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O Sasaki

Publications and source records attributed to O Sasaki.

At least 37 records · Page 2Linked to original sources
PubMed2000

The effects of intense click sounds on velocity storage in optokinetic after-nystagmus.

Vestibular evoked myogenic potentials (VEMP) occurring after click stimulation in cervical muscles are thought to be a polysynaptic response of otolith-vestibular nerve origin. In optokinetic after-nystagmus (OKAN) the direction of after-nystagmus changes and slow-phase velocity decreases with head tilt. This phenomenon may be an otolith response to the direction of gravity. We assumed that intense clicks might have some influence on OKAN via the otolith-vestibular nerve. Twelve normal subjects who showed VEMP at 75 dB normal hearing level (nHL) clicks were examined. The OKAN was recorded under four conditions: right monaural, left monaural and binaural stimulation by 75 dB nHL clicks, and absence of click stimulation. Horizontal optokinetic stimulation was applied using stepwise increasing speeds from 30 deg/s to 90 deg/s. Two seconds before the stimulus ended, clicks were sounded. The slow-phase velocity of the recorded electro-nystagmography was manually measured. There was no effect on OKAN with unilateral stimulation but binaural stimulation suppressed it. These results suggest that a velocity storage integrator is influenced by intense clicks via the otolithic area.

Acoustic Stimulation↗
PubMed2000

Coronary spastic angina induced by anticholinesterase medication for myasthenia gravis--a case report.

Myasthenia gravis (MG) is characterized by weakness of skeletal muscles because of a decrease in the number of available acetylcholine receptors at neuromuscular junctions. Anticholinesterase medication is widely used to treat MG, but muscarinic side effects sometimes appear and limit the drug usage. To their knowledge, the authors present the first case of coronary spastic angina quite possibly induced by anticholinesterase medication to treat MG. The appearance of coronary spastic angina in the present case is likely mediated through the increase of acethylcholine by anticholinesterase medication.

Aged↗
PubMed2000

Effects of coronary blood flow on left ventricular function in essential hypertensive patients.

To elucidate the mechanism of left ventricular dysfunction associated with left ventricular hypertrophy in hypertension, coronary blood flow (CBF) and left ventricular mass (LVM) were measured in 62 patients with essential hypertension (mean age, 54 +/- 13 years) and 22 normotensive control subjects (mean age, 57 +/- 13 years). According to the indicator fractionation principle, CBF/cardiac output (CO), estimated on the basis of the ratio of myocardial uptake/total injected dose of thallium-201 (% cardiac uptake), was measured. CBF and CBF per 100 g of myocardium (unit CBF) were calculated according to the following formulas: CBF=% cardiac uptake x CO, and unit CBF=(CBF/LVM) x 100, where CO and LVM are echocardiographically determined. Midwall fractional shortening (FS) and isovolumic relaxation time (IRT) were calculated as the indices of systolic and diastolic functions. CBF was greater in hypertensives than in controls (218.2 +/- 74.0 vs. 187.4 +/- 40.4 ml/min, p < 0.05), though unit CBF was smaller in hypertensives than in controls (99.1 +/- 22.0 vs. 141.2 +/- 31.6 ml/min/100 g, p < 0.0001). Multiple regression analyses showed that unit CBF was the most potent predictor of both midwall FS and IRT. A positive correlation was found between midwall FS and unit CBF (r=0.669, p < 0.0001), and a negative correlation between IRT and unit CBF (r=-0.579, p < 0.0001). In conclusion, myocardial ischemia reflected by the decrease in unit CBF may be closely related to left ventricular dysfunction in patients with essential hypertension.

Adult↗
PubMed1999

The simple indicator for revascularization of acute middle cerebral artery occlusion using angiogram and ultra-early embolectomy.

