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Y Yasumoto

Publications and source records attributed to Y Yasumoto.

At least 19 recordsLinked to original sources
PubMed2002

Phagocytic and candidacidal activities of macrophages from suckling and adult mice pretreated with concanavalin-A.

In this study, we investigated the effect of concanavalin-A (Con-A) on the activation of phagocytosis and killing of Candida albicans by peritoneal macrophages from suckling and adult mice. Pretreatment of adult mice with Con-A dose-dependently increased the percentage of macrophages phagocytosing C. albicans in vitro from 3.8 +/- 0.9 to 24.2 +/- 2.4 in the absence of serum opsonins. Addition of mannan (50 microg) and mannose (50 mM) to the incubation medium reduced phagocytosis from 21.5 +/- 1.3 to 4.7 +/- 1.9, suggesting that treatment with Con-A increased phagocytosis mediated by mannose receptors. Killing of C. albicans was also increased by increasing the dose of Con-A. Pretreatment of suckling mice with Con-A increased the macrophages' phagocytic and candidacidal activities by an amount similar to that observed in adult mice. Furthermore, suckling mice pretreated with Con-A survived an intraperitoneal inoculum of 5 x 10(7) C. albicans, whereas all control mice died within 24-48 h of infection. This suggested that increased phagocytosis and killing of C. albicans stimulated by the action of Con-A conferred early protection upon suckling mice experimentally infected with C. albicans.

Animals↗
PubMed2001

Serum cystatin C may predict the prognostic stages of patients with IgA nephropathy prior to renal biopsy.

The relationship between the levels of serum cystatin C and the prognostic stages of IgA nephropathy was determined in a multicenter trial in Japan. The levels of serum cystatin C in patients with IgA nephropathy were measured using the Dade Behring N Latex Cystain C assay. In 1995, the Joint Committee of the Special Study Group on Progressive Glomerular Diseases, Ministry of Health and Welfare of Japan, and the Japanese Society of Nephropathy reported four prognostic stages. These are: good prognosis group (Group I), relatively good prognosis group (Group II), relatively poor prognosis group (Group III), and poor prognosis group (Group IV), for this disease. Three-hundred and six patients with IgA nephropathy and other glomerular diseases were examined. There were no significant changes in the levels of serum creatinine (Cr) or creatinine clearance (CCr) between Group I and Group II. The mean levels of serum cystatin C in Group II were significantly higher than those in Group I (P < 0.05). The mean levels of serum cystatin C in Group III or IV were significantly higher than those in Group I (P < 0.001, P < 0.005, respectively). These suggest that the measurement of serum cystatin C may predict the prognostic stages of patients with IgA nephropathy prior to renal biopsy.

Adult↗
PubMed2001

Vitamin E inhibits proliferation of primary cultured human mesangial and endothelial cells.

BACKGROUND: Vitamin E (VE) has been used as an antioxidant and has been suggested to inhibit the proliferation of mesangial cells in rat and vascular endothelial cells. The direct effect of VE on primary cultures of mesangial cells (MC) and endothelial cells (EC) from the human glomerulus was studied. METHODS: (1) MC (in 17 or 2.5% FCS DMEM) or EC (in 10 or 5% FCS CSC) at 5,000 cells/well was incubated with serial concentrations of VE from 0.05 to 50 microg/ml (0.06 to 60 IU/l). (2) MC was cocultured with 160, 80, 40 or 20 microg/ml of low-density lipoprotein (LDL) or oxidized LDL (ox-LDL) in 17 or 2.5% FCS DMEM with or without VE. After 3 days of incubation at 37 degrees C in 5% CO(2), cell proliferation was measured by the Premix WST-1 Assay System. RESULTS: The concentration of VE that significantly inhibited the proliferation of MC cultured in 17 or 2.5% FCS DMEM was 50 or 2.5 microg/ml (60 or 3.0 IU/l), respectively, and that of EC in 10 or 5% FCS medium was 50 or 25 microg/ml (60 or 30 IU/l). VE at 25 microg/ml (30 IU/l) inhibited the LDL proliferative effect on MC cultured in 2.5 FCS DMEM by 21.79-93.21% in a LDL concentration-dependent manner. There was little difference between the effects of LDL and ox-LDL on the VE inhibitory effect on MC under our experimental conditions. CONCLUSION: VE at low concentrations had no effect on the proliferation of both MC and EC, but at high concentrations, it showed an inhibitory effect on both cells.

