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Biomedical subjects

K Tsuboi

Publications and source records attributed to K Tsuboi.

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

[Secondary eosinophilia in a patient with hypereosinophilic syndrome after allogeneic bone marrow transplantation from a sibling donor].

A 23-year-old man first visited a local hospital in 1998 because of exertional dyspnea. Peripheral blood examination revealed mild leukocytosis with 82% eosinophils, and he was treated with prednisolone. As the eosinophilia did not improve, he was referred to Tokai University Hospital in March 1999 for further diagnosis and treatment. The patient was diagnosed as having hypereosinophilic syndrome (HES) because of unexplained hypereosinophilia persisting for more than 6 months, resulting in cardiac dysfunction. His disease was progressive in spite of immunosuppressive therapy, interferon-alpha and cytotoxic chemotherapy. Since he had an HLA-identical brother, allogeneic bone marrow transplantation (BMT) was performed in October 1999. After completion of the immunosuppressive therapy on day 79 after BMT, the number of eosinophils gradually increased again. Although we suspected recurrence of the disease, DNA fingerprinting revealed that the peripheral granulocytes were 100% donor type. An increase of interleukin-5 (IL-5) produced by peripheral lymphocytes and a decrease of the Th1/2 ratio suggested that the eosinophilia was related to GVHD. The eosinophilia was eventually controlled by cyclosporin. We conclude that DNA fingerprinting and examination of the IL-5 level and Th1/2 ratio are useful for differentiating between relapse and GVHD in cases of eosinophilia occurring after BMT for HES.

Adult↗
PubMed2001

[Panic disorder and antidepressants].

Anxiety disorders, specifically, panic disorder, are the most common mental health disorders. Unless the clinician has a high index of suspicion, panic disorder or social anxiety disorder may remain undetected. Although quality of life(QOL) issues have long been recognized in severe psychiatric disorders, they have only recently come to be considered for the anxiety disorders. While the older tricyclic antidepressants(TCAs) are efficacious in the treatment of theses anxiety disorders, recent studies with paroxetine and other selective serotonin reuptake inhibitors(SSRIs) have emphasized the role of serotonin in the aetiology of these conditions. Both the TCA and SSRI antidepressants are effective in treating a wide variety of anxiety disorders. SSRIs, due to their greater safety and tolerability, should be the preferred choices in treating anxiety disorders in those instances.

Antidepressive Agents, Tricyclic↗
PubMed2001

[Hypotension].

Explore the source record for details and available documents.

Adolescent↗
PubMed2000

Fibroblast growth factor-2-producing fibroblasts protect the nigrostriatal dopaminergic system from 6-hydroxydopamine.

We tested the hypothesis that fibroblasts, which had been genetically engineered to produce fibroblast growth factor-2 (FGF-2), can protect nigrostriatal dopaminergic neurons. Three groups of rats received either a burr hole only (n=5) or implantation of fibroblasts, which had been genetically engineered to produce beta-galactosidase (beta-gal) (n=8) or FGF-2 (n=8), at two sites in the right striatum. Two weeks later, the animals received an injection of 25 microg of 6-hydroxydopamine hydrobromide (6-OHDA) midway between the two implant sites. The group that received FGF-2-fibroblasts had significantly fewer apomorphine-induced rotations than the groups that received a burr hole only or beta-gal-fibroblasts at weeks 2 and 3 following lesioning with 6-OHDA. Testing for amphetamine-induced rotation revealed a mild reduction in rotation in the beta-gal-fibroblast group compared to the burr hole only group, but a striking attenuation of amphetamine-induced rotation in the FGF-2-fibroblast group. There was also preservation of TH-IR neurons on the lesioned side relative to both control groups. The size of the grafts and the gliosis surrounding the injection sites did not differ between the FGF-2-fibroblast and beta-gal-fibroblast groups. To further characterize the production of FGF-2 by the FGF-2-fibroblasts, we implanted FGF-2-fibroblasts and beta-gal-fibroblast into the striatum of rats but did not lesion the animals with 6-OHDA. The animals were then sacrificed at 1, 2 and 5 weeks following implantation. Prior to implantation the FGF-2 fibroblasts contained 148 ng/mg of FGF-2-immunoreactive (FGF-2-IR) material per mg of protein of cell lysate. After implantation FGF-2-IR material was noted in the grafts of FGF-2-fibroblasts, most conspicuously at 1 and 2 weeks following implantation. We also noted FGF-2-IR material in the nuclei of reactive astrocytes adjacent to the implants, and OX-42-immunoreactive (OX-42-IR) cells adjacent and occasionally within the implants. Our work indicates that fibroblasts genetically engineered to produce FGF-2 and implanted in the striatum can protect the nigrostriatal dopaminergic system and may be useful in the treatment of Parkinson's disease.

