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Biomedical subjects

N Oda

Publications and source records attributed to N Oda.

At least 19 recordsLinked to original sources
PubMed2006

Inhibitory effects of fluvastatin on cytokine and chemokine production by peripheral blood mononuclear cells in patients with allergic asthma.

BACKGROUND: Statins have anti-inflammatory effects on immune cells. OBJECTIVE: To investigate the immunomodulatory effects of fluvastatin on peripheral blood mononuclear cells (PBMCs) after allergen-specific and non-allergen-specific stimulation in patients with asthma and in healthy subjects. METHODS: PBMCs from seven patients with asthma who showed elevated immunoglobulin (Ig)E to house dust mite were isolated and stimulated with Dermatofagoides farinae, purified protein derivative, and phytohaemagglutinin (PHA) in the presence or absence of fluvastatin. PBMCs from seven healthy subjects were stimulated with PHA. The effects of fluvastatin on cell proliferation and production of cytokines (interferon [IFN]-gamma and interleukin [IL]-5) and chemokines (chemokine CXC motif, ligand [CXCL10], and CC chemokine ligand [CCL17]) were measured. Migration of T helper (Th)1 and Th2 cell lines was also investigated. The expression of CXCR3 and CCR4 was analysed with flow cytometry. Steroid-insensitive PBMCs induced by preculture with IL-2 and IL-4 were also evaluated. Some experiments were performed in the presence of mevalonic acid. RESULTS: Fluvastatin inhibited the proliferation of PBMCs and decreased the production of IL-5, IFN-gamma, CCL17, and CXCL10 after allergen-specific and non-allergen-specific stimulation; all these effects, except for decreased CXCL10 production, were partially reversed by mevalonic acid. Culture supernatants obtained in the presence of fluvastatin prevented the migration of Th1 and Th2 cell lines in a dose-dependent manner. In addition, CCR4 and CXCR3 expression on CD4(+) T cells was not affected by the presence of fluvastatin. Fluvastatin inhibited the proliferative response of steroid-insensitive PBMCs to phytohaemagglutinin. CONCLUSION: Fluvastatin has inhibitory effects on cytokine and chemokine production, and thus might be used as a potential therapeutic agent in severe asthma.

Adult↗
PubMed2006

On-site treatment of turbid river water using chitosan, a natural organic polymer coagulant.

Chitosan, acetylate of chitin, is a biodegradable cationic polymer. The objective of this study is to assess the applicability of chitosan as an on-site treatment agent of turbid water caused by river construction works and other diffused pollutions. The results of jar-tests indicate that floc of chitosan is much larger than that of aluminium sulfate, and turbidity treated by chitosan under moving water conditions is much lower than that of aluminium sulfate. Chitosan is applied to Imou River in Yamaguchi prefecture, where river construction work is going on. St.1 is located just below the construction work, St.2 is located about 250 m downstream from St.1, and St.3 is located about 350 m downstream from St.2. Initial turbidity of each station is 1,100, 937 and 313 NTU, respectively. By applying chitosan at St.1, turbidity of each station is drastically reduced to 1,100, 12 and 0 NTU. Chitosan could be helpful to reduce problems caused by turbidity in rivers.

Alum Compounds↗
PubMed2004

A stable prostacyclin analogue reduces high serum TNF-alpha levels in diabetic patients.

AIMS: To confirm whether a prostacyclin (prostaglandin I (2)) affects the increased TNF-alpha concentration in sera of diabetic patients, we measured serum TNF-alpha concentration and treated these patients with oral administration of the stable prostacyclin analogue (Beraprost). Twelve of 20 type II diabetic patients were investigated for follow up-study and 6 of those patients were for therapy with Beraprost for diabetic neuropathy. SUBJECTS AND METHODS: Serum TNF-alpha concentration was quantified by EASIA using monoclonal antibodies directed against distinct epitopes of TNF-alpha. RESULTS: In diabetic patients, serum TNF-alpha concentration was significantly increased compared with that of healthy subjects. The augmented TNF-alpha concentration in these patients was not decreased by diabetic control using antihyperglycemic agents for 8 weeks but was reduced with oral administration of a stable prostacyclin (prostaglandin I (2)) analogue for 5 weeks without any changes of blood glucose levels. CONCLUSIONS: Stable prostacyclin analogue administration for a short term period reduced increased TNF-alpha levels in diabetic patients, not through the improved hyperglycemic condition but another pathway, probably a cAMP system. These results imply that treatment with the prostacyclin analogue may contribute to the prevention of progression in diabetic complications.

