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1.
Nat Commun ; 10(1): 5266, 2019 11 20.
Article in English | MEDLINE | ID: mdl-31748566

ABSTRACT

Solid electrolytes are key materials to enable solid-state rechargeable batteries, a promising technology that could address the safety and energy density issues. Here, we report a sulfide sodium-ion conductor, Na2.88Sb0.88W0.12S4, with conductivity superior to that of the benchmark electrolyte, Li10GeP2S12. Partial substitution of antimony in Na3SbS4 with tungsten introduces sodium vacancies and tetragonal to cubic phase transition, giving rise to the highest room-temperature conductivity of 32 mS cm-1 for a sintered body, Na2.88Sb0.88W0.12S4. Moreover, this sulfide possesses additional advantages including stability against humid atmosphere and densification at much lower sintering temperatures than those (>1000 °C) of typical oxide sodium-ion conductors. The discovery of the fast sodium-ion conductors boosts the ongoing research for solid-state rechargeable battery technology with high safety, cost-effectiveness, large energy and power densities.

2.
Gen Physiol Biophys ; 20(2): 131-44, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11519685

ABSTRACT

Azalomycin F (AMF), a macrocyclic lactone antibiotic, in concentrations of 10(-5) g/ml (10(-6) - 10(-5) mol/l) was found to stimulate both the 45Ca2+ influx and efflux in intact Trichoderma viride submerged mycelium and in cells of Saccharomyces cerevisiae without having Ca2+ ionophoric properties. AMF also inhibited ATP-dependent Ca2+ uptake in membrane fractions prepared from T. viride submerged mycelium. 45Ca2+ which had been accumulated in membrane fractions in an ATP-dependent manner was released upon addition of AMF. This release was observed in light organellar fractions (LOF) of S. cerevisiae and of T. viride submerged mycelium and, to a small extent, in heavy organellar fraction (HOF) of S. cerevisiae. No Ca2+ releasing effect of AMF was observed in HOF from T. viride submerged mycelium. In S. cerevisiae expressing Ca2+-dependent photoprotein aequorin, AMF induced transients of luminescence which reflect changes in the cytoplasmic Ca2+ concentration. The results suggest that the stimulation by AMF of the Ca2+ efflux from the mycelium (cells) could be explained by an increase of the cytoplasmic Ca2+ concentration due to the release of Ca2+ from microsomal membranes or to the stimulation of Ca2+ influx.


Subject(s)
Anti-Bacterial Agents/pharmacology , Calcium/metabolism , Saccharomyces cerevisiae/drug effects , Trichoderma/drug effects , Biological Transport/drug effects , Cell Fractionation , Egtazic Acid/pharmacology , Homeostasis/drug effects , Homeostasis/physiology , Kinetics , Macrolides , Organelles/drug effects , Organelles/physiology , Saccharomyces cerevisiae/physiology , Subcellular Fractions/metabolism , Trichoderma/physiology
3.
Cell Struct Funct ; 25(2): 125-31, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10885582

ABSTRACT

The mating pheromone, alpha-factor, of the yeast Saccharomyces cerevisiae binds to the heterotrimeric G protein-coupled cell surface receptor of MATa cells and induces cellular responses necessary for mating. In higher eukaryotic cells, many hormones and growth factors rapidly mobilize a second messenger, Ca2+, by means of receptor-G protein signaling. Although striking similarities between the mechanisms of the receptor-G protein signaling in yeast and higher eukaryotes have long been known, it is still uncertain whether the pheromone rapidly mobilizes Ca2+ necessary for early events of the pheromone response. Here we reexamine this problem using sensitive methods for detecting Ca2+ fluxes and mobilization, and find no evidence that there is rapid Ca2+ influx leading to a rapid increase in the cytosolic free Ca2+ concentration. In addition, the yeast PLC1 deletion mutant lacking phosphoinositide-specific phospholipase C, a key enzyme for generating Ca2+ signals in higher eukaryotic cells, responds normally to the pheromone. These findings suggest that the receptor-G protein signaling does not utilize Ca2+ as a second messenger in the early stage of the pheromone response pathway. Since the receptor-G protein signaling does stimulate Ca2+ influx after early events have finished and this stimulation is essential for late events in the pheromone response pathway [Iida et al., (1990) J. Biol. Chem., 265: 13391-13399] Ca2+ may be used only once in the signal transduction pathway in unicellular eukaryotes such as yeast.