Adrenergic Agents↗
PubMed2000

Effects of modification of the hydrophobic C-1-C-16 segment of tautomycin on its affinity to type-1 and type-2A protein phosphatases.

Among the naturally occurring toxins that are known to have specific inhibitory effects on type-1 and type-2A protein phosphatases (PP1 and PP2A), tautomycin (TM) is unique in that it exhibits significantly higher affinity to PP1 than to PP2A. The ratio of the dissociation constant for the PP1-TM interaction to that for the PP2A-TM interaction (the PP1/PP2A ratio) is 0.01-0.03. The aim of the present study was to evaluate the possible contributions of the C-1-C-16 segment of TM to the affinity characteristics of the toxin. The relatively hydrophobic segment contains a spiroketal motif whose enantiomeric form is present in okadaic acid (OA), which exhibits exceedingly higher affinity to PP2A than to PP1. We therefore synthesized two TM analogues: TM1 in which the side chains of the spiroketal motif of TM were removed but its absolute configuration was retained, and TM2 in which the spiroketal motif of TM1 was replaced with its enantiomeric form. The effects of TM, TM1 and TM2 on the activities of the native catalytic subunits of PP1 (PP1C) and PP2A and a recombinant gamma isoform of PP1 (PP1gamma) were examined. The PP1/PP2A ratio determined thereby was 0.2-0.5 for TM1 and 5-10 for TM2. Both the presence of the side chains and the stereochemistry of the spiroketal moieties may be major determining factors for the affinity characteristics of TM. We also show that a monoclonal antibody raised against OA binds to TM2 albeit with much lower affinity than to OA, whereas it exhibits no measurable affinities to TM and TM1.

Antifungal Agents↗
PubMed2000

Calretinin-containing axons and neurons are resistant to an intrastriatal 6-hydroxydopamine lesion.

Relative preservation of dopaminergic axons in patches and a subcallosal layer was observed in the dorsal, lateral and caudal striatum 4 weeks after intrastriatal injection of 6-hydroxydopamine (6-OHDA), a neurotoxin selective for catecholaminergic neurons. Since calcium binding proteins are reported to provide neuroprotective influence in neurons, differences in the distribution of the calcium binding proteins might be related to the different vulnerabilities of dopaminergic neurons and axons to neurotoxins. To address this possibility, we characterized patches of relatively dense tyrosine hydroxylase-immunoreactive (TH-IR) axons in intrastriatal 6-OHDA lesioned rats, focusing on two calcium binding proteins, calbindin (CB) and calretinin (CR). The patches and subcallosal layer of preserved dopaminergic axons in the striatum of rats lesioned with 6-OHDA contained CR, a 31-kDa calcium-binding protein, but interestingly not CB. Dopaminergic neurons containing CR in the substantia nigra pars compacta (SNpc) were relatively spared compared to those that did not contain CR. Taken together, our data indicate that dopaminergic axons and neurons containing CR in the nigrostriatal pathway are more resistant to 6-OHDA lesion than those that do not contain CR.