BACKGROUND: The purpose of the study was: (1) to find a clinical indicator for revascularization of acute middle cerebral artery (MCA) occlusion using angiograms of 100 patients examined immediately after onset and treated medically and (2) to investigate 10 ultra-early MCA embolectomies. METHODS: Quantity of collateral circulation, based on time required for conduction of contrast media to the insular portion of the MCA from the anterior cerebral artery, MCA conduction time (MCT) was graded as: Grade 1: In the arterial phase, there was conduction not only to the insular portion of the MCA but also to proximal M2; Grade 2: Conduction to the insular portion was present in late arterial phase; Grade 3: Conduction was present in capillary phase; Grade 4: Conduction was present in venous phase; Grade 5: No conduction was seen. The results of embolectomy are discussed. RESULTS: MCT can predict the extent of resultant low-density area on computed tomographic scan. For Grades 3, 4, or 5, embolectomy could be considered superior to medical treatment, if the low-density area was localized in the basal ganglia or centrum semiovale after surgery. Consequently, embolectomy was effective in four cases recanalized within 6 hours of onset. Except for one Grade 5 case, the remaining nine cases showed neither lethal hemorrhagic infarction nor brain edema. Overall outcome was significantly better than cases treated medically (p < 0.05), but some cases did not recover from hemiparesis due to infarcts in the area of the lenticulostriate arteries. CONCLUSIONS: MCT helps to predict the applicability of revascularization of acute MCA occlusion. Efficacy of embolectomy depends on revascularization within 6 hours of onset. Even after complete MCA flow restoration, infarcts in the area of the lenticulostriate arteries cannot always be prevented.

Acute Disease↗
PubMed1999

Clinical implications of circulating soluble Fas and Fas ligand in patients with acute myocardial infarction.

BACKGROUND: Apoptotic cell death is the major form of myocardial damage produced by coronary ischemic events. OBJECTIVE: To assess whether circulating levels of soluble Fas (sFas), an inhibitor of apoptosis, and sFas ligand, an inducer of apoptosis, in patients with coronary artery disease are greater than normal. METHODS: Forty-seven patients [acute myocardial infarction (AMI) in 17, old myocardial infarction (OMI) in 15, stable angina in 15] and 10 normal control subjects participated in this study. Serum levels of sFas and sFas ligand in all patients were measured, and cardiac catheterizations were performed. RESULTS: Serum levels of sFas were greater than normal only in patients with AMI (4.6 +/- 1.6 ng/ml); the levels were significantly higher than those in patients with OMI (2.1 +/- 0.6 ng/ml) and stable angina (2.2 +/- 0.5 ng/ml), and in normal subjects (2.0 +/- 0.6 ng/ml; P < 0.0001). However, there was no difference among serum levels of sFas ligand for all groups. For patients with AMI, there was no significant correlation between serum levels of sFas and peak levels both of plasma creatine phosphokinase and of plasma myosin light chain type I as clinical indexes of infarct size. However, there were significant correlations between serum levels of sFas and both pulmonary artery wedge pressure (r = 0.767, P = 0.0003) and left ventricular end-diastolic pressure (r = 0.629, P = 0.03). CONCLUSIONS: Circulating sFas increases in concentration in relation to the severity of hemodynamic conditions in patients with AMI, but it is independent from size of infarct. Therefore, circulating sFas could play an important role as the marker of pathophysiologic conditions associated with cardiomyocyte apoptosis in AMI.

Aged↗
PubMed1999

Serum creatinine level underestimates hypertensive renal involvement in elderly patients with essential hypertension.

