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Showing papers by "Osaka University published in 2000"


Journal ArticleDOI
07 Dec 2000-Nature
TL;DR: It is shown that cellular response to CpG DNA is mediated by a Toll-like receptor, TLR9, and vertebrate immune systems appear to have evolved a specific Toll- like receptor that distinguishes bacterial DNA from self-DNA.
Abstract: DNA from bacteria has stimulatory effects on mammalian immune cells, which depend on the presence of unmethylated CpG dinucleotides in the bacterial DNA. In contrast, mammalian DNA has a low frequency of CpG dinucleotides, and these are mostly methylated; therefore, mammalian DNA does not have immuno-stimulatory activity. CpG DNA induces a strong T-helper-1-like inflammatory response. Accumulating evidence has revealed the therapeutic potential of CpG DNA as adjuvants for vaccination strategies for cancer, allergy and infectious diseases. Despite its promising clinical use, the molecular mechanism by which CpG DNA activates immune cells remains unclear. Here we show that cellular response to CpG DNA is mediated by a Toll-like receptor, TLR9. TLR9-deficient (TLR9-/-) mice did not show any response to CpG DNA, including proliferation of splenocytes, inflammatory cytokine production from macrophages and maturation of dendritic cells. TLR9-/- mice showed resistance to the lethal effect of CpG DNA without any elevation of serum pro-inflammatory cytokine levels. The in vivo CpG-DNA-mediated T-helper type-1 response was also abolished in TLR9-/- mice. Thus, vertebrate immune systems appear to have evolved a specific Toll-like receptor that distinguishes bacterial DNA from self-DNA.

6,188 citations


Journal ArticleDOI
13 Apr 2000-Nature
TL;DR: This work shows that hyperglycaemia increases the production of reactive oxygen species inside cultured bovine aortic endothelial cells and is prevented by an inhibitor of electron transport chain complex II, by an uncoupler of oxidative phosphorylation, by uncoupling protein-1 and by manganese superoxide dismutase.
Abstract: Normalizing mitochondrial superoxide production blocks three pathways of hyperglycaemic damage

3,750 citations


Journal ArticleDOI
TL;DR: A role is established for Oct-3/4 as a master regulator of pluripotency that controls lineage commitment and the sophistication of critical transcriptional regulators is illustrated and the consequent importance of quantitative analyses are illustrated.
Abstract: Cell fate during development is defined by transcription factors that act as molecular switches to activate or repress specific gene expression programmes. The POU transcription factor Oct-3/4 (encoded by Pou5f1) is a candidate regulator in pluripotent and germline cells and is essential for the initial formation of a pluripotent founder cell population in the mammalian embryo. Here we use conditional expression and repression in embryonic stem (ES) cells to determine requirements for Oct-3/4 in the maintenance of developmental potency. Although transcriptional determination has usually been considered as a binary on-off control system, we found that the precise level of Oct-3/4 governs three distinct fates of ES cells. A less than twofold increase in expression causes differentiation into primitive endoderm and mesoderm. In contrast, repression of Oct-3/4 induces loss of pluripotency and dedifferentiation to trophectoderm. Thus a critical amount of Oct-3/4 is required to sustain stem-cell self-renewal, and up- or downregulation induce divergent developmental programmes. Our findings establish a role for Oct-3/4 as a master regulator of pluripotency that controls lineage commitment and illustrate the sophistication of critical transcriptional regulators and the consequent importance of quantitative analyses.

3,745 citations


Journal ArticleDOI
TL;DR: Results suggest that the decreased plasma adiponectin concentrations in diabetes may be an indicator of macroangiopathy, and weight reduction significantly elevated plasma adip onectin levels in the diabetic subjects as well as the nondiabetic subjects.
Abstract: —Adiponectin is a novel, adipose-specific protein abundantly present in the circulation, and it has antiatherogenic properties. We analyzed the plasma adiponectin concentrations in age- and body mass index (BMI)–matched nondiabetic and type 2 diabetic subjects with and without coronary artery disease (CAD). Plasma levels of adiponectin in the diabetic subjects without CAD were lower than those in nondiabetic subjects (6.6±0.4 versus 7.9±0.5 μg/mL in men, 7.6±0.7 versus 11.7±1.0 μg/mL in women; P<0.001). The plasma adiponectin concentrations of diabetic patients with CAD were lower than those of diabetic patients without CAD (4.0±0.4 versus 6.6±0.4 μg/mL, P<0.001 in men; 6.3±0.8 versus 7.6±0.7 μg/mL in women). In contrast, plasma levels of leptin did not differ between diabetic patients with and without CAD. The presence of microangiopathy did not affect the plasma adiponectin levels in diabetic patients. Significant, univariate, inverse correlations were observed between adiponectin levels and fas...

