WorldWideScience

Sample records for tcdd induces matrix

  1. TCDD induces dermal accumulation of keratinocyte-derived matrix metalloproteinase-10 in an organotypic model of human skin

    Energy Technology Data Exchange (ETDEWEB)

    De Abrew, K. Nadira [Molecular and Environmental Toxicology Center, University of Wisconsin—Madison, Madison, WI 53706 (United States); Thomas-Virnig, Christina L.; Rasmussen, Cathy A. [Department of Pathology, University of Wisconsin—Madison, Madison, WI 53706 (United States); Bolterstein, Elyse A. [Molecular and Environmental Toxicology Center, University of Wisconsin—Madison, Madison, WI 53706 (United States); Schlosser, Sandy J. [Department of Pathology, University of Wisconsin—Madison, Madison, WI 53706 (United States); Allen-Hoffmann, B. Lynn, E-mail: blallenh@wisc.edu [Molecular and Environmental Toxicology Center, University of Wisconsin—Madison, Madison, WI 53706 (United States); Department of Pathology, University of Wisconsin—Madison, Madison, WI 53706 (United States)

    2014-05-01

    The epidermis of skin is the first line of defense against the environment. A three dimensional model of human skin was used to investigate tissue-specific phenotypes induced by the environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Continuous treatment of organotypic cultures of human keratinocytes with TCDD resulted in intracellular spaces between keratinocytes of the basal and immediately suprabasal layers as well as thinning of the basement membrane, in addition to the previously reported hyperkeratinization. These tissue remodeling events were preceded temporally by changes in expression of the extracellular matrix degrading enzyme, matrix metalloproteinase-10 (MMP-10). In organotypic cultures MMP-10 mRNA and protein were highly induced following TCDD treatment. Q-PCR and immunoblot results from TCDD-treated monolayer cultures, as well as indirect immunofluorescence and immunoblot analysis of TCDD-treated organotypic cultures, showed that MMP-10 was specifically contributed by the epidermal keratinocytes but not the dermal fibroblasts. Keratinocyte-derived MMP-10 protein accumulated over time in the dermal compartment of organotypic cultures. TCDD-induced epidermal phenotypes in organotypic cultures were attenuated by the keratinocyte-specific expression of tissue inhibitor of metalloproteinase-1, a known inhibitor of MMP-10. These studies suggest that MMP-10 and possibly other MMP-10-activated MMPs are responsible for the phenotypes exhibited in the basement membrane, the basal keratinocyte layer, and the cornified layer of TCDD-treated organotypic cultures. Our studies reveal a novel mechanism by which the epithelial–stromal microenvironment is altered in a tissue-specific manner thereby inducing structural and functional pathology in the interfollicular epidermis of human skin. - Highlights: • TCDD causes hyperkeratosis and basement membrane changes in a model of human skin. • TCDD induces MMP-10 expression in organotypic cultures

  2. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces matrix metalloproteinase (MMP) expression and invasion in A2058 melanoma cells

    International Nuclear Information System (INIS)

    Villano, C.M.; Murphy, K.A.; Akintobi, A.; White, L.A.

    2006-01-01

    There has been a 34% increase in melanoma related mortality in the United States from 1973 to 1992. Although few successful treatments for malignant melanoma exist, it is known that genetic susceptibility and environmental factors contribute to the initiation and progression of melanoma. Excessive UV exposure is considered the main etiological factor in melanoma initiation, however, epidemiological and experimental evidence suggests that exposure to environmental carcinogens contribute to melanoma. We propose that exposure to environmental chemicals that activate the aryl hydrocarbon receptor pathway contribute to melanoma progression, specifically through stimulation of the expression and activity of the matrix metalloproteinases (MMPs). Therefore, we investigated the effect of AhR activation on normal human melanocytes and several melanoma cell lines. The data presented here demonstrate that normal melanocytes and melanoma cells express the AhR and Arnt and are responsive to activation by TCDD. Furthermore, activation of this pathway in transformed melanoma cells (A2058) results in increased expression and activity of MMP-1, MMP-2 and MMP-9, as well as increased invasion using in vitro invasion assays. Furthermore, TCDD-induced expression of the MMP-1 promoter in melanoma cells appears to require different elements than those required in untransformed cells, indicating that this pathway may have multiple mechanisms for activation of MMP expression

  3. TCDD Induces the Hypoxia-Inducible Factor (HIF-1α Regulatory Pathway in Human Trophoblastic JAR Cells

    Directory of Open Access Journals (Sweden)

    Tien-Ling Liao

    2014-09-01

    Full Text Available The exposure to dioxin can compromise pregnancy outcomes and increase the risk of preterm births. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD has been demonstrated to induce placental hypoxia at the end of pregnancy in a rat model, and hypoxia has been suggested to be the cause of abnormal trophoblast differentiation and placental insufficiency syndromes. In this study, we demonstrate that the non-hypoxic stimulation of human trophoblastic cells by TCDD strongly increased hypoxia inducible factor-1 alpha (HIF-1α stabilization. TCDD exposure induced the generation of reactive oxygen species (ROS and nitric oxide. TCDD-induced HIF-1α stabilization and Akt phosphorylation was inhibited by pretreatment with wortmannin (a phosphatidylinositol 3-kinase (PI3K inhibitor or N-acetylcysteine (a ROS scavenger. The augmented HIF-1α stabilization by TCDD occurred via the ROS-dependent activation of the PI3K/Akt pathway. Additionally, a significant increase in invasion and metallomatrix protease-9 activity was found in TCDD-treated cells. The gene expression of vascular endothelial growth factor and placental growth factor was induced upon TCDD stimulation, whereas the protein levels of peroxisome proliferator-activated receptor γ (PPARγ, PPARγ coactivator-1α, mitochondrial transcription factor, and uncoupling protein 2 were decreased. Our results indicate that an activated HIF-1α pathway, elicited oxidative stress, and induced metabolic stress contribute to TCDD-induced trophoblastic toxicity. These findings may provide molecular insight into the TCDD-induced impairment of trophoblast function and placental development.

  4. TCDD induces cell migration via NFATc1/ATX-signaling in MCF-7 cells.

    Science.gov (United States)

    Seifert, Anja; Rau, Steffi; Küllertz, Gerhard; Fischer, Bernd; Santos, Anne Navarrete

    2009-01-10

    Breast cancer is characterized, among others, by the concurrence of lipophilic xenobiotica such as 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD) with hypoxic tissue conditions. This condition activates the transcription factors hypoxia inducible factor-1alpha (HIF-1alpha) and aryl hydrocarbon receptor (AhR) that are known to promote tumor progression. An interrelation between these transcription factors and nuclear factor of activated T-cells (NFAT) was implied by gene array analysis. In the present study, the interplay of the three transcription factors was studied and correlated with the migration of MCF-7 cells in response to TCDD and/or hypoxia. An AhR-activation by 10nM TCDD and HIF-1alpha activation by 5% oxygen induced activation of NFATc1. The effects were inhibited by cyclosporine A (CsA), suggesting that the activation of NFAT by AhR or HIF-1alpha signaling is calcineurin-dependent. The expression/activity of the NFAT target gene autotaxin (ATX) was increased. ATX is known to stimulate migration of tumor cells. The hydrolysis product of ATX, lysophosphatidic acid (LPA), increased the migration of MCF-7 cells under normoxia but not under hypoxia. This effect correlated with increased migration observed after TCDD treatment. Hypoxia did not promote migration of MCF-7 cells, suggesting that ATX down-stream signaling was inhibited by hypoxia. In conclusion, the TCDD-mediated activation of NFATc1 is suggested to promote cell migration via ATX/LPA-signaling.

  5. Involvement of COX2–thromboxane pathway in TCDD-induced precardiac edema in developing zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Teraoka, Hiroki, E-mail: hteraoka@rakuno.ac.jp [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu (Japan); Okuno, Yuki; Nijoukubo, Daisuke; Yamakoshi, Ayumi [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu (Japan); Peterson, Richard E. [School of Pharmacy, University of Wisconsin, Madison, WI (United States); Stegeman, John J. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA (United States); Kitazawa, Takio; Hiraga, Takeo [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu (Japan); Kubota, Akira [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu (Japan); Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA (United States)

    2014-09-15

    Highlights: • We establish a new indicator of pericardial edema in developing zebrafish (precardiac edema). • Property of precardiac edema by TCDD is similar to that for conventional pericardial edema. • COX2b (but not COX2a)–thromboxane pathway is involved in precardiac edema by TCDD. - Abstract: The cardiovascular system is one of the most characteristic and important targets for developmental toxicity by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in fish larvae. However, knowledge of the mechanism of TCDD-induced edema after heterodimerization of aryl hydrocarbon receptor type 2 (AHR2) and AHR nuclear translocator type 1 (ARNT1) is still limited. In the present study, microscopic analysis with a high-speed camera revealed that TCDD increased the size of a small cavity between the heart and body wall in early eleutheroembryos, a toxic effect that we designate as precardiac edema. A concentration–response curve for precardiac edema at 2 days post fertilization (dpf) showed close similarity to that for conventional pericardial edema at 3 dpf. Precardiac edema caused by TCDD was reduced by morpholino knockdown of AHR2 and ARNT1, as well as by an antioxidant (ascorbic acid). A selective inhibitor of cyclooxygenase type 2 (COX2), NS398, also markedly inhibited TCDD-induced precardiac edema. A thromboxane receptor (TP) antagonist, ICI-192,605 almost abolished TCDD-induced precardiac edema and this effect was canceled by U46619, a TP agonist, which was not influential in the action of TCDD by itself. Knockdown of COX2b and thromboxane A synthase 1 (TBXS), but not COX2a, strongly reduced TCDD-induced precardiac edema. Knockdown of COX2b was without effect on mesencephalic circulation failure caused by TCDD. The edema by TCDD was also inhibited by knockdown of c-mpl, a thrombopoietin receptor necessary for thromobocyte production. Finally, induction of COX2b, but not COX2a, by TCDD was seen in eleutheroembryos at 3 dpf. These results suggest a role of the COX2b

