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1.
Dis Esophagus ; 30(7): 1-7, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-30052898

ABSTRACT

Esophageal squamous cell carcinoma is a highly aggressive neoplasm and the sixth leading cause of global cancer-related death; the 5-year survival rate for esophageal cancer is only about 20%-25% for all stages. Therefore, improving the therapeutic effect is important. This study assessed whether low-dose hyperthermia (LDH) enhances the antitumor effects of chemotherapy. The antitumor effect of chemotherapy with/without LDH in the squamous cell carcinoma cell line SCCVII was evaluated. A comprehensive analysis was performed with real-time polymerase chain reaction (PCR) to study the hyperthermia-induced changes in the gene expression of SCCVII cell lines. In addition, the cytotoxic and apoptotic changes in the cells treated with LDH combined with/without 5-fluorouracil (5-FU) were measured. LDH combined with 5-FU (10 nM) strongly inhibited the cell growth of SCCVII, with flow cytometry showing an increased population of apoptotic cells. PCR showed that LDH promoted a 25.22-fold increase of p53 mRNA and 18.08-fold increase of Bax mRNA in vitro. MDR1 expression was decreased to 28.7% after LDH. This treatment can result in much higher efficacy of antitumor drugs. After LDH, the expressions of TS decreased to 12.06%, OPRT increased by 4.17-fold, and DPD did not change (1.03-fold). This transformations will induce susceptibility to 5-FU. LDH may be a useful enhancer of chemotherapy drugs for squamous cell carcinoma.


Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Carcinoma, Squamous Cell/therapy , Esophageal Neoplasms/therapy , Fluorouracil/pharmacology , Gene Expression , Hyperthermia, Induced , ATP Binding Cassette Transporter, Subfamily B/genetics , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Combined Modality Therapy , Dihydrouracil Dehydrogenase (NADP)/genetics , Gene Expression/drug effects , Humans , Orotate Phosphoribosyltransferase/genetics , RNA, Messenger/metabolism , Thymidylate Synthase/genetics , Tumor Suppressor Protein p53/genetics , bcl-2-Associated X Protein/genetics
2.
Br J Cancer ; 110(1): 189-98, 2014 Jan 07.
Article in English | MEDLINE | ID: mdl-24196787

ABSTRACT

BACKGROUND: FSCN1 and matrix metalloproteinase 14 (MMP14) are both invadopodia-related proteins. We herein elucidate the tumourigenicity of these proteins and identify novel therapeutic agents in esophageal squamous cell carcinoma (ESCC). METHODS: FSCN1 and MMP14 were evaluated by immunohistochemistry and quantitative PCR, and microRNA (miR)-133a was also evaluated by PCR in surgical ESCC specimens. The roles of FSCN1, MMP14 and miR-133a were established in ESCC cells. RESULTS: The expression of FSCN1 or MMP14 was an independent poor prognostic factor according to a multivariate analysis of immunohistochemistry, and their co-expression correlated with the poorest overall survival (OS) out of all the examined factors. Additionally, their mRNAs significantly correlated and both inversely correlated with miR-133a in surgical specimens. Transfection of a miR-133a mimic decreased the mRNA and protein levels of both FSCN1 and MMP14 in ESCC cells. The knockdown of FSCN1 or MMP14 and transfection of a miR-133a mimic inhibited the proliferation and invasion of ESCC cells. Patients with a lower miR-133a expression have a significantly poorer OS than those with a higher expression. CONCLUSION: The combined expression of FSCN1 and MMP14 is associated with a poor prognosis, and miR-133a, which regulates their mRNAs, can serve as a strong tumour suppressor of ESCC.