3,172 citations


Journal ArticleDOI
23 Nov 2000-Nature
TL;DR: A new mode of protein lipidation is reported, in which Apg8 is covalently conjugated to phosphatidylethanolamine through an amide bond between the C-terminal glycine and the amino group of phosph atidyleanolamine, mediated by a ubiquitination-like system.
Abstract: Autophagy is a dynamic membrane phenomenon for bulk protein degradation in the lysosome/vacuole1,2. Apg8/Aut7 is an essential factor for autophagy in yeast3,4,5. We previously found that the carboxy-terminal arginine of nascent Apg8 is removed by Apg4/Aut2 protease, leaving a glycine residue at the C terminus6. Apg8 is then converted to a form (Apg8-X) that is tightly bound to the membrane6. Here we report a new mode of protein lipidation. Apg8 is covalently conjugated to phosphatidylethanolamine through an amide bond between the C-terminal glycine and the amino group of phosphatidylethanolamine. This lipidation is mediated by a ubiquitination-like system. Apg8 is a ubiquitin-like protein that is activated by an E1 protein, Apg7 (refs 7, 8), and is transferred subsequently to the E2 enzymes Apg3/Aut1 (ref. 9). Apg7 activates two different ubiquitin-like proteins, Apg12 (ref. 10) and Apg8, and assigns them to specific E2 enzymes, Apg10 (ref. 11) and Apg3, respectively. These reactions are necessary for the formation of Apg8-phosphatidylethanolamine. This lipidation has an essential role in membrane dynamics during autophagy6.

1,849 citations


Journal ArticleDOI
TL;DR: The possibility that adiponectin, which is naturally present in the blood stream, modulates the inflammatory response of endothelial cells through cross talk between cAMP-PKA and NF-&kgr;B signaling pathways is raised.
Abstract: Background—Among the many adipocyte-derived endocrine factors, we found an adipocyte-derived plasma protein, adiponectin, that was decreased in obesity. We recently demonstrated that adiponectin inhibited tumor necrosis factor-α (TNF-α)–induced expression of endothelial adhesion molecules and that plasma adiponectin level was reduced in patients with coronary artery disease (Circulation. 1999;100:2473–2476). However, the intracellular signal by which adiponectin suppressed adhesion molecule expression was not elucidated. The present study investigated the mechanism of modulation for endothelial function by adiponectin. Methods and Results—The interaction between adiponectin and human aortic endothelial cells (HAECs) was estimated by cell ELISA using biotinylated adiponectin. HAECs were preincubated for 18 hours with 50 μg/mL of adiponectin, then exposed to TNF-α (10 U/mL) or vehicle for the times indicated. NF-κB–DNA binding activity was determined by electrophoretic mobility shift assays. TNF-α–inducible...

1,768 citations


Journal ArticleDOI
TL;DR: In this paper, the synthesis, properties, functions and potential applications for electronic and optoelectronic devices of photo-and electro-active organic materials are discussed, including amorphous molecular materials, titanyl phthalocyanine, oligothiophenes with well-defined structures, and non-conjugated polymers containing pendant oligothophenes or other π-electron systems.
Abstract: This article concentrates on our recent results on several classes of photo- and electro-active organic materials that permit thin film formation and discusses their synthesis, properties, functions and potential applications for electronic and optoelectronic devices. The materials studied include amorphous molecular materials, titanyl phthalocyanine, oligothiophenes with well-defined structures, and non-conjugated polymers containing pendant oligothiophenes or other π-electron systems. The thin films of these materials find potential applications for use in organic electroluminescent, photovoltaic, electrochromic, and other devices.