  6. Understanding the toxic potencies of xenobiotics inducing TCDD/TCDF-like effects.

    Science.gov (United States)

    Şahin, A D; Saçan, M T

    2018-02-01

    Toxic potencies of xenobiotics such as halogenated aromatic hydrocarbons inducing 2,3,7,8-tetrachlorodibenzo-p-dioxin/2,3,7,8-tetrachlorodibenzofuran (TCDD/TCDF)-like effects were investigated by quantitative structure-toxicity relationships (QSTR) using their aryl hydrocarbon receptor (AhR) binding affinity data. A descriptor pool was created using the SPARTAN 10, DRAGON 6.0 and ADMET 8.0 software packages, and the descriptors were selected using QSARINS (v.2.2.1) software. The QSTR models generated for AhR binding affinities of chemicals with TCDD/TCDF-like effects were internally and externally validated in line with the Organization of Economic Co-operation and Development (OECD) principles. The TCDD-based model had six descriptors from DRAGON 6.0 and ADMET 8.0, whereas the TCDF-based model had seven descriptors from DRAGON 6.0. The predictive ability of the generated models was tested on a diverse group of chemicals including polychlorinated/brominated biphenyls, dioxins/furans, ethers, polyaromatic hydrocarbons with fused heterocyclic rings (i.e. phenoxathiins, thianthrenes and dibenzothiophenes) and polyaromatic hydrocarbons (i.e. halogenated naphthalenes and phenanthrenes) with no AhR binding data. For the external set chemicals, the structural coverage of the generated models was 90% and 89% for TCDD and TCDF-like effects, respectively.

  7. Nrf2 protects against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced oxidative injury and steatohepatitis

    International Nuclear Information System (INIS)

    Lu Hong; Cui Wei; Klaassen, Curtis D.

    2011-01-01

    Previous studies demonstrate that Nrf2, a master regulator of antioxidative responses, is essential in mediating induction of many antioxidative enzymes by acute activation of the AhR. However, the role of Nrf2 in protecting against oxidative stress and DNA damage induced by sustained activation of the AhR remains unknown and was investigated herein. Tissue and blood samples were collected from wild-type (WT) and Nrf2-null mice 21 days after administration of a low-toxic dose (10 μg/kg ip) of TCDD. Only Nrf2-null mice lost body weight after TCDD treatment; however, blood levels of ALT were not markedly changed in either genotype, indicating a lack of extensive necrosis. Compared to livers of TCDD-treated WT mice, livers of TCDD-treated Nrf2-null mice had: 1) degenerated hepatocytes, lobular inflammation, marked fat accumulation, and higher mRNA expression of inflammatory and fibrotic genes; 2) depletion of glutathione, elevation in lipid peroxidation and marker of DNA damage; 3) attenuated induction of phase-II enzymes Nqo1, Gsta1/2, and Ugt2b35 mRNAs, but higher induction of cytoprotective Ho-1, Prdx1, Trxr1, Gclc, and Epxh1 mRNAs; 4) higher mRNA expression of Fgf21 and triglyceride-synthesis genes, but down-regulation of bile-acid-synthesis genes and cholesterol-efflux transporters; and 5) trend of induction/activation of c-jun and NF-kB. Additionally, TCDD-treated Nrf2-null mice had impaired adipogenesis in white adipose tissue. In conclusion, Nrf2 protects livers of mice against oxidative stress, DNA damage, and steatohepatitis induced by TCDD-mediated sustained activation of the AhR. The aggravated hepatosteatosis in TCDD-treated Nrf2-null mice is due to increased lipogenesis in liver and impaired lipogenesis in white adipose tissue. - Highlights: → TCDD causes hepatosteatosis and induction of Nrf2-target genes in wild-type mice. → TCDD causes weight loss, oxidative injury, and steatohepatitis in Nrf2-null mice. → Livers of TCDD-treated Nrf2-null mice

  8. LncRNA H19 and Target Gene-mediated Cleft Palate Induced by TCDD.

    Science.gov (United States)

    Gao, Li Yun; Zhang, Feng Quan; Zhao, Wei Hui; Han, Guang Liang; Wang, Xiao; Li, Qiang; Gao, Shan Shan; Wu, Wei Dong

    2017-09-01

    This study investigated the role of long non-coding RNAs (lncRNAs) in the development of the palatal tissues. Cleft palates in mice were induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Expression levels of long non-coding RNA H19 (lncRNA H19) and insulin-like growth factor 2 (IGF2) gene were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The rate of occurrence of cleft palate was found to be 100% by TCDD exposure, and TCDD could cause short upper limb, cerebral fissure, webbed neck, and short neck. The expression levels of lncRNA H19 and IGF2 gene specifically showed embryo age-related differences on E13, E14, and E15 in the palatal tissues. The expression levels of lncRNA H19 and IGF2 gene showed an inverse relationship on E13, E14, and E15. These findings demonstrated that lncRNA H19 and IGF2 can mediate the development of mouse cleft palate. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  9. Comparative Study of Folic Acid and α-Naphthoflavone on Reducing TCDD-Induced Cleft Palate in Fetal Mice.

    Science.gov (United States)

    Yuan, Xingang; He, Xiaomeng; Zhang, Xuan; Liu, Cuiping; Wang, Chen; Qiu, Lin; Pu, Wei; Fu, Yuexian

    2017-03-01

      Tocompare the effect of folic acid (FA) and α-naphthoflavone on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced cleft palate in fetal mice.   Pregnant mice were randomly divided into seven groups. The mice treated with corn oil were used as a negative control. The mice in the other six groups were given a single dose of 28 μg/kg TCDD on GD 10 by gavage. For FA treatment, TCDD-treated mice were also dosed with 5, 10, and 15 mg/kg FA on GD 10, while for α-naphthoflavone treatment, the mice received a single dose of 50 μg/kg or 5 mg/kg α-naphthoflavone on GD 10.   Fetal mice palates were imaged using light and scanning electron microscopy on GD 13.5, GD 14.5, and GD 15.5, and cleft palate were recorded on GD 17.5. The expression of guanosine diphosphate dissociation inhibitor (GDI) in fetal mice palate on GD 15.5 was examined by immunohistochemistry.   TCDD successfully induced cleft palate. Ten mg/ml FA and 5 mg/ml α-naphthoflavone significantly reduced TCDD-induced cleft palate. FA and α-naphthoflavone partly reduced TCDD-induced cleft palate but did not affect the expression of Rho GDI.   FA and α-naphthoflavone may reduce the generation of reactive oxygen species, inhibit MEE apoptosis through anti-oxidation, and increase filopodia and MEE movement. This may result in restoration of the ultrastructure of the palatal surface to a normal state, leading to the fusion and formation of complete palate in TCDD-treated fetal mice.

  10. TCDD Induced Pericardial Edema and Relative COX-2 Expression in Medaka (Oryzias Latipes) Embryos

    Science.gov (United States)

    Dong, Wu; Matsumura, Fumio; Kullman, Seth W.

    2010-01-01

    Exposure to dioxin and other aryl hydrocarbon receptor (AhR) ligands results in multiple, specific developmental cardiovascular phenotypes including pericardial edema and circulatory failure in small aquarium fish models. Although phenotypes are well described, mechanistic underpinnings for such toxicities remain elusive. Here we suggest that AhR activation results in stimulation of inflammation and “eicosanoid” pathways, which contribute to the observed developmental, cardiovascular phenotypes. We demonstrate that medaka embryos exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (0.05–1 ppb) during early development result in a dose-related increase in the prevalence of pericardial edema and that this phenotype correlates with an increase in cyclooxygenase-2 (COX-2) gene expression. Those individuals exhibiting the edema phenotype had significantly greater COX-2 mRNA than their nonedematous cohort. Selective pharmacological inhibition of COX-2, with NS-398, and genetic knock down of COX-2 with a translation initiation morpholino significantly attenuated prevalence and severity of edema phenotype. Subsequently, exposures of medaka embryos to arachidonic acid (AA) resulted in recapitulation of the pericardial edema phenotype and significantly increased COX-2 expression only in those individuals exhibiting the edema phenotype compared with their nonedematous cohort. AA exposure does not result in significant induction of cytochrome P450 1A expression, suggesting that pericardial edema can be induced independent of AhR/aryl hydrocarbon receptor nuclear translocator/dioxin response element interactions. Results from this study demonstrate that developmental exposure to TCDD results in an induction of inflammatory mediators including COX-2, which contribute to the onset, and progression of heart dysmorphogenesis in the medaka model. PMID:20801906

  11. The PERK-eIF2α signaling pathway is involved in TCDD-induced ER stress in PC12 cells.

    Science.gov (United States)

    Duan, Zhiqing; Zhao, Jianya; Fan, Xikang; Tang, Cuiying; Liang, Lingwei; Nie, Xiaoke; Liu, Jiao; Wu, Qiyun; Xu, Guangfei

    2014-09-01

    Studies have shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces apoptotic cell death in neuronal cells. However, whether this is the result of endoplasmic reticulum (ER) stress-mediated apoptosis remains unknown. In this study, we determined whether ER stress plays a role in the TCDD-induced apoptosis of pheochromocytoma (PC12) cells and primary neurons. PC12 cells were exposed to different TCDD concentrations (1, 10, 100, 200, or 500nM) for varying lengths of time (1, 3, 6, 12, or 24h). TCDD concentrations much higher than 10nM (100, 200, or 500nM) markedly increased glucose-regulated protein (GRP78) and C/EBP homologous protein (CHOP) levels, which are hallmarks of ER stress. We also evaluated the effects of TCDD on ER morphology in PC12 cells and primary neurons that were treated with different TCDD concentrations (1, 10, 50, or 200nM) for 24h. Ultrastructural ER alterations were observed with transmission electron microscopy in PC12 cells and primary neurons treated with high concentrations of TCDD. Furthermore, TCDD-induced ER stress significantly promoted the activation of the PKR-like ER kinase (PERK), a sensor for the unfolded protein response (UPR), and its downstream target eukaryotic translation initiation factor 2 α (eIF2α); in contrast, TCDD did not appear to affect inositol-requiring enzyme 1 (IRE1) and activating transcription factor 6 (ATF6), two other UPR sensors. Importantly, TCDD significantly inhibited eIF2α phosphorylation and triggered apoptosis in PC12 cells after 6-24h of treatment. Salubrinal, which activates the PERK-eIF2α pathway, significantly enhanced eIF2α phosphorylation in PC12 cells and attenuated the TCDD-induced cell death. In contrast, knocking down eIF2α using small interfering RNA markedly enhanced TCDD-induced cell death. Together, these results indicate that the PERK-eIF2α pathway plays an important role in TCDD-induced ER stress and apoptosis in PC12 cells. Copyright © 2014 Elsevier Inc. All rights

