↗

[The clinical significance of carbohydrate antigen 19-9 (CA19-9) in transitional cell cancer of urinary tract].

For the purpose of evaluating the utility of CA19-9 determination in transitional cell cancer (TCC) of the urinary tract, its serum value, tissue level and, immunohistochemical study, and follow up study, with high serum value were examined in 43 cases with TCC and 13 cases of control. 1. Serum values were 19.1 U/ml in the control group and 198 U/ml in the tumor group. Though those of tumor were higher than those of the control group, there is no statistical difference between both groups. The cases with abnormally high value were observed in 13.7% of the control group, 13.8% of the bladder cancer, and 57.1% of the upper urinary tract cancer. 2. Tissue levels were 816 U/g wet tissue in the control group and 13,000 U/g wet tissue in the tumor group, showing a significantly higher value (p < 0.01) in the tumor group, statistically. 3. Immunohistochemical study were positive in 4.0% of the control group and 88.4% of the tumor group. 4. There is a significant correlation between serum values and tissue levels (p < 0.05, r = 0.483). 5. The serum values did not correlated with the staining property, tumor size, grade, and stage. 6. The tissue levels correlated with the tumor size, but did not correlate with the staining property, grade, and stage. 7. In the follow-up study of cases with high value, those, who had not attained postoperative normalization, died of recurrent carcinoma. In cases showing an elevation despite postoperative normalization, too, all showed recurrence. Only those, whose value were normalized and remained at the normal range, are living without metastasis.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Tumor-Associated, Carbohydrate↗

[Investigation on recurrent and evolutionary factors in superficial bladder cancer].

To evaluate clinical and pathological factors responsible for tumor recurrence, disease progression and upper urinary tract reoccurrence, we reviewed data from 244 patient with superficial bladder cancer (pTa and pT1) who were initially treated by bladder sparing operation between 1961 and 1990. The factors assessed in the present analysis included sex, age, interval between initial symptoms and first consultation, presence of hematuria, bladder irritability, tumor shape, tumor base configulation size, number, grade, stage, initial treatment, bladder instillation and medication. Accumulated recurrence rates were 13% for the first year, 20% for the second year, 23% for the third year and 28% for the fifth year. Tumor base configulation, number and grade demonstrated significant difference among each category. Multivariate analysis by the Cox's proportional hazards model confirmed that tumor number was the most important factor, followed by grade in this order. Disease progression developed in 7 patients (3%) and number and grade of tumor demonstrated significant difference. Progression was noted in 60% of multiple, G3 and pT1 tumor. Upper urinary tract recurrence developed in 5 patients (2%), however, we can find no risk factor for upper urinary tract recurrence.

Adult↗

[Screening examination for prostate cancer. Early detection and mass screening].

The significance of symptoms, digital rectal examination (DRE), transrectal ultrasonography (TRUS) and prostatic specific antigen (PSA) as aids in the early detection of prostate cancer was investigated. In number of studies, sensitivity of DRE is lower than that of TRUS but specificity of DRE is adversely higher than that of TRUS. PSA was an excellent means to observe clinical course of prostate cancer patients but have proven to be insensitive and nonspecific to detect early stage prostate cancer. There is certainly no single test that can be applied reliable to detect the presence of prostate cancer at present. The use of three screening modalities must be recommended to improve the detection rate. Mass screening program in Gunma Prefecture has been being studied since 1981. In this paper, we demonstrated that this screening program is successful to detect early prostate cancer with high detection rate (0.8%), improves the survival rates comparing to those of patients detected by outpatient clinics and the tests applied in this program prove relatively high specificity and sensitivity. To prove the significance of mass screening program, pilot studies in well executed randomized prospective protocols are urgently needed. To achieve this purpose, it is necessary to organize a cooperative study group since approximate 50,000 to 100,000 subjects should be examined in this protocol.

Aged↗

[Ultrasonic diagnosis of renal cell carcinoma in hemodialysis patients].

Abdominal ultrasonic examination (US) was performed in 1556 patients on hemodialysis for 7 years and 6 months from April 1955 to September 1992. Renal cell carcinoma (RCC) proved histologically by operation was found in 36 patients (41 kidneys). Among the 36, RCC developed from the contracted kidney in 15, the individual kidney after renal transplantation in 3, and from ACDK (acquired cystic disease of the kidney) in 18. Among the 18 (ACDK), multiple tumors were found in the unilateral kidney in 8 and in bilateral kidney in 5. RCC was detected at the rate of 2.3% in patients on hemodialysis (1 out of 43). It was 29 time as high as in healthy persons (RCC was found in 22 out of 27933 at our Health Check-up Center, 0.079%). RCC was diagnosed 100% by US, 68% by CT, and 55% by angiography. US is the most excellent examination for the diagnosis of RCC in patients on hemodialysis.