Adult↗
PubMed2004

Possible role of VEGF in the progression of kidney disease in streptozotocin (STZ)-induced diabetic rats: effects of an ACE inhibitor and an angiotensin II receptor antagonist.

Two endothelium-derived factors, endothelin (ET), a vasoconstrictor, and vascular endothelial growth factor (VEGF), an angiogenic factor are thought to be involved in the pathogenesis of diabetic vascular complications. The aim of this study was to determine the effects of an angiotensin II type I (AT-1) receptor antagonist and an ACE inhibitor on the pathogenesis of VEGF and ET-1-mediated kidney disease in STZ-induced diabetic rats. Two days after STZ administration, diabetic rats were treated for 8 weeks with enalapril maleate, an ACE inhibitor, candesartan cilexetil, an AT-1 receptor antagonist, or saline. Urinary albumin and N-acetyl beta-D glucosaminidase (NAG) excretion as well as the VEGF protein content in the kidney were all found to be elevated in diabetic rats. Administration of enalapril maleate or candesartan cilexetil decreased the level of microalbuminuria and NAG excretion in diabetic rats. Administration of enalapril maleate also suppressed the elevated renal VEGF protein content in these animals while candesartan cilexetil treatment had no effect. Serum ET-1 and VEGF levels were unchanged by these treatments. These data support a role for AT-1 receptor antagonists and ACE inhibitors in the prevention of diabetic nephropathy, and suggest that the former may work by reducing renal VEGF levels.

Albuminuria↗
PubMed2003

Laparoscopic gonadectomy in a case of a dicentric fluorescent Y-chromosome mosaicism with Turner-like phenotype and virilized external genitalia.

In few cases of Turner syndrome the karyotype reveals the presence of an additional Y-bearing cell line, which is referred to as a borderline case of mixed gonadal dysgenesis. We report a 20-year-old woman with primary amenorrhea, virilization and a few Turner stigmata, who revealed rare mosaicism of 45,X/46,X dic (Y; 5)(q12; q11), +5/46,X, der (Y), which was detected by conventional G-banding and multicolor spectral karyotyping. She underwent laparoscopic gonadectomy in which mixed gonadal dysgenesis was found and both gonads were removed. No evidence of gonadoblastoma was noted on the gonads. Virilization improved postoperatively. We recommend gonadectomy via laparoscope in women presenting with Turner-like phenotype, virilization and the presence of a Y chromosome. This report describes the role of cytogenetic and molecular genetic investigations in the definition of mosaicism in Turner syndrome.

Adult↗
PubMed2002

Experimental and theoretical studies of the effect of electrode polarisation on capacitances of blood and potassium chloride solution.

The effects of electrode polarisation on the observed capacitances of electrolytic solutions, including whole blood, plasma and potassium chloride solution, have been investigated experimentally in the frequency region from 10 to 10(5) Hz, by varying the area of the electrodes using plate and mesh electrodes, by varying the electrode distance, and by varying the concentration of KCl in the potassium chloride solution. The effects of the electrode polarisation on the observed capacitances were most significant in the frequencies lower than 10(2) Hz, but cannot be neglected in any frequency region. The so-called alpha dispersion observed in the frequencies lower than about 10(3) Hz was reproduced theoretically with an equivalent circuit model, using constant values independent of frequency for the four circuit parameters: sample capacitance, sample conductivity, electrode polarisation capacitance and electrode polarisation conductivity. It was concluded that the observed alpha dispersion is not a real one that represents the specific features of the samples themselves, but an apparent one that represents the characteristics of the whole measurement system, including the electrode polarisation.