Animals↗
PubMed2000

Induction of superoxide in glioma cell line U87 stimulated with lipopolysaccharide and interferon-gamma: ESR using a new flow-type quartz cell.

The production of superoxide and nitric oxide induced in U87 glioma treated with lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) was examined by electron spin resonance (ESR) spectroscopy using a newly designed flow-type quartz cuvette without detaching cells from the culture plate. ESR spectra of 2,2,6, 6-tetramethyl-4-hydroxy-1-piperidinyloxy (TEMPOL) with U87 cells on a quartz culture plate were measured at 15 min intervals. The signal intensity of TEMPOL decreased in the presence of U87 cells at the pseudo-first order rate. The signal decay was accelerated in the U87 cells treated with LPS/IFN-gamma for 24 h, and was suppressed in the presence of superoxide dismutase and catalase. By the spin-trapping method, nitric oxide from U87 cells pretreated with LPS/IFN-gamma for 24 h was measured by the ESR, but only a weak signal of nitric oxide adducts was detected. Further, the nitrite and nitrate levels in the medium did not increase for 24 h. By the ESR measurement of cells on culture plates without detachment stress, it was found that the production of superoxide was induced by LPS/IFN-gamma, but that of nitric oxide was not, in U87 glioma cells.

Catalase↗
PubMed2000

Expression of the angiogenic factor thymidine phosphorylase in human astrocytic tumors.

Thymidine phosphorylase (TP) has been implicated as a potent angiogenic factor and a prognostic factor in various human solid tumors. We investigated the expression of TP in a series of human astrocytic tumors using immunohistochemistry, enzyme-linked immunosorbent assay, and reverse transcriptase/polymerase chain reaction (RT-PCR) analysis. A total of 63 astrocytic tumors [27 glioblastomas (GBM), 19 anaplastic astrocytomas (AA), 17 low-grade astrocytomas (LGA)] and 5 normal brain tissues were immunohistochemically stained with antibodies to TP, vascular endothelial growth factor (VEGF), p53, MIB-1, and factor-VIII-related antigen. They were also evaluated for the degree of apoptosis by a ApopTag kit. Ten tumors (5 GBM, 2 AA, 3 LGA) and 3 normal brain tissues were evaluated for their expression of VEGF and TP by RT-PCR analysis. TP was constantly localized in the cytoplasm of astrocytic tumor cells, less intensely in the cytoplasm of vascular endothelial cells, but not in the normal brain. Some of the TP-positive cells were of macrophage origin, but most positive cells were the tumor cells themselves. Vascular density, MIB-1 positivity, p53 positivity, VEGF expression, and the apoptotic index were significantly higher in the TP-positive tumors than in TP-negative tumors. There was a significant correlation between TP and VEGF mRNA expression. In a limited number of glioblastoma cases, the apoptotic index was significantly higher in TP-positive glioblastomas than in TP-negative glioblastomas. In human astrocytic tumors, TP was expressed in the tumor, macrophage, and endothelial cells. TP was a potent angiogenic factor closely associated with cell proliferation and tumor apoptosis.

Antigens, Nuclear↗
PubMed2000

Distal anterior choroidal artery aneurysm associated with an arteriovenous malformation. Intraoperative localization and treatment.

BACKGROUND: Distal anterior choroidal artery aneurysms are rare. The outcome of patients with distal anterior choroidal artery aneurysms has been poor, and the treatment of such aneurysms is surgically challenging. CASE DESCRIPTION: The authors describe the case of an 8-year-old girl with a ruptured distal anterior choroidal artery aneurysm associated with an arteriovenous malformation (AVM). The patient experienced sudden onset of headache and vomiting. Computed tomography revealed an intraventricular haemorrhage, and cerebral angiography demonstrated an aneurysm arising from the distal portion of the right anterior choroidal artery. The patient also had an AVM in the ipsilateral temporal lobe fed by the branches of the middle cerebral artery. A right frontotemporal craniotomy was performed with the aid of intraoperative angiography to eliminate both the AVM and the aneurysm. Intraoperative angiography was helpful in confirming the complete removal of the AVM and in accurate localization of the small and deeply placed distal anterior choroidal artery aneurysm. Both the AVM and the aneurysm were successfully treated and the patient was discharged without any neurological deficits. CONCLUSION: This case is the youngest reported patient with a distal anterior choroidal artery aneurysm. This report is also the first to describe an association of such an aneurysm with an AVM. The etiology of the aneurysm formation in this case and surgical strategy for deeply placed vascular lesions are discussed.