1,572 citations


Journal ArticleDOI
TL;DR: An intense collimated beam of high-energy protons is emitted normal to the rear surface of thin solid targets irradiated at 1 PW power and peak intensity 3x10(20) W cm(-2).
Abstract: An intense collimated beam of high-energy protons is emitted normal to the rear surface of thin solid targets irradiated at 1 PW power and peak intensity 3x10(20) W cm(-2). Up to 48 J ( 12%) of the laser energy is transferred to 2x10(13) protons of energy >10 MeV. The energy spectrum exhibits a sharp high-energy cutoff as high as 58 MeV on the axis of the beam which decreases in energy with increasing off axis angle. Proton induced nuclear processes have been observed and used to characterize the beam.

1,496 citations


Journal ArticleDOI
TL;DR: In this paper, the authors consider the brane world with a negative tension and derive the effective gravitational equations, which reduce to the conventional Einstein equations in the low energy limit, in which all the matter forces except gravity are confined on the 3-brane in a 5-dimensional spacetime with ${Z}_{2}$ symmetry.
Abstract: We carefully investigate the gravitational equations of the brane world, in which all the matter forces except gravity are confined on the 3-brane in a 5-dimensional spacetime with ${Z}_{2}$ symmetry. We derive the effective gravitational equations on the brane, which reduce to the conventional Einstein equations in the low energy limit. From our general argument we conclude that the first Randall-Sundrum-type theory predicts that the brane with a negative tension is an antigravity world and hence should be excluded from the physical point of view. Their second-type theory where the brane has a positive tension provides the correct signature of gravity. In this latter case, if the bulk spacetime is exactly anti--de Sitter spacetime, generically the matter on the brane is required to be spatially homogeneous because of the Bianchi identities. By allowing deviations from anti--de Sitter spacetime in the bulk, the situation will be relaxed and the Bianchi identities give just the relation between the Weyl tensor and the energy momentum tensor. In the present brane world scenario, the effective Einstein equations cease to be valid during an era when the cosmological constant on the brane is not well defined, such as in the case of the matter dominated by the potential energy of the scalar field.

1,350 citations


Journal ArticleDOI
TL;DR: Assessment of the contribution of the pro-inflammatory cytokine interleukin (IL)-6 to the increased resistance of mucosal T cells against apoptosis in Crohn disease indicates that a pathway of T-cell activation driven by IL-6–sIL-6R contributes to the perpetuation of chronic intestinal inflammation.
Abstract: The pro-inflammatory cytokine interleukin (IL)-6 (refs. 1-5) can bind to cells lacking the IL-6 receptor (IL-6R) when it forms a complex with the soluble IL-6R (sIL-6R) (trans signaling). Here, we have assessed the contribution of this system to the increased resistance of mucosal T cells against apoptosis in Crohn disease (CD), a chronic inflammatory disease of the gastrointestinal tract. A neutralizing antibody against IL-6R suppressed established experimental colitis in various animal models of CD mediated by type 1 T-helper cells, by inducing apoptosis of lamina propria T cells. Similarly, specific neutralization of sIL-6R in vivo by a newly designed gp130-Fc fusion protein caused suppression of colitis activity and induction of apoptosis, indicating that sIL-6R prevents mucosal T-cell apoptosis. In patients with CD, mucosal T cells showed strong evidence for IL-6 trans signaling, with activation of signal transducer and activator of transcription 3, bcl-2 and bcl-xl. Blockade of IL-6 trans signaling caused T-cell apoptosis, indicating that the IL-6-sIL-6R system mediates the resistance of T cells to apoptosis in CD. These data indicate that a pathway of T-cell activation driven by IL-6-sIL-6R contributes to the perpetuation of chronic intestinal inflammation. Specific targeting of this pathway may be a promising new approach for the treatment of CD.

