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Biomedical subjects

E Sugiyama

Publications and source records attributed to E Sugiyama.

At least 19 recordsLinked to original sources
PubMed2004

Effect of hematocrit on pharmacokinetics of tacrolimus in adult living donor liver transplant recipients.

OBJECTIVE: Plasma drug concentrations are generally considered to reflect efficacy and pharmacokinetics more directly than those in whole blood. However, whole blood has been selected as the matrix to monitor concentrations of tacrolimus (FK506), because it is difficult to accurately measure plasma FK506 concentrations. Because FK506 highly and saturably binds in blood cells, a change in hematocrit value (Hct) may affect FK506 pharmacokinetics. Therefore, we investigated effects of Hct on FK506 pharmacokinetics. METHODS: First, we analyzed data on FK506 distribution among human blood cells in vitro. Briefly, we employed an equation, which describes saturable binding of FK506 to blood cells, and simulated plasma FK506 concentrations and clearances using the above equation with respect to a variable Hct. Subsequently, we retrospectively analyzed dosages and whole blood FK506 concentrations to predict plasma FK506 concentrations in living donor transplant recipients. RESULTS: In the simulation study, the Hct changed plasma FK506 concentrations and clearances based in whole blood. In living donor liver transplant recipients, whole blood FK506 concentrations were maintained within a therapeutic range, while the Hct varied after transplantation. The correlation of Hct with the ratio of dose/trough concentrations of FK506 (D/C) in plasma (D/Cp) (R = -0.23, n = 343) was weaker than that for D/C in whole blood (D/CWB) (R = -0.53, n = 343). CONCLUSION: Hct may be an important factor affecting the pharmacokinetics of FK506 in living donor liver transplantation recipients. It may be necessary to take Hct into consideration in the FK506 dosing regimen, especially when the Hct is low.

Adult↗
PubMed2003

Resting T cells negatively regulate osteoclast generation from peripheral blood monocytes.

There is accumulating evidence that T cells may be involved in osteoclastogenesis in a variety of murine systems. However, the precise role of human T cells in the regulation of osteoclast generation is still unclear. To address this issue, we investigated the effect of resting peripheral T cells on receptor activator of NF-kappaB ligand (RANKL)-induced osteoclast generation from human peripheral monocytes. Although osteoclasts were not generated in the culture of human peripheral blood mononuclear cells (PBMC) in the presence of RANKL and macrophage colony-stimulating factor (M-CSF), the addition of cyclosporine A (CsA), a potent inhibitor of T-cell function, resulted in the formation of an increasing number of lacunae resorption on dentine, suggesting T cells may inhibit osteoclast formation. In a coculture of T cells and monocytes, which were isolated from PBMC, T cells inhibited the osteoclast generation from monocytes, as determined by tartrate-resistant acid phosphatase (TRAP) staining and a pit assay using dentine. This inhibition of osteoclast generation by T cells was also observed in a culture of the parathyroid hormone-stimulated SaOS4/3 osteoblast cell line and monocytes. The culture in Transwell plates revealed that the cell-to-cell interaction was not required for the inhibition, suggesting that T-cell cytokines may be responsible for the inhibition. Among inhibitory T-cell cytokines on osteoclastogenesis, granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon-gamma (IFN-gamma) were actively produced by CD4 T cells but not CD8 T cells in the coculture of T cells with monocytes, and the neutralizing antibodies to these cytokines partially rescued the T-cell-induced inhibition of osteoclast formation. Although CsA did not affect RANKL-induced osteoclast generation in the culture of monocytes alone, it completely rescued the T-cell-induced inhibition of osteoclast formation and strongly inhibited the production of GM-CSF and IFN-gamma. Thus, we demonstrate that resting T cells negatively regulate the osteoclast generation via production of GM-CSF and IFN-gamma by CD4 T cells and that CsA stimulates the osteoclast generation through the inhibition of the production of these cytokines. These findings provide new insight into therapeutic strategies for immunosuppression-induced bone loss in transplant and other diseases.

Bone Remodeling↗
PubMed2001

Hereditary angioedema with a de novo mutation of exon 8 in the C1 inhibitor gene showing recurrent edema of the hands around the peripheral joints: importance for the differential diagnosis of joint swelling.