It is well recognized that serum creatinine level provides a quick general assessment of renal function. However, we frequently encounter elderly hypertensive patients with renal involvement whose serum creatinine levels are within normal limits. The aim of this study was thus to determine whether serum creatinine level is a sensitive indicator of renal function in elderly hypertensive patients. Study groups were classified according to age: 82 elderly patients (aged 65 yr or older) and 98 middle-aged patients (aged 40-65 yr) with essential hypertension. To assess hypertensive renal involvement, serum creatinine and serum uric acid levels were measured. We also measured the left ventricular mass (LVM) index by using echocardiography as a marker of hypertensive target organ damage. There was no age-related difference in the LVM index, but the serum creatinine level in elderly hypertensive patients was significantly lower than that in middle-aged hypertensive patients. There was no significant difference in serum uric acid level between the two groups. In addition, the LVM index was correlated with the serum uric acid level (r = 0.46, p = 0.0001) but not with the serum creatinine level in elderly hypertensive patients. In middle-aged hypertensive patients, the LVM index was related to both serum uric acid level (r = 0.41, p = 0.007) and serum creatinine level (r = 0.43, p = 0.003). In conclusion, serum creatinine level may underestimate hypertensive renal involvement in elderly hypertensive patients. In contrast, serum uric acid level may be a sensitive indicator of hypertensive target organ damage irrespective of age.

Adult↗
PubMed1999

Detection of porcine epidemic diarrhea virus using polymerase chain reaction and comparison of the nucleocapsid protein genes among strains of the virus.

Two pairs of PCR primers were designed to perform nested PCR targetting of a 540 bp fragment of the nucleocapsid (N) protein gene (N gene) of porcine epidemic diarrhea virus (PEDV). The N gene of PEDV was amplified with 4 PEDV strains and 11 small intestines of PEDV-infected piglets collected from 2 farms in Kagoshima prefecture, Japan. Nucleotide sequences of the PCR products from a Korean and two Japanese strains (KKN96-1 and S1) of PEDV isolated in 1993 and 1996, respectively, were almost identical. These results suggest that the PCR is an available tool for detection of PEDV from pigs in the field, and that the two Japanese strains (KKN96-1 and S1) were genetically similar to the Korean strain.

Animals↗
PubMed1999

DNA ploidy, Ki-67 and p53 as indicators of lymph node metastasis in early gastric carcinoma.

OBJECTIVE: To perform flow cytometric and immunohistochemical analysis of early gastric carcinoma in order to investigate the clinical value of DNA ploidy, Ki-67 and p53 as indicators of lymph node metastasis. STUDY DESIGN: We studied 108 cases of surgically resected early gastric carcinoma, which comprised 21 cases showing positive lymph node metastasis (group A) and 87 cases showing negative lymph node metastasis (group B). RESULTS: Aneuploidy was seen in 16 cases (76.2%) in group A in contrast to 10 cases (11.5%) in group B (P = .0029). The mean value of the Ki-67 labeling rate in all cases was 21.9%, and 15 cases (79.0%) showed a Ki-67 labeling rate of more than 21.9% in group A, while they numbered 31 (37.4%) in group B (P = .0016). Cases with cell positive for p53 protein numbered 15 (75%) in group A, while they numbered 38 (46%) in group B (P = .0460). CONCLUSION: DNA aneuploidy, a high labeling rate of Ki-67 and overexpression of p53 are all useful indicators of lymph node metastasis in patients with early gastric carcinoma.

Aneuploidy↗
PubMed1999

Comparison of the intratumor DNA ploidy distribution pattern between differentiated and undifferentiated gastric carcinoma.

OBJECTIVE: To compare the differences in intratumor DNA ploidy distribution pattern between differentiated and undifferentiated carcinoma of the stomach. STUDY DESIGN: Two hundred five cases of surgically resected gastric carcinoma were studied, comprising 125 differentiated and 80 undifferentiated carcinomas. DNA ploidy was determined by means of flow cytometry in stepwise sections of the entire tumor. The intratumor DNA ploidy distribution pattern was compared between these two histologic types. RESULTS: Differentiated carcinomas comprised 35 cases of predominantly diploid (28%) and 90 cases of predominantly aneuploid (72%) tumors, while undifferentiated carcinomas comprised 46 cases of predominantly diploid (57.5%) and 34 cases of predominantly aneuploid (42.5%) (P < .01). The frequency of cases showing predominantly aneuploidy among the differentiated carcinomas was significantly higher than among the undifferentiated carcinomas at stages IA and IIIA. The rate of cases showing heterogeneity was lower among the early-stage cases than among the advanced-stage cases in both histologic types. Among the differentiated carcinomas, there were 22 cases that had more than six DNA stemlines in each tumor, whereas among undifferentiated carcinomas, there were six such cases (P < .05). CONCLUSION: There were more cases with high malignant potential among the differentiated carcinoma cases than among the undifferentiated carcinoma cases in the present series.