Abdomen↗

[Symptoms and signs of benign prostate hypertrophy (BPH)].

Clinical characteristics of BPH were investigated in the relationship among prostate volume estimated by transrectal sonography, symptoms by questionnaire, residual urine volume, and voiding force evaluated by uroflowmetry. There was no apparent relationship among them, which might be caused by the poor reproducibility of residual urine volume, the difficult enumeration of the symptoms, contamination of other diseases of which voiding disorder is correlated with aging and other unknown factors. Under such a situation, this disease should be treated as a BPH syndrome. Moreover we propose that BPH syndrome should be classified into three types; type 1: symptomatic BPH without enlarged prostate, type 2: asymptomatic BPH with enlarged prostate and type 3: symptomatic BPH with enlarged prostate.

Aged↗

[Measurement of serum PSA by DELFIA PSA kit and its application for mass screening. The Gunma Urological Oncology Study Group].

The significance of prostate specific antigen (PSA) measured by DELFIA PSA kit in the 1,177 serum samples examined by mass screening for prostate cancer was evaluated. All subjects were examined by questionnaire, digital rectal examination (DRE) and prostatic acid phosphatase (PAP) and the subjects in whom prostate cancer was suspected from abnormal DRE and/or elevated PAP were recommended to receive the secondary screening for the presence of prostate cancer. All serum specimens used for this study were kept in our serum bank. The cut-off value was investigated between non-cancer subjects (diagnosed as normal, voiding disturbance or BPH) and prostate cancer patients. When the cut-off value was 2.89 ng/ml, the sensitivity, specificity and accuracy as prostate marker was 80.6%, 90.0% and 89.4%, respectively. Therefore, the cut-off value was determined as 3.0 ng/ml. The significance of PSA was retrospectively evaluated compared to PAP in the subjects examined by our mass screening. Twenty eight of the 39 palpable prostate cancers which could not be detected from the PAP level were detected from the PSA level, namely the sensitivity of the detection using the PSA level is more excellent than that using PAP. However, the false negative rate obtained using PSA was high (30.3%) in the patients with stage B disease. The relationship among serum PSA concentration, prostate size estimated by DRE and age was investigated. PSA was increased with age and prostate size. This estimation should be confirmed by using an ultrasonography because the prostate size obtained by DRE is inaccurate as compared with that obtained by ultrasonography.

Adult↗

Expression of intercellular adhesion molecule-1 on transitional cell cancer. Possible significance in immunity against tumor cells.

Immunohistochemical examination demonstrated expression of intercellular adhesion molecule-1 (ICAM-1) on 17 of 44 transitional cell cancers (TCCs) but not on normal transitional cells. ICAM-1 was frequently expressed in higher stage tumors, especially in those with abundant immune cells scattered within tumor. Analysis of infiltrating immune cells showed that they were composed mainly of T lymphocytes and a smaller number of macrophages bearing the lymphocyte function-associated antigen-1 (LFA-1). Expression of ICAM-1 on transitional cell cancer cell lines was augmented by in vitro treatment with interferon-gamma, tumor necrosis factor-alpha, and interleukin-1 beta. Furthermore, Northern blot analysis revealed higher quantities of a 3.3-kb RNA in T24 cells exposed to interferon-gamma or tumor necrosis factor-alpha. These results suggest that the expression of ICAM-1 on transitional cell cancers might be modified by cytokines produced by infiltrating immune cells, which might facilitate immune responses against cancer cells.

Aged↗

[Two cases with acquired immunodeficiency syndrome in our hospital].

We report two cases of AIDS whom we have recently experienced. One patient was a 54-year-old man who admitted our hospital due to third degree burn. In this case, we did not know whether or not he was suffered from AIDS, when he was delivered by the ambulance. In autopsy, pneumocystis carinii pneumonia and renal tuberculosis were found in addition to marked decrease of T cells in lymph nodes. The other patient was a 40-year-old man with remarkable symptoms of central nervous system. Route of infection of HIV is unknown. He had dementia, left hemiplegia, bulbar palsy, progressed to rigid decorticate posture and died of respiratory arrest due to involvement of the brain stem, despite of treatment including use of 3'-azido-2',3'-dideoxythymidine (AZT). Magnetic resonance (MR) images showed progressive cerebral atrophy and a diffuse high signal intensity area of cerebral white matter on T2-weighted MR images, suggesting the diagnosis of HIV-induced encephalopathy.