Subject(s)
Carrier Proteins/genetics , Cell Surface Extensions/genetics , Esophageal Neoplasms/genetics , Matrix Metalloproteinase 14/genetics , MicroRNAs/genetics , Microfilament Proteins/genetics , Carrier Proteins/biosynthesis , Cell Line, Tumor , Cell Surface Extensions/metabolism , Cell Surface Extensions/pathology , Esophageal Neoplasms/metabolism , Esophageal Neoplasms/pathology , Humans , Matrix Metalloproteinase 14/biosynthesis , Microfilament Proteins/biosynthesis , Proportional Hazards Models , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/genetics , Transfection
3.
Br J Cancer ; 108(3): 644-52, 2013 Feb 19.
Article in English | MEDLINE | ID: mdl-23361059

ABSTRACT

BACKGROUND: Recent studies have demonstrated that microRNAs (miRNAs) are stably detectable in blood and can serve as useful biomarkers for cancer. METHODS: We performed an miRNA array using serum samples obtained from oesophageal squamous cell carcinoma (ESCC) patients or healthy controls. MiR-1246 was the most markedly elevated in ESCC patients. Therefore, miR-1246 was selected as a candidate for further analysis. The serum miR-1246 level in 46 healthy controls and 101 ESCC patients was evaluated and compared among various clinicopathological characteristics. MiR-1246 expressions in tissue, exosomal, and cellular samples were also examined. RESULTS: Serum miR-1246 alone yielded an receiver-operating characteristic curve area of 0.754, with 71.3% sensitivity and 73.9% specificity for distinguishing ESCC patients from healthy controls. Serum miR-1246 was significantly correlated with the TNM stage and showed to be the strongest independent risk factor for poor survival (HR, 4.032; P=0.017). Unlike the tendency shown in previous reports, miR-1246 was not upregulated in ESCC tissue samples. Furthermore, exosomal miR-1246 did not reflect the abundance in the cell of origin. CONCLUSION: These data support our contention that serum miR-1246 has strong potential as a novel diagnostic and prognostic biomarker in ESCC, and its releasing mechanism is selective and independent of tissue miRNA abundance.


Subject(s)
Adenocarcinoma/genetics , Biomarkers, Tumor/blood , Esophageal Neoplasms/genetics , Esophagus/metabolism , Gene Expression Profiling , MicroRNAs/blood , Adenocarcinoma/blood , Adenocarcinoma/pathology , Aged , Biomarkers, Tumor/genetics , Case-Control Studies , Esophageal Neoplasms/blood , Esophageal Neoplasms/pathology , Exosomes/metabolism , Female , Humans , Lymphatic Metastasis , Male , MicroRNAs/genetics , Neoplasm Metastasis , Neoplasm Staging , Oligonucleotide Array Sequence Analysis , Prognosis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction
4.
J Vet Intern Med ; 23(6): 1164-9, 2009.
Article in English | MEDLINE | ID: mdl-19909427

ABSTRACT

BACKGROUND: Intravenous administration of human immunoglobulin G (hIVIgG) has been suggested to potentiate thromboembolism in dogs, but supportive scientific reports are lacking. OBJECTIVES: To determine if hIVIgG therapy promotes hypercoagulability and inflammation in dogs. ANIMALS: Twelve healthy Beagle dogs. METHODS: Prospective, experimental trial. An hIVIgG/saline solution was infused IV at 1 g/kg BW over 8 hours to 6 dogs, and physiological saline was infused to the other 6 dogs. Blood samples were drawn before, during, and after infusion for serial measurement of indicators of coagulation and inflammation. Data were analyzed by 2-way repeated measures analysis of variance. RESULTS: Dogs administered hIVIgG developed mildly decreased blood platelet concentrations without thrombocytopenia (median, 200 x 10(3)/microL; range, 150-302 x 10(3)/microL; P < .01), leukopenia (median, 3.5 x 10(3)/microL; range, 20-62 x 10(3)/microL; P < .001), and mildly increased plasma total protein concentrations (median, 6.3 g/dL; range, 5.6-6.7 g/dL; P < .001). Administration of hIVIgG was also associated with increases in fibrin/fibrinogen degradation products in all dogs (either 5 microg/mL or 10 microg/dL), thrombin-antithrombin III complexes (median, 7.2 ng/mL; range, 4.9-14.2 ng/mL; P < .001), and C-reactive protein concentrations (median, 2.5 mg/dL; range, 0.5-4.3 mg/dL; P < .01). CONCLUSION AND CLINICAL IMPORTANCE: Administration of hIVIgG to dogs promotes hypercoagulability and an inflammatory state. This should be further evaluated and considered when using hIVIgG in dogs with IMHA or other prothrombotic conditions.