We describe a patient with hereditary angioedema (HAE), showing recurrent edema around the peripheral joints. Her symptoms began at the age of 18 with hand swelling distal to the wrist joints. Until she was referred to our hospital 3 years after her initial symptoms, she was still undiagnosed, although she was suspected of having rheumatoid arthritis. Laboratory examination showed reduced levels of CH50 and C4 with normal C3 levels. The C1 inhibitor (C1-INH) was decreased to 5 mg/ml, with remarkably reduced activity. Although these findings were compatible with a diagnosis of HAE, there were no episodes of skin edema in her family. To establish the diagnosis, we carried out DNA analysis of the C1-INH gene, which revealed a newly identified de novo mutation of G to A at nucleotide 16869 in exon 8. As described in this patient, localized edema around the peripheral joints may be the only manifestation of HAE. HAE should therefore be taken into consideration for the differential diagnosis of joint swelling.

Adolescent↗
PubMed2001

Isolation of reducing oligosaccharide chains from the chondroitin/dermatan sulfate-protein linkage region and preparation of analytical probes by fluorescent labeling with 2-aminobenzamide.

The glycosaminoglycan (GAG)-protein linkage regions of various proteoglycans share the common tetrasaccharide GlcA-Gal-Gal-Xyl-attached to Ser residues in the core proteins. In previous analysis we demonstrated unique modifications by epimerization, sulfation and phosphorylation of the component sugars. Here we developed a sensitive analytical method for the linkage region oligosaccharides to detect or monitor structural variations and changes. This will be useful for investigation of their biological roles, which are largely unknown, but they have been implicated in biosynthesis. A variety of linkage region-derived hexasaccharides was first prepared as reducing sugar chains from peptide chondroitin/dermatan sulfate of whale cartilage, shark cartilage, and bovine aorta by means of chondroitinase digestion in conjunction with beta-elimination in the absence of reducing reagents, but involving a mild alkali, 0.5 M LiOH, at 4 degrees C to prevent peeling reactions. The structures of these oligosaccharides were determined by the combination of HPLC, enzymatic digestion, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, and (1)H NMR spectroscopy, which revealed eleven different hexasaccharides including a novel structure, DeltaHexAalpha1-3GalNAcbeta1-4IdoAalpha1-3Gal(4-O-sulfate)beta1-3Galbeta1-4Xyl (DeltaHexA and IdoA represent unsaturated hexuronic acid and L-iduronic acid, respectively). These oligosaccharides were labeled with a fluorophore, 2-aminobenzamide, to prepare analytical probes using the recently developed procedure [Kinoshita and Sugahara (1999) Anal. Biochem. 269, 367-378]. The fluorophore-tagged hexasacharides of low picomoles were well separated by HPLC and successfully analyzed by MALDI-TOF mass spectrometry. The principle of the method should be applicable to the analysis of the linkage region oligosaccharides derived from heparin and heparan sulfate as well.

Alkaline Phosphatase↗
PubMed2001

Ionizing radiation enhances matrix metalloproteinase-2 production in human lung epithelial cells.

Radiation pneumonitis is a major complication of radiation therapy. However, the detailed cellular mechanisms have not been clearly defined. Based on the recognition that basement membrane disruption occurs in acute lung injury and that matrix metalloproteinase (MMP)-2 can degrade type IV collagen, one of the major components of the basement membrane, we hypothesized that ionizing radiation would modulate MMP-2 production in human lung epithelial cells. To evaluate this, the modulation of MMP-2 with irradiation was investigated in normal human bronchial epithelial cells as well as in A549 cells. We measured the activity of MMP-2 in the conditioned medium with zymography and the MMP-2 mRNA level with RT-PCR. Both of these cells constitutively expressed 72-kDa gelatinolytic activity, corresponding to MMP-2, and exposure to radiation increased this activity. Consistent with the data of zymography, ionizing radiation increased the level of MMP-2 mRNA. This radiation-induced increase in MMP-2 expression was mediated via p53 because the p53 antisense oligonucleotide abolished the increase in MMP-2 activity as well as the accumulation of p53 after irradiation in A549 cells. These results indicate that MMP-2 expression by human lung epithelial cells is involved in radiation-induced lung injury.