Aneurysm, Ruptured↗
PubMed2000

Role of phospholipase A2 in cholesterol gallstone formation is associated with biliary phospholipid species selection at the site of hepatic excretion: indirect evidence.

Phospholipase A2 plays a role in cholesterol gallstone development by hydrolyzing bile phospholipids into lysolecithin and free fatty acids. Lysolecithin and polyunsaturated free fatty acids are known to stimulate the synthesis and/or secretion of gallbladder mucin via a prostanoid pathway, leading to enhancing cholesterol crystal nucleation and growth, and therefore, the action of phospholipase A2 is associated, in part, with bile phospholipid fatty acid. To clarify this hypothesis, we evaluated the effect on bile lipid metastability in vitro of replacing phospholipids with lysolecithin and various free fatty acids. Supersaturated model biles were created with an identical composition (cholesterol saturation index, 1.8; egg yolk lecithin, 34 mM; taurocholate, 120 mM; cholesterol, 25 mM) except for 5%, 10%, or 20% replacement of egg yolk lecithin with a combination of palmitoyl-lysolecithin and a free fatty acid (palmitate, stearate, oleate, linoleate, or arachidonate), followed by time-sequentially monitoring of vesicles and cholesterol crystals using spectrophotometer and video-enhanced differential contrast microscopy. Replacement with hydrophilic fatty acids (linoleate and arachidonate) reduced vesicle formation and promoted cholesterol crystallization, whereas an enhanced cholesterol-holding capacity was evident after replacement with hydrophobic fatty acids (palmitate and stearate). These results indicate that the effect of phospholipase A2 on bile lithogenecity is modulated by the fatty acid species in bile phospholipids, and therefore, that the role of phospholipase A2 in cholesterol gallstone formation is dependent, in part, on biliary phospholipid species selection at the site of hepatic excretion.

Bile↗
PubMed2000

MUM1/IRF4 expression as a frequent event in mature lymphoid malignancies.

MUM1/IRF4 is a myeloma-associated oncogene transcriptionally activated as a result of t(6;14)(p25,q32) chromosomal translocation and by virtue of its juxtaposition to the immunoglobulin heavy chain gene (IgH) locus. When this oncogene becomes non-functional, no activated B/T lymphocytes and Ig secreting plasma cells are observed, suggesting that MUM1/IRF4 is crucial for lymphoid development. Its expression was analyzed in both reactive lymphoid and lymphoma tissues by means of an immunohistochemical technique using specific goat antiserum against MUM1/IRF4. This analysis detected a 50 kDa MUM1 product whose localization was restricted to the nuclei of the lymphocytes. The MUM1+ cells in reactive lymph nodes were found to consist of plasma cells and a small fraction (approximately 7.9%) of B cells harboring CD20+CD38+, which were located in the light zone of the germinal center. MUM1 expression in peripheral blood B/T lymphocytes was upregulated by mitogenic stimuli, suggesting that MUM1 positivity represents the activated state of the B/T cells. In B cell non-Hodgkin's lymphoma (NHL), MUM1 expression was observed in 73.2% (30/41) of diffuse large B cell lymphoma (DLBCL), 20% (1/5) of marginal zone lymphoma (MZL) and 43% (3/7) of small lymphocytic lymphoma (SLL) cases, whereas it was not seen in any cases of mantle cell lymphoma (MCL) or follicle center lymphoma (FCL). Also, MUM1 was stained at high intensity in various types of T cell lymphomas including adult T cell leukemia/lymphoma (ATL/L) and anaplastic large cell lymphoma (ALCL) and in the majority of Hodgkin's diseases. Our results suggest that a major proportion of lymphomas comprise either physiologically or aberrantly activated neoplastic lymphocytes expressing the MUM1 protein.

