PubMed Health⌕ Search

Biomedical subjects

I Sakurai

Publications and source records attributed to I Sakurai.

At least 19 recordsLinked to original sources
PubMed1996

Inhibitory effect of fluvastatin at doses insufficient to lower serum lipids on the catheter-induced thickening of intima in rabbit femoral artery.

The anti-atherosclerotic effect of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors at doses insufficient to lower serum cholesterol was investigated in rabbit femoral artery denuded by balloon catheter. Fluvastatin and pravastatin were given orally at doses of 4 and 8 mg/kg per day, respectively, for 2 weeks after the catheterization. There was little change in serum cholesterol, triglyceride and phospholipid by chronic treatment with the drugs. The cross-sectional area of the intima, expressed as relative values to media (I/M ratio), was increased by the catheterization, showing intimal thickening in the denuded arteries. The I/M ratio was reduced by fluvastatin but not pravastatin: 0.327 +/- 0.060 for control, 0.116 +/- 0.035 for 4 mg/kg fluvastatin, 0.088 +/- 0.027 for 8 mg/kg fluvastatin and 0.22 +/- 0.069 for 8 mg/kg pravastatin. Fluvastatin (8 mg/kg)-induced effect on the I/M ratio, was prevented by the combined administration with 40 mg/kg per day mevalonate, a metabolite in the HMG-CoA reductase pathway. These results suggest that fluvastatin inhibits intimal thickening after catheterization-induced injury through percutaneous transluminal coronary angioplasty (PTCA) and that the inhibition is presumably attributed to reduced migration and proliferation of smooth muscle cells but not secondarily to a lowering of serum lipid.

Animals↗
PubMed1996

A study of the development of atherosclerosis in childhood and young adults: risk factors and the prevention of progression in Japan and the USA. The Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Research Group.

Coronary heart disease (CHD), one of the prevalent results of atherosclerotic disease, has been a leading cause of death in many Western countries for several decades, and now is the second most prevalent cause of death in Japan. Thus attention must also be paid to atherosclerosis in Japan. While there has been a remarkable reduction in the mortality rate from CHD in some Western countries, an undesirable stabilized mortality rate has recently been reported by the government of Japan. This report emphasises the importance of preventing atherosclerosis at an early stage from the viewpoint of cardiovascular pathology, using evidence from statistical data derived from autopsied cases in Japan and the USA.

Adolescent↗
PubMed1996

[Basic and clinical studies of pazufloxacin on infectious enteritis research group of T-3761 on infectious enteritis].

A clinical study was carried out on pazufloxacin (PZFX) in 137 patients including shigellosis, Salmonella enteritis, enteropathogenic Esherichia coli enteritis and cholera, and carriers of these pathogens. Antibacterial activity of PZFX against clinical isolates, fecal concentration of PZFX and effects of PZFX on fecal microflora were also investigated. The overall clinical efficacy rate was 97.2%. The bacteriological efficacy rates were 98.2% against Shigella spp., 81.8% against Salmonella spp., 50% against Vibrio cholerae O1, and 100% against E. coli, V. parahaemolyticus, Aeronomas spp., Plesionomas shigelloides and V. cholerae non-O1, respectively. Side effect (epigastralgia) was observed in 1 of 130 cases (0.8%). The rate of abnormal laboratory findings was 11.2% (11/98). These were mainly elevation of GOT and/or GPT and increased eosinophils. The clinical usefulness rate was 95.2%. The MIC90 values of PZFX against Shigella spp., Salmonella spp. and E. coli were 0.025, 0.025 and 0.025 micrograms/ml, respectively. The results of fecal drug concentration and the effects on fecal microflora in one patient were compatible with those obtained in healthy volunteers.

4-Quinolones↗
PubMed1996

[Atherosclerosis regression in the elderly--correlation between centrally depressed lesions and risk factors].

Atherosclerotic plaque with central depression (depressed lesion) may indicate regression of atherosclerosis in the aorta. Aortic depressed lesions have a solitary elevated area of plaque with a sharply-bordered roung depression in its center and no area ulceration. This may be interpretable as a sign of regression of atherosclerosis. To clarify the pathogenesis of depressed lesion, we studied clinical risk factors such as hypercholesterolemia in patients with depressed lesions that were confirmed at autopsy. The patients were divided into 3 groups according to their total cholesterol level at autopsy: a high-risk group (> or = 220 mg/dl), a moderate-risk group (180-220 mg/dl), and a low-risk group (< or = 180 mg/dl). Depressed lesions were found in 16.4% of those in the high-risk group, in 14.6% of those in the moderate-risk group and in 69.0% of those in the low-risk group. Severe aortic atherosclerosis was found in 69.8% of the patients; 50.9% of those with severe disease were in the-low risk group. Depressed lesions were also found in those with low levels of low-density lipoprotein cholesterol (< or = 140 mg/dl), 58.8% of whom were found to have severe atherosclerosis. There was no relationship between total cholesterol level and the presence of depressed lesions. However, a clinical prevention trial may result in sufficient control of ahterosclerosis among those in the high-risk group and may also lead to regression of aortic lesions.