  12. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induces oxidative stress in the epididymis and epididymal sperm of adult rats

    Energy Technology Data Exchange (ETDEWEB)

    Latchoumycandane, C.; Chitra, K.C.; Mathur, P.P. [School of Life Sciences, Pondicherry University, 605 014, Pondicherry (India)

    2003-05-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is one of the most potent environmental contaminants, which has been shown to induce oxidative stress in testis and epididymal sperm of rats. However, the nature and mechanism of action of TCDD on the epididymis is not clear. The aim of the present study was to investigate whether induction of oxidative stress in epididymal sperm was direct effect of TCDD on epididymis. In the present studies, TCDD (0.1, 1.0 and 10 {mu}g/kg body weight per day) was administered orally to rats for 4 days. Twenty-four hours after the last treatment the animals were killed using anesthetic ether. Both epididymides were dissected out and epididymal sperm were collected by cutting the epididymides into small pieces in Ham's F-12 medium at 35 C. The epididymal sperm and caput, corpus and cauda epididymides were homogenized and used for biochemical studies. Epididymal sperm counts did not decrease in the rats treated with TCDD. Administration of TCDD increased the production of reactive oxygen species such as hydrogen peroxide while the activities of antioxidant enzymes superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase were found to be decreased in the epididymal sperm as well as in cauda epididymides. Lipid peroxidation also increased in the epididymal sperm and in the various regions of the epididymides after exposure to TCDD. The results indicated that TCDD induces oxidative stress in the epididymis and epididymal sperm by decreasing the antioxidant enzymes through induction of reactive oxygen species. Thus, the adverse effects of TCDD on the epididymal sperm were due to direct effect of TCDD on epididymis. (orig.)

  13. Epidermal Growth Factor Receptor Kinase Inhibitors Synergize with TCDD to Induce CYP1A1/1A2 in Human Breast Epithelial MCF10A Cells.

    Science.gov (United States)

    Joiakim, Aby; Mathieu, Patricia A; Shelp, Catherine; Boerner, Julie; Reiners, John J

    2016-05-01

    CYP1A1 and CYP1A2 are transcriptionally activated in the human normal breast epithelial cell line MCF10A following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Shifting MCF10A cultures to medium deficient in serum and epidermal growth factor (EGF) caused rapid reductions in the activated (i.e., phosphorylated) forms of extracellular regulated kinases (ERKs) and the epidermal growth factor receptor (EGFR). Shifting to serum/EGF-deficient medium also enhanced TCDD-mediated induction of cytochrome P450 (CYP)1A1 Treatment of cells cultured in complete medium with the EGFR inhibitors gefitinib (Iressa), AG1478, and CI-1033 resulted in concentration-dependent reductions of active EGFR and ERKs, and increased CYP1A1 mRNA content ∼3- to 18-fold above basal level. EGFR inhibitors synergized with TCDD and resulted in transient CYP1A1 and CYP1A2 mRNA accumulations ∼8-fold greater (maximum at 5 hours) than that achieved with only TCDD. AG1478, gefitinib, and TCDD individually induced small increases (∼1.2- to 2.5-fold) in CYP1A1 protein content but did not cause additive or synergistic accumulations of CYP1A1 protein when used in combination. The mitogen-activated protein kinase kinase inhibitor PD184352 inhibited ERK and EGFR activation in a concentration-dependent fashion without causing CYP1A1 mRNA accumulation. However, cotreatment with PD184352 potentiated TCDD-mediated CYP1A1 induction. TCDD-mediated induction of CYP1A1 in MCF7-TET on-EGFR cells, a MCF7 variant in which EGFR expression can be controlled, was not affected by the activity status of EGFR or ERKs. Hence, EGFR signaling mutes both basal and ligand-induced expression of two aryl hydrocarbon receptor-responsive P450s in MCF10A cultures. However, these effects are cell context-dependent. Furthermore, CYP1A1 mRNA and protein abundance are not closely coupled in MCF10A cultures. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  14. Effects of 2,3,7,8-TCDD and PCB 126 on human thymic epithelial cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Riecke, Kai [Institut fuer Klinische Pharmakologie und Toxikologie (Abt. Toxikologie), Universitaetsklinikum Benjamin Franklin, Freie Universitaet Berlin, Garystrasse 5, 14195, Berlin (Germany); Experimental Toxicology, Schering AG, 10334, Berlin (Germany); Schmidt, Andre; Stahlmann, Ralf [Institut fuer Klinische Pharmakologie und Toxikologie (Abt. Toxikologie), Universitaetsklinikum Benjamin Franklin, Freie Universitaet Berlin, Garystrasse 5, 14195, Berlin (Germany)

    2003-06-01

    2,3,7,8-Tetrachloro-dibenzo-p-dioxin (TCDD) is a ubiquitously distributed xenobiotic. The adverse effects of TCDD on the mammalian immune system have been studied for decades, but it is still unclear whether TCDD has direct effects on T-lymphocytes or whether it acts via the thymic microenvironment. We have studied the effects of TCDD on primary cultures of human thymic epithelial cells (TEC) focusing on differentiation markers, integrins and adhesion molecules involved in cell-cell and in cell-matrix interactions. TEC were treated with TCDD at concentrations of 0.001, 0.01, 0.1, 1.0 or 10.0 nM or with 100 nM PCB 126 (3,3',4,4',5-pentachlorobiphenyl) for 3 days, and were then analysed by flow cytometry for expression of surface antigens using monoclonal antibodies against Hassall's bodies (TE-8, TE-16) or against surface structures such as CD29, CD49b, CD49e, CD49f, CD51, CD54, CD58, CD61 and CD106. At TCDD concentrations as low as 0.01 nM we found a significant increase in terminally differentiated, TE-16-positive TEC; at a ten-fold greater concentration the number of cells marked with the TE-8 antibody was also increased. With both markers the most pronounced effect (approximately +15%) was observed at 1 nM TCDD. An increase of cells expressing the integrin {alpha}-chains CD49b, CD49e and CD51 as well as CD54 was observed at concentrations of 0.1 nM TCDD or higher. The proportion of cells expressing CD106 or CD49f decreased significantly upon treatment with TCDD. No effects on the integrin {beta}-chains CD29 and CD61 could be detected. Overall, PCB 126 induced similar changes to TCDD. In summary, TCDD and a coplanar PCB induced terminal differentiation of human TEC along with changes of integrins and other adhesion molecules. These receptors and their interplay with the extracellular matrix have key functions in the maturation of T-lymphocytes and it is plausible that their alteration would be involved in TCDD-induced immunotoxicity. (orig.)

  15. Dioxin (TCDD induces epigenetic transgenerational inheritance of adult onset disease and sperm epimutations.

    Directory of Open Access Journals (Sweden)

    Mohan Manikkam

    Full Text Available Environmental compounds can promote epigenetic transgenerational inheritance of adult-onset disease in subsequent generations following ancestral exposure during fetal gonadal sex determination. The current study examined the ability of dioxin (2,3,7,8-tetrachlorodibenzo[p]dioxin, TCDD to promote epigenetic transgenerational inheritance of disease and DNA methylation epimutations in sperm. Gestating F0 generation females were exposed to dioxin during fetal day 8 to 14 and adult-onset disease was evaluated in F1 and F3 generation rats. The incidences of total disease and multiple disease increased in F1 and F3 generations. Prostate disease, ovarian primordial follicle loss and polycystic ovary disease were increased in F1 generation dioxin lineage. Kidney disease in males, pubertal abnormalities in females, ovarian primordial follicle loss and polycystic ovary disease were increased in F3 generation dioxin lineage animals. Analysis of the F3 generation sperm epigenome identified 50 differentially DNA methylated regions (DMR in gene promoters. These DMR provide potential epigenetic biomarkers for transgenerational disease and ancestral environmental exposures. Observations demonstrate dioxin exposure of a gestating female promotes epigenetic transgenerational inheritance of adult onset disease and sperm epimutations.

  16. Cell death and impairment of glucose-stimulated insulin secretion induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the β-cell line INS-1E

    International Nuclear Information System (INIS)

    Piaggi, Simona; Novelli, Michela; Martino, Luisa; Masini, Matilde; Raggi, Chiara; Orciuolo, Enrico; Masiello, Pellegrino; Casini, Alessandro; De Tata, Vincenzo

    2007-01-01

    The aim of this research was to characterize 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity on the insulin-secreting β-cell line INS-1E. A sharp decline of cell survival (below 20%) was observed after 1 h exposure to TCDD concentrations between 12.5 and 25 nM. Ultrastructurally, β-cell death was characterized by extensive degranulation, appearance of autophagic vacuoles, and peripheral nuclear condensation. Cytotoxic concentrations of TCDD rapidly induced a dose-dependent increase in intracellular calcium concentration. Blocking calcium entry by EGTA significantly decreased TCDD cytotoxicity. TCDD was also able to rapidly induce mitochondrial depolarization. Interestingly, 1 h exposition of INS-1E cells to very low TCDD concentrations (0.05-1 nM) dramatically impaired glucose-stimulated but not KCl-stimulated insulin secretion. In conclusion, our results clearly show that TCDD exerts a direct β-cell cytotoxic effect at concentrations of 15-25 nM, but also markedly impairs glucose-stimulated insulin secretion at concentrations 20 times lower than these. On the basis of this latter observation we suggest that pancreatic β-cells could be considered a specific and sensitive target for dioxin toxicity

  17. Rat embryonic palatal shelves respond to TCDD in organ culture

    International Nuclear Information System (INIS)

    Abbott, B.D.; Birnbaum, L.S.