B-Lymphocytes↗
PubMed2000

Tissue factor, osteopontin, alphavbeta3 integrin expression in microvasculature of gliomas associated with vascular endothelial growth factor expression.

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor in human gliomas. VEGF-induced proteins in endothelial cells, tissue factor (TF), osteopontin (OPN) and alphavbeta3 integrin have been implicated as important molecules by which VEGF promotes angiogenesis in vivo. Sixty-eight gliomas were immunohistochemically stained with TF, VEGF, OPN and alphavbeta3 integrin antibody. Twenty-three tumours, six normal brains and nine glioma cell lines were evaluated for their mRNA expression of VEGF and TF by reverse transcription polymerase chain reaction analysis. The data indicated that TF as well as VEGF was a strong regulator of human glioma angiogenesis. First, TF expression in endothelial cells which was observed in 74% of glioblastomas, 54% of anaplastic astrocytomas and none of low-grade astrocytomas, correlated with the microvascular density of the tumours. Double staining for VEGF and TF demonstrated co-localization of these two proteins in the glioblastoma tissues. Second, there was a correlation between TF and VEGF mRNA expression in the glioma tissues. Third, glioma cell conditioned medium containing a large amount of VEGF up-regulated the TF mRNA expression in human umbilical vein endothelial cells. OPN and alphavbeta3 integrin, were also predominantly observed in the microvasculature of glioblastomas associated with VEGF expression. Microvascular expression of these molecules could be an effective antiangiogenesis target for human gliomas.

Brain Neoplasms↗
PubMed2000

Factors affecting gallstone recurrence after successful extracorporeal shock wave lithotripsy.

Ninety-six patients treated successively for symptomatic cholelithiasis with extracorporeal shock wave lithotripsy (ESWL) and oral bile acid therapy consisting of ursodeoxycholic acid in daily dosages of 600 mg were prospectively followed for gallstone recurrence for a median of 13 months. Ultrasonography was performed to detect stone recurrence at 3, 6, and 12 months, and then yearly after the termination of therapy. Recurrent stones were found in 17 patients (18%). The cumulative probability of gallstone recurrence was 15.8% at 12 months, 26.1% at 24 months, and 30.7% at 36 months. The probability of stone recurrence over the entire period of observation was not dependent on stone number, whereas the median interval to detection of recurrence was significantly shorter in the patients with multiple stones (2 months) than in those with solitary stones (8 months) (p < 0.05). The rate of impaired gallbladder contractility was higher in patients with recurrence (8/15, 53.3%) when compared with those with no recurrence (15/72, 20.8%) (p < 0.01). Neither age, gender, or stone characteristics predicted stone recurrence. Only one patient with a recurrence reported biliary pain. Of the 15 patients with recurrent stones who opted for further nonsurgical treatment, complete stone disappearance was achieved in 10. Impaired gallbladder function may predict gallstone recurrence after ESWL.

Cholagogues and Choleretics↗
PubMed2000

Uterine expression of prostaglandin H2 synthase in late pregnancy and during parturition in prostaglandin F receptor-deficient mice.