Subject(s)
Dog Diseases/chemically induced , Immunoglobulin G/administration & dosage , Immunoglobulin G/adverse effects , Inflammation/veterinary , Thrombosis/veterinary , Animals , Blood Proteins , Dogs , Female , Humans , Inflammation/chemically induced , Injections, Intravenous , Male , Platelet Count/veterinary , Thrombosis/chemically induced
6.
Biotechnol Lett ; 25(1): 23-8, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12882301

ABSTRACT

Microorganisms isolated from soil samples were screened for their ability to degrade various biodegradable polyester-based plastics. The most active strain, designated as strain TB-13, was selected as the best strain for degrading these plastics. From its phenotypic and genetic characteristics, strain TB-13 was closely related to Paenibacillus amyloyticus. It could degrade poly(lactic acid), poly(butylene succinate), poly(butylene succinate-co-adipate), poly(caprolactone) and poly(ethylene succinate) but not poly(hydroxybutylate-co-valerate). However, it could not utilize these plastics as sole carbon sources. Both protease and esterase activities, which may be involved in the degradation of plastic, were constitutively detected in the culture broth.


Subject(s)
Bacteria, Aerobic/isolation & purification , Bacteria, Aerobic/metabolism , Plastics/metabolism , Polyesters/metabolism , Soil Microbiology , Adipates/metabolism , Bacteria, Aerobic/classification , Bacteria, Aerobic/physiology , Biodegradation, Environmental , Endopeptidases/metabolism , Esterases/metabolism , Lactic Acid/metabolism , Polymers/metabolism , Species Specificity , Succinates/metabolism
8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(1 Pt 2): 016705, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11461440

ABSTRACT

We present a new algorithm to calculate the thermodynamic quantities of three-dimensional (3D) classical statistical systems, based on the ideas of the tensor product state and the density matrix renormalization group. We represent the maximum-eigenvalue eigenstate of the transfer matrix as the product of local tensors that are iteratively optimized by the use of the "vertical density matrix" formed by cutting the system along the transfer direction. This algorithm, which we call vertical density matrix algorithm (VDMA), is successfully applied to the 3D Ising model. Using the Suzuki-Trotter transformation, we can also apply the VDMA to 2D quantum systems, which we demonstrate for the 2D transverse field Ising model.

9.
Int J Cancer ; 91(4): 523-8, 2001 Feb 15.
Article in English | MEDLINE | ID: mdl-11251976

ABSTRACT

A unique lymphocyte lineage, the Valpha14 NKT cells, expresses both NK1.1 and an invariant antigen receptor encoded by Valpha14 and Jalpha281 gene segments. Valpha14 NKT cells play crucial roles in various immune responses, including autoimmune diseases, allergic reactions and anti-tumor immunity. Valpha14 NKT cells were demonstrated to be essential for anti-tumor effect of IL-12 in vivo. Here, we report that adoptive transfer of IL-12-activated Valpha14 NKT cells prevents hepatic metastasis of B16 melanoma. The injection of large amounts of IL-2, IL-4, and IFN-gamma, which are cytokines produced by activated Valpha14 NKT cells, exhibited no significant inhibition of the metastasis of this melanoma. The cells prepared from the liver of IL-12-injected mice expressed a potent cytotoxic activity on B16 melanoma cells in vitro. Although the adoptive transfer of IL-12-activated Valpha14 NKT cells prevents hepatic metastasis of B16 melanoma, activated NK cells from IL-12-injected RAG-1-/- mice failed to inhibit the metastasis of this melanoma. Thus, the anti-tumor effect of IL-12 can be replaced by adoptive transfer of IL-12-activated Valpha14 NKT cells but not by IL-12-activated NK cells, suggesting a minor role of NK cells for the IL-12-mediated anti-tumor effect in this experimental system. Moreover, our studies have suggested the involvement of direct cytotoxic mechanisms rather than cytokine-mediated immune responses at the effector phase of the Valpha14 NKT cell-mediated anti-tumor activity.