Cell Division↗
PubMed2001

Primary pineal melanocytic tumor. Case report.

A primary melanocytic lesion arising from the pineal gland is very rare. The authors report a case of primary pineal melanocytic tumor with dissemination to the right hippocampus in a 50-year-old woman who presented with memory disturbance. Magnetic resonance (MR) imaging revealed a mass that was hyperintense on T1-weighted and hypointense on T2-weighted MR images. The pineal tumor was removed subtotally via the occipital transtentorial approach, and the patient underwent whole-brain irradiation. Results of histological examination revealed that the tumor predominantly consisted of atypical cells with scanty melanin pigment and some necrotic foci. The strongly pigmented areas of the tumor contained well-differentiated cells similar to those of melanocytoma. An ultrastructural study demonstrated evidence of a mature type of melanosome. The patient died 11 months after surgery and radiotherapy (1.7 years after the onset of symptoms). The autopsy findings demonstrated tumor invasion into the parenchyma through the leptomeningeal space and the ventricular wall. The tumor was diagnosed as being malignant, and it was finally concluded that the atypical cells in the tumor were probably responsible. This pineal melanocytic tumor exhibited a wide spectrum of differentiation, ranging from highly malignant melanoma to well-differentiated melanocytoma, which may have contributed to the patient's relatively long survival period. The biological behavior and morphological characteristics of this tumor appear to be similar to those of other pineal parenchymal lesions.

Fatal Outcome↗
PubMed2000

Evaluation of regional cerebral blood flow in chronic subdural hematoma.

To clarify the mechanism responsible for neurological impairment associated with chronic subdural hematoma (CSDH), we performed quantitative measurements of cerebral blood flow (CBF) with xenon-enhanced computed tomographic scans in eight patients with unilateral CSDH. Vascular reserve capacity was also evaluated with acetazolamide challenge. CBF was depressed in all regions examined except the corona radiata. There was no statistical difference in hemispheric and regional CBF between the lesion and non-lesion sides. A significant increase in CBF values ranging from 32% to 69% was observed after acetazolamide administration in the whole brain. Postoperatively CBF remained depressed in all regions we analyzed except for the frontal and temporal lobes, despite the fact that all patients had improved clinical symptoms. Amplitude of N20 and central conduction time (N13-20) in SSEP showed no significant change in CSDH patients compared to normal control. So we conclude that preoperative neurological signs in CSDH are related to a reduction of CBF in the whole brain. However, other mechanisms must be involved to explain preoperative focal signs and good postoperative recovery.

Adult↗
PubMed2000

[A case of multiple metastatic brain tumors with repeated intracerebral hemorrhages].

We report a case of multiple metastatic brain tumors with repeated intracerebral hemorrhages. A 73-year-old man suffered from a cerebellar hemorrhage. Subsequent hemorrhages repeatedly occurred in the right temporal lobe, the 4th ventricle, the midbrain, and the septum pellucidum. Three months after admission, CT revealed enhanced masses with surrounding edema in the cerebellar vermis and midbrain, suggesting brain tumors. We eventually diagnosed these masses in an autopsy as metastatic brain tumors of lung adenocarcinoma. Intravascular embolization with tumor cells was a probable cause of the multiple repeated intracerebral hemorrhages.

Adenocarcinoma↗
PubMed2000

Measurement of serum IgA and C3 may predict the diagnosis of patients with IgA nephropathy prior to renal biopsy.