Antisense Elements (Genetics)↗
PubMed2001

Confirmation of minor components of less polar neutral and acidic glycolipids in monkey brain tissue.

Crude glycolipids, prepared without alkali treatment in advance, were separated into neutral and acidic glycolipids by DEAE-Sephadex A-25 (acetate form) column chromatography. Each glycolipid was further fractionated by a Silica gel 60-column chromatography. By matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with delayed ion extraction (DE MALDI-TOF MS) of the intact glycolipid fractions, the less polar neutral glycolipids were found to contain alkali-labile ester cerebrosides and Galb-1-Diradylglycerols, whereas the less polar acidic glycolipids were found to contain alkali-labile ester sulfatide, HSO(3)-3Gal-1-Diradylglycerols, and novel alkali-stable plasmalo-sulfatides and ester or plasmalo HSO(3)-3Galb-1-Diradylglycerols as minor components of glycolipids in monkey brain tissue. In conclusion, minor components of less polar neutral and acidic glycolipids in monkey brain tissue were confirmed as ester cerebrosides, Galb-1-Diradylglycerols, ester sulfatides, HSO(3)-3Galb-1-Diradylglycerols, and novel plasmalo-sulfatides and ester or plasmalo HSO(3)-3Galb-1-Diradylglycerols by DE MALDI-TOF MS.

Animals↗
PubMed2000

Bradykinin stimulates IL-6 and IL-8 production by human lung fibroblasts through ERK- and p38 MAPK-dependent mechanisms.

Bradykinin (BK) is a major kinin with well-documented pharmacological properties including vascular leakage and induction of a variety of cytokines. However, the intracellular signalling mechanisms by which BK induced proinflammatory cytokine production have not been fully elucidated. This study investigated the role of the extracellular signal-regulated protein kinase 1/2 (ERK 1/2) and p38 mitogen-activated protein kinase (p38 MAPK) in the BK-induced interleukin (IL)-6 and IL-8 production by human lung fibroblasts. Lung fibroblasts were stimulated with BK in the presence or in the absence of PD98059, a specific MAPK/ERK kinase-1 inhibitor, or SB203580, a specific p38 MAPK inhibitor, and IL-6 or IL-8 production and their gene expression was examined. BK-induced ERK 1/2 or p38 MAPK phosphorylation was also analysed by Western blot analysis. BK at nanomolar concentrations stimulated lung fibroblasts to produce IL-6 and IL-8 along with increased ERK 1/2 and p38 MAPK phosphorylation. BK-induced IL-6 and IL-8 synthesis was inhibited by a B2-type BK receptor antagonist. Furthermore, PD98059 or SB203580 significantly suppressed BK-induced IL-6 and IL-8 production and their gene expression. These results indicate that bradykinin-induced interleukin-6 and interleukin-8 production are at least partly mediated through the extracellular signal-related protein kinase 1/2 and p38 mitogen-activated protein kinase pathway-dependent activation in human lung fibroblasts, and suggest that bradykinin appears to be involved in the inflammatory reaction leading to acute lung injury through stimulating interleukin-6 and interleukin-8 production by lung fibroblasts.

Blotting, Northern↗
PubMed2000

Interleukin-4 inhibits interleukin-11 production by rheumatoid synovial cells.

OBJECTIVE: To examine the effect of interleukin-4 (IL-4) on IL-11 production by rheumatoid synovial cells. METHODS: Freshly isolated rheumatoid synovial cells (FRS) were obtained by collagenase digestion of rheumatoid arthritis (RA) synovial tissue specimens taken at the time of operation. Rheumatoid synovial cells at four to eight passages were used as cultured rheumatoid synovial fibroblasts (RSF). IL-11 concentration was measured by ELISA. RESULTS: IL-4 inhibited the production of IL-11 by FRS in a dose-dependent manner. This inhibition was observed in FRS obtained from six patients, and the mean inhibition was 46.5%. The inhibitory effect of IL-4 on IL-11 production was cancelled by the addition of anti-IL-4 antibody. IL-4 also inhibited IL-11 production by IL-1alpha-stimulated cultured RSF. CONCLUSION: IL-4 inhibited IL-11 production by rheumatoid synovial cells. IL-4 has a protective effect on bone resorption. On the contrary, IL-11 participates in bone resorption via osteoclastogenesis. Therefore, IL-4 may exert its protective effect on bone resorption, at least in part, via inhibition of IL-11 production in rheumatoid joints.