    1990-01-01

    TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin), a highly toxic environmental contaminant, is teratogenic in mice, inducing cleft palate (CP) and hydronephrosis at doses which are not overtly maternally or embryo toxic. Palatal shelves of embryonic mice respond to TCDD, both in vivo and in organ culture, with altered differentiation of medial epithelial cells. By contrast, in the rat TCDD produces substantial maternal, embryonic, and fetal toxicity, including fetal lethality, with few malformations. In this study the possible effects of maternal toxicity on induction of cleft palate were eliminated by exposure of embryonic rat palatal shelves in organ culture. The shelves were examined for specific TCDD-induced alterations in differentiation of the medial cells. On Gestation Day (GD) 14 or 15 palatal shelves from embryonic F344 rats were placed in organ culture for 2 to 3 days (IMEM:F12 medium, 5% FBS, 0.1% DMSO) containing 0, 1 x 10(-8), 1 x 10(-9), 1 x 10(-10), or 5 x 10(-11) M TCDD. The medial epithelial peridermal cells degenerated on shelves exposed to control media or 5 x 10(-11) M TCDD. Exposure to 10(-10), 10(-9), and 10(-8) M TCDD inhibited this degeneration in 20, 36, and 60% of the shelves, respectively, and was statistically significant at the two highest doses. A normally occurring decrease in [3H]TdR incorporation was inhibited in some GD 15 shelves cultured with 10(-10) and 10(-9) M TCDD. The medial cells of TCDD-exposed shelves continued to express high levels of immunohistochemically detected EGF receptors. The altered differentiation of rat medial epithelium is similar to that reported for TCDD-exposed mouse medial cells in vivo and in vitro. However, in order to obtain these responses, the cultured rat shelves require much higher concentrations of TCDD than the mouse shelves

  18. Matrix models of induced QCD

    International Nuclear Information System (INIS)

    Makeenko, Yu.

    1994-01-01

    I review recent works on the problem of inducing large-N QCD by matrix fields. In the first part of the talk I describe the matrix models which induce large-N QCD and present the results of studies of their phase structure by the standard lattice technology (in particular, by the mean field method). The second part is devoted to the exact solution of these models in the strong coupling region by means of the loop equations. I describe the solution of the Kazakov-Migdal model with the quadratic and logarithmic potentials as well as that of analogous fermionic models with the quadratic potential. (orig.)

  19. TCDD promoted EMT of hFPECs via AhR, which involved the activation of EGFR/ERK signaling

    International Nuclear Information System (INIS)

    Gao, Zhan; Bu, Yongjun; Liu, Xiaozhuan; Wang, Xugang; Zhang, Guofu; Wang, Erhui; Ding, Shibin; Liu, Yongfeng; Shi, Ruling; Li, Qiaoyun; Fu, Jianhong; Yu, Zengli

    2016-01-01

    One critical step of second palatal fusion is the newly formed medial epithelia seam (MES) disintegration, which involves apoptosis, epithelial to mesenchymal transition (EMT), and cell migration. Although the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produces cleft palate at high rates, little is known about the effects of TCDD exposure on the fate of palatal epithelial cells. By using primary epithelial cells isolated from human fetal palatal shelves (hFPECs), we show that TCDD increased cell proliferation and EMT, as demonstrated by increased the epithelial markers (E-cadherin and cytokeratin14) and enhanced the mesenchymal markers (vimentin and fibronectin), but had no effect on cell migration and apoptosis. TCDD exposure led to a dose-dependent increase in Slug protein expression. Coimmunoprecipitation revealed that TCDD promoted AhR to form a protein complex with Slug. ChIP assay confirmed that TCDD exposure recruited AhR to the xenobiotic responsive element of Slug promoter. Knockdown of AhR by siRNA remarkably weakened TCDD-induced binding of AhR to the XRE promoter of slug, thereby suppressed TCDD-induced vimentin. Further experiment showed that TCDD stimulated EGFR phosphorylation did not influence the TGFβ3/Smad signaling; whereas TCDD increased phosphorylation of ERK1/2 and p38 with no effect on activation of JNK. By using varieties of inhibitors, we confirmed that TCDD promoted proliferation and EMT of hFPECs via activation of EGFR/ERK pathway. These data make a novel contribution to the molecular mechanism of cleft palate by TCDD. - Highlights: • TCDD exposure promoted cell proliferation and EMT of hFPECs; • AhR signaling was activated and required for TCDD-induced EMT; • TCDD-mediated EMT of hFPECs involved the activation of EGFR/ERK signaling; • TCDD exposure had no effect on TGFβ3/Smad pathway.

  20. Effect of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD on Hormones of Energy Balance in a TCDD-Sensitive and a TCDD-Resistant Rat Strain

    Directory of Open Access Journals (Sweden)

    Jere Lindén

    2014-08-01

    Full Text Available One of the hallmarks of the acute toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD is a drastically reduced feed intake by an unknown mechanism. To further elucidate this wasting syndrome, we followed the effects of a single large dose (100 μg/kg of TCDD on the serum levels of several energy balance-influencing hormones, clinical chemistry variables, and hepatic aryl hydrocarbon receptor (AHR expression in two rat strains that differ widely in their TCDD sensitivities, for up to 10 days. TCDD affected most of the analytes in sensitive Long-Evans rats, while there were few alterations in the resistant Han/Wistar strain. However, analyses of feed-restricted unexposed Long-Evans rats indicated several of the perturbations to be secondary to energy deficiency. Notable increases in ghrelin and glucagon occurred in TCDD-treated Long-Evans rats alone, which links these hormones to the wasting syndrome. The newly found energy balance regulators, insulin-like growth factor 1 and fibroblast growth factor 21 (FGF-21, appeared to function in concert in body weight loss-induced metabolic state, and FGF-21 was putatively linked to increased lipolysis induced by TCDD. Finally, we demonstrate a reverse set of changes in the AHR protein and mRNA response to TCDD and feed restriction, suggesting that AHR might function also as a physiological regulator, possibly involved in the maintenance of energy balance.

  1. TCDD-inducible poly-ADP-ribose polymerase (TIPARP/PARP7) mono-ADP-ribosylates and co-activates liver X receptors.

    Science.gov (United States)

    Bindesbøll, Christian; Tan, Susanna; Bott, Debbie; Cho, Tiffany; Tamblyn, Laura; MacPherson, Laura; Grønning-Wang, Line; Nebb, Hilde Irene; Matthews, Jason

    2016-04-01

    Members of the poly-ADP-ribose polymerase (PARP) family catalyse the ADP-ribosylation of target proteins and are known to play important roles in many cellular processes, including DNA repair, differentiation and transcription. The majority of PARPs exhibit mono-ADP-ribosyltransferase activity rather than PARP activity; however, little is known about their biological activity. In the present study, we report that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-inducible poly-ADP-ribose polymerase (TIPARP), mono-ADP-ribosylates and positively regulates liver X receptor α (LXRα) and LXRβ activity. Overexpression of TIPARP enhanced LXR-reporter gene activity. TIPARP knockdown or deletion reduced LXR regulated target gene expression levels in HepG2 cells and in Tiparp(-/-)mouse embryonic fibroblasts (MEFs) respectively. Deletion and mutagenesis studies showed that TIPARP's zinc-finger and catalytic domains were required to enhance LXR activity. Protein interaction studies using TIPARP and LXRα/β peptide arrays revealed that LXRs interacted with an N-terminal sequence (a.a. 209-236) of TIPARP, which also overlapped with a putative co-activator domain of TIPARP (a.a. 200-225). Immunofluorescence studies showed that TIPARP and LXRα or LXRβ co-localized in the nucleus.In vitroribosylation assays provided evidence that TIPARP mono-ADP-ribosylated both LXRα and LXRβ. Co-immunoprecipitation (co-IP) studies revealed that ADP-ribosylase macrodomain 1 (MACROD1), but not MACROD2, interacted with LXRs in a TIPARP-dependent manner. This was complemented by reporter gene studies showing that MACROD1, but not MACROD2, prevented the TIPARP-dependent increase in LXR activity. GW3965-dependent increases in hepatic Srebp1 mRNA and protein expression levels were reduced in Tiparp(-/-)mice compared with Tiparp(+/+)mice. Taken together, these data identify a new mechanism of LXR regulation that involves TIPARP, ADP-ribosylation and MACROD1. © 2016 Authors; published by Portland Press

  2. Relationship between murine Ah phenotype and the hepatic metabolism of 2,3,7,8-tetrachlorodibenzo-P-dioxin (TCDD)

    International Nuclear Information System (INIS)

    Shen, E.S.; Olson, J.R.

    1986-01-01

    The Ah receptor has been correlated with the toxic effects of TCDD in C57BL/6J (B6) and DBA/2J (D2) mice. The B6 strain, which has a high affinity cytosolic Ah receptor, is more sensitive to TCDD than the D2 strain, which lacks this receptor. The metabolism of TCDD was studied by incubating 14 C-TCDD (2.2 μM) with hepatocytes from control and TCDD-pretreated B6 and D2 mice. Mice were pretreated with TCDD at doses that maximally induce ethoxyresorufin-O-deethylase (EROD) activity, a measure of Ah locus responsiveness to TCDD (B6, 3μg/kg, ip;D2, 30μg/kg, ip). Similar cytochrome P-450 content was detected in control B6 and D2 hepatocytes, however, TCDD pretreatment increased P-450 content 400% in B6 and 300% in D2 mice. No difference in hepatic EROD activity was found between control B6 and D2 mice (81.7 and 101.7 pmol/min/nmol P-450, respectively), but EROD activity was increased 17-fold in B6 and 10-fold in D2 mice after TCDD administration. The average rate of hepatic TCDD metabolism over two hours was similar in control B6 and D2 mice (1.103 and 0.945 pmol/hr/mg cell protein, respectively), although some qualitative differences in the metabolites were detected by HPLC. TCDD pretreatment produced no quantitative or qualitative changes in TCDD metabolism. These results suggest that the rate of hepatic TCDD metabolism does not correlate with genetic differences at the Ah locus

  3. TCDD alters medial epithelial cell differentiation during palatogenesis

    International Nuclear Information System (INIS)

    Abbott, B.D.; Birnbaum, L.S.