The levels of serum IgA and C3 in patients with IgA nephropathy were determined using international standard serum (IFCC/CRM470) in a multicenter trial in Japan. The ratio of serum IgA to C3 (serum IgA/C3 ratio) without any information from renal biopsy was used for the diagnosis of IgA nephropathy. Three hundred and six patients with IgA nephropathy and other glomerular diseases, and 418 healthy adults were examined. The new diagnostic standardized criterion in patients with IgA nephropathy, obtained by nephelometric immune assay based on the international reference preparation CRM470, was 315 mg/dl. The serum IgA/C3 ratio was a more useful marker for distinguishing IgA nephropathy from non-IgA nephropathy together with serum IgA levels. This suggests that the measurement of serum IgA and C3 may predict the diagnosis of patients with IgA nephropathy prior to renal biopsy.

Adult↗
PubMed1997

Case of propylthiouracil-induced vasculitis associated with anti-neutrophil cytoplasmic antibody (ANCA); review of literature.

A 39-year-old Japanese woman had been receiving propylthiouracil for 5 years for hyperthyroidism when she developed myalgia, scleritis, proteinuria, fever, and inflammation of the nose. Examination of a renal biopsy specimen showed focal segmental necrotizing glomerulonephritis. Indirect immunofluorescent staining showed a highly positive perinuclear pattern of anti-neutrophil cytoplasmic antibody (ANCA) in her serum. Enzyme-linked immunosorbent assay (ELISA) of the ANCA showed positivity for anti-proteinase 3, anti-myeloperoxidase, anti-leukocyte elastase, and anti-lactoferrin, but anti-cathepsin G and anti-lysozyme were negative. Because ELISA showed the titer of anti-leukocyte elastase antibody to be markedly elevated, we challenged this data by performing dot blot analysis. The patient's serum reacted with the native form, but not with denatured leukocyte elastase. Propylthiouracil-induced vasculitis was suspected. Symptoms abated within 2 weeks and all values of ANCA were reduced after the drug was withdrawn. Vasculitis is a rare side-effect of propylthiouracil therapy. Recently it was reported in association with ANCA. We present the findings of this patient and compare them with those described in 19 published cases of propylthiouracil-induced vasculitis associated with ANCA.

Adult↗
PubMed1996

Characterization of a rat liver Golgi sulphotransferase responsible for the 6-O-sulphation of N-acetylglucosamine residues in beta-linkage to mannose: role in assembly of sialyl-galactosyl-N-acetylglucosamine 6-sulphate sequence of N-linked oligosaccharides.

Rat liver Golgi membranes were found to contain an enzyme that can transfer sulphate from 3'-phosphoadenosine 5'-phosphosulphate (PAPS) to C-6 of the terminal GlcNAc in beta-linkage to mannose and has properties indicating that it is involved in the synthesis of the NeuAc alpha 2-3(6)Gal beta 1-4GlcNAc(6-SO4) sequences observed in the N-linked carbohydrate units of various glycoproteins. Assays performed with [35S]PAPS (Km 0.67 microM) and GlcNAc beta 1-6Man alpha 1-O-Me (GnMaMe) acceptor (Km 0.71 mM) indicated that the sulphotransferase had a pH optimum of approx. 7.0 and is markedly stimulated by Mn2+ ions (maximum approx. 15 mM) and Triton X-100 (0.05-0.1%). Hydrazine/nitrous acid/NaBH4 treatment of the 35S-labelled product yielded radiolabelled 2,5-anhydromannitol(6-SO4). The sulphated GnMaMc product of the GlcNAc-6-O-sulphotransferase could be galactosylated by a rat liver Golgi enzyme that was shown to have the same properties as the UDP-Gal:GlcNAc beta-1,4-galactosyltransferase from bovine milk. Competition studies performed with GlcNAc and GlcNAc-6-SO4 furthermore indicated that the same liver enzyme acted on both acceptors to produce Gal beta 1-4GlcNAc and Gal beta 1-4GlcNAc(6-SO4) with Km values of 1.04 and 1.68 mM respectively. Because the sulphated N-acetyl-lactosaminc could in turn serve as an acceptor for rat liver sialyltransferase, it seems that this enzyme, together with the Golgi galactosyltransferase and the GlcNAc-6-O-sulphotransferase, could act in concert in assembling the NeuAc alpha 2-3(6)Gal beta 1-4GlcNAc(6-SO4) branches of complex N-linked oligosaccharides.