Subject(s)
Interleukin-12/metabolism , Lymphocytes/cytology , Lymphocytes/metabolism , Melanoma, Experimental/drug therapy , Neoplasms/drug therapy , Adoptive Transfer , Animals , Cell Line , Chromium Radioisotopes/metabolism , Enzyme-Linked Immunosorbent Assay , Interferon-gamma/biosynthesis , Interferon-gamma/pharmacology , Interleukin-12/pharmacology , Interleukin-2/biosynthesis , Interleukin-2/pharmacology , Interleukin-4/biosynthesis , Interleukin-4/pharmacology , Killer Cells, Natural/metabolism , Liver/cytology , Liver Neoplasms/pathology , Liver Neoplasms/prevention & control , Liver Neoplasms/secondary , Melanoma, Experimental/pathology , Mice , Mice, Transgenic , Neoplasm Metastasis , Neoplasm Transplantation , Recombinant Proteins/metabolism , Spleen/cytology , Time Factors
11.
FEMS Microbiol Lett ; 189(1): 25-9, 2000 Aug 01.
Article in English | MEDLINE | ID: mdl-10913861

ABSTRACT

Various microorganisms were screened for their ability to degrade poly(tetramethylene succinate)-co-(tetramethylene adipate) (PBSA). Strain BS-3, which was newly isolated from a soil sample, was selected as the best strain. From taxonomical studies, the strain was tentatively ascribed to belong to the genus Acidovorax, most probably to the species A. delafieldii. Strain BS-3 could degrade both solid and emulsified PBSA, and also emulsified poly(tetramethylene succinate). During the degradation, a lipase activity was observed in the culture broth. This lipase activity was induced more strongly by PBSA than by tributyrin or triolein which are typical substrates of lipase. These observations strongly suggest that this lipase was involved in the PBSA biodegradation in strain BS-3.


Subject(s)
Gram-Negative Aerobic Rods and Cocci/classification , Gram-Negative Aerobic Rods and Cocci/metabolism , Plastics/metabolism , Polyesters/metabolism , Soil Microbiology , Adipates/chemistry , Biodegradation, Environmental , Culture Media , Detergents/pharmacology , Lipase/metabolism , Polyesters/chemistry , Substrate Specificity
12.
Clin Cardiol ; 23(5): 359-64, 2000 May.
Article in English | MEDLINE | ID: mdl-10803445

ABSTRACT

BACKGROUND: We have previously shown that QT-interval changes are more useful than ST-T changes in evaluating the severity of exercise-induced myocardial ischemia in patients with right bundle-branch block (RBBB). HYPOTHESIS: The purpose of this study was to evaluate whether the improvement in regional myocardial blood flow (RMBF) in ischemic areas and cardiac output after percutaneous transluminal coronary angioplasty (PTCA) can be predicted by exercise-induced QT-interval changes prior to PTCA. METHODS: The RMBF and cardiac output were quantified with nitrogen-13 ammonia positron emission tomography at rest and during exercise in 20 patients with RBBB and ischemic heart disease before and 6 months after PTCA, and in 9 healthy volunteers. RESULTS: Before PTCA, exercise-induced prolongation by < 20 ms or shortening of the Bazett-corrected QT (QTc) interval (454 +/- 38 to 451 +/- 41 ms, p = NS) was observed in 13 patients (Group 1) and prolongation by > or = 20 ms (429 +/- 44 to 466 +/- 50 ms, p < 0.002) was observed in 7 (Group 2). The number of regions of exercise-induced ischemia was significantly greater in Group 2 than in Group 1 (4.0 +/- 1.2 vs. 2.1 +/- 1.2, p < 0.01). The RMBF in regions of exercise-induced ischemia and cardiac output at rest was not significantly different between Groups 1 and 2, whereas during exercise both the parameters were significantly lower in Group 2 than in Group 1 (both p < 0.05). After successful PTCA, RMBF both at rest and during exercise improved significantly in Group 1 (0.67 +/- 0.04 to 0.71 +/- 0.06 ml/min/g, 0.74 +/- 0.05 to 0.84 +/- 0.08 ml/min/g; both p < 0.0001), but did not improve significantly in Group 2 (0.63 +/- 0.05 to 0.65 +/- 0.07 ml/min/g, 0.65 +/- 0.04 to 0.69 +/- 0.11 ml/ min/g; both p = NS). Cardiac output during exercise improved significantly in Group 1 (6.4 +/- 0.7 to 7.4 +/- 0.9 l/min; p < 0.002) but not in Group 2 (5.7 +/- 0.6 to 5.9 +/- 0.6 l/min; p = NS). CONCLUSIONS: Our results suggest that the marked prolongation of the QTc interval induced by pre-PTCA exercise may predict a lack of improvement in RMBF in ischemic areas and cardiac output after PTCA in patients with RBBB and ischemic heart disease.