Acquired Immunodeficiency Syndrome↗

[Study of risk factors for prostatic cancer].

A case-control study was conducted on 294 prostatic cancer patients and controls. General population controls were chosen from 13 areas in Gunma Prefecture and were matched by age (+/- 2 y.o.) to cases. Odds ratio (O.R.) and 95% confidence interval (C.I.) were calculated on each item according to group; 69 years old or younger and 70 years old or older, and age-adjusted O.R. and 95% C.I. were calculated. Risk factors of prostatic cancer were investigated. There was a significantly higher risk for prostatic cancer in those 1) engaged in agriculture, forestry or fishery (< or = 69, > or = 70, total), 2) shaving 1/3 days or less frequently (> or = 70, total), 3) having thin pubic hair (total), 4) phimosis (< or = 69, total), 5) having history of smoking (> or = 70, total), 6) history of smoking 50 years or more (total), 7) having eaten vegetables rarely (> or = 70, total), 8) having past history or complication of asthma (> or = 70). O.R.s of having past history or complication of benign prostatic hypertrophy, prostatitis and urethral stricture were high significantly, but they were supposed to be caused by bias. Four patients had first degree family members who suffered from prostatic cancer, compared to zero in the control. There was a significantly lower risk for prostatic cancer in those 1) engaged in office work (> or = 70, total), 2) blood type A or AB (< or = 69), 3) having had one child or none (total), 4) having past history or complication of tuberculosis (total).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Rupture of a giant renal artery aneurysm: report of a case.

We report a case of rupture of giant renal artery aneurysm (10 cm diameter) with lower abdominal discomfort and a syncopal attack. The patient was successfully treated by nephrectomy. Rupture of a giant renal artery aneurysm is lethal in most cases and prompt diagnosis is indispensable. As preoperative diagnosis, ultrasonography was useful as it showed the blood flow in the renal artery aneurysm in real-time. CT scan was also useful in determining accurately the size of the aneurysm and extension of hematoma in its surroundings.

Aneurysm, Ruptured↗

[Usefulness and safety of dobutamine stress thallium myocardial scintigraphy].

Pharmaceutical stress test is performed for diagnosis of coronary artery disease in patients who can not perform exercise test. We studied whether high dose dobutamine stress test is useful and safe. Subjects consisted of 133 patients (pts) in doubutamine stress test and 45 pts in exercise test. Dobutamine stress test was initiated by 10 micrograms/kg/min, followed by 10 micrograms/kg/min increment every 3 minutes. Maximal doubutamine dose was 40 micrograms/kg/min for 3 minutes. Endpoints of dobutamine stress were as follows: ST depression equal to or more than (> or =) 0.2 mV: 30 pts, > or = 75% predictive maximum heart rate: 20 pts, > or = 20 mmHg systolic blood pressure fallen: 10 pts, 40 micrograms/kg/min for 3 minutes: 10 pts, chest pain: 7 pts, pressure rate product (PRP) > or = 25,000: 1 patient. Side effects of dobutamine stress test were as follows: palpitation: 52%, arrhythmia: 13%, angina and dyspnea: 7%, headache: 6%. These symptoms were disappeared within 2 minutes. One patient, who performed dobutamine test 2 day after PTCA, had myocardial infarction. At peak of dobutamine stress test, systolic blood pressure, heart rate and PRP were increased similar to exercise test. However, diastolic blood pressure was not changed. The concentration at peak of dobutamine was 25.5 +/- 7.8 micrograms/kg/min. The duration of dobutamine stress test was 7.3 +/- 2.3 minutes. The 65 patients (49%) need more than 20 micrograms/kg/min of dobutamine which was maximal loading dose in previous reports. For diagnosis of coronary artery disease, sensitivity was 91% (31/34) and specificity was 70% (7/10). From these data, high dose dobutamine stress test is useful and relatively safe stress method for diagnosis of coronary disease. This stress test would be performed in patients who can not perform exercise test.

Adult↗