Blood Physiological Phenomena↗
PubMed2002

Suplatast tosilate inhibits thymus- and activation-regulated chemokine production by antigen-specific human Th2 cells.

BACKGROUND: Suplatast tosilate is an anti-allergic agent that suppresses cytokine production by human Th2 cells. OBJECTIVE: We investigated the effects of suplatast tosilate on the production of thymus- and activation-regulated chemokine (TARC) by T cells from allergic patients with asthma. METHODS: Purified protein derivative (PPD)-specific Th1 cell lines and Dermatophagoides farinae (Der f)-specific Th2 cell lines were established from nine patients with house dust mite-allergic asthma. The effects of suplatast tosilate on mRNA expression of TARC and protein production of TARC from antigen-specific Th1 or Th2 cell lines were investigated after stimulation with relevant antigens or phytohemagglutinin (PHA). In addition, the effects of IL-4, IL-10, and IFN-gamma on TARC production by Der f-specific Th2 cell lines in the presence or absence of suplatast tosilate were studied. RESULTS: Although PPD-specific Th1 cell lines did not produce TARC after stimulation with PPD antigen or PHA, stimulation of Der f-specific Th2 cell lines with Der f antigen or PHA increased production of TARC. Suplatast tosilate significantly and dose-dependently inhibited production of TARC by Der f-specific Th2 cell lines stimulated with either Der f antigen (76.5% inhibition at 100 microg/mL, P < 0.01) or PHA (81.9% inhibition at 100 microg/mL, P < 0.01). TARC production by Der f-specific Th2 cell lines was significantly increased only by activation with IL-4 but not with IL-10 or IFN-gamma; this increase in TARC production was significantly inhibited by suplatast tosilate (97.5% inhibition at 100 microg/mL, P < 0.01). CONCLUSION: Suplatast tosilate inhibits TARC production by human Th2 cells. Therefore, this agent inhibits both Th2 cytokine and Th2 chemokine and may be a useful anti-allergic agent.

Adult↗
PubMed2002

Augmented binding and activation of latent transforming growth factor-beta by a tryptic fragment of latency associated peptide.

Transforming growth factor-beta (TGF-beta) is secreted in a latent form; thus, activation is critical for the control of TGF-beta action. Latent TGF-beta exists in a complex in which mature TGF-beta is noncovalently linked to latency associated peptide (LAP) and latent TGF-beta binding protein (LTBP) complex. We have shown that latent TGF-beta is efficiently activated in heterotypic cultures of endothelial cells (ECs) and smooth muscle cells (SMCs). Under those conditions, LAP plays an important role in targeting latent TGF-beta to the surface of SMCs, and plasmin and calpain target it to the surface of ECs for activation. Here, we demonstrate in a homotypic culture system that fragments of LAP increase the binding of latent TGF-beta to ECs, resulting in its activation by cell-associated proteolysis. LAP fragments appear to bind to the cell surface and augment the binding of latent TGF-beta, independent of transglutaminase. These results suggest a unique mechanism for the activation of latent TGF-beta by proteolytic fragments of LAP. The mechanism may arise from degradation by elevated levels of proteases under certain conditions.

Amino Acid Sequence↗
PubMed2001

Metallothionein expression and localization in rat bone tissue after cadmium injection.

We investigated the induction of metallothionein (MT) by cadmium (Cd) in the bone tissue of rats. To clarify the cell response to Cd in bone, the isoform-specific expression of MT mRNAs (MT-I and MT-II) was examined by reverse transcriptase-polymerase chain reaction (RT-PCR). Both MT-I and MT-II mRNA levels were increased within 3 h by Cd administration. MT (MT-I/MT-II) localization after single Cd injection were also confirmed by immunohistochemical studies. Notably, MT-positive cells were time-dependently increased, and the positive cells were mainly localized in osteocytes. The cell-specific induction of MT may be associated with Cd accumulation and Cd-induced bone injury in vivo. Furthermore, we also found that MT was consecutively expressed in some osteoclasts of control rats. This finding suggested a new role of osteoclasts in bone metabolism.

Animals↗
PubMed2001

A mechanism of the high frequency AC iontophoresis.