Subject(s)
Calcium Signaling , Calcium/metabolism , Peptides/metabolism , Receptors, Cell Surface/metabolism , Saccharomyces cerevisiae/physiology , Calcium Signaling/drug effects , Cell Cycle/drug effects , Cell Differentiation , Heterotrimeric GTP-Binding Proteins/metabolism , Mating Factor , Peptides/pharmacology , Plasmids/genetics , Second Messenger Systems , Signal Transduction , Type C Phospholipases/genetics
4.
Biol Pharm Bull ; 23(5): 663-5, 2000 May.
Article in English | MEDLINE | ID: mdl-10823686

ABSTRACT

We investigated the effects of various sulfhydryl compounds on interleukin-1 (IL-1)-induced vascular endothelial growth factor (VEGF) production in human synovial stromal cells (HSSC). HSSC stimulated by IL-1beta (100 ng/ml) produced VEGF and interleukin-6 (IL-6) in vitro. Monosulfhydryl compounds, N-acetylcysteine, D-penicillamine, tiopronin and the bucillamine-like disulfhydryl compound, compound A scarcely affected VEGF or IL-6 production at concentrations of 10(-5) and 10(-4) M. However, the disulfhydryl compound, bucillamine inhibited VEGF production but not IL-6 production at concentrations of 10(-5) and 10(-4) M. These results suggest that bucillamine may be a selective inhibitor of IL-1-induced VEGF production in HSSC, and that inhibition of VEGF production may require not only SH groups but also a specific chemical structure.


Subject(s)
Endothelial Growth Factors/biosynthesis , Lymphokines/biosynthesis , Sulfhydryl Compounds/pharmacology , Synovial Membrane/drug effects , Acetylcysteine/pharmacology , Cells, Cultured , Cysteine/analogs & derivatives , Cysteine/pharmacology , Humans , Interleukin-1/pharmacology , Penicillamine/pharmacology , Stromal Cells/drug effects , Stromal Cells/metabolism , Synovial Membrane/cytology , Tiopronin/pharmacology , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
5.
Surg Today ; 30(2): 153-8, 2000.
Article in English | MEDLINE | ID: mdl-10664339

ABSTRACT

The aim of this study was to evaluate whether or not perfusatory recovery of the grafted lung occurs is the early stage of convalesce from acute rejection following a single lung transplantation. Eight adult mongrel dogs underwent an allotransplantation of the left lung with treatment of 10 mg/kg cyclosporine and 4 mg/kg azathioprine. Doppler flow probes were placed to the ascending aorta and the left pulmonary artery. Immunosuppressant therapy was discontinued to induce rejection after postoperative day 14. When the left pulmonary artery flow rate (l-PAFR) decreased to less than 20%, methylprednisolone (20 mg/kg) was administered for 3 days along with a resumption of cyclosporine and azathioprine. Pulmonary circulation and chest roentgenograms were evaluated every day through the rejection episode. An open lung biopsy was also performed in each dog to obtain specimens of the grafts and native lungs for histologic examination. When l-PAFR decreased to less than 20%, mild acute rejection was found in all dogs. l-PAFR increased significantly on the third day after methylprednisolone treatment. Thereafter, a histologic examination revealed minimal acute rejection in one dog and no abnormality in seven dogs. The perfusatory recovery of the grafted lung was thought to reflect the histological change in the course of convalescence.