Subject(s)
Angioplasty, Balloon, Coronary , Bundle-Branch Block/diagnosis , Coronary Circulation/physiology , Electrocardiography , Myocardial Ischemia/diagnostic imaging , Myocardial Ischemia/therapy , Adult , Aged , Analysis of Variance , Cardiac Output/physiology , Coronary Angiography , Exercise Test , Female , Humans , Male , Middle Aged , Myocardial Ischemia/diagnosis , Predictive Value of Tests , Prognosis , Regional Blood Flow , Statistics, Nonparametric , Tomography, Emission-Computed
13.
Chemosphere ; 40(12): 1365-71, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10789976

ABSTRACT

The concentration distributions of NOx, PM, HC and CO in an urban street canyon have been estimated using a two-dimensional air quality numerical model based on the k-epsilon turbulent model and the atmospheric convection diffusion equation when various cetane improvers were used in diesel fuels. A wind vortex can be found within the street canyon, and the pollutants emitted from the bottom of the street canyon tend to follow the course of the wind field, moving circularly. The addition of cetane improvers can improve the air quality in a street canyon, all of the pollutants were found to decrease with increasing centane number.


Subject(s)
Air Pollutants/analysis , Confined Spaces , Vehicle Emissions/analysis , Air/analysis , Carbon Monoxide/analysis , Cities , Gasoline/adverse effects , Gasoline/analysis , Gasoline/standards , Hydrocarbons/analysis , Models, Theoretical , Nitric Oxide/analysis , Wind
14.
Acta Cardiol ; 55(1): 25-31, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10707755

ABSTRACT

OBJECTIVE: ST-segment depression is believed as a common electrocardiographic sign of myocardial ischemia during exercise testing. Ischemia is generally defined as oxygen deprivation due to reduced perfusion. However, the exact relationship of the ischemic definition to ST-segment depression remains unclear. This study was conducted to evaluate the correlation between myocardial oxygen demand and myocardial blood flow (MBF) when ischemic (horizontal or downsloping) ST-segment depression of > or = 0.1 mV 80 ms after the J point developed during low-level exercise. METHODS AND RESULTS: Seventy-two patients with angiographically proven coronary artery disease (CAD) and 9 healthy volunteers underwent exercise positron emission tomography (PET). Myocardial oxygen demand was defined as a rate-pressure product (RPP, heart rate x systolic blood pressure) during exercise and MBF was quantified by nitrogen-13 ammonia perfusion PET. The myocardial demand-supply balance (MDSB) index was calculated from the MBF ratio (values during exercise/values at rest) against the RPP ratio (values during exercise/values at rest). The MDSB index was significantly lower in patients with ischemic ST-segment depression than in patients with non-ischemic ST depression and healthy volunteers (0.82 +/- 0.16 vs. 1.02 +/- 0.17, p < 0.0001 and vs. 0.99 +/- 0.14, p = 0.0109). Further, the presence of inadequate increase in MBF of < or = 10% (2 SD below the mean % value of healthy volunteers) during exercise in regional myocardium perfused by stenotic CAD significantly correlated with exercise-induced ischemic ST-segment depression (p = 0.0105). CONCLUSIONS: Our study could demonstrate that exercise-induced ischemic ST-segment depression is associated with myocardial ischemia due to exercise-induced imbalance between myocardial oxygen demand and global and regional MBF supply in patients with proven CAD.