Aortic Diseases↗
PubMed1995

A comparison of coronary arteries from Japanese and NZ subjects.

This paper describes a comparison of the anterior descending branch of the left coronary artery from 198 Japanese subjects of ages less than 60 yrs, with 301 New Zealand individuals of similar ages. The object of the study was to determine whether there were structural differences present which could be partially responsible for the low incidence of atherosclerosis in Japanese as well as the known low blood lipid levels. It was found that the internal elastic lamina of Japanese coronary arteries was less well formed at birth than that of NZ subjects. Intimal thickening was greater in Japanese coronary arteries from birth to the end of the first decade, but increased less rapidly with age, and was only about half as great as that of NZ vessels in the older age groups. The thickened intima of Japanese arteries was more uniform round the circumference of the vessel, the luminal surface was better formed with more stainable elastin present subjacent to the endothelial cells, and there was less evidence of mural thrombosis. NZ arteries showed pronounced eccentricity of the intima, more extensive lipid deposits, a poorly defined luminal surface, and frequent evidence of mural thrombosis.

Adolescent↗
PubMed1995

Walking exercise and improved neuropsychological functioning in elderly patients with cardiac disease.

OBJECTIVES: The present study examines the effects of exercise by walking on demented elderly patients with cardiac diseases. DESIGN: Walking exercise, mental activity and brain atrophy were assessed by using the number of steps. Hasegawa's dementia score and computed tomography, respectively. SETTING/SUBJECTS: Forty-six elderly patients with cardiac disease who were living in a metropolitan city. INTERVENTIONS: The Hasegawa dementia score was determined for each patient. The memory scores were used to divide the patients into four groups: normal, > 30.0; subnormal, 30.0 approximately 22.0; predementia, 21.5 approximately 10.5; and dementia, < 10.0. The walking exercises were performed every day. We also studied the ratio of the fullness of the brain (S1) to head size (S), represented as a percentage (S1/S x 100). We screened our patients for depression by means of a self-rating depression test. MAIN OUTCOME MEASURES: Walking exercise and improved mental activities. RESULTS: The mean numbers of the steps per day for the groups were 3386 +/- 676 (normal), 1008 +/- 193 (subnormal), 1597 +/- 661 (pre-dementia) and almost no walking (dementia). The mean values of the S1/S ratio for the first three groups were as follows: normal, 84.8 +/- 3.2; subnormal, 79.2 +/- 4.3; and predementia, 76.8 +/- 4.9. Only one patient was positive with regard to the depression test. CONCLUSIONS: The mental activity of elderly cardiac patients with dementia and/or brain atrophy improved with exercise from walking.

Aged↗
PubMed1995

[Quality assurance of pathology laboratories: analysis of histopathological diagnosis of endoscopical biopsies from lower alimentary tract based on specimen types].

As a part of the internal quality assurance in the pathology laboratories, we focused on the diagnosis of biopsies from the lower alimentary tract, and investigated the number of independent lesions contributing the specimens, biopsy pieces, and paraffin blocks prepared in each pathological examination, from the standpoint of the types of biopsy procedures employed. In addition, we compared those of pre- and post-operative diagnoses, and examined the adequacy in the cases with repeated biopsies. Regarding the procedures, polypectomy and EMR (endoscopical mucosal resection) accounted for more than 60% of all the specimens handled during the study period. Most of the specimens taken by polypectomy or EMR were derived from neoplastic conditions, and roughly 40% of them were from malignancies including borderline lesions in a narrow sense. The examination of the surgically resected specimens confirmed a hundred percent accuracy ratio of the diagnosis on the biopsy specimens. Three cases (7.1%) out of 42 malignancies resected needed repeated biopsies in preoperative confirmation of malignancy, while the remainder (92.9%) had been diagnosed at the initial biopsy. The result disclosed that biopsies possessing both diagnostic and therapeutic value (polypectomy and EMR) are apparently increased in the field of lower alimentary tract, and the difficulty and efforts required for diagnosis are quite different and depend on the biopsy procedures employed.