Subject(s)
Aorta, Thoracic/physiopathology , Graft Rejection/physiopathology , Lung Transplantation/physiology , Lung/blood supply , Pulmonary Artery/physiopathology , Pulmonary Circulation/physiology , Acute Disease , Animals , Aorta, Thoracic/diagnostic imaging , Azathioprine/therapeutic use , Blood Flow Velocity , Cyclosporine/therapeutic use , Dogs , Graft Rejection/pathology , Graft Rejection/prevention & control , Immunosuppressive Agents/therapeutic use , Laser-Doppler Flowmetry , Lung/pathology , Pulmonary Artery/diagnostic imaging , Transplantation, Homologous , Ultrasonography
6.
Immunol Lett ; 68(2-3): 275-9, 1999 Jun 01.
Article in English | MEDLINE | ID: mdl-10424432

ABSTRACT

The effects of mitogen-activated protein (MAP) kinase inhibitors or phosphodiesterase (PDE) inhibitors on interleukin (IL)-1-induced cytokines production in synovium-derived cells were investigated. Human synoviocyte (HS) or synovial sarcoma (SW982) stimulated by IL-1beta (100 ng/ml) produced various cytokines including IL-6, IL-8, GROalpha, VEGF, basic FGF and tumor necrosis factor alpha (TNFalpha) in vitro. SB202190 or SB203580, an inhibitor of p38 MAP kinase, inhibited all cytokines production in both cells. PD98059, an inhibitor of MAP kinase kinase (MEK), inhibited IL-6, IL-8 and basic FGF production in HS and all cytokines production except basic FGF in SW982. However, many of its effects were weaker than those of SB202190 or SB203580. Quazinone, an inhibitor of cyclic GMP-inhibited PDE, scarcely affected cytokines production in both cells. Rolipram or R0201724, an inhibitor of cyclic AMP-specific PDE, inhibited IL-8 and basic FGF production in HS and TNFalpha production in SW982, however, it enhanced the other cytokines production in SW982. These results suggest that the activation of MAP kinase cascade may be important for IL-1-induced cytokines production in synovium-derived cells. On the other hand, the role of cyclic AMP may be dependent on cell and cytokine types.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors , Cytokines/biosynthesis , Interleukin-1/pharmacology , Phosphodiesterase Inhibitors/pharmacology , Synovial Membrane/immunology , 4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone/pharmacology , Dose-Response Relationship, Drug , Humans , Imidazoles/pharmacology , Pyridines/pharmacology , Pyrrolidinones/pharmacology , Quinazolines/pharmacology , Rolipram , Synovial Membrane/cytology , Synovial Membrane/drug effects
7.
Clin Exp Immunol ; 115(1): 26-31, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9933417

ABSTRACT

We investigated the effects of bucillamine and N-acetyl-L-cysteine (NAC) on cytokine production and CIA. Bucillamine and NAC inhibited NF-kappaB activation and tumour necrosis factor-alpha (TNF-alpha) mRNA expression in human monocytic leukaemia cell line THP-1, and cytokine production from monocyte cell lines at concentrations >10-3 M. They also inhibited cytokine production and CIA in mice at a dose of 500 mg/kg. These results suggest that NF-kappaB inhibitors such as bucillamine and NAC may inhibit cytokine-related diseases, including arthritis.


Subject(s)
Acetylcysteine/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Arthritis, Experimental/drug therapy , Collagen , Cysteine/analogs & derivatives , Animals , Antibodies/blood , Arthritis, Experimental/chemically induced , Cholesterol/blood , Collagen/immunology , Cysteine/pharmacology , Humans , Male , Mice , Mice, Inbred DBA , NF-kappa B/metabolism , Phospholipids/blood , Rats , Rats, Wistar , Triglycerides/blood , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism
8.
Life Sci ; 64(3): PL51-6, 1999.
Article in English | MEDLINE | ID: mdl-10027755

ABSTRACT

We investigated the role of leukotriene B4 (LTB4) in murine arthritis models using a leukotriene A4 (LTA4) hydrolase inhibitor, SA6541. SA6541 inhibited the severity of collagen-induced arthritis and muramyl dipeptide (MDP)-induced hyperproliferation of synovial cells in vivo. SA6541 also inhibited LTA4-induced hyperproliferation of synovial stromal cells in vitro. These results suggest that LTB4 may play an important role in arthritis models.