Arthritis, Rheumatoid↗
PubMed2000

[A case of primary Sjögren's syndrome with interstitial pneumonia showing bronchiolitis obliterans organizing pneumonia pattern and lymphofollicular formation].

A 46-year-old woman with a 2-year history of xerostomia, who had had an episode of suspected Sjögren's syndrome in 1995, was admitted to our hospital because of a dry cough. Chest radiography on admission showed ground-glass infiltrates and reticular shadows in both lower lung fields. Primary Sjögren's syndrome was diagnosed by lip biopsy. Video-assisted thoracoscopic lung biopsies revealed the co-existence of interstitial pneumonia with the BOOP pattern and follicular bronchiolitis. Treatment with oral prednisolone improved the symptoms, and reduced the abnormal chest shadows. This was an interesting case of the BOOP pattern in a lung lesion associated with primary Sjögren's syndrome.

Administration, Oral↗
PubMed1999

A quantitative analysis of serum sulfatide by matrix-assisted laser desorption ionization time-of-flight mass spectrometry with delayed ion extraction.

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry with delayed ion extraction (DE MALDI-TOF MS) was applied for the first time for the quantitation of sulfatide content in serum at the picomole level. The total lipids extracted by n-hexane:isopropanol (3:2, v/v) from 100 microliter of serum were saponified to convert sulfatide to its lyso form, and then the lysosulfatide was directly determined using DE MALDI-TOF MS in the presence of other degraded lipids. Hydrogenated N-acetyl lysosulfatide was used as an internal standard. The relative peak height of sulfatide was calculated and plotted versus its contents. This plot showed linearity between 2 pmol and 1 nmol of sulfatide (regression coefficient r > 0.95). Sulfatide contents of normal human sera and rabbit serum were quantitated by this method. The results corresponded well to the reported data determined by gas-liquid chromatography. This new approach was found to be sensitive, convenient, and reliable. It is expected to be applied to quantitate sulfatide from other small amounts of body fluids or tissues and to clinical examination. It is also expected to be applicable to quantitate other glycosphingolipids.

Animals↗
PubMed1999

Tissue-non-specific alkaline phosphatase mRNA expression and alkaline phosphatase activity following application of retinoic acid in cultured human dental pulp cells.

Retinoic acid is a potent inducer of tissue-non-specific alkaline phosphatase (TNSALP) expression in various osteoblastic and fibroblastic cells, and may be involved in morphogenesis, cellular growth and differentiation. This study investigates the effects of retinoic acid on alkaline phosphatase activity and TNSALP gene expression in human dental pulp cells. Cultured cells were treated with various concentrations of retinoic acid (0, 10(-7), 10(- 6), 10 (-5) M) in 0.5% bovine serum albumin without serum. Alkaline phosphatase activity was determined by the rate of p-nitrophenyl phosphate hydrolysis and was also assayed in the presence of various inhibitors and under thermal inactivation. A set of specific oligonucleotide primers was selected, based on the nucleotide sequences of two human TNSALP mRNA (bone and liver) types, and reverse transcription-polymerase chain reaction (RT-PCR) performed. Inhibitory and thermal inactivation experiments revealed that the elevated alkaline phosphatase activity had properties of the TNSALP type. RT-PCR showed that retinoic acid enhanced the expression of bone-type TNSALP mRNA in pulp cells. However, the liver-type TNSALP mRNA was not detected. These findings suggest that the high alkaline phosphatase activity of retinoic acid-treated dental pulp cells is associated with increased transcription of the bone-type mRNA of the TNSALP gene and not with liver-type.

Alkaline Phosphatase↗