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N Araki

Publications and source records attributed to N Araki.

At least 37 records · Page 2Linked to original sources
PubMed2001

Post-transfusion alloimmunization to granulocytes and platelets in Japanese patients as determined by the MPHA method.

The current occurrence of alloimmunization to granulocytes and platelets after blood transfusion is unclear due to the fact that antibody assays are cumbersome. Using the MPHA method with extracted granulocyte and platelet antigens, a randomized, blinded trial was conducted to investigate three types of alloantibodies in 431 Japanese patients receiving leukocyte-depleted blood transfusions prepared with or without our latest leukocyte-reduction filter. The frequency of granulocyte, platelet and HLA class I alloantibodies was 0.44%, 0.44% and 16.74%, respectively, in patients receiving non-filtered products and 0%, 0% and 0.49%, respectively, in patients receiving filtered products. The granulocyte antibody reacted with an antigen approximately of 51 KDa. The platelet-specific alloantibody was associated with GPIIb/IIIa and GPIa/IIa. The important factors affecting alloimmunization were the transfusion dose and the use of unfiltered platelet products.

Antibody Formation↗
PubMed2001

Detection of SYT-SSX fusion gene in peripheral blood from a patient with synovial sarcoma.

This report describes a case involving a 22-year-old pregnant woman with synovial sarcoma in the thigh. The patient recognized an elastic hard mass accompanied by a dull pain in the anteromedial portion of the right thigh. Magnetic resonance imaging delineated a deep soft-tissue mass measuring 9 x 7 x 6 cm. Histologic diagnosis of poorly differentiated synovial sarcoma was made based the results of an open biopsy. In this patient, the SYT-SSX fusion gene transcript was detected by nested polymerase chain reaction (PCR) in the peripheral blood collected before biopsy. Two months after wide local resection of the tumor, multiple lung metastases developed. This is the first reported case in which tumor cells were detected by nested PCR in the peripheral blood of a patient with synovial sarcoma. These findings suggest that circulating tumor cells should be monitored because they may serve as a prognostic indicator for synovial sarcoma.

Adult↗
PubMed2001

Malignant mesenchymoma of the lower leg.

A 24 year old man had a two year history of a painless mass on his right popliteal region. Magnetic resonance imaging demonstrated a 6 x 8 cm tumour mass in the lateral gastrocnemius. Histological examination of the tumour resected by radical surgery revealed that it consisted of myoblastic sarcoma and chondrosarcoma. Immunohistochemical studies were positive for Ki-67 and p53 throughout the area and for S-100 protein in the chondrosarcomatous area; in addition, they showed partial positivity for muscle common actin (HHF-35), smooth muscle actin, and myoglobin in the spindle cells. The percentages of Ki-67, p53, and p21/WAF1 positive cells in the spindle cell component were 34%, 65.7%, and < 0.1%, respectively. In addition, staining was negative for pancytokeratin, desmin, and glial fibrillary acidic protein. The SYT-SSX, TLS-CHOP, and EWS-FLI1 fusion genes were not detected using the reverse transcription polymerase chain reaction. Given the results, the definitive histological diagnosis is malignant mesenchymoma. This is the first report of malignant mesenchymoma of the lower leg with immunohistochemical and molecular studies.

Adult↗
PubMed2001

Intramuscular haemangioma adjacent to the bone surface with periosteal reaction. Report of three cases and review of the literature.

We present three cases of intramuscular haemangioma adjacent to bone in the lower limb. All patients had local pain during the third decade. Plain radiographs showed an irregular or hypertrophic periosteal reaction on the shaft of the fibula and an intramuscular mass adjacent to the bone with inhomogeneous high signal intensity on MRI. These lesions mimic periosteal or parosteal tumours.

Adult↗
PubMed2001

Inhibition of nitric oxide production during global ischemia ameliorates ischemic damage of pyramidal neurons in the hippocampus.