Adenocarcinoma↗
PubMed1998

Expression of endothelial and inducible nitric oxide synthase in human glomerulonephritis.

The presence of nitric oxide (NO) in the kidney has been implicated in the pathogenesis of human glomerulonephritis. However, the exact type of glomerular cells that express NO synthase (NOS) and the NOS isoform involved in the local production of NO has not been identified in the human diseased kidney. We examined the expression of three isoforms of NOS, inducible NOS (iNOS), endothelial NOS (eNOS) and brain NOS (bNOS) in the renal tissue of patients with IgA nephropathy (IgAN, N = 10), lupus nephritis (LN, N = 5), membranous nephropathy (MN, N = 5) and minimal change nephrotic syndrome (MCNS, N = 5). Sections were immunostained and the correlation between the expression of each NOS and the degree of glomerular injury in that section was also examined. Normal portions of surgically resected kidneys served as controls. eNOS was present in glomerular endothelial cells and endothelium of cortical vessels in the control and diseased kidneys. iNOS was localized in mesangial cells, glomerular epithelial cells and infiltrating cells in the diseased glomeruli, whereas immunostaining for iNOS was hardly detected in control kidneys. In addition, the expression pattern of eNOS in each glomerulus was the reverse of that of iNOS. In IgAN and LN, the extent of staining for eNOS correlated negatively with the degree of glomerular injury, while the extent of staining for iNOS correlated positively with the degree of glomerular injury in the same tissues. bNOS was not detected in normal or nephritic glomeruli. Our results indicate the presence of a NO pathway in human diseased kidney, and suggest that NO derived from eNOS and iNOS may be involved in the progression of renal diseases and that NO derived from each NOS may play an important role in different way in human inflamed glomeruli.

Adult↗
PubMed1998

A cutaneous agranular CD2- CD4+ CD56+ "lymphoma": report of two cases and review of the literature.

We report 2 cases of agranular CD2- CD4+ CD56+ non-Hodgkin lymphoma in which skin seemed to be the primary site. A 21-year-old woman's initial symptom was a skin nodule on the right cheek. She also had tumors in the nasopharynx, and the bone marrow subsequently became involved. No lymphadenopathy was present. She experienced complete remission after dose-intensified therapy with cyclophosphamide, hydroxydaunomycin, vincristine [Oncovin], and prednisone (CHOP), but the disease relapsed in the central nervous system 6 months later. An 81-year-old man experienced an 11-month history of skin nodules in the left forearm. On admission, he had a bone marrow infiltration of lymphoma cells. He died of pneumonia during chemotherapy. The malignant cells of the 2 patients had similar morphologic features, with a monocytoid nucleus and no cytoplasmic granules. The cells in both cases showed a unique phenotype: CD2-, CD3-, CD4+, CD8-, CD13-, CD14-, CD34-, CD16-, CD56+, CD57-, HLA-DR-positive. Staining for peroxidase and alpha-naphthyl butyrate esterase was negative. The T-cell receptor beta, gamma, delta, IgH, kappa, lambda genes were of germ line configurations. The DNA of Epstein-Barr virus was not detected from the bone marrow cells by polymerase chain reaction. Only 3 other cases with similar phenotypes have been reported; all had skin lesions. Although the origin of these cells remains unknown, we propose that this is a distinct clinicopathologic entity.

Adult↗
PubMed1998

Familial Crohn's disease with systemic lupus erythematosus.