Subject(s)
Aniline Compounds/pharmacology , Arthritis/drug therapy , Cysteine/analogs & derivatives , Disease Models, Animal , Leukotriene B4/physiology , Acetylmuramyl-Alanyl-Isoglutamine/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Arthritis/chemically induced , Arthritis/pathology , Body Weight/drug effects , Bone and Bones/drug effects , Bone and Bones/pathology , Cell Division/drug effects , Cell Survival/drug effects , Collagen , Cysteine/pharmacology , Epoxide Hydrolases/antagonists & inhibitors , Female , Mice , Mice, Inbred BALB C , Mice, Inbred DBA , Prednisolone/pharmacology , Stromal Cells/drug effects , Stromal Cells/pathology , Synovial Fluid/cytology , Tarsus, Animal
10.
Ocul Immunol Inflamm ; 6(1): 19-25, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9798190

ABSTRACT

The effects of tachykinins on prostaglandin E2 (PGE2)-induced intraocular inflammation were investigated. PGE2 (0.01% or 0.1%) instillation induced iridal hyperemia and protein leakage into the aqueous humor in rabbits, but caused minimal miosis. Intravitreally injected substance P (SP) or neurokinin A (NKA), on the other hand, did not induce protein leakage into the aqueous humor in normal rabbits, but they (SP 10 micrograms/eye or NKA 50 micrograms/eye) did induce long-lasting miosis. The miotic activity of SP was about fivefold stronger than that of NKA. Intravitreally injected SP (10 micrograms/eye) but not NKA (50 micrograms/eye) increased PGE2 concentration in the aqueous humor in normal rabbits. In addition, SP (10 micrograms/eye) or NKA (50 micrograms/eye) markedly enhanced protein leakage into the aqueous humor induced by PGE2 instillation. Pretreatment with indomethacin partially blocked the enhancing effect of SP on protein leakage, while it did not block that of NKA. These results suggest that SP or NKA may enhance intraocular inflammation in vivo. However, the mechanisms of these effects of SP and NKA may be different. The enhancing effect of SP in eye inflammation may be partially due to an increased turnover of arachidonic acid into PGE2 caused by activation of the enzyme cyclooxygenase.


Subject(s)
Dinoprostone , Endophthalmitis/chemically induced , Tachykinins/physiology , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aqueous Humor/metabolism , Dinoprostone/pharmacology , Dose-Response Relationship, Drug , Drug Synergism , Eye/drug effects , Eye Proteins/metabolism , Hyperemia/chemically induced , Indomethacin/pharmacology , Injections , Iris/blood supply , Male , Miosis , Neurokinin A/pharmacology , Rabbits , Substance P/antagonists & inhibitors , Substance P/pharmacology , Vitreous Body/physiology
11.
Proc Natl Acad Sci U S A ; 95(23): 13549-54, 1998 Nov 10.
Article in English | MEDLINE | ID: mdl-9811837

ABSTRACT

The present paper describes the total chemical synthesis of the precursor molecule of the Aequorea green fluorescent protein (GFP). The molecule is made up of 238 amino acid residues in a single polypeptide chain and is nonfluorescent. To carry out the synthesis, a procedure, first described in 1981 for the synthesis of complex peptides, was used. The procedure is based on performing segment condensation reactions in solution while providing maximum protection to the segment. The effectiveness of the procedure has been demonstrated by the synthesis of various biologically active peptides and small proteins, such as human angiogenin, a 123-residue protein analogue of ribonuclease A, human midkine, a 121-residue protein, and pleiotrophin, a 136-residue protein analogue of midkine. The GFP precursor molecule was synthesized from 26 fully protected segments in solution, and the final 238-residue peptide was treated with anhydrous hydrogen fluoride to obtain the precursor molecule of GFP containing two Cys(acetamidomethyl) residues. After removal of the acetamidomethyl groups, the product was dissolved in 0.1 M Tris. HCl buffer (pH 8.0) in the presence of DTT. After several hours at room temperature, the solution began to emit a green fluorescence (lambdamax = 509 nm) under near-UV light. Both fluorescence excitation and fluorescence emission spectra were measured and were found to have the same shape and maxima as those reported for native GFP. The present results demonstrate the utility of the segment condensation procedure in synthesizing large protein molecules such as GFP. The result also provides evidence that the formation of the chromophore in GFP is not dependent on any external cofactor.