We examined the relationship between nitric oxide (NO) production and delayed neuronal death (DND), in the rat hippocampus induced by 21 minutes of transient global ischemia produced by the occlusion of both of the common carotid arteries combined with systemic hypotension. NO production during ischemia and reperfusion was investigated by quantifying the nitrite (NO2-) levels of the in vivo microdialysis samples collected ever 3 minutes from the hippocampus. To determine the origin of NO production, we studied the effects of the focal administration of NG-nitro-L-arginine methyl ester (L-NAME), an inhibitor of the constitutive NO synthase (NOS). We also carried out systemic administration of a selective neuronal NOS inhibitor, 7-nitroindazole (7-NI). Rats were grouped as follows: group 1 (n = 22), vehicle; group 2 (n = 19), L-NAME; group 3 (n = 12), 7-NI; and group 4 (n = 12), a sham operation. The role of NO in the hippocampal DND was investigated histologically one week after ischemia. The level of NO production was significantly decreased in groups 2 and 3 as compared to group 1 in which NO production was significantly increased (p < 0.05). The density of remaining neurons in the CA1 area was significantly reduced only in group 1 (p < 0.01). Taken together, it can be concluded that NO production by neuronal NOS during ischemia and reperfusion resulted in DND in the CA1 region of the rat hippocampus.

Animals↗
PubMed2000

SYT-SSX fusion proteins in synovial sarcomas: detection and characterization with new antibodies.

To identify and characterize the SYT-SSX fusion proteins in synovial sarcomas, we developed two polyclonal antibodies against the N-terminal part and for the C-terminal part of the SYT-SSX2 protein. Specificity was demonstrated on COS-7 cells transfected with two subtypes of SYT-SSX fusion genes, SYT-SSX1 and SYT-SSX2. Both antibodies recognized a single protein of 61 kDa in an immunoprecipitation of the transfected COS-7 cell lysates. These antibodies also detected the native protein of 61 kDa in the lysate of a human synovial sarcoma cell line (HS-SY41) with immunoprecipitation, and in extracts of human synovial sarcomas with western blot analysis. An immunohistochemical study, using human synovial sarcoma tissues, demonstrated that the SYT-SSX fusion proteins localized in the nucleus of the tumor cells. These antibodies provide a useful method for studying the expression of the SYT-SSX fusion proteins.

Antibodies, Neoplasm↗
PubMed2000

Comparative analysis of brain proteins from p53-deficient mice by two-dimensional electrophoresis.

p53 is a tumor suppressor protein that regulates many cellular processes including the cell cycle, DNA repair, and apoptosis. It also serves as a critical regulator of neuronal apoptosis in the central nervous system (CNS). To elucidate the role of p53 in the CNS, brain proteins of p53 knock-out mice (p53-/-) were analyzed by two-dimensional gel electrophoresis (2-DE) and compared with those from p53 wild type (p53+/+) mice. Six types of brain tissue (temporal cortex, cerebellum, hippocampus, striatum, olfactory bulb, and cervical spinal cord) and other control tissues (lung and blood) from 18-week-old non-stress-induced mice were analyzed. The morphology of brains from p53-/- mice appeared to be normal and identical to that of p53+/+ mice, although lungs showed diffuse tumors that may have been caused by p53 deficiency. Comparative 2-D gel analysis showed that, on average, 7 of 886 spots from brain tissue were p53-/- specific, whereas 12 of 1008 spots from lung tissue were p53-/- specific. N-terminal amino acid sequence was determined for p53-/- specific proteins. In all brain tissues from p53-/- mice, a newly identified mouse mitochondrial NADH-ubiquinone oxidoreductase 24 kDa subunit showed decreased expression, and apolipoprotein A1 acidic forms showed increased expression. In addition, brain-type creatine kinase B chain and tubulin beta-5 N-terminal fragment were increased in the p53-/- cerebellum, and a new protein in mouse, hydroxyacylglutathione hydrolase (glyoxalase II) was decreased in the temporal cortex of p53-/- mice. The alterations in protein expression identified in this study may imply a p53-related brain function. This is the first proteomic analysis on the p53-/- mouse brain, and further information based on this study will provide new insights into the p53 function in the CNS.