    1989-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widely distributed, persistent environmental contaminant that is teratogenic in mice, where it induces hydronephrosis and cleft palate. The incidence of clefting has been shown to be dose dependent after exposure on either gestation Day (GD) 10 or 12, although the embryo is more susceptible on GD 12. TCDD-exposed palatal shelves meet but do not fuse, and programmed cell death of the medial epithelial cells is inhibited. The mechanism of action through which TCDD alters the program of medial cell development has not been examined in earlier studies, and it is not known whether the mechanism is the same regardless of the dose or developmental stage of exposure. In this study, C57BL/6N mice, a strain sensitive to TCDD, were dosed orally on GD 10 or 12 with 0, 6, 12, 24, or 30 micrograms/kg body wt, in 10 ml corn oil/kg. Embryonic palatal shelves were examined on GD 14, 15, or 16. The degree of palatal closure, epithelial surface morphology, and cellular ultrastructure, the incorporation of [3H]TdR, the expression of EGF receptors, and the binding of 125I-EGF were assessed. After exposure on GD 10 or 12, TCDD altered the differentiation pathway of the medial epithelial cells. The palatal shelves were of normal size and overall morphology, but fusion of the medial epithelia of the opposing shelves did not occur. TCDD prevented programmed cell death of the medial peridermal cells. The expression of EGF receptors by medial cells continued through Day 16 and the receptors were able to bind ligand. The medial cells differentiated into a stratified, squamous, keratinizing epithelium. The shift in phenotype to an oral-like epithelium occurred after exposure on either GD 10 or 12. At the lower dose (6 micrograms/kg), fewer cleft palates were produced, but those shelves which did respond had a fully expressed shift in differentiation

  4. 2,3,7,8-TCDD enhances the sensitivity of mice to concanavalin A immune-mediated liver injury

    Energy Technology Data Exchange (ETDEWEB)

    Fullerton, Aaron M., E-mail: fuller22@msu.edu [Department of Pharmacology and Toxicology, Center for Integrative Toxicology, Michigan State University, 1129 Farm Lane, Room 215, East Lansing, MI 48824 (United States); Roth, Robert A., E-mail: rothr@msu.edu [Department of Pharmacology and Toxicology, Center for Integrative Toxicology, Michigan State University, Food Safety and Toxicology Building, 1129 Farm Lane, Room 221, East Lansing, MI 48824 (United States); Ganey, Patricia E., E-mail: ganey@msu.edu [Department of Pharmacology and Toxicology, Center for Integrative Toxicology, Michigan State University, Food Safety and Toxicology Building, 1129 Farm Lane, Room 214, East Lansing, MI 48824 (United States)

    2013-01-15

    Inflammation plays a major role in immune-mediated liver injury, and exposure to environmental pollutants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter the inflammatory response as well as affect immune cell activity. In this study, we tested the hypothesis that TCDD pretreatment exacerbates hepatotoxicity in a murine model of immune-mediated liver injury induced by concanavalin A (Con A) administration. Mice were pretreated with 30 μg/kg TCDD or vehicle control on day zero and then given either Con A or saline intravenously on day four. Mice treated with TCDD did not develop liver injury; however, TCDD pretreatment increased liver injury resulting from moderate doses of Con A (4–10 mg/kg). TCDD-pretreated mice had altered plasma concentrations of inflammatory cytokines, including interferon gamma (IFNγ), and TCDD/Con A-induced hepatotoxicity was attenuated in IFNγ knockout mice. At various times after treatment, intrahepatic immune cells were isolated, and expression of cell activation markers as well as cytolytic proteins was determined. TCDD pretreatment increased the proportion of activated natural killer T (NKT) cells and the percent of cells expressing Fas ligand (FasL) after Con A administration. In addition FasL knockout mice and mice treated with CD18 antiserum were both protected from TCDD/Con A-induced hepatotoxicity, suggesting a requirement for direct cell–cell interaction between effector immune cells and parenchymal cell targets in the development of liver injury from TCDD/Con A treatment. In summary, exposure to TCDD increased NKT cell activation and exacerbated immune-mediated liver injury induced by Con A through a mechanism involving IFNγ and FasL expression. -- Highlights: ► TCDD pretreatment sensitizes mice to Con A-induced hepatotoxicity. ► TCDD pretreatment increased concentration of IFNγ in plasma after Con A. ► Con A-induced activation of NKT cells was increased by TCDD pretreatment. ► Fas

  5. 2,3,7,8-TCDD enhances the sensitivity of mice to concanavalin A immune-mediated liver injury

    International Nuclear Information System (INIS)

    Fullerton, Aaron M.; Roth, Robert A.; Ganey, Patricia E.

    2013-01-01

    Inflammation plays a major role in immune-mediated liver injury, and exposure to environmental pollutants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been reported to alter the inflammatory response as well as affect immune cell activity. In this study, we tested the hypothesis that TCDD pretreatment exacerbates hepatotoxicity in a murine model of immune-mediated liver injury induced by concanavalin A (Con A) administration. Mice were pretreated with 30 μg/kg TCDD or vehicle control on day zero and then given either Con A or saline intravenously on day four. Mice treated with TCDD did not develop liver injury; however, TCDD pretreatment increased liver injury resulting from moderate doses of Con A (4–10 mg/kg). TCDD-pretreated mice had altered plasma concentrations of inflammatory cytokines, including interferon gamma (IFNγ), and TCDD/Con A-induced hepatotoxicity was attenuated in IFNγ knockout mice. At various times after treatment, intrahepatic immune cells were isolated, and expression of cell activation markers as well as cytolytic proteins was determined. TCDD pretreatment increased the proportion of activated natural killer T (NKT) cells and the percent of cells expressing Fas ligand (FasL) after Con A administration. In addition FasL knockout mice and mice treated with CD18 antiserum were both protected from TCDD/Con A-induced hepatotoxicity, suggesting a requirement for direct cell–cell interaction between effector immune cells and parenchymal cell targets in the development of liver injury from TCDD/Con A treatment. In summary, exposure to TCDD increased NKT cell activation and exacerbated immune-mediated liver injury induced by Con A through a mechanism involving IFNγ and FasL expression. -- Highlights: ► TCDD pretreatment sensitizes mice to Con A-induced hepatotoxicity. ► TCDD pretreatment increased concentration of IFNγ in plasma after Con A. ► Con A-induced activation of NKT cells was increased by TCDD pretreatment. ► Fas

  6. Cellular alterations and enhanced induction of cleft palate after coadministration of retinoic acid and TCDD

    Energy Technology Data Exchange (ETDEWEB)

    Abbott, B.D.; Birnbaum, L.S. (National Institute of Environmental Health Sciences, Research Triangle Park, NC (USA))

    1989-06-15

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and retinoic acid (RA) are both teratogenic in mice. TCDD is a highly toxic, stable environmental contaminant, while RA is a naturally occurring form of vitamin A. Exposure to TCDD induces hydronephrosis and cleft palate, and exposure to RA induces limb defects and cleft palate. Teratology studies previously have shown that the incidence of clefting is higher after exposure to RA + TCDD than would be observed for the same doses of either compound given alone. This study examines the cellular effects which result in cleft palate, after po administration on gestation Day (GD) 10 or 12 of RA + TCDD in corn oil (10 ml/kg total volume). Exposure on GD 10 to 6 micrograms TCDD + 40 mg RA/kg inhibited early growth of the shelves and clefting was due to a failure of shelves to meet and fuse. This effect on mesenchyme was observed in previous studies to occur after exposure on GD 10 to 40 mg/kg RA alone, but not after TCDD alone. After exposure on GD 12 to 6 micrograms TCDD + 80 mg RA/kg, clefting was due to a failure of shelves to fuse after making contact, because the medial cells differentiated into an oral-like epithelium. This response was observed in previous studies to occur after exposure to TCDD alone, but RA alone on GD 12 resulted in differentiation toward nasal-like cells. The interaction between TCDD and RA results in RA-like clefting after exposure on GD 10 and TCDD-like clefting after exposure on GD 12, and this clefting occurs at higher incidences than would occur after the same levels of either agent alone. After exposure on either GD 10 or 12 to RA + TCDD, the programmed cell death of the medial cells does not occur, and these cells continue to express EGF receptors and to bind 125I-EGF. The effects of RA and TCDD may involve modulation of the cells responses to embryonic growth and differentiation factors.

  7. Ancestral TCDD exposure promotes epigenetic transgenerational inheritance of imprinted gene Igf2: Methylation status and DNMTs

    International Nuclear Information System (INIS)

    Ma, Jing; Chen, Xi; Liu, Yanan; Xie, Qunhui; Sun, Yawen; Chen, Jingshan; Leng, Ling; Yan, Huan; Zhao, Bin; Tang, Naijun

    2015-01-01

    Ancestral TCDD exposure could induce epigenetic transgenerational phenotypes, which may be mediated in part by imprinted gene inheritance. The aim of our study was to evaluate the transgenerational effects of ancestral TCDD exposure on the imprinted gene insulin-like growth factor-2 (Igf2) in rat somatic tissue. TCDD was administered daily by oral gavage to groups of F0 pregnant SD rats at dose levels of 0 (control), 200 or 800 ng/kg bw during gestation day 8–14. Animal transgenerational model of ancestral exposure to TCDD was carefully built, avoiding sibling inbreeding. Hepatic Igf2 expression of the TCDD male progeny was decreased concomitantly with hepatic damage and increased activities of serum hepatic enzymes both in the F1 and F3 generation. Imprinted Control Region (ICR) of Igf2 manifested a hypermethylated pattern, whereas methylation status in the Differentially Methylated Region 2 (DMR2) showed a hypomethylated manner in the F1 generation. These epigenetic alterations in these two regions maintained similar trends in the F3 generation. Meanwhile, the expressions of DNA methyltransferases (DNMT1, DNMT3A and DNMT3B) changed in a non-monotonic manner both in the F1 and F3 generation. This study provides evidence that ancestral TCDD exposure may promote epigenetic transgenerational alterations of imprinted gene Igf2 in adult somatic tissue. - Highlights: • Ancestral TCDD exposure induces epigenetic transgenerational inheritance. • Ancestral TCDD exposure affects methylation status in ICR and DMR2 region of Igf2. • DNMTs play a role in TCDD induced epigenetic transgenerational changes of Igf2.