The efficiency and the voltage dependence of the AC iontophoresis were studied in vitro. Two cylindrical glass cells separated by a cellophane film were used, where the donor cell was filled with the solution of target electrolytes and the receptor cell with distilled water. The sinusoidal AC voltage with a frequency of 1 kHz was applied between the two platinum plates located at the opposite ends of two cells. The time variation of the ion concentration was evaluated by measuring the impedance of the solution in the receptor cell. The transportation velocity of the ions increased with the amplitude of the voltage applied between two platinum plate electrodes apart 20 mm up to approximately 15 V, and leveled off above approximately 15 V. A theoretical model is proposed on the AC iontophoresis, where each ion moves together with the surrounding water molecules when it is hydrated. The effective Stokes radius of an ion is assumed to be half of the whole size of the ion with hydrating water molecules. When the external alternating electric field strongly vibrates the ion, the ion-dipole interactions between the ion and water molecules are broken, resulting in the reduced effective Stokes radius, which leads to the increase of the diffusion efficiency.

Algorithms↗
PubMed2001

T-cell lines from 2 patients with adenosine deaminase (ADA) deficiency showed the restoration of ADA activity resulted from the reversion of an inherited mutation.

Inherited deficiency of adenosine deaminase (ADA) results in one of the autosomal recessive forms of severe combined immunodeficiency. This report discusses 2 patients with ADA deficiency from different families, in whom a possible reverse mutation had occurred. The novel mutations were identified in the ADA gene from the patients, and both their parents were revealed to be carriers. Unexpectedly, established patient T-cell lines, not B-cell lines, showed half-normal levels of ADA enzyme activity. Reevaluation of the mutations in these T-cell lines indicated that one of the inherited ADA gene mutations was reverted in both patients. At least one of the patients seemed to possess the revertant cells in vivo; however, the mutant cells might have overcome the revertant after receiving ADA enzyme replacement therapy. These findings may have significant implications regarding the prospects for stem cell gene therapy for ADA deficiency.

Adenosine Deaminase↗
PubMed2001

Weekly dosing with the platelet-derived growth factor receptor tyrosine kinase inhibitor SU9518 significantly inhibits arterial stenosis.

The platelet-derived growth factor (PDGF) ligands and their receptors have been implicated as critical regulators of the formation of arterial lesions after tissue injury. SU9518 (3[5-(5-bromo-2-oxo-1,2-dihydroindol-3-ylidenemethyl)-2,4-dimethyl-1H-pyrrol-3-yl]propionic acid) is a novel synthetic indolinone that potently and selectively inhibits the cellular PDGF receptor kinase and PDGF receptor-induced cell proliferation. Inhibition of PDGF receptor phosphorylation in cell-based assays occurs within 5 minutes after drug exposure and persists for >6 hours after drug removal. The pharmacokinetics indicate plasma levels that exceeded the effective concentration required to inhibit the PDGF receptor in cells for up to 8 hours or 7 days after a single oral or subcutaneous administration, respectively. In the rat balloon arterial injury-induced stenosis model, once-daily oral or once-weekly subcutaneous administration of SU9518 reduced intimal thickening of the carotid artery (ratio of neointimal to medial area, 1.94+/-0.38 versus 1.03+/-0.29 [P<0.01] 2.21+/-0.32 versus 1.34+/-0.45 [P<0.01], respectively). These studies provide the rationale to evaluate PDGF receptor tyrosine kinase inhibitors, including inhibitors related to the indolinone, SU9518, for the treatment of arterial restenosis.

3T3 Cells↗
PubMed2001

Opposing pharmacological actions of cepharanthin on lipopolysaccharide-induced histidine decarboxylase activity in mice spleens.