Biopsy↗
PubMed1995

[Immunohistochemical study of proliferation index of astrocytomas classified by new histopathological grading].

A new grading method of astrocytoma, proposed by Daumas-Duport et al, was based on four criteria:nuclear atypia, mitosis, necrosis and endothelial proliferation (0 criteria = Grade 1, 1 criteria = Grade 2, 2 criteria = Grade 3, 3 or 4 criteria = Grade 4). To elucidate the correlation of the classification based on four criteria, cellularity and proliferative activities, we studied proliferating index of 67 astrocytomas, using immunohistochemical staining for Ki-67 antibodies (MIB-1). A new grading method was related to proliferating index in this study, however, cellularity of tumor cells was not related to proliferating index. In this study, endothelial proliferation was invariably seen in high grade(Grade 3 and 4) astrocytomas. These tumor vessels were associated with dysfunction of blood-brain barrier and some growth factors accelerated to tumor cell proliferation. Relation between histopathological grade of astrocytoma and proliferation index was supposed, and new grading system was thought to be useful for routine pathological examination.

Adolescent↗
PubMed1994

Polyhedral assembly of a membrane protein in its three-dimensional crystal.

A novel ordered assemblage of bacteriorhodopsin, a transmembrane protein functioning as a light-driven proton pump, is found in its three-dimensional crystal. Atomic force microscope images of the crystal surface reveal that spherical protein clusters with a diameter of approximately 50 nm are hexagonally close-packed. Electron micrographs of mechanically disintegrated crystals show that the inside of the protein cluster is filled with the mother liquor. The crystal is made up of hollow protein clusters. When disintegrated crystals are illuminated in the presence of a lipophilic anion, a significant alkalization of the external medium occurs. This result indicates that the protein cluster contains native lipids and that the cytoplasmic side of the protein faces the external medium. X-ray diffraction patterns and the observed diameter of the spherical shell suggest that approximately 200 bacteriorhodopsin trimers are aligned on a polyhedral surface lattice. Another remarkable feature of the spherical assemblies of bacteriorhodopsin is that they fuse with each other at low ionic strength and occasionally form a tubular or doughnut-like structure. The concept of membrane protein polymorphism is introduced on the basis of these observations, and it is used to describe the dynamic structure of some other biological membranes.

Bacteriorhodopsins↗
PubMed1994

[A pathomorphological study of atherosclerotic plaque with central depression in the elderly].

A total of 161 atherosclerotic plaques from 50 aortas in elderly autopsy cases were pathomorphologically investigated to clarify the pathogenesis of atherosclerotic plaque with central depression. Atherosclerotic plaques with central depression, with well defined borders were employed for this study, ulcerated plaques being excluded. Pathomorphological findings showed that plaques with central depression could be divided into four groups according to their derivation respectively; (a) fused lesion of multiple fibrous plaque, (b) regressing lesion of plaque, (c) healing lesion of ulcerated atheromatous plaque, (d) mixed type. Finally, it was suggested that atherosclerotic regression may cause some central depression in the atheromatous plaques.

Aged↗
PubMed1994

[Elective course "Anatomic Pathology"].

The elective course "Anatomic Pathology" consists of three domains including (1) autopsy, (2) surgical pathology (biopsy) and (3) cytology. The major objectives are to gain knowledge and master various technics to make a high quality pathomorphological diagnosis. The training duration is fundamentally 2 years, but can be shortened to 1 year. The GIOs and SBOs of each domain are listed separately followed by specific learning subjects such as special stains, immunohistochemistry, electron microscopy, microbiology and forensic pathology. The major diseases in the various systems and organs are included. The minimal requirement for each domain is also mentioned.

Anatomy↗
PubMed1994

[An evaluation study on arbekacin for MRSA-infectious diseases including pneumonia, septicemia and others].

Availability of arbekacin (ABK) was analyzed in the chemotherapy of 24 MRSA-infected patients with symptoms of pneumonia (12), sepsis (6) and others (6). Most patients had background diseases such as malignant tumors or cerebrovascular disorders. 47% (7/15) of them were immunologically abnormal. 17 of them had been previously treated with cephems, imipenem, minocycline or fosfomycin. The ABK therapy was performed with doses ranging 50-400 mg a day, divided into 1-3 times (mostly 100 mg x 2), and for 5-24 days. (18 patients were treated between 5 and 14 days). 14 patients (58%) received combined therapy with other antibiotics (mostly with beta-lactams, 12). The clinical efficacy rate of the ABK therapy was 62% (good, 13; fair, 4; ineffective, 4; unknown, 3). The bacteriological efficacies were: eradicated, 7 (44%); decreased, 4; no change, 5; unknown, 8. Side effects were found in 3 patients (oliguria, 2; eruption due to drug, 1) and one case resulted in serious renal disorder. Abnormal laboratory data were found in 7 cases. Above results have indicated that ABK is a useful antibiotic in chemotherapy of MRSA-infections.