PG production in uterine tissues is important for many physiological processes in late pregnancy, including parturition. We examined the expression of the PGH2 synthases, cyclooxygenase-1 (COX-1) and COX-2, in uterine tissues during late pregnancy, using PGF receptor-deficient (FP-/-) mice. Female FP-/- mice are unable to deliver normal fetuses at term, as they do not undergo luteolysis necessary for parturition. In wild-type mice, COX-1 messenger RNA (mRNA) was expressed in the endometrial epithelium, myometrium, and decidua throughout late pregnancy. The expression of COX-1 mRNA in the endometrial epithelium and myometrium decreased both in wild-type mice undergoing natural parturition and in FP-/- mice undergoing ovariectomy-induced parturition, but expression of COX-1 mRNA was enhanced in FP-/- mice at the expected term. In wild-type mice, COX-2 mRNA was not expressed in the myometrium before parturition, but was markedly induced during parturition. This induction of COX-2 was absent in FP-/- mice at the expected term, but was found during ovariectomy-induced parturition in these mice. Expression of COX-2 proteins was confirmed by immunohistochemical analysis. Thus, in uterine tissues, myometrial expression of COX-2 is closely associated with the occurrence of parturition, but uterine expression of COX-1 is induced much earlier and kept at a high level until parturition occurs. These results suggest that COX-1-derived PGs are responsible for the induction of luteolysis, and that COX-2-derived PGs play a role in the final pathway of parturition.

Animals↗
PubMed2000

Superficially-located oligodendroglioma associated with intratumoral and peritumoral cysts--case report.

A 72-year-old male presented with a superficially-located oligodendroglioma associated with intratumoral and peritumoral cysts. Neuroimaging showed the outer cyst wall as enhanced but not the inner cyst wall. The outer cyst was removed and a biopsy taken of the solid component. The inner cyst wall appeared to consist of non-neoplastic tissue. Histological examination showed the tumor was an oligodendroglioma with tumor cells in the outer wall. The outer cyst was probably the result of blood-brain barrier disruption and intratumoral hemorrhage. The inner cyst probably resulted from reactive gliosis or peritumoral edema. Cyst formation in intraaxial tumors occurs through similar mechanisms to those of extraaxial tumors.

Aged↗
PubMed2000

Immunohistochemical and ultrastructural study of clinically nonfunctioning pituitary adenomas.

Sixty-five clinically nonfunctioning pituitary adenomas were studied by immunohistochemistry, and 12 cases were also analyzed by electron microscopy. Thirty-nine cases (60%) were immunohistochemically identified as hormone-producing adenomas. Six adenomas produced multiple hormones. Electron microscopy found seven null cell adenomas and five oncocytomas. The oncocytomas had a significantly higher incidence of hormone expression that the null cell adenomas. These results indicate that clinically nonfunctioning pituitary adenomas produce hormones, even though blood hormone levels are normal or low. Furthermore, the evidence of multihormonal production implies that two or more cell lineages including a protein hormone-producing type and a glycoprotein hormone-producing type may exist in the same nonfunctioning pituitary adenoma.

Adenoma↗
PubMed2000

A novel human multiple myeloma-derived cell line, NCU-MM-1, carrying t(2;11)(q11;q23) and t(8;22)(q24;q11) chromosomal translocations with overexpression of c-Myc protein.

A novel cell line, designated as NCU-MM-1, was established from a 66-year-old female patient with multiple myeloma (MM) that had shown rapid progression from solitary plasmacytoma to plasma cell leukemia. Interestingly, cytogenetic analysis including fluorescence in situ hybridization analysis disclosed that this cell line carried 2 kinds of chromosomal translocations involving immunoglobulin light chain (IgL) gene loci without the presence of 14q32 translocations (14q+). The Ig lambda locus juxtaposed to the c-MYC locus at 8q24 on the derivative (8) chromosome and a concomitant overexpression of the c-Myc protein was observed. On the derivative (11) chromosome, the Ig kappa locus was also fused to the chromosome 11q23 locus, which is known to be a nonrandom translocation breakpoint in mature B-cell malignancies. The NCU-MM-1 cell line may thus be useful not only for the identification of the responsible proto-oncogene(s) mapped to 11q23, deregulated by the Ig kappa enhancer sequences, but also for clarification of the molecular origin of MM lacking 14q+ chromosomes because IgL rearrangements can physiologically begin to occur in the pre-B-cell stage.

Aged↗