  8. The AhR Ligand, TCDD, Regulates Androgen Receptor Activity Differently in Androgen-Sensitive versus Castration-Resistant Human Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Maryam Ghotbaddini

    2015-07-01

    Full Text Available The reported biological effects of TCDD include induction of drug metabolizing enzymes, wasting syndrome and tumor promotion. TCDD elicits most of its effects through binding the aryl hydrocarbon receptor (AhR. TCDD induced degradation of AhR has been widely reported and requires ubiquitination of the protein. The rapid depletion of AhR following TCDD activation serves as a mechanism to modulate AhR mediated gene induction. In addition to inducing AhR degradation, TCDD has been reported to induce degradation of hormone receptors. The studies reported here, evaluate the effect of TCDD exposure on androgen receptor (AR expression and activity in androgen-sensitive LNCaP and castration-resistant C4-2 prostate cancer cells. Our results show that TCDD exposure does not induce AhR or AR degradation in C4-2 cells. However, both AhR and AR are degraded in LNCaP cells following TCDD exposure. In addition, TCDD enhances AR phosphorylation and induces expression of AR responsive genes in LNCaP cells. Our data reveals that TCDD effect on AR expression and activity differs in androgen-sensitive and castration-resistant prostate cancer cell models.

  9. Effect of TCDD on the fate of epithelial cells isolated from human fetal palatal shelves (hFPECs)

    International Nuclear Information System (INIS)

    Gao, Zhan; Bu, Yongjun; Zhang, Guofu; Liu, Xiaozhuan; Wang, Xugang; Ding, Shibin; Wang, Erhui; Shi, Ruling; Li, Qiaoyun; Fu, Jianhong; Yu, Zengli

    2016-01-01

    Cleft palate is caused by the failure of palatal midline epithelial cells to disintegrate, which is necessary for palatal mesenchymal confluence. Although 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure is linked to cleft palate at a high rate, the mechanism remains to be elucidated. The present study was designed to determine the effects of TCDD on the fate of epithelial cell isolated from human fetal palatal shelves (hFPECs). We demonstrate that TCDD increased cell proliferation and promoted the progression of cells from G1 to S phase as well as increased the number of cells entering the G2/M phase. We found that TCDD has no measurable effect on apoptosis of hFPECs. The protein level assays revealed that TCDD increased cyclin-dependent kinases 4 (cdk4), cyclin D1, cyclin E and p21 (Waf1/Cip1) but not cdk2, bcl-2, cyclin B1 and cyclin A. Furthermore, TCDD activated PI3K/AKT signaling, and the PI3K inhibitor, LY294002, partially abrogated TCDD-induced cell proliferation and gene modulations. TCDD treatment increased CYP1A1 mRNA and protein levels, which indicated the activation of AhR signaling. Knockdown of the AhR with siRNA suppressed TCDD-induced cell proliferation and PI3K/AKT signaling activation. Taken together, these data demonstrated that TCDD is able to promote growth of hFPECs through AhR-dependent activation of the PI3K/AKT pathway, which may account for the underlying mechanism by which TCDD causes a failure of palatal fusion. - Highlights: • TCDD promoted the cell growth with a character of significant accumulation of cells in G2/M. • TCDD treatment induced a various profile of cell cycle regulatory proteins. • PI3K/AKT pathway was involved in TCDD-induced cell proliferation and gene modifications. • AhR knockdown blocked TCDD-induced cell proliferation and PI3K/Akt signaling activation.

  10. GFP transgenic medaka (Oryzias latipes under the inducible cyp1a promoter provide a sensitive and convenient biological indicator for the presence of TCDD and other persistent organic chemicals.

    Directory of Open Access Journals (Sweden)

    Grace Hwee Boon Ng

    Full Text Available Persistent organic pollutants (POPs are resistant to environmental degradation and can cause multitude of health problems. Cytochrome P450 1A (Cyp1a is often up-regulated by POPs through the activation of aryl hydrocarbon receptor (AhR pathway and is thus usually used as a biomarker for xenobiotics exposure. To develop a convenient in vivo tool to monitor xenobiotic contamination in the water, we have established GFP transgenic medaka using the inducible cyp1a promoter, Tg(cyp1a:gfp. Here we tested Tg(cyp1a:gfp medaka at three different stages, prehatching embryos, newly hatched fry and adult with 2,3,7,8-tetrachlorodiebnzo-p-dioxin (TCDD, a dioxin. While GFP induction was observed in all three stages, newly hatched fry were the most sensitive with the lowest observed effective concentration of 0.005 nM or 16.1 ng/L. The highly sensitive organs included the kidney, liver and intestine. With high concentrations of TCDD, several other organs such as the olfactory pit, tail fin, gills, lateral line neuromast cells and blood vessels also showed GFP expression. In addition, Tg(cyp1a:gfp medaka fry also responded to two other AhR agonists, 3-methylcholanthrene and benzo[a]pyrene, for GFP induction, but no significant GFP induction was observed towards several other chemicals tested, indicating the specificity of this transgenic line. The GFP inducibility of Tg(cyp1a:gfp medaka at both fry and adult stages may be useful for development of high-throughput assays as well as online water monitoring system to detect xenobiotic toxicity.

  11. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    International Nuclear Information System (INIS)

    Liu, Qing; Rise, Matthew L.; Spitsbergen, Jan M.; Hori, Tiago S.; Mieritz, Mark; Geis, Steven; McGraw, Joseph E.; Goetz, Giles; Larson, Jeremy; Hutz, Reinhold J.; Carvan, Michael J.

    2013-01-01

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  12. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qing [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States); Rise, Matthew L. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Spitsbergen, Jan M. [Department of Microbiology, Oregon State University, 220 Nash Hall, Corvallis, OR 97331 (United States); Hori, Tiago S. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Mieritz, Mark; Geis, Steven [Wisconsin State Laboratory of Hygiene, 465 Henry Mall, Madison, WI 53706 (United States); McGraw, Joseph E. [School of Pharmacy, Concordia University Wisconsin, 12800 North Lake Shore Drive, Mequon, WI 53097 (United States); Goetz, Giles [School of Aquatic and Fishery Sciences, University of Washington, 1122 Northeast Boat Street, Seattle, WA 98195 (United States); Larson, Jeremy; Hutz, Reinhold J. [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); Carvan, Michael J., E-mail: carvanmj@uwm.edu [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States)

    2013-09-15

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  13. Proteomic analysis of human bladder epithelial cells by 2D blue native SDS-PAGE reveals TCDD-induced alterations of calcium and iron homeostasis possibly mediated by nitric oxide.

    Science.gov (United States)

    Verma, Nisha; Pink, Mario; Petrat, Frank; Rettenmeier, Albert W; Schmitz-Spanke, Simone

    2015-01-02

    A proteomic analysis of the interaction among multiprotein complexes involved in 2,3,7,8-dibenzo-p-dioxin (TCDD)-mediated toxicity in urinary bladder epithelial RT4 cells was performed using two-dimensional blue native SDS-PAGE (2D BN/SDS-PAGE). To enrich the protein complexes, unexposed and TCDD-exposed cells were fractionated. BN/SDS-PAGE of the resulting fractions led to an effective separation of proteins and protein complexes of various origins, including cell membrane, mitochondria, and other intracellular compartments. Major differences between the proteome of control and exposed cells involved the alteration of many calcium-regulated proteins (calmodulin, protein S100-A2, annexin A5, annexin A10, gelsolin isoform b) and iron-regulated proteins (ferritin, heme-binding protein 2, transferrin). On the basis of these findings, the intracellular calcium concentration was determined, revealing a significant increase after 24 h of exposure to TCDD. Moreover, the concentration of the labile iron pool (LIP) was also significantly elevated in TCDD-exposed cells. This increase was strongly inhibited by the calmodulin (CaM) antagonist W-7, which pointed toward a possible interaction between iron and calcium signaling. Because nitric oxide (NO) production was significantly enhanced in TCDD-exposed cells and was also inhibited by W-7, we hypothesize that alterations in calcium and iron homeostasis upon exposure to TCDD may be linked through NO generated by CaM-activated nitric oxide synthase. In our model, we propose that NO produced upon TCDD exposure interacts with the iron centers of iron-regulatory proteins (IRPs) that modulate the alteration of ferritin and transferrin, resulting in an augmented cellular LIP and, hence, increased toxicity.

  14. Tumorigenic Potential of Extracellular Matrix Metalloproteinase Inducer

    Science.gov (United States)

    Zucker, Stanley; Hymowitz, Michelle; Rollo, Ellen E.; Mann, Richard; Conner, Cathleen E.; Cao, Jian; Foda, Hussein D.; Tompkins, David C.; Toole, Bryan P.