Subject(s)
Coronary Circulation/physiology , Electrocardiography , Exercise/physiology , Myocardium/metabolism , Oxygen Consumption/physiology , Adult , Aged , Angina Pectoris/diagnosis , Angina Pectoris/physiopathology , Coronary Angiography/methods , Coronary Angiography/statistics & numerical data , Coronary Disease/diagnosis , Coronary Disease/physiopathology , Exercise Test/methods , Exercise Test/statistics & numerical data , Female , Humans , Male , Middle Aged , Myocardial Ischemia/diagnosis , Myocardial Ischemia/physiopathology , Reference Values , Tomography, Emission-Computed/methods , Tomography, Emission-Computed/statistics & numerical data
15.
Proc Natl Acad Sci U S A ; 97(2): 740-4, 2000 Jan 18.
Article in English | MEDLINE | ID: mdl-10639149

ABSTRACT

The immunological mechanisms that regulate abortion are largely unknown. Here, we found that a distinct subset of lymphocytes, Valpha14 NKT cells expressing an invariant antigen receptor encoded by Valpha14/Jalpha281 and Vbeta7 segments, accumulated in the decidua during pregnancy and provoked abortion upon stimulation with alpha-galactosylceramide (alpha-GalCer), a specific ligand for Valpha14 NKT cells. The alpha-GalCer-mediated abortion was not observed in Valpha14 NKT-, IFN-gamma-, tumor necrosis factor alpha-, or perforin-knock-out mice and appeared to be due to the degeneration of embryonic trophoblasts mediated by the activated Valpha14 NKT cells whose perforin-dependent killing and production of IFN-gamma and tumor necrosis factor alpha were essential. The possible role of the decidual Valpha14 NKT cells in the pathogenesis of abortion is discussed.


Subject(s)
Abortion, Induced , Decidua/cytology , Killer Cells, Natural/immunology , Receptors, Antigen, T-Cell, alpha-beta/metabolism , Animals , Cytokines/metabolism , Female , Flow Cytometry , Galactosylceramides/adverse effects , Interferon-gamma/metabolism , Killer Cells, Natural/cytology , Killer Cells, Natural/metabolism , Male , Membrane Glycoproteins/physiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Perforin , Pore Forming Cytotoxic Proteins , Pregnancy , Specific Pathogen-Free Organisms , Trophoblasts/drug effects , Trophoblasts/pathology , Tumor Necrosis Factor-alpha/metabolism
16.
Cancer Res ; 59(20): 5102-5, 1999 Oct 15.
Article in English | MEDLINE | ID: mdl-10537282

ABSTRACT

Human V alpha24 NKT cells bearing an invariant V alpha24J alphaQ antigen receptor, the counterpart of the murine V alpha14 NKT cells, are activated by the specific ligand, alpha-galactosylceramide (alpha-GalCer) in a CD1d-dependent manner. Here, we demonstrate that the alpha-GalCer-activated V alpha24 NKT cells exert a potent perforin-dependent cytotoxic activity against a wide variety of human tumor cell lines. In addition, we demonstrate that V alpha24 NKT cells and dendritic cells (DCs) from melanoma patients are functionally normal, even in the tumor-bearing status. The potential use of alpha-GalCer-activated V alpha24 NKT cells and/or DCs from patients for cancer immunotherapy is discussed.