1,248 citations


Journal ArticleDOI
18 May 2000-Nature
TL;DR: In this article, the authors demonstrate that inhibition of RAGE-amphoterin interaction suppressed activation of p44/p42, p38 and SAP/JNK MAP kinases; molecular effector mechanisms importantly linked to tumour proliferation, invasion and expression of matrix metalloproteinases.
Abstract: The receptor for advanced glycation end products (RAGE), a multi-ligand member of the immunoglobulin superfamily of cell surface molecules, interacts with distinct molecules implicated in homeostasis, development and inflammation, and certain diseases such as diabetes and Alzheimer's disease. Engagement of RAGE by a ligand triggers activation of key cell signalling pathways, such as p21ras, MAP kinases, NF-kappaB and cdc42/rac, thereby reprogramming cellular properties. RAGE is a central cell surface receptor for amphoterin, a polypeptide linked to outgrowth of cultured cortical neurons derived from developing brain. Indeed, the co-localization of RAGE and amphoterin at the leading edge of advancing neurites indicated their potential contribution to cellular migration, and in pathologies such as tumour invasion. Here we demonstrate that blockade of RAGE-amphoterin decreased growth and metastases of both implanted tumours and tumours developing spontaneously in susceptible mice. Inhibition of the RAGE-amphoterin interaction suppressed activation of p44/p42, p38 and SAP/JNK MAP kinases; molecular effector mechanisms importantly linked to tumour proliferation, invasion and expression of matrix metalloproteinases.

Journal ArticleDOI
15 May 2000-Oncogene
TL;DR: Since the IL-6/gp130/STAT3 signaling pathway is involved in both B cell growth and differentiation into plasma cells it is likely to play a central role in the generation of plasma cell neoplasias.
Abstract: Members of the IL-6 cytokine family are involved in a variety of biological responses, including the immune response, inflammation, hematopoiesis, and oncogenesis by regulating cell growth, survival, and differentiation. These cytokines use gp130 as a common receptor subunit. The binding of ligand to gp130 activates the JAK/STAT signal transduction pathway, where STAT3 plays a central role in transmitting the signals from the membrane to the nucleus. STAT3 is essential for gp130-mediated cell survival and G1 to S cell-cycle-transition signals. Both c-myc and pim have been identified as target genes of STAT3 and together can compensate for STAT3 in cell survival and cell-cycle transition. STAT3 is also required for gp130-mediated maintenance of the pluripotential state of proliferating embryonic stem cells and for the gp130-induced macrophage differentiation of M1 cells. Furthermore, STAT3 regulates cell movement, such as leukocyte, epidermal cell, and keratinocyte migration. STAT3 also appears to regulate B cell differentiation into antibody-forming plasma cells. Since the IL-6/gp130/STAT3 signaling pathway is involved in both B cell growth and differentiation into plasma cells it is likely to play a central role in the generation of plasma cell neoplasias.

Book ChapterDOI
13 Sep 2000
TL;DR: A novel approach named AGM to efficiently mine the association rules among the frequently appearing substructures in a given graph data set through the extended algorithm of the basket analysis is proposed.
Abstract: This paper proposes a novel approach named AGM to efficiently mine the association rules among the frequently appearing substructures in a given graph data set A graph transaction is represented by an adjacency matrix, and the frequent patterns appearing in the matrices are mined through the extended algorithm of the basket analysis Its performance has been evaluated for the artificial simulation data and the carcinogenesis data of Oxford University and NTP Its high efficiency has been confirmed for the size of a real-world problem

Journal ArticleDOI
TL;DR: To investigate the role of TLR family in host defense against Gram-positive bacteria, mice infected with Staphylococcus aureus were infected with TLR2- and MyD88-deficient mice, indicating that S. a Aureus is recognized not only byTLR2, but also by other TLRfamily members except for TLR4.
Abstract: Toll-like receptor (TLR) family acts as pattern recognition receptors for pathogen-specific molecular patterns. We previously showed that TLR2 recognizes Gram-positive bacterial components whereas TLR4 recognizes LPS, a component of Gram-negative bacteria. MyD88 is shown to be an adaptor molecule essential for TLR family signaling. To investigate the role of TLR family in host defense against Gram-positive bacteria, we infected TLR2- and MyD88-deficient mice with Staphylococcus aureus. Both TLR2- and MyD88-deficient mice were highly susceptible to S. aureus infection, with more enhanced susceptibility in MyD88-deficient mice. Peritoneal macrophages from MyD88-deficient mice did not produce any detectable levels of cytokines in response to S. aureus. In contrast, TLR2-deficient macrophages produced reduced, but significant, levels of the cytokines, and TLR4-deficient macrophages produced the same amounts as wild-type cells, indicating that S. aureus is recognized not only by TLR2, but also by other TLR family members except for TLR4.