A biscoclaurin alkaloid preparation, cepharanthin (Ceph), is reported to have opposing pharmacological effects, enhancement or depression, on several cells and tissues, although detailed mechanisms remain unclear. Previously, we reported that Ceph enhanced lipopolysaccharide (LPS)-induced histidine decarboxylase (HDC) activity in mice spleens by consecutive pre-administration. In this study, we examined the pharmacological effects on HDC activity of a single Ceph pre-administration to test the influence of the administration method. Consequently, HDC activities were decreased by a single administration 15 minutes before LPS challenge in ddY and ICR mice spleens. Moreover, to further examine this suppressing effect, we employed genetically mast cell-deficient WBB6F1 W/Wv (W/Wv) mice to avoid the influence of mast cells. In W/Wv mice, HDC activity was enhanced, but not in the congenic WBB6F1 +/+ mice. These findings suggest that mast cells influence the depressant effect on HDC activity by a Ceph single administration in mast cell sufficient mice.

Alkaloids↗
PubMed2001

Molecular basis for paradoxical carriers of adenosine deaminase (ADA) deficiency that show extremely low levels of ADA activity in peripheral blood cells without immunodeficiency.

Adenosine deaminase (ADA) deficiency causes an autosomal recessive form of severe combined immunodeficiency and also less severe phenotypes, depending to a large degree on genotype. In general, ADA activity in cells of carriers is approximately half-normal. Unexpectedly, healthy first-degree relatives of two unrelated ADA-deficient severe combined immunodeficient patients (mother and brother in family I; mother in family II) had only 1-2% of normal ADA activity in PBMC, lower than has previously been found in PBMC of healthy individuals with so-called "partial ADA deficiency." The level of deoxyadenosine nucleotides in erythrocytes of these paradoxical carriers was slightly elevated, but much lower than levels found in immunodeficient patients with ADA deficiency. ADA activity in EBV-lymphoblastoid cell lines (LCL) and T cell lines established from these carriers was 10-20% of normal. Each of these carriers possessed two mutated ADA alleles. Expression of cloned mutant ADA cDNAs in an ADA-deletion strain of Escherichia coli indicated that the novel mutations G239S and M310T were responsible for the residual ADA activity. ADA activity in EBV-LCL extracts of the paradoxical carriers was much more labile than ADA from normal EBV-LCL. Immunoblotting suggested that this lability was due to denaturation rather than to degradation of the mutant protein. These results further define the threshold level of ADA activity necessary for sustaining immune function.

Adenosine Deaminase↗
PubMed2001

The effects of ovariectomy and female sex hormones on hepatic metallothionein-I gene expression after injection of cadmium chloride in mice.

Metallothioneins (MTs) have a low molecular weight and have been considered to be important metal-binding proteins in defense from cadmium (Cd) toxicity in animals. These proteins are known to be induced by the injection of heavy metals such as Cd. Previously, we developed the measurement of the MT mRNA expression by the RT-PCR method. In this study, to clarify the relation between Cd-induced MT-I mRNA expression and female sex hormones in liver, we investigated the influences of the ovariectomy and female sex hormones on hepatic MT-I mRNA expression after Cd injection, and also investigated the effects of aging on hepatic MT-I mRNA expression in mice after Cd injection. We analysed the MT-I mRNA expression by the RT-PCR method. Cd-induced MT-I mRNA expression in ovariectomized mice was more than that in sham-operated mice (9 weeks old). Both 17 beta -estradiol and progesterone reduced the Cd-induced MT-I mRNA expression in ovariectomized mice (9 weeks old). Moreover, the MT-I mRNA expression in male mice was more than that of females (9 weeks old). However, the sex difference in the gene expression was not found in younger (4 weeks old) or older (46 weeks old) mice. These results suggest that the expression of hepatic MT-I mRNA after Cd injection is influenced by female sex hormones.

Animals↗
PubMed2001

Atlantoaxial subluxation in an adult secondary to retropharyngeal abscess.

Atlantoaxial subluxation secondary to a retropharyngeal abscess is well described in children, but very rare in adults. Only two adult cases have been reported in the literature. We present a case of severe atlantoaxial subluxation in an adult secondary to retropharyngeal abscess. His atlas-dens interval was very large, up to 10 mm in flexion. We tried external fixation with a neck collar initially, but for remaining instability, surgical fusion was performed. The mechanism of subluxation is attributed to softening of the ligament allowing greater mobility at the joint. The etiology of this process is speculative.

Atlanto-Axial Joint↗