We describe a young Japanese woman who was diagnosed with Crohn's disease affecting the ileum, transverse colon, and rectum, as confirmed by barium studies, colonoscopy, and histopathological examination. Her father and sister also had Crohn's disease. After a 4-yr course of sulfasalazine and elemental diet therapy, she was readmitted for perianal abscess associated with the presence of pancytopenia, microhematuria with granular cast, hypocomplementemia, and high titers of autoimmune antibodies (anti-ANA and anti-dsDNA antibodies). Based on these features, a diagnosis of systemic lupus erythematosus (SLE) was made. Despite the rarity of such combination (Crohn's disease with SLE), patients with Crohn's disease who develop such clinical findings might need evaluation for SLE.

Adult↗
PubMed1998

Therapeutic apheresis for renal diseases.

Plasma exchange is used frequently in renal diseases for the removal of the humoral components of immune responses. Various pathological circulating factors are recognized in primary and secondary renal diseases. Recent advances in medical technology have allowed a wider clinical application of plasmapheresis in the clinical management of a variety of conditions. However, the clinical efficacy of plasmapheresis in renal diseases is still controversial. In this article, we review the therapeutic use of apheresis in different renal diseases.

Anti-Glomerular Basement Membrane Disease↗
PubMed1998

Multivariate analysis of predictors of hematoma enlargement in spontaneous intracerebral hemorrhage.

BACKGROUND AND PURPOSE: We conducted this study to determine, through use of multivariate analyses, the independent predictors of hematoma enlargement occurring after hospital admission in patients with spontaneous intracerebral hemorrhage (i.c.h.). METHODS: We reviewed 627 patients with ICH admitted within 24 hours of onset. The first CT was performed at admission and the second within 24 hours of admission, and a blood sample was taken for laboratory examinations. Univariate and multivariate analyses were performed to assess the relationships between hematoma enlargement and time from onset, consciousness level, CT findings, amount of alcohol consumption, systolic blood pressure at and after admission, clinical outcome, and hematologic parameters. RESULTS: Eighty-eight patients (14.0%) showed enlarged hematomas after admission. Multivariate analyses revealed that the following five factors were independently associated with hematoma enlargement: the time from onset (odds ratio [OR], 0.26 for a 1-SD change; 4.9 hours; P < 0.001); the amount of alcohol consumption (OR, 1.50 for 1 SD; 46.3 g/d; P = 0.002); the sharp of hematoma (OR, 1.40 for 1 SD; 0.45 round; P = 0.006); the presence of consciousness disturbance (OR, 1.38 for 1 SD; 0.50 coma; P = 0.026); and the level of fibrinogen (OR, 0.74 for 1 SD; 87.1 mg/dL; P = 0.042). Hematoma enlargement was an independent factor increasing the mortality rate in the ICH patients (OR, 1.57; P < 0.001). CONCLUSIONS: A particularly high likelihood of hematoma enlargement was observed in patients who (in order of importance) were admitted shortly after onset, who were heavy drinkers; who had an irregularly shaped hematoma, whose consciousness was disturbed, and who had a low level of fibrinogen.

Aged↗
PubMed1998

The protective effect of Clostridium novyi type B alpha-toxoid against challenge with spores in guinea pigs.

Clostridium novyi (C. novyi) Type B alpha-toxin was purified from culture supernatant by column chromatography, and was inactivated by formalin. A purified alpha-toxoid vaccine was prepared by mixing it with an aluminum phosphate gel adjuvant. Guinea pigs immunized twice with 4 micrograms or more of alpha-toxin survived against challenge with C. novyi Type B spores. Anti-alpha-toxin (antitoxin) titer was measured by toxin neutralization test using Vero cells. All of the guinea pigs having antitoxin titers of 10 units (U) or more at challenge were survived. In another experiment, guinea pigs were immunized with crude alpha-toxoid vaccines prepared by inactivated culture supernatant or by adding broken bacterial cells to the former. In this experiment, 10 U of antitoxin titer was the border of survival or death after challenge. Guinea pigs with antitoxin titers of less than 5 U, 5 U and 10 U died at 2, 3 to 4 and 4 days, respectively, after challenge. These results suggest that C. novyi alpha-toxin was the main protective antigen against challenge exposure to spores in guinea pigs.