Adult↗
PubMed1993

Electron diffraction study on two-dimensional domain structure of L-DPPC monolayer.

A spatial variation in the two-dimensional crystal lattice orientation of L-DPPC monolayer on a hydrophobic substrate was observed by use of an electron microscope with diffraction and dark-field techniques. It is shown that the monolayer has a mosaic structure with domains, each of which consists of a region with a homogeneously oriented lattice of L-DPPC molecules. The domain structure of L-DPPC monolayer on a hydrophilic surface is also discussed.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed1993

[Immunohistopathological analysis of estrogen receptors in human meningioma].

We studied immunohistochemically estrogen receptors (ER) in 25 meningiomas removed from 20 patients using formalin-paraffin sections. Estrogen and progesterone receptors were studies in three case of meningiomas using frozen sections, also. Only two cases show positive reactions for estrogen receptor using formalin-paraffin sections. No correlation was found between estrogen receptor state and histological type, or biological behavior except for sex. Frozen sections failed to show the positive reaction for estrogen or progesterone receptors at all. The data suggest that estrogen receptors are detected in a few of the case with meningioma. Immunohistochemical analysis for estrogen receptor do not offer the useful informations in histopathological diagnosis or estimation of biological behaviors for meningioma on routine laboratory works.

Adult↗
PubMed1993

[Roles of pathology laboratories on medical care service and quality assessment system for pathological diagnosis].

In practical medicine, pathologists provide highly specialized medical information (pathological diagnosis) to clinicians. Pathological diagnosis includes histopathology, cytology, intraoperative consultation (rapid diagnosis by frozen section) and autopsy service. In particular, histopathological diagnosis of biopsy specimens, nearly always gives a qualitative diagnosis to unknown pathological process, in other words, a final diagnosis. In addition, pathological diagnosis contributes to supporting medical audit. Thus it is quite important that to establish the quality assessment system for pathological diagnosis which is hard to be judged with the value.

Autopsy↗
PubMed1992

Three-dimensional reorganization of a cell line of papilla Vateri adenocarcinoma in various culture conditions.

SAV-I, a cell line derived from a well differentiated adenocarcinoma of Vater's papilla, was cultured under four different conditions using collagen gel matrices (type I collagen): 1) double-layered, 2) floating double-layered, 3) embedded, and 4) floating embedded, then observed by light and electron microscopy and immunohistochemistry. Under all four conditions, three-dimensional growth with tubules occurred. In particular, the floating double-layered condition, where the cells were cultured between two collagen gel layers, then floated onto the medium, was useful for showing cellular reorganization. The three-dimensional growth patterns observed in vitro closely resembled the in vivo growth of SAV-I cells transplanted into nude mice. Therefore, we conclude that the floating double-layered condition is useful for demonstrating the morphological characteristics of the parent cells of established cell lines, and should be advantageous for studies of the relationship between cellular morphology and function in vitro.

Adenocarcinoma↗
PubMed1992

[Current alteration of Helicobacter pylori in gastro-duodenal diseases].

The current alteration of the detection rate of Helicobacter pylori (H. pylori) on mucous membranes of the stomach has been surveyed and reviewed for 49 cases of gastro-duodenal diseases. The survey has been conducted for 3 years and an endoscopic examinations have been performed 2-8 times. On the first visit, the diagnosis can be made endoscopically, and H2 blockers and another agents were used as therapeutic drugs. The detection rate was 67.3% (33 cases) for positive cases and positive reaction cases, while the rate was 32.6% (16 cases) in negative cases and negative reaction cases. Among them, the most commonly observed disease was atrophic gastritis, followed by duodenal ulcer, and acute gastric mucous lesions (AGML). Peptic ulcer was not seen. After administration of H2 blockers and anti-ulcer agents, the H. pylori-detection rate was found to fluctuate according to the diseases and alterations in the morbidity period. Some cases indicated the disappearance of H. pylori in accordance with the improvement of the lesion site.

Adult↗