Subject(s)
Cytotoxicity, Immunologic , Glycolipids/pharmacology , Killer Cells, Natural/immunology , Adult , Aged , Animals , Antigen Presentation , Dendritic Cells/physiology , Female , Humans , Major Histocompatibility Complex , Male , Melanoma/immunology , Mice , Mice, Inbred BALB C
17.
J Immunol ; 163(5): 2387-91, 1999 Sep 01.
Article in English | MEDLINE | ID: mdl-10452972

ABSTRACT

A unique lymphoid lineage, Valpha14 NKT cells, bearing an invariant Ag receptor encoded by Valpha14 and Jalpha281 gene segments, play crucial roles in various immune responses, including protective immunity against malignant tumors. A specific ligand of Valpha14 NKT cells is determined to be alpha-galactosylceramide (alpha-GalCer) which is presented by the CD1d molecule. Here, we report that dendritic cells (DCs) pulsed with alpha-GalCer effectively induce potent antitumor cytotoxic activity by specific activation of Valpha14 NKT cells, resulting in the inhibition of tumor metastasis in vivo. Moreover, a complete inhibition of B16 melanoma metastasis in the liver was observed when alpha-GalCer-pulsed DCs were injected even 7 days after transfer of tumor cells to syngeneic mice where small but multiple metastatic nodules were already formed. The potential utility of DCs pulsed with alpha-GalCer for tumor immunotherapy is discussed.


Subject(s)
Dendritic Cells/transplantation , Galactosylceramides/immunology , Immunotherapy, Adoptive/methods , Melanoma, Experimental/prevention & control , Melanoma, Experimental/secondary , Animals , Cytotoxicity Tests, Immunologic , Dendritic Cells/immunology , Galactosylceramides/administration & dosage , Injections, Intravenous , Killer Cells, Natural/immunology , Liver Neoplasms/immunology , Liver Neoplasms/pathology , Liver Neoplasms/prevention & control , Liver Neoplasms/secondary , Lung Neoplasms/immunology , Lung Neoplasms/prevention & control , Lung Neoplasms/secondary , Lymphocyte Activation/immunology , Melanoma, Experimental/immunology , Melanoma, Experimental/pathology , Mice , Mice, Inbred C57BL , Mice, Transgenic , T-Lymphocyte Subsets/immunology
18.
Appl Microbiol Biotechnol ; 51(2): 134-40, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10091317

ABSTRACT

Polyurethane (PUR) is a polymer derived from the condensation of polyisocyanate and polyol and it is widely used as a base material in various industries. PUR, in particular, polyester PUR, is known to be vulnerable to microbial attack. Recently, environmental pollution by plastic wastes has become a serious issue and polyester PUR had attracted attention because of its biodegradability. There are many reports on the degradation of polyester PUR by microorganisms, especially by fungi. Microbial degradation of polyester PUR is thought to be mainly due to the hydrolysis of ester bonds by esterases. Recently, polyester-PUR-degrading enzymes have been purified and their characteristics reported. Among them, a solid-polyester-PUR-degrading enzyme (PUR esterase) derived from Comamonas acidovorans TB-35 had unique characteristics. This enzyme has a hydrophobic PUR-surface-binding domain and a catalytic domain, and the surface-binding domain was considered as being essential for PUR degradation. This hydrophobic surface-binding domain is also observed in other solid-polyester-degrading enzymes such as poly(hydroxyalkanoate) (PHA) depolymerases. There was no significant homology between the amino acid sequence of PUR esterase and that of PHA depolymerases, except in the hydrophobic surface-binding region. Thus, PUR esterase and PHA depolymerase are probably different in terms of their evolutionary origin and it is possible that PUR esterases come to be classified as a new solid-polyester-degrading enzyme family.


Subject(s)
Bacteria/metabolism , Fungi/metabolism , Polyesters/metabolism , Polyurethanes/metabolism , Bacteria/genetics , Biodegradation, Environmental , Polyesters/chemistry , Polyurethanes/chemistry
19.
Article in English | MEDLINE | ID: mdl-11969725

ABSTRACT

We study the asymptotic behavior of the eigenvalue distribution of the corner transfer matrix (M(CTM)) and the density matrix (M(DM)) in the density-matrix renormalization group. We utilize the relationship M(DM)=M(4)(CTM), which holds for noncritical systems in the thermodynamic limit. We derive the exact and universal asymptotic form of the M(DM) eigenvalue distribution for a class of integrable models in the massive regime. For nonintegrable models, the universal asymptotic form is also verified by numerical renormalization group calculations.

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