    2001-01-01

    Extracellular matrix metalloproteinase inducer (EMMPRIN), a glycoprotein present on the cancer cell plasma membrane, enhances fibroblast synthesis of matrix metalloproteinases (MMPs). The demonstration that peritumoral fibroblasts synthesize most of the MMPs in human tumors rather than the cancer cells themselves has ignited interest in the role of EMMPRIN in tumor dissemination. In this report we have demonstrated a role for EMMPRIN in cancer progression. Human MDA-MB-436 breast cancer cells, which are tumorigenic but slow growing in vivo, were transfected with EMMPRIN cDNA and injected orthotopically into mammary tissue of female NCr nu/nu mice. Green fluorescent protein was used to visualize metastases. In three experiments, breast cancer cell clones transfected with EMMPRIN cDNA were considerably more tumorigenic and invasive than plasmid-transfected cancer cells. Increased gelatinase A and gelatinase B expression (demonstrated by in situ hybridization and gelatin substrate zymography) was demonstrated in EMMPRIN-enhanced tumors. In contrast to de novo breast cancers in humans, human tumors transplanted into mice elicited minimal stromal or inflammatory cell reactions. Based on these experimental studies and our previous demonstration that EMMPRIN is prominently displayed in human cancer tissue, we propose that EMMPRIN plays an important role in cancer progression by increasing synthesis of MMPs. PMID:11395366

  15. Effects of TCDD on the expression of nuclear encoded mitochondrial genes

    International Nuclear Information System (INIS)

    Forgacs, Agnes L.; Burgoon, Lyle D.; Lynn, Scott G.; LaPres, John J.; Zacharewski, Timothy

    2010-01-01

    Generation of mitochondrial reactive oxygen species (ROS) can be perturbed following exposure to environmental chemicals such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Reports indicate that the aryl hydrocarbon receptor (AhR) mediates TCDD-induced sustained hepatic oxidative stress by decreasing hepatic ATP levels and through hyperpolarization of the inner mitochondrial membrane. To further elucidate the effects of TCDD on the mitochondria, high-throughput quantitative real-time PCR (HTP-QRTPCR) was used to evaluate the expression of 90 nuclear genes encoding mitochondrial proteins involved in electron transport, oxidative phosphorylation, uncoupling, and associated chaperones. HTP-QRTPCR analysis of time course (30 μg/kg TCDD at 2, 4, 8, 12, 18, 24, 72, and 168 h) liver samples obtained from orally gavaged immature, ovariectomized C57BL/6 mice identified 54 differentially expressed genes (|fold change| > 1.5 and P-value < 0.1). Of these, 8 exhibited a sigmoidal or exponential dose-response profile (0.03 to 300 μg/kg TCDD) at 4, 24 or 72 h. Dose-responsive genes encoded proteins associated with electron transport chain (ETC) complexes I (NADH dehydrogenase), III (cytochrome c reductase), IV (cytochrome c oxidase), and V (ATP synthase) and could be generally categorized as having proton gradient, ATP synthesis, and chaperone activities. In contrast, transcript levels of ETC complex II, succinate dehydrogenase, remained unchanged. Putative dioxin response elements were computationally found in the promoter regions of all 8 dose-responsive genes. This high-throughput approach suggests that TCDD alters the expression of genes associated with mitochondrial function which may contribute to TCDD-elicited mitochondrial toxicity.

  16. Perinatal TCDD exposure alters developmental neuroendocrine system.

    Science.gov (United States)

    Ahmed, R G

    2011-06-01

    This study tested whether maternal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) may disrupt the development of neuroendocrine system of their offspring during the perinatal period. TCDD (0.2 or 0.4 μg/kg body weight) was orally administered to pregnant rats from gestation day (GD) 1 to lactation day (LD) 30. Potential effects on neuroendocrine function were evaluated by measuring serum thyroid hormone levels in pregnant rats and their offspring and measuring some biochemical parameters in cerebellum of these offspring on GD 16 and 19, and LD 10, 20, and 30. In both treated groups, a decrease in serum thyroxine (T4), triiodothyronine (T3) and increase in thyrotropin (TSH) levels were noticed during the tested days in dams and offspring, as well as GH levels were decreased in offspring with respect to control group. In cerebellum of control offspring, the levels of monoamines, γ-aminobutyric acid (GABA) and acetylcholinesterase (AchE) were found to be increased from GD 16 to LD 30. The hypothyroid conditions due to both maternal administrations of TCDD produced inhibitory effects on monoamines and AchE, and stimulatory actions on GABA in cerebellum of offspring. These alterations were dose and age dependent. Overall, these results suggest that TCDD may act as neuroendocrine disruptor. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  17. Sex-related differences in murine hepatic transcriptional and proteomic responses to TCDD

    International Nuclear Information System (INIS)

    Prokopec, Stephenie D.; Watson, John D.; Lee, Jamie; Pohjanvirta, Raimo; Boutros, Paul C.

    2015-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant that produces myriad toxicities in most mammals. In rodents alone, there is a huge divergence in the toxicological response across species, as well as among different strains within a species. But there are also significant differences between males and females animals of a single strain. These differences are inconsistent across model systems: the severity of toxicity is greater in female rats than males, while male mice and guinea pigs are more sensitive than females. Because the specific events that underlie this difference remain unclear, we characterized the hepatic transcriptional response of adult male and female C57BL/6 mice to 500 μg/kg TCDD at multiple time-points. The transcriptional profile diverged significantly between the sexes. Female mice demonstrated a large number of altered transcripts as early as 6 h following treatment, suggesting a large primary response. Conversely, male animals showed the greatest TCDD-mediated response 144 h following exposure, potentially implicating significant secondary responses. Nr1i3 was statistically significantly induced at all time-points in the sensitive male animals. This mRNA encodes the constitutive androstane receptor (CAR), a transcription factor involved in the regulation of xenobiotic metabolism, lipid metabolism, cell cycle and apoptosis. Surprisingly though, changes at the protein level (aside from the positive control, CYP1A1) were modest, with only FMO3 showing clear induction, and no genes with sex-differences. Thus, while male and female mice show transcriptional differences in their response to TCDD, their association with TCDD-induced toxicities remains unclear. - Highlights: • Differences exist between the toxicity phenotypes to TCDD in male and female mice. • TCDD-mediated transcriptomic differences were identified between the sexes. • Resistant female mice displayed a large, early-onset, transcriptomic response.

  18. Sex-related differences in murine hepatic transcriptional and proteomic responses to TCDD

    Energy Technology Data Exchange (ETDEWEB)

    Prokopec, Stephenie D.; Watson, John D. [Informatics and Bio-computing Program, Ontario Institute for Cancer Research, Toronto (Canada); Lee, Jamie [Informatics and Bio-computing Program, Ontario Institute for Cancer Research, Toronto (Canada); Department of Pharmacology & Toxicology, University of Toronto, Toronto (Canada); Pohjanvirta, Raimo [Laboratory of Toxicology, National Institute for Health and Welfare, Kuopio Finland (Finland); Department of Food Hygiene and Environmental Health, University of Helsinki, Helsinki (Finland); Boutros, Paul C., E-mail: Paul.Boutros@oicr.on.ca [Informatics and Bio-computing Program, Ontario Institute for Cancer Research, Toronto (Canada); Department of Pharmacology & Toxicology, University of Toronto, Toronto (Canada); Department of Medical Biophysics, University of Toronto, Toronto (Canada)

    2015-04-15

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant that produces myriad toxicities in most mammals. In rodents alone, there is a huge divergence in the toxicological response across species, as well as among different strains within a species. But there are also significant differences between males and females animals of a single strain. These differences are inconsistent across model systems: the severity of toxicity is greater in female rats than males, while male mice and guinea pigs are more sensitive than females. Because the specific events that underlie this difference remain unclear, we characterized the hepatic transcriptional response of adult male and female C57BL/6 mice to 500 μg/kg TCDD at multiple time-points. The transcriptional profile diverged significantly between the sexes. Female mice demonstrated a large number of altered transcripts as early as 6 h following treatment, suggesting a large primary response. Conversely, male animals showed the greatest TCDD-mediated response 144 h following exposure, potentially implicating significant secondary responses. Nr1i3 was statistically significantly induced at all time-points in the sensitive male animals. This mRNA encodes the constitutive androstane receptor (CAR), a transcription factor involved in the regulation of xenobiotic metabolism, lipid metabolism, cell cycle and apoptosis. Surprisingly though, changes at the protein level (aside from the positive control, CYP1A1) were modest, with only FMO3 showing clear induction, and no genes with sex-differences. Thus, while male and female mice show transcriptional differences in their response to TCDD, their association with TCDD-induced toxicities remains unclear. - Highlights: • Differences exist between the toxicity phenotypes to TCDD in male and female mice. • TCDD-mediated transcriptomic differences were identified between the sexes. • Resistant female mice displayed a large, early-onset, transcriptomic response.

  19. Combined 17β-Estradiol with TCDD Promotes M2 Polarization of Macrophages in the Endometriotic Milieu with Aid of the Interaction between Endometrial Stromal Cells and Macrophages.

    Directory of Open Access Journals (Sweden)

    Yun Wang

    Full Text Available The goal of this study is to elucidate the effects of 17β-estradiol and TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin on macrophage phenotypes in the endometriotic milieu. Co-culture of endometrial stromal cells (ESCs and U937 cells (macrophage cell line was performed to simulate the endometriotic milieu and to determine the effects of 17β-estradiol and/or TCDD on IL10, IL12 production and HLA-DR, CD86 expression by U937 macrophages. We found that combining 17β-estradiol with TCDD has a synergistic effect on inducing M2 activation when macrophages are co-cultured with ESCs. Moreover, the combination of 17β-estradiol and TCDD significantly enhanced STAT3 and P38 phosphorylation in macrophages. Differentiation of M2 macrophages induced by 17β-estradiol and TCDD were effectively abrogated by STAT3 and P38MAPK inhibitors, but not by ERK1/2 and JNK inhibitors. In conclusion, 17β-estradiol and TCDD in the ectopic milieu may lead to the development of endometriosis by inducing M2 polarization of macrophages through activation of the STAT3 and P38MAPK pathways.

  20. TCDD adsorbed on silica as a model for TCDD contaminated soils: Evidence for suppression of humoral immunity in mice.