Journal ArticleDOI
TL;DR: It is shown here that the nature of the association of Apg8 with membranes changes depending on a series of modifications of the protein itself, which appears to be coupled to the membrane dynamics of autophagy and the Cvt pathway.
Abstract: Autophagy and the Cvt pathway are examples of nonclassical vesicular transport from the cytoplasm to the vacuole via double-membrane vesicles. Apg8/Aut7, which plays an important role in the formation of such vesicles, tends to bind to membranes in spite of its hydrophilic nature. We show here that the nature of the association of Apg8 with membranes changes depending on a series of modifications of the protein itself. First, the carboxy-terminal Arg residue of newly synthesized Apg8 is removed by Apg4/Aut2, a novel cysteine protease, and a Gly residue becomes the carboxy-terminal residue of the protein that is now designated Apg8FG. Subsequently, Apg8FG forms a conjugate with an unidentified molecule “X” and thereby binds tightly to membranes. This modification requires the carboxy-terminal Gly residue of Apg8FG and Apg7, a ubiquitin E1-like enzyme. Finally, the adduct Apg8FG-X is reversed to soluble or loosely membrane-bound Apg8FG by cleavage by Apg4. The mode of action of Apg4, which cleaves both newly synthesized Apg8 and modified Apg8FG, resembles that of deubiquitinating enzymes. A reaction similar to ubiquitination is probably involved in the second modification. The reversible modification of Apg8 appears to be coupled to the membrane dynamics of autophagy and the Cvt pathway.

Journal ArticleDOI
TL;DR: The molecular mechanism of and the physiological roles played by apoptotic DNA fragmentation will be discussed.

Journal ArticleDOI
TL;DR: The results indicate that Runx 2 is a major target gene shared by TGF-β and BMP signaling pathways and that the coordinated action of Runx2 and B MP-activated Smads leads to the induction of osteoblast-specific gene expression in C2C12 cells.
Abstract: When C2C12 pluripotent mesenchymal precursor cells are treated with transforming growth factor beta1 (TGF-beta1), terminal differentiation into myotubes is blocked. Treatment with bone morphogenetic protein 2 (BMP-2) not only blocks myogenic differentiation of C2C12 cells but also induces osteoblast differentiation. The molecular mechanisms governing the ability of TGF-beta1 and BMP-2 to both induce ligand-specific responses and inhibit myogenic differentiation are not known. We identified Runx2/PEBP2alphaA/Cbfa1, a global regulator of osteogenesis, as a major TGF-beta1-responsive element binding protein induced by TGF-beta1 and BMP-2 in C2C12 cells. Consistent with the observation that Runx2 can be induced by either TGF-beta1 or BMP-2, the exogenous expression of Runx2 mediated some of the effects of TGF-beta1 and BMP-2 but not osteoblast-specific gene expression. Runx2 mimicked common effects of TGF-beta1 and BMP-2 by inducing expression of matrix gene products (for example, collagen and fibronectin), suppressing MyoD expression, and inhibiting myotube formation of C2C12 cells. For osteoblast differentiation, an additional effector, BMP-specific Smad protein, was required. Our results indicate that Runx2 is a major target gene shared by TGF-beta and BMP signaling pathways and that the coordinated action of Runx2 and BMP-activated Smads leads to the induction of osteoblast-specific gene expression in C2C12 cells.

Journal ArticleDOI
TL;DR: Single-molecule tracking reveals that the predominant mechanism of dimerization involves the formation of a cell-surface complex of one EGF molecules and an EGFR dimer, followed by the direct arrest of a second EGF molecule, indicating that the EG FR dimers were probably preformed before the binding of the second E GF molecule.
Abstract: The early events in signal transduction from the epidermal growth factor (EGF) receptor (EGFR) are dimerization and autophosphorylation of the receptor, induced by binding of EGF. Here we observe these events in living cells by visualizing single molecules of fluorescent-dye-labelled EGF in the plasma membrane of A431 carcinoma cells. Single-molecule tracking reveals that the predominant mechanism of dimerization involves the formation of a cell-surface complex of one EGF molecule and an EGFR dimer, followed by the direct arrest of a second EGF molecule, indicating that the EGFR dimers were probably preformed before the binding of the second EGF molecule. Single-molecule fluorescence-resonance energy transfer shows that EGF-EGFR complexes indeed form dimers at the molecular level. Use of a monoclonal antibody specific to the phosphorylated (activated) EGFR reveals that the EGFR becomes phosphorylated after dimerization.