Amino Acid Sequence↗
PubMed2000

Molecular diagnosis and gene therapy in musculoskeletal tumors.

Significant progress has occurred in the molecular analyses of bone and soft-tissue tumors, and genetic studies have led to the development of important new diagnostic tools for the clinical management of patients with sarcomas. The detection of fusion genes induced by tumor-specific translocations, such as EWS-FLI1 in Ewing's sarcoma, SYT-SSX in synovial sarcoma, and CHOP-FUS in myxoid liposarcoma, is becoming significant for clinical diagnosis, because these sarcomas are often indistinguishable from other bone and soft-tissue tumors. Gene therapies with several gene transfer systems have been employed for some incurable cancers. It has been demonstrated that a Herpes simplex virus thymidine kinase (HSV-tk) gene can convert certain nucleoside analogs, such as ganciclovir, which disrupt DNA synthesis and are toxic to nucleosides. Human chondrosarcoma cells transduced with the HSV-tk gene were more sensitive to the cytotoxity of ganciclovir than non-transduced cells. Coculture of chondrosarcoma cells with and without the HSV-tk gene showed a bystander effect. The local injection of gene transduced cells into the chondrosarcoma implanted in nude mice markedly reduced tumor size after the administration of ganciclovir. These results suggested the possibility of gene therapy for chondrosarcoma.

Animals↗
PubMed2000

Increased levels of advanced glycosylation end products in the kidney and liver from spontaneously diabetic Chinese hamsters determined by immunochemical assay.

Increased levels of advanced glycosylation end products (AGEs) have been reported in tissues in association with diabetes mellitus. Thus, we measured tissue AGE levels and detected an accumulation of AGEs in the kidney and liver from spontaneously diabetic Chinese hamsters (CHAD) to determine the relationship between AGEs and diabetes mellitus. Diabetic CHAD aged 12 to 13 months were studied together with age-matched nondiabetic CHAD. We used an AGE-specific noncompetitive enzyme-linked immunosorbent assay (ELISA) with polyclonal anti-AGE-bovine serum albumin (BSA) antibody to measure tissue AGE levels. The samples extracted from the kidney and liver obtained from diabetic and nondiabetic CHAD reacted with anti-AGE-BSA antibody. When the absorbance of standard AGE-BSA (0.1 microg/mL) was expressed as 1 U, AGE levels in the kidney and liver from diabetic CHAD were significantly increased as compared with nondiabetic CHAD (kidney, 0.26 +/- 0.05 v 0.10 +/- 0.03 U/microg protein, P< .01; liver, 0.20 +/- 0.03 v 0.09 +/- 0.02 U/microg protein, P< .01). Positive AGE staining was observed in the renal cortex, especially in the tubules of diabetic CHAD, but little AGE staining was observed in the glomerulus by the immunohistochemical study. AGE staining was diffuse in the hepatocytes. These AGE levels were significantly correlated with fasting plasma glucose and glycated hemoglobin (P < .01, respectively). In conclusion, we have confirmed that AGE structures were expressed in the kidney and liver from CHAD, and these AGE levels were increased in diabetic CHAD. AGE staining was observed in the renal tubules and hepatocytes. Tissue AGE levels were positively correlated with glycemic control in CHAD.

Animals↗
PubMed2000

Neonatal thrombocytopenia induced by maternal anti-HLA antibodies: a potential side effect of allogenic leukocyte immunization for unexplained recurrent aborters.