Animals↗
PubMed1998

Protective effect of NaOH-extracted Erysipelothrix rhusiopathiae vaccine in pigs.

A vaccine was prepared from a NaOH-extracted antigen of the Kyoto strain (serovar 2) of Erysipelothrix rhusiopathiae (E. rhusiopathiae) with an oil adjuvant, and was injected twice at 3-week intervals into SPF pigs and conventional pigs with maternal antibodies. After the second vaccination, IgG-GA titers of immunized SPF pigs were more than 256-fold at 3 weeks, and immunized pigs with maternal antibodies were 64-fold at 7 weeks. The pig with maternal antibodies vaccinated once with live vaccine had less than 4-fold titers. The ELISA antibody titers which were measured by using the NaOH-extracted antigen showed similar transition to the IgG-GA antibody titers. All immunized pigs and nonvaccinated control pigs were challenged with the strains Fujisawa (serovar 1a) or Saitama-1 (serovar 2). After challenge exposure, all pigs immunized with the NaOH-extracted vaccine showed no clinical signs and survived, and the pig immunized with the live vaccine had a local rhomboidal lesion at the site of the injection. Nonvaccinated pigs developed typical symptoms of E. rhusiopathiae infection and one of them died. After the autopsy, the challenge strains were not recovered from the main organs except tonsils of the pigs immunized with the NaOH-extracted vaccine. These results indicated that the NaOH-extracted vaccine induces a protective effect in pigs with maternal antibodies as well as in SPF pigs negative for such antibodies, and that 67-64, 62-60 kDa proteins in the NaOH-extracted antigen play an important role in protecting against E. rhusiopathiae infection.

Animals↗
PubMed1998

Reassessment of non-hodgkins's lymphoma with a "nodular" growth variant: a clinicopathologic study of follicular, mantle cell and marginal zone lymphomas prospectively diagnosed with multiparameter analyses.

Although three subtypes of non-Hodgkin's lymphoma (NHL), follicular lymphoma (FL), mantle cell lymphoma (MCL) and marginal zone lymphoma (MZL), are now well recognized as independent categories, their biological behavior has not been fully compared. One of the reasons for this may be that subclassification by histological examination alone is often difficult since they all have a common variant of a "nodular" growth pattern and occasionally show similar cytological morphology. Recently, we reviewed patients with FL, MCL and MZL, who were prospectively diagnosed, using multiparameter analyses with unfixed fresh biopsy materials. Of 407 NHL patients, 101 (24.8%) belonged to these three categories and 80 could be followed; FL (n=27), MCL (n=27) and MZL (n=26). Twenty eight cases with diffuse large B-cell (DL-B) lineage lymphoma were selected as control at random. The frequency of the MCL patients with performance status (PS) 2 to 4 (41%) was significantly higher than MZL patients (4%) [P< 0.001]. The 3 year survival rate with FL, MCL, MZL and DL-B was 71.5%, 57.4%, 93.3% and 53.1%, respectively. The survival rate for MZL was significantly better than both FL (p = 0.048) and MCL (p = 0.0085). Significant differences were also found in the overall survival rates among the four risk groups as defined by the International Index [I2](low, low-intermediate, high-intermediate and high; 97.4%, 79.6%, 39.4% and 18.2%, respectively). A multivariate analysis revealed that the International Index may be a significant predictor for short survival (p=0.0001) in the patients with FL, MCL or MZL. These results suggest that MZL shows an apparently better prognosis than FL and MCL and is found to be a prognostically independent category. In contrast, the clinical outcome in MCL is the worst among the three subtypes and was closer to that of DL-B. The International Index can be applied to a wide spectrum of NHL, including MCL, MZL and FL, to and can predict prognosis in these cases.

Adolescent↗