    Science.gov (United States)

    Kaplan, Barbara L F; Crawford, Robert B; Kovalova, Natalia; Arencibia, Amaya; Kim, Seong Su; Pinnavaia, Thomas J; Boyd, Stephen A; Teppen, Brian J; Kaminski, Norbert E

    2011-04-11

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), the prototypical aryl hydrocarbon receptor (AhR) ligand, exhibits immune suppression in vivo and in vitro. Suppression of primary humoral immune responses in particular has been well characterized as one of the most sensitive functional immune endpoints in animals treated with TCDD. Previous studies have used purified TCDD to elucidate the mechanisms by which TCDD and dioxin-like compounds (DLC) impair IgM production by B cells, but did not represent the route by which animals and humans are likely to be exposed environmentally. In the studies reported here, mice were treated with TCDD adsorbed onto a well-defined synthetic silica phase of known purity and physical properties, followed by sensitization with sheep erythrocytes to initiate a humoral immune response. We found that surfactant-templated mesoporous forms of amorphous silica provided an ideal combination of purity, dispersibility and textural properties for immobilizing TCDD. TCDD-adsorbed silica distributed to the spleen and liver after oral administration as assessed by induction of cyp1a1 gene expression. Most notably, TCDD delivered in the adsorbed state on amorphous silica and as a solute in corn oil (CO) produced similar suppression of the anti-sheep red blood cell immunoglobulin M antibody forming cell (sRBC IgM AFC) response at equivalent doses of TCDD. These results suggest that TCDD immobilized on silicate particles found in soils distributes to the spleen and suppresses humoral immunity. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. Induction of lipid peroxidation by hexachlorocyclohexane, dieldrin, TCDD, carbon tetrachloride, and hexachlorobenzene in rats

    Energy Technology Data Exchange (ETDEWEB)

    Goel, M.R.; Shara, M.A.; Stohs, S.J.

    1988-02-01

    Hexachlorobenzene (HCB), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), hexachlorocyclohexane (HCCH) and dieldrin are all halogenated lipophilic environmental contaminants. A common biologic property of these compounds is their ability to induce hepatic microsomal drug metabolizing enzymes. Furthermore, exposure of laboratory animals to these xenobiotics elicits a number of similar effects including porphyria, hypothyroidism, a wasting syndrome and lethality. Perturbation of membrane lipids and lipid peroxidation may be responsible for at least part of the toxic effects of HCCH. TCDD has been shown to induce lipid peroxidation in hepatic and extrahepatic tissues. Based on the similar toxic manifestations of HCB, HCCH, TCDD and dieldrin, the authors have examined the effects of these xenobiotics on hepatic lipid peroxidation following an acutely toxic dose. Lipid peroxidation was assessed by determining the content of thiobarbituric acid reactive substance (TBARS) in the liver, employing malondialdehyde as the standard. Animals were also treated with carbon tetrachloride, a well know inducer of lipid peroxidation, as a positive control. Furthermore, the ability of these xenobiotics to inhibit selenium dependent glutathione peroxidase (GSHPX) activity was determined.

  2. An enhanced postnatal autoimmune profile in 24 week-old C57BL/6 mice developmentally exposed to TCDD

    International Nuclear Information System (INIS)

    Mustafa, A.; Holladay, S.D.; Goff, M.; Witonsky, S.G.; Kerr, R.; Reilly, C.M.; Sponenberg, D.P.; Gogal, R.M.

    2008-01-01

    Developmental exposure of mice to the environmental contaminant and AhR agonist, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), causes persistent postnatal suppression of T cell-mediated immune responses. The extent to which prenatal TCDD may induce or exacerbate postnatal autoimmune disease remains unknown. In the present study, time-pregnant high affinity AhR C57BL/6 mice received a single oral administration of 0, 2.5, or 5 μg/kg TCDD on gestation day (gd) 12. Offspring of these mice (n = 5/gender/treatment) were evaluated at 24 weeks-of-age and showed considerable immune dysregulation that was often gender-specific. Decreased thymic weight and percentages of CD4 + CD8 + thymocytes, and increased CD4 + CD8 - thymocytes, were present in the female but not male offspring. Males but not females showed decreased CD4 - CD8 + T cells, and increased Vβ3 + and Vβ17a + T cells, in the spleen. Males but not females also showed increased percentages of bone marrow CD24 - B220 + B cell progenitors. Antibody titers to dsDNA, ssDNA and cardiolipin displayed increasing trends in both male and female mice, reaching significance for anti-dsDNA in both genders and for ssDNA in males at 5 μg/kg TCDD. Immunofluorescent staining of IgG and C3 deposition in kidney glomeruli increased in both genders of prenatal TCDD-exposed mice, suggestive of early stages of autoimmune glomerulonephritis. Collectively, these results show that exposure to TCDD during immune system development causes persistent humoral immune dysregulation as well as altered cell-mediated responses, and induces an adult profile of changes suggestive of increased risk for autoimmune disease

  3. TCDD disrupts posterior palatogenesis and causes cleft palate.

    Science.gov (United States)

    Yamada, Tomohiro; Hirata, Azumi; Sasabe, Eri; Yoshimura, Tomohide; Ohno, Seiji; Kitamura, Naoya; Yamamoto, Tetsuya

    2014-01-01

    Dioxins (e.g. 2,3,7,8-tetrachlorodibenzo-p-dioxin; TCDD) cause cleft palate at a high rate. A post-fusional split may contribute to the pathogenesis, and tissue fragility may be a concern. The objective of this study was to investigate the effects of TCDD on the palatal epithelium, bone and muscle, which contribute to tissue integrity. ICR mice (10-12 weeks old) were used. TCDD was administered on E12.5 at 40 mg/kg. Immunohistochemical staining for AhR, ER-α, laminin, collagen IV, osteopontin, Runx2, MyoD, and desmin were performed. Furthermore, western blot analysis for osteopontin, Runx2, MyoD, and desmin were performed to evaluate protein expression in the palatal tissue. Immunohistologically, there was little difference in the collagen IV and laminin localization in the palatal epithelium between control versus TCDD-treated mice. Runx2 and osteopontin immunoreactivity decreased in the TCDD-treated palatal bone, and MyoD and desmin decreased in the TCDD-treated palatal muscle. AhR and ER-α immunoreactivity were localized to the normal palatal bone, but ER-α was diminished in the TCDD-treated palate. On western blot analysis, Runx2, MyoD, and desmin were all downregulated in the TCDD-treated palate. TCDD may suppress palatal osteogenesis and myogenesis via AhR, and cause cleft palates via a post-fusional split mechanism, in addition to a failure of palatal fusion. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  4. Autologous Matrix-Induced Chondrogenesis in the Knee: A Review.

    Science.gov (United States)

    Lee, Yee Han Dave; Suzer, Ferzan; Thermann, Hajo

    2014-07-01

    Autologous matrix-induced chondrogenesis (AMIC) is a 1-step cartilage restoration technique that combines microfracture with the use of an exogenous scaffold. This matrix covers and mechanically stabilizes the clot. There have been an increasing number of studies performed related to the AMIC technique and an update of its use and results is warranted. Using the PubMed database, a literature search was performed using the terms "AMIC" or "Autologous Matrix Induced Chondrogenesis." A total of 19 basic science and clinical articles were identified. Ten studies that were published on the use of AMIC for knee chondral defects were identified and the results of 219 patients were analyzed. The improvements in Knee Injury and Osteoarthritis Outcome Score, International Knee Documentation Committee Subjective, Lysholm and Tegner scores at 2 years were comparable to the published results from autologous chondrocyte implantation (ACI) and matrix ACI techniques for cartilage repair. Our systematic review of the current state of the AMIC technique suggests that it is a promising 1-stage cartilage repair technique. The short-term clinical outcomes and magnetic resonance imaging results are comparable to other cell-based methods. Further studies with AMIC in randomized studies versus other repair techniques such as ACI are needed in the future.

  5. Curcumin, myrecen and cineol modulate the percentage of lymphocyte subsets altered by 2,3,7, 8-tetracholorodibenzo-p-dioxins (TCDD) in rats.

    Science.gov (United States)

    Ciftci, Osman; Tanyildizi, Sadettin; Godekmerdan, Ahmet

    2011-12-01

    The aim of this study was to investigate the toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a persistent environmental pollutant, on the percentage of T-cell subsets and B-lymphocyte and effectiveness of curcumin, β-myrcene (myrcene) and 1,8-cineole (cineol) on this toxicity in rats. Rats (n = 112) were divided randomly into 8 equal groups. One group was kept as control and given corn oil as carrier. TCDD was orally administered at the dose of 2 µg/kg/week. Curcumin, myrcene and cineol were orally administered by gavages at the doses of 100, 200 and 100 mg/kg/day, respectively, dissolved in corn oil with and without TCDD. The blood samples were taken from half of the rats on day 30 and from the rest on day 60 for the determination of lymphocyte subsets (CD3(+), CD4(+), CD8(+), CD161(+), CD45RA, CD4(+)CD25(+) and total lymphocyte). The results indicated that although TCDD significantly (p cineol significantly decreased CD8(+) cells levels but increased CD3(+), CD4(+), CD161(+), CD45RA, CD4(+)CD25(+) and total lymphocyte cells populations. The beneficial effects of curcumin, myrcene and cineol and the toxic effects of TCDD were increased at day 60 compared to day 30. In conclusion, curcumin, myrcene and cineol showed immunomodulatory effects and eliminated TCDD-induced immune suppressive effects in rats.

  6. COMPUTATION MODELING OF TCDD DISRUPTION OF B CELL TERMINAL DIFFERENTIATION

    Science.gov (United States)

    In this study, we established a computational model describing the molecular circuit underlying B cell terminal differentiation and how TCDD may affect this process by impinging upon various molecular targets.

  7. Severe 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) intoxication: kinetics and trials to enhance elimination in two patients

    Energy Technology Data Exchange (ETDEWEB)

    Geusau, A. [Dept. of Dermatology, Univ. of Vienna, Vienna (Austria); Schmaldienst, S.; Derfler, K. [Dept. of Internal Medicine, Univ. of Vienna, Vienna (Austria); Paepke, O. [ERGO Forschungsgesellschaft mbH, Hamburg (Germany); Abraham, K. [Dept. of Pediatric Pneumology