Journal ArticleDOI
04 Aug 2000-Science
TL;DR: Preliminary radiation damage experiments substantiate the prediction that fluorites are inherently more radiation resistant than pyrochlores, and may permit the chemical durability and radiation tolerance of potential hosts for actinides and radioactive wastes to be tailored.
Abstract: The radiation performance of a variety of complex oxides is predicted on the basis of a material's propensity to accommodate lattice point defects. The calculations indicate that a particular class of oxides possessing the fluorite crystal structure should accept radiation-induced defects into their lattices far more readily than a structurally similar class of oxides based on the pyrochlore crystal structure. Preliminary radiation damage experiments substantiate the prediction that fluorites are inherently more radiation resistant than pyrochlores. These results may permit the chemical durability and radiation tolerance of potential hosts for actinides and radioactive wastes to be tailored.

Journal ArticleDOI
TL;DR: A decrease in inflammatory cytokine production in tolerant macrophages well correlates with down-regulation of the surface TLR4 expression, which may explain one of the mechanisms for LPS tolerance.
Abstract: Monocytes/macrophages exposed to LPS show reduced responses to second stimulation with LPS, which is termed LPS tolerance. In this study, we investigated molecular mechanism of LPS tolerance in macrophages. Mouse peritoneal macrophages pre-exposed to LPS exhibited reduced production of inflammatory cytokines in a time- and dose-dependent manner. Activation of neither IL-1 receptor-associated kinase nor NF-κB was observed in macrophages that became tolerant by LPS pretreatment, indicating that the proximal event in Toll-like receptor 4 (TLR4)-MyD88-dependent signaling is affected in tolerant macrophages. Although TLR4 mRNA expression significantly decreased within a few hours of LPS pretreatment and returned to the original level at 24 h, the surface TLR4 expression began to decrease within 1 h, with a gradual decrease after that, and remained suppressed over 24 h. A decrease in inflammatory cytokine production in tolerant macrophages well correlates with down-regulation of the surface TLR4 expression, which may explain one of the mechanisms for LPS tolerance.

Journal ArticleDOI
TL;DR: Some fuzzy linear programming methods and techniques from a practical point of view are reviewed and some newly developed ideas and techniques in fuzzy mathematical programming are briey reviewed.

Journal ArticleDOI
TL;DR: In this article, the authors reviewed the regulation of osteoblast differentiation mediated by the local factors such as bone morphogenetic proteins (BMPs) and hedgehogs and the transcription factor, core-binding factor alpha-1 (Cbfa1).
Abstract: Osteoblasts arise from common progenitors with chondrocytes, muscle and adipocytes, and various hormones and local factors regulate their differentiation. We review here regulation of osteoblast differentiation mediated by the local factors such as bone morphogenetic proteins (BMPs) and hedgehogs and the transcription factor, core-binding factor alpha-1 (Cbfa1). BMPs are the most potent regulators of osteoblast differentiation among the local factors. Sonic and Indian hedgehogs are involved in osteoblast differentiation by interacting with BMPs. Cbfa1, a member of the runt domain gene family, plays a major role in the processes of a determination of osteoblast cell lineage and maturation of osteoblasts. Cbfa1 is an essential transcription factor for osteoblast differentiation and bone formation, because Cbfa1-deficient mice completely lacked bone formation due to maturation arrest ofosteoblasts. Although the regulatory mechanism of Cbfa1 expression has not been fully clarified, BMPs are an important local factor that up-regulates Cbfa1 expression. Thus, the intimate interaction between local factors such as BMPs and hedgehogs and the transcription factor, Cbfa1, is important to osteoblast differentiation and bone formation.

Journal ArticleDOI
TL;DR: It is concluded that ATF3 is specifically induced in sensory and motoneurons in the spinal cord following nerve injury and should be regarded as an unique neuronal marker of nerve injury in the nervous system.