Subject(s)
Luminescent Proteins/chemistry , Protein Folding , Protein Precursors/chemistry , Protein Precursors/chemical synthesis , Amino Acid Sequence , Animals , Fluorescence , Green Fluorescent Proteins , Humans , Molecular Sequence Data , Scyphozoa
12.
Surg Today ; 28(9): 900-6, 1998.
Article in English | MEDLINE | ID: mdl-9744398

ABSTRACT

We investigated the relationship between the changes in the pulmonary blood flow and histology during acute rejection following single lung transplantation. In single lung transplantation using adult mongrel dogs, immunosuppression with cyclosporine and azathioprine was discontinued after postoperative day 14 to induce rejection. Doppler flow probes were placed adjacent to the ascending aorta and the left pulmonary artery to measure the blood flow on a daily basis. In addition, chest roentgenograms were also examined daily. The pulmonary pressure was measured using a Swan-Ganz catheter prior to and following the induction of rejection. Open lung biopsies were performed when the left pulmonary artery flow decreased to half of the prerejection value. The pulmonary artery flow decreased to 14.3% of the aortic flow 5 days after the discontinuation of immunosuppression. The graft pulmonary vascular resistance increased significantly compared to the prerejection values (P < 0.001). This was not accompanied by any abnormalities on chest roentgenography. The histology was consistent, with marked perivascular lymphocytic infiltration with little alveolar or interstitial changes. During rejection, the increased pulmonary vascular resistance in the graft was probably the result of perivascular inflammatory cell infiltration, which was seen prior to changes on chest roentgenography. Changes in the left pulmonary artery flow and histology thus appear to be closely correlated in the early stages of acute rejection.


Subject(s)
Graft Rejection/diagnosis , Lung Transplantation/physiology , Pulmonary Circulation/physiology , Animals , Biopsy , Blood Flow Velocity , Dogs , Graft Rejection/pathology , Graft Rejection/physiopathology , Lung/blood supply , Lung/pathology , Lung Transplantation/pathology , Pulmonary Artery/pathology , Pulmonary Wedge Pressure/physiology , Rheology , Vascular Resistance/physiology
13.
Int J Immunopharmacol ; 20(1-3): 111-24, 1998.
Article in English | MEDLINE | ID: mdl-9717086

ABSTRACT

We established the antigen-presenting cell line RMA-S/mCD80 expressing mouse CD80. RMA-S is an antigen processing-defective mutant originating from RMA lymphoma and can be loaded with exogenous immunogenic peptides on the major histocompatibility complex class I (MHC-I) molecules. After immunization with RMA-S or RMA-S/mCD80 loaded with B16 melanoma-derived peptides, only RMA-S/mCD80 pulsed with B16 melanoma-derived peptides showed antitumor effects against B16 melanoma in vivo. However, it showed little enhancement of survival. On the other hand, fumagillin, an inhibitor of angiogenesis, suppressed B16 melanoma growth and showed a survival promoting effect. Combination therapy with fumagillin and vaccination with B16 melanoma-derived peptides strongly inhibited tumor growth and promoted survival more than fumagillin therapy alone. These results suggest that vaccination with poorly immunogenic tumor-derived peptides combined with antitumor drugs, such as anti-angiogenic compounds, may be useful.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antigens, Neoplasm/immunology , B7-1 Antigen/immunology , Cancer Vaccines/pharmacology , Fatty Acids, Unsaturated/pharmacology , Melanoma, Experimental/therapy , Animals , Antigen-Presenting Cells/metabolism , Antigens, Neoplasm/biosynthesis , B7-1 Antigen/biosynthesis , Combined Modality Therapy , Cyclohexanes , Female , Melanoma, Experimental/blood supply , Melanoma, Experimental/immunology , Mice , Mice, Inbred C57BL , Neoplasm Transplantation , Neovascularization, Pathologic/drug therapy , Sesquiterpenes
14.
Biosci Biotechnol Biochem ; 62(5): 986-9, 1998 May.
Article in English | MEDLINE | ID: mdl-9648231

ABSTRACT

Cytosolic free calcium ion concentration ([Ca2+]cyt) after a salicylic acid (SA)-stimulus was monitored in cells of the yeast Saccharomyces cerevisiae expressing apoaequorin, which constitutes a Ca(2+)-sensitive luminescent protein, aequorin, when combined with coelenterazine. SA induced a transient [Ca2+]cyt elevation that was dependent on the concentration of SA and pH of the SA solution. The SA-induced [Ca2+]cyt elevation was not reduced in Ca(2+)-deficient medium, suggesting that Ca2+ was mobilized from an intracellular Ca2+ store(s). Benzoic acid, butyric acid and sorbic acid did not induced a [Ca2+]cyt elevation.


Subject(s)
Aequorin/metabolism , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Calcium/metabolism , Cytosol/drug effects , Plant Growth Regulators/pharmacology , Saccharomyces cerevisiae/drug effects , Salicylates/pharmacology , Cytosol/metabolism , Luminescent Measurements , Saccharomyces cerevisiae/metabolism , Salicylic Acid
15.
Eur J Pharmacol ; 346(1): 81-5, 1998 Apr 03.
Article in English | MEDLINE | ID: mdl-9617756

ABSTRACT

We investigated the effects of S-(4-dimethylaminobenzyl)-N-[(2S)-3-mercapto-2-methylpropionyl]-L- cysteine (SA6541), a potent leukotriene A4 hydrolase inhibitor. on early phase of carrageenan-induced dermatitis model. Carrageenan injection induced edema and neutrophil influx in the mouse ear. SA6541 inhibited edema formation and neutrophil influx. SA6541 also inhibited leukotriene B4 production but not prostaglandin E2 production in the mouse ear. On the other hand, indomethacin inhibited edema formation but not neutrophil influx. Indomethacin also inhibited prostaglandin E2 production but not leukotriene B4 production. Combination therapy with SA6541 and indomethacin strongly inhibited edema formation in comparison with treatment with either agent alone. These results suggest that leukotriene B4 may be important in the pathogenesis of dermatitis.


Subject(s)
Aniline Compounds/pharmacology , Carrageenan/toxicity , Cysteine/analogs & derivatives , Dermatitis, Contact/prevention & control , Enzyme Inhibitors/pharmacology , Epoxide Hydrolases/antagonists & inhibitors , Indomethacin/pharmacology , Animals , Cysteine/pharmacology , Dermatitis, Contact/metabolism , Edema/prevention & control , Leukotriene B4/antagonists & inhibitors , Leukotriene B4/biosynthesis , Male , Mice , Mice, Inbred ICR
16.
Curr Eye Res ; 17(5): 501-5, 1998 May.
Article in English | MEDLINE | ID: mdl-9617545

ABSTRACT

PURPOSE: We investigated the role of platelet-activating factor (PAF) in cell infiltration in endotoxin-induced uveitis (EIU) in guinea pigs. METHODS: To elicit EIU, lipopolysaccharide (LPS) was injected into the anterior chamber of the eye. Cell numbers in the aqueous humor after LPS injection were determined by flow cytometry. PAF and prostaglandin E2 (PGE2) production after LPS injection were also examined. RESULTS: Intracameral injection of LPS induced cell infiltration into the anterior chamber, and platelet-activating factor (PAF) was detected in the aqueous humor. In addition, topical apafant (PAF antagonist) partially inhibited cell infiltration. Intracameral injection of PAF scarcely induced cell infiltration but the reaction with EIU was accelerated by intracameral injection of a small amount of PAF. CONCLUSIONS: These results suggest that PAF has weak direct activity on cell infiltration in intraocular inflammation but enhances intraocular inflammation.


Subject(s)
Chemotaxis, Leukocyte/physiology , Escherichia coli , Leukocytes/physiology , Lipopolysaccharides/toxicity , Platelet Activating Factor/physiology , Uveitis, Anterior/metabolism , Animals , Anterior Chamber/cytology , Anterior Chamber/drug effects , Anterior Chamber/metabolism , Aqueous Humor/metabolism , Azepines/pharmacology , Betamethasone/analogs & derivatives , Betamethasone/pharmacology , Dinoprostone/metabolism , Flow Cytometry , Guinea Pigs , Indomethacin/pharmacology , Leukocyte Count , Male , Ophthalmic Solutions , Platelet Activating Factor/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Triazoles/pharmacology , Uveitis, Anterior/chemically induced , Uveitis, Anterior/pathology
17.
Xenobiotica ; 28(1): 53-62, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9493319

ABSTRACT

1. We report differences in the pharmacokinetics of (4R)-hexahydro-7,7-dimethyl-6-oxo-1,2,5-(3-14C)dithiazocine-4-carb oxylic acid (14C-SA3443) between the normal fasting and non-fasting rat, especially in the blood concentration-time curves and respiratory excretion. Exhalation of 14CO2 was an important route of elimination and accounted for 21.2% of the dose in the non-fasting rat but only 3.7% in fasting animals. 2. In the intestinal microorganism-compromised rat, we found little differences in the pharmacokinetics of 14C-SA3443 between fasting and non-fasting states. No respiratory excretion was observed in the intestinal microorganism-compromised animal. 3. In the reaction mixture of 14C-SA3443 with the cecal contents of rat, 14C-acetic acid and 14C-butyric acid were detected and 14CO2 barely detected. 4. The amounts of 14C-acetic acid and 14C-butyric acid in the reaction mixture of 14C-SA3443 with non-fasting rat cecal contents were more than those with fasting rat cecal contents. 5. We concluded that the reason for the different pharmacokinetics of 14C-SA3443 between the fasting and non-fasting rat was the differences in participation of the metabolism of 14C-SA3443 by intestinal microorganisms.


Subject(s)
Adjuvants, Immunologic/pharmacokinetics , Azocines/pharmacokinetics , Disulfides/pharmacokinetics , Intestines/microbiology , Adjuvants, Immunologic/administration & dosage , Administration, Oral , Animals , Anti-Bacterial Agents/pharmacology , Azocines/administration & dosage , Carbon Radioisotopes , Cecum/drug effects , Cecum/metabolism , Cecum/microbiology , Chromatography, High Pressure Liquid , Disulfides/administration & dosage , Fasting , Feces , Intestinal Mucosa/metabolism , Intestines/drug effects , Male , Rats , Rats, Wistar
18.
Biochem Pharmacol ; 55(3): 297-304, 1998 Feb 01.
Article in English | MEDLINE | ID: mdl-9484795

ABSTRACT

Leukotriene B4 (LTB4) is a product of the 5-lipoxygenase pathway of arachidonic acid (AA) metabolism. LTB4 is a potent chemotactic factor for neutrophils and has been postulated to play an important role in a variety of pathological conditions including rheumatoid arthritis, psoriasis, and inflammatory bowel disease. To investigate the role of LTB4 in dermatitis, we used S-(4-dimethylaminobenzyl)-N-[(2S)-3-mercapto-2-methylpropionyl]-L- cysteine (SA6541), a potent leukotriene A4 (LTA4) hydrolase inhibitor. SA6541 inhibited LTB4 production with an IC50 value of 270 nM in vitro. 5-Hydroperoxyeicosatetraenoic acid (5-HPETE) or AA injection induced LTB4 production and neutrophil influx in mouse ear. SA6541 inhibited 5-HPETE- and AA-induced LTB4 production and neutrophil influx in mouse ear when administered orally at a dose of 50 mg/kg. SA6541 also inhibited 5-HPETE-induced prostaglandin E2 (PGE2) production, probably by an indirect effect through the inhibition of LTB4 production. These results suggest that LTB4 may be important in the pathogenesis of dermatitides such as psoriasis.


Subject(s)
Dermatitis/metabolism , Leukotriene B4/metabolism , Aniline Compounds/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Arachidonic Acid/adverse effects , Cysteine/analogs & derivatives , Cysteine/pharmacology , Dermatitis/etiology , Enzyme Inhibitors/pharmacology , Epoxide Hydrolases/antagonists & inhibitors , Leukotriene B4/biosynthesis , Leukotrienes/adverse effects , Male , Mice , Mice, Inbred ICR
19.
Biochem Biophys Res Commun ; 242(3): 659-62, 1998 Jan 26.
Article in English | MEDLINE | ID: mdl-9464273

ABSTRACT

In order to trace the in vivo dynamics of cancer cells, we introduced jellyfish aequorin cDNA into metastatic (A-11) and nonmetastatic (3LL) Lewis lung cancer cell lines. The transformants (e.g., A-11-4 and 3LL-24) remained highly tumorigenic when they were s.c. injected into C57BL/6 mice and the A-11-4 clone produced metastatic tumors in the lung. Luminescence produced by the expressed aequorin was detectable in these transformants in culture as well as in cells of primary or secondary tumors. The limit of detection of the aequorin assay was approximately 90 cells, whereas approximately 5 x 10(4) cells could be macroscopically seen as metastatic foci in the lung. Thus, the aequorin assay is approximately 500-fold more sensitive than macroscopic examination in detecting cancer metastasis.


Subject(s)
Aequorin/genetics , Neoplasms, Experimental/metabolism , Animals , Cell Count , Cell Division , Cell Survival , Gene Expression Regulation, Neoplastic/genetics , Luminescent Measurements , Lung Neoplasms/metabolism , Mice , Mice, Inbred Strains , Transformation, Genetic , Tumor Cells, Cultured
20.
Inflamm Res ; 46(6): 193-8, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9243301

ABSTRACT

OBJECTIVE AND DESIGN: We investigated the anti-inflammatory effects of 16 beta-methyl-17 alpha,21-diesterified glucocorticoids which are well known as potent topical glucocorticoids in man on endotoxin-induced uveitis (EIU) in rats. MATERIAL: Female Lewis rats were used. TREATMENT: Glucocorticoids were instilled (0.01%-1.0%) or subcutaneously injected (0.1-10 mg/kg) to rats. METHODS: To elicit EIU, LPS (500 micrograms/kg) was injected into the footpad of rats. Twelve hours after LPS injection, cell number in aqueous humor was counted by flow cytometry. Endotoxin-induced in vivo tumor necrosis factor-alpha (TNF-alpha) production was also examined. RESULTS: 16 beta-methyl-17 alpha,21-diesterified glucocorticoids showed no effects or some enhancement of cell infiltration into the aqueous humor in EIU by topical instillation. Systemic injection of these glucocorticoids showed only weak inhibition of cell infiltration and TNF-alpha production. On the other hand, betamethasone phosphate strongly inhibited the cell infiltration and TNF-alpha production. Combined systemic injection of 16 beta-methyl-17 alpha,21-diesterified glucocorticoids and betamethasone phosphate reduced the inhibitory effects of the latter. CONCLUSIONS: These results suggest that 16 beta-methyl-17 alpha,21-diesterified glucocorticoids might act as partial agonists of glucocorticoid in rats.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Glucocorticoids/pharmacology , Uveitis/drug therapy , Administration, Topical , Animals , Betamethasone/pharmacology , Female , Lipopolysaccharides/toxicity , Rats , Rats, Inbred Lew , Tumor Necrosis Factor-alpha/biosynthesis
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