Allogenic leukocyte immunization is one of several treatments tried for unexplained recurrent aborters, and is reported to have few maternal and neonatal side effects after the immunotherapy having been reported to date. In the present study, we report a rare case of neonatal thrombocytopenia (41000 cells/microl) observed in a female infant delivered by an unexplained habitual aborter. The mother was immunized with her husband's leukocytes once before pregnancy and twice at the 5th and 6th week of her successful pregnancy. Serological studies using mixed passive hemagglutination assays (MPHA) showed that maternal serum did not contain any antibodies which were reactive to 11 platelet-specific antigens, or to granulocyte antigens extracted from 9 persons. Lymphocyte cytotoxicity tests, however, showed that maternal serum but not infant serum had anti-HLA antibodies against both paternal and infant lymphocytes. Moreover, the maternal serum was found to have anti-HLA IgGs against platelet antigens extracted from the father and the infant. It is highly likely that this case of neonatal thrombocytopenia was caused by transplacental perfusion of maternal anti-HLA antibodies whose production was induced or enhanced by the allogenic leukocytes immunizations.

Abortion, Habitual↗
PubMed2000

Reproducibility of geometric distortion in magnetic resonance imaging based on phantom studies.

BACKGROUND AND PURPOSE: Image distortion is one of the major drawbacks of magnetic resonance (MR) imaging for use in radiotherapy treatment planning (RTTP). In this study, the reproducibility of MR imaging distortion was evaluated by repeated phantom measurements. MATERIALS AND METHODS: A grid-pattern acrylic phantom was scanned with a 0.2-Tesla permanent magnetic unit. We repeated a series of scans three times to evaluate the reproducibility of the distortion. In each series, co-ordinates at 432 intersections of the grid were measured for both T1- and T2-weighted spin-echo (SE) pulse sequences. Positional displacements and their variations at the intersections were calculated. RESULTS: Averages of the displacements were distributed between 1.58 and 1.74 mm, and maximum values (MAX) between 12.6 and 15.0 mm. Within 120 mm of the image center, the average values ranged from 0.73 to 0.80 mm, and from 3.4 to 5.0 mm for MAX. The absolute values of the positional variations among three series were distributed between 0.41 and 0.88 mm for average values, and between 1.4 and 4.5 mm for MAX. CONCLUSIONS: The positional variations were mostly within 3 pixels, and most of the positional displacements within the radius of 120 mm of the image center were 2 mm or less. Therefore, it will be possible to use this MR system in RTTP under limited situations, although careful applications are required for RTTP of the body. The development of a computer program to correct image distortion is expected.

Artifacts↗
PubMed2000

Neoadjuvant chemotherapy by transcatheter arterial infusion method for uterine cervical cancer.

PURPOSE: The effects of transcatheter intraarterial infusion of anticancer drugs on the prognosis of cervical cancer were retrospectively studied. MATERIALS AND METHODS: Two or three sessions of transcatheter arterial infusion therapy were performed in 97 patients with primary uterine cervical cancer. The number of patients in stage I, II, III, or IV were 15, 37, 34, and 11, respectively. The drugs infused were cisplatin (60-70 mg/m2), doxorubicin hydrochloride (30-40 mg/m2), mitomycin (15 mg/m2), and 5-fluorouracil (500 mg/body). They were infused via the bilateral internal iliac arteries. Seventy-five patients of the 97 (78%) underwent radical hysterectomy after arterial infusion: stage I (14 of 15), stage II (31 of 37), stage III (25 of 34), and stage IV (5 of 11). Three stage II and nine stage III patients received radical radiation therapy. The other 10 patients (one with stage I, three with stage II, and six with stage IV) did not receive an operation and radiation therapy after arterial infusion because of their distant metastases at the time of operation. Thirty-eight patients of 75 (51%) received postoperative radiation therapy. RESULTS: The complete histologic response rates (no active cancer cells) after arterial infusion were four of 14, four of 31, six of 25, and one of five for stages I, II, III, and IV. The histologic response rates, which showed no parametrial invasion after arterial infusion, were 12 of 14, 24 of 31, and 15 of 25 for stages I, II, and III. The histologic response rates, which demonstrated no lymph node metastases after arterial infusion, were 12 of 14, 24 of 31, and 19 of 25 for stages I, II, and III. The overall 5-year survival rates of the patients with stages I, II, and III were 93.3%, 58.7%, and 69.7%, respectively. The 5-year survival rates of the operated patients with stages I, II, and III were 100%, 60.5%, and 63.6%, respectively. The 5-year survival rates of the irradiated patients with stage III was 87.5%. Leukocytopenia and thrombocytopenia occurred as an acute complication in 75% and 79% of the patients, respectively. As a late complication, ileus occurred in 7%. CONCLUSION: Arterial infusion may improve the prognosis of patients with cervical cancer without increasing the incidence of late complications.