Journal ArticleDOI
TL;DR: It was found that tumor growth was markedly attenuated inCOX-2(-/-), but not COX-1(-/-) or wild- type mice, and treatment of wild-type C57BL/6 mice bearing LLC tumors with a selective COX -2 inhibitor reduced tumor growth.
Abstract: Cyclooxygenase-2 (COX-2; Ptgs2) acts as a tumor promoter in rodent models for colorectal cancer, but its precise role in carcinogenesis remains unclear. We evaluated the contribution of host-derived COX-1 and COX-2 in tumor growth using both genetic and pharmacological approaches. Lewis lung carcinoma (LLC) cells grow rapidly as solid tumors when implanted in C57BL/6 mice. We found that tumor growth was markedly attenuated in COX-2(-/-), but not COX-1(-/-) or wild-type mice. Treatment of wild-type C57BL/6 mice bearing LLC tumors with a selective COX-2 inhibitor also reduced tumor growth. A decrease in vascular density was observed in tumors grown in COX-2(-/-) mice when compared with those in wild-type mice. Because COX-2 is expressed in stromal fibroblasts of human and rodent colorectal carcinomas, we evaluated COX-2(-/-) mouse fibroblasts and found a 94% reduction in their ability to produce the proangiogenic factor, VEGF. Additionally, treatment of wild-type mouse fibroblasts with a selective COX-2 inhibitor reduced VEGF production by 92%.

Journal ArticleDOI
TL;DR: An overview of recent findings on the role of Bcl‐2 family members in the life‐or‐death decision of a cell is provided.

Journal ArticleDOI
TL;DR: A collimated beam of fast protons, with energies as high as 1.5 MeV and total number of greater, similar10(9), confined in a cone angle of 40 degrees +/-10 degrees is observed when a high-intensity high-contrast subpicosecond laser pulse is focused onto a thin foil target.
Abstract: A collimated beam of fast protons, with energies as high as 1.5 MeV and total number of $\ensuremath{\gtrsim}{10}^{9}$, confined in a cone angle of $40\ifmmode^\circ\else\textdegree\fi{}\ifmmode\pm\else\textpm\fi{}10\ifmmode^\circ\else\textdegree\fi{}$ is observed when a high-intensity high-contrast subpicosecond laser pulse is focused onto a thin foil target. The protons, which appear to originate from impurities on the front side of the target, are accelerated over a region extending into the target and exit out the back side in a direction normal to the target surface. Acceleration field gradients $\ensuremath{\sim}10\mathrm{GeV}/\mathrm{cm}$ are inferred. The maximum proton energy can be explained by the charge-separation electrostatic-field acceleration due to ``vacuum heating.''

Journal ArticleDOI
TL;DR: The focus of this article is how SOX proteins specifically pair off with respective partner factors and, as a consequence, select distinct sets of genes as their regulatory targets.

Journal ArticleDOI
TL;DR: In this article, a simplified model of binuclear manganese oxide, Mn2O2, using spin-unrestricted Hartree-Fock (UHF), spin-polarized density functional (DFT) and UHF+DFT hybrid methods is presented.


Journal ArticleDOI
TL;DR: The MALP-2-induced activation of intracellular signaling molecules was fully dependent on both TLR2 and MyD88, and there was a strong preference for the R-MALP in the recognition by its functional receptor,TLR2.
Abstract: Mycoplasmas and their membranes are potent activators of macrophages, the active principle being lipoproteins and lipopeptides. Two stereoisomers of the mycoplasmal lipopeptide macrophage-activating lipopeptide-2 (MALP-2) differing in the configuration of the lipid moiety were synthesized and compared in their macrophage-activating potential, the R-MALP being >100 times more active than the S-MALP in stimulating the release of cytokines, chemokines, and NO. To assess the role of the Toll-like receptor (TLR) family in mycoplasmal lipopeptide signaling, the MALP-2-mediated responses were analyzed using macrophages from wild-type, TLR2-, TLR4-, and MyD88-deficient mice. TLR2- and MyD88-deficient cells showed severely impaired cytokine productions in response to R- and S-MALP. The MALP-induced activation of intracellular signaling molecules was fully dependent on both TLR2 and MyD88. There was a strong preference for the R-MALP in the recognition by its functional receptor, TLR2.