Acetylglucosamine↗
PubMed1994

[Protective effects of KC-764 on short-term forebrain ischemia in gerbils].

KC-764, developed as a cyclo-oxygenase inhibitor, was administered to gerbils in a dose of 10 mg/kg, i.p., before subjecting them to 5-minute bilateral forebrain ischemia in order to determine whether it would have any protective effects. No post-ischemic hyperthermia (over 39 degrees C for 120 min) was observed in the KC-764 group. Behavior recovery time after ischemia was 11.4 +/- 2.8 minutes in the KC-764 group versus 87.3 +/- 13.4 minutes in the control group (p < 0.05). Delayed neuronal death (DND) in the CA1 region of the hippocampus was inhibited in the KC-764 group, but when the KC-764-treated animals were exposed to hyperthermia, the degree of DND was the same as in the control group. EEG voltage recovery time in the CA1 region of the hippocampus was almost the same in the control group, the KC-764 group, and the KC-764-plus-hyperthermia (HT) group. Although tissue blood flow measurements in the CA1 region of the hippocampus showed post-ischemic hypoperfusion (81 +/- 18% of the pre-ischemic level at 60 minutes), it was prevented in the KC-764 group (102 +/- 21%) (p < 0.05) and the KC-764-plus-HT group (96 +/- 28%). There was a tremendous increase in PGD2 (1461.4 +/- 863.4 p mol/g) and PGF2 alpha (219.6 +/- 104.2 p mol/g) in the forebrain after 5 minutes of reflow, but this increase in prostaglandin levels was inhibited (p < 0.05) in the KC-764 group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

[A clinicopathological study of 21 cases of primary central nervous system lymphoma].

A clinico-pathological study was carried out in 21 cases of primary central nervous system-non-Hodgkin's lymphoma (CNS-NHL). Their clinical profiles (age, prognosis, modalities of treatment) and findings of radio-imaging were analyzed. All specimens from surgery and/or autopsy were histologically classified according to the working formulation (WF) classification of the National Cancer Institute. Ontogeny of lymphoma cells was determined by immunohistochemical study in all cases and some cases were subjected to light (kappa, lambda) and heavy chain (IgG, IgA, IgM) analysis as well. Among 21 cases, 12 cases were located in the cerebral hemisphere, 7 in the thalamus-basal ganglia and 4 in the cerebellum. Radio-imaging study showed that 18 cases (86%) revealed isodensity mass lesions on plain CT, which were homogeneously enhanced by contrast medium. The pathological study showed that all cases were derived from B-cells. Five were classified as immunoblastic type (IBL), 9 as diffuse large type (DL), and the others were classified according to WF. 17 of 21 cases (81%) were sensitive to radiotherapy, and 15 of 19 cases (79%) responded to corticosteroid. A prognostic study revealed that patients with IBL had less hope than those with DL. From this result, it seems that WF classification is better than LSG classification for obtaining a prognosis in malignant lymphoma patients. The frequency of primary CNS-NHL has been increasing for the past several decades and will surpass that of any other brain tumors in the near future because of the explosive expansion of AIDS patients. Therefore, not only clinicopathological analysis but also biological study for CNS-NHL might be important.

Adult↗
PubMed1993

[Cefuzonam penetration into cerebrospinal fluid].

We studied the penetration of cefuzonam (CZON) into the cerebrospinal fluid (CSF) in 20 patients with neurosurgical diseases. Influences of the presence of meningeal reaction and the intensity of brain damage on CSF penetration of CZON were also examined. Concentrations of CZON in serum and CSF were determined using the thin-layer cup method before and 1, 2, 4, and 6 hours after 2 g of CZON was administered intravenously. The serum concentration at 1 hour was 60.4 +/- 31.3 (mean +/- S.D.) microgram/ml, then rapidly decreased to 2.1 +/- 2.3 micrograms/ml at 6 hours. In contrast, the CSF concentration gradually increased, reached a peak level of 0.319 +/- 0.313 micrograms/ml at 4 hours and then slowly decreased to 0.273 +/- 0.249 micrograms/ml at 6 hours. The CSF penetration ration: CZON ([CSF]/[serum]) was 5.6% at 4 hours. The peak CSF concentration in patients with meningeal reaction (0.465 +/- 0.364 micrograms/ml at 2 hours) was about 2-fold higher than that in those without the reaction (0.249 +/- 0.223 micrograms/ml at 4 hours). The peak CSF concentrations in patients with slight, moderate, and severe brain damage were 0.231 +/- 0.133 micrograms/ml at 4 hours, 0.270 +/- 0.232 micrograms/ml at 4 hours, and 0.680 +/- 0.467 micrograms/ml at 2 hours, respectively. CSF penetration of CZON was augmented in patients with meningeal reaction or severe brain damage. These findings indicate that the concentration of CZON in CSF after intravenous administration is sufficient for treatment of meningitis or infections after neurosurgical operations caused by such bacteria as Escherichia coli, Klebsiella pneumoniae, Haemophilus influenzae, and Streptococcus pneumoniae.

Adult↗
PubMed1992

[Effects of steroid therapy in IgA nephropathy].

In order to estimate the effects of corticosteroid therapy in IgA nephropathy cases with daily urinary protein excretion of 1.0 g/day or more. 26 patients (8 men and 18 women, aged 32.6 +/- 14.0 years old) were subjected to this study. The results obtained were as follows: Urinary protein excretion after 1 year from the beginning of steroid therapy (1.56 +/- 1.14 g/day) was significantly (p less than 0.05) lower than that at the beginning of the therapy (4.61 +/- 6.01 g/day). In serum creatinine levels, there was no statistically significant difference with them between at the beginning (1.15 +/- 0.48 mg/dl) of steroid therapy and at the time of 1 year after (1.05 +/- 0.34 mg/dl) the therapy. As for the outcome at the end of this study setting (mean follow-up duration: 3.7 +/- 2.6 years), complete remission was attained in 7 cases, improvement in 5 cases, unchanged condition in 11 cases, increased urinary protein excretion in 2 cases and aggravated renal function in 1 case. In clinical findings at the renal biopsy, duration of the disease (3.4 +/- 1.6 months) in complete remission cases before biopsy was significantly (p less than 0.01) shorter than that in unchanged cases (65.0 +/- 40.0 months). In histological findings, rate of global sclerosing glomeruli (2.6 +/- 4.6%) in complete remission cases was significantly (p less than 0.05) lower than that (24.6 +/- 23.1%) in unchanged cases. These results suggest that steroid therapy in IgA nephropathy with persistent proteinuria of 1.0 g/day or more is beneficial, especially in cases that are in early stage of the disease with lower rate of global sclerosing glomeruli.

Adolescent↗
PubMed1992

[A case of familial lecithin: cholesterol acyltransferase deficiency].

Lecithin: cholesterol acyltransferase (LCAT) is an enzyme that catalyzes the esterifying reaction of cholesterol in plasma high density lipoprotein (HDL). Deficiency of LCAT is a rare hereditary disease characterized by several clinical symptoms such as proteinuria, corneal opacity, and anemia due to a shortened life span of erythrocytes. In this communication, we report a case of 40 year-old female patient of LCAT deficiency. She visited a hospital for work-up of proteinuria, corneal opacity and anemia. Activity of her serum LCAT was found to be extremely low, and characteristic changes in plasma lipids due to deficiency of LCAT was observed: those were marked decreases in HDL-cholesterol, degree of esterification in serum cholesterol, and apoprotein A-I, A-II, B and C-II levels. The diagnosis of LCAT deficiency was finally made. We studied about histopathological changes in the patient's kidney, and erythrocyte membrane lipid composition and fluidity. Histopathological findings in renal biopsy were follows: a) Light microscopy showed spherical deposits stained with periodic acid-Schiff in mesangial matrix and adjacent capillary loops, and hyaline deposits in arterioles, b) Electron microscopy showed vacuoles in mesangial matrix and along the glomerular basement membranes. In erythrocyte membrane lipids, increase of cholesterol to phospholipid molar ratio was evident, being accompanied by changes in phospholipid fractions: increase of phosphatidylcholine, and decreases of phosphatidylethanolamine, sphingomyelin and lysophosphatidylcholine. In phospholipid acyl chains, increase of C18:2 and decreased of C18:1 were evident in the patient. Erythrocyte membrane fluidity was found to be decreased in the patient in a measurement by pyrene, probably being related to the changes in membrane lipid composition.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Lupus nephritis with adult T cell leukemia.

A 64-year-old Japanese male patient with lupus nephritis associated with adult T cell leukemia (ATL) is described. Percutaneous renal biopsy demonstrated findings consistent with membranous lupus nephritis. To our knowledge, this is the first case of lupus nephritis complicated by ATL, suggesting that human T cell leukemia virus type I may be correlated not only to outbreaks of ATL but also to lupus nephritis/systemic lupus erythematosus.

Humans↗
PubMed1990

[A case of Fabry's disease detected by renal biopsy findings].

A 39 year-old man was found to have mild proteinuria by urinary examination since one year ago. He was for the first time diagnosed as having Fabry's disease by histopathological and electronmicroscopic findings of the renal biopsy specimens, which showed the presence of numerous vacuolated cells and electron dense bodies inside the cells. The level of WBC alpha-galactosidase was significantly lower than normal level. The pedigree of this patient showed a familial history of various types of renal disease. One of the patient's brothers also showed decreased level of WBC alpha-galactosidase, who has been treated by maintenance hemodialysis for 2 years. It is concluded that early diagnosis of this disease through renal biopsy and WBC alpha-galactosidase level is important to manage the future course of patients with Fabry's disease.

Adult↗
PubMed1989

Subpopulations of T alpha cells in patients with IgA nephropathy: correlation between T alpha 4 cells and in vitro IgA production.

T cells play important roles in the regulation of the immune system and are divided into subpopulations by various kinds of markers on the membrane surface. T cells with Fc-receptors for IgA are termed T alpha cells, and the properties of this cell population have been revealed in recent years. T alpha cells are increased in patients with IgA nephropathy and possess IgA specific helper activity. T alpha cells consist of two subpopulations, T alpha cells with OKT4 antigen (T alpha 4 cells) and with OKT8 antigen (T alpha 8 cells). To investigate the immunological aberrations in patients with IgA nephropathy, we detected immunoglobulin produced by peripheral blood lymphocytes and enumerated the numbers of T alpha cells (including both T alpha 4 and T alpha 8 cells). The numbers of T alpha 4 cells (but not T alpha 8 cells) and in vitro IgA production were increased in patients with IgA nephropathy (IgA nephropathy, mean 1.9%. Control, mean 0.8%. P = 0.0075). In addition, the numbers of T alpha 4 cells and the amount of IgA in the supernatant of lymphocyte cultures were positively correlated in these patients (P = 0.025. r = 0.3836). From the results in the present study, it was suggested that T alpha 4 cells might be related to immunological aberrations, such as an increase in IgA seen in patients with IgA nephropathy.

Adult↗