Adenocarcinoma↗
PubMed2000

Actinin-4 is preferentially involved in circular ruffling and macropinocytosis in mouse macrophages: analysis by fluorescence ratio imaging.

We have applied fluorescence ratio imaging to the analysis of an actin-binding protein concentration relative to F-actin in macrophages, in order to explore the role of a novel (alpha)-actinin isoform, actinin-4, relative to that of the classical isoform, actinin-1. Conventional immunofluorescence images showed that both isoforms were enriched in F-actin-rich regions such as cell surface ruffles. However, ratio images further demonstrated that actinin-4 concentrations relative to F-actin were higher in peripheral inward curved ruffles and dorsal circular ruffles, presumed precursor forms of macropinosomes, than in straight linear ruffles, while actinin-1 concentrations were uniform among the different types of ruffles. Macropinosome pulse-labeling and chase experiments indicated that actinin-4 was also closely associated with newly formed macropinosomes and gradually dissociated with their maturation. Consistent with ratio imaging data, macrophages scrape-loaded with anti-actinin-4 showed a more reduced rate of macropinocytosis than those loaded with anti-actinin-1. Altogether, these results indicate that actinin-4 and actinin-1 contribute differently to F-actin dynamics, that actinin-4 is more preferentially involved in early stages of macropinocytosis than actinin-1. A similar redistribution of actinin-4 was also observed during phagocytosis, suggesting that actinin-4 may play the same role in the two mechanistically analogous types of endocytosis, i.e. macropinocytosis and phagocytosis.

Actinin↗
PubMed2000

Clinical significance of tenascin-C expression in osteosarcoma: tenascin-C promotes distant metastases of osteosarcoma.

Tenascin-C (TN-C) is one of extracellular matrix glycoproteins. We have immunohistochemically examined the TN-C expression of 33 primary osteosarcoma paraffin-embedded samples. The TN-C expression of the patient group with metastases was higher than that of the group without metastases at significant difference, and the survival curves show a tendency for poor outcome in the high grade staining group. Moreover, the supplemental TN-C had an effect of easier migration of a human osteosarcoma cell line (HOS) in vitro. The results may suggest that TN-C help osteosarcoma cells to migrate and to metastasize.

Adolescent↗
PubMed1999

Calcium influx triggers the sequential proteolysis of extracellular and cytoplasmic domains of E-cadherin, leading to loss of beta-catenin from cell-cell contacts.

Cadherins are major cell-cell adhesion molecules in both tumor and normal tissues. Although serum levels of soluble E-cadherin have been shown to be higher in the cancer patients than in healthy volunteers, the detail mechanism regulating release of soluble E-cadherin remains to be elucidated. Here we show that the ectodomain of E-cadherin is proteolytically cleaved from some cancer cells by a membrane-bound metalloprotease to yield soluble form, and the residual membrane-tethered cleavage product is subsequently degraded by intracellular proteolytic pathway. Futhermore, we show that extracellular calcium influx, that is induced by mechanical scraping of cells or ionomycin treatment, enhances the metalloprotease-mediated E-cadherin cleavage and the subsequent degradation of the cytoplasmic domain. Immunocytochemical analysis demonstrates that the sequential proteolysis of E-cadherin triggered by the calcium influx results in translocation of beta-catenin from the cell-cell contacts to cytoplasm. Our data suggest that calcium influx-induced proteolysis of E-cadherin not only disrupts the cell-cell adhesion but also activates beta-catenin-mediated intracellular signaling pathway, potentially leading to alterations in motility and proliferation activity of cells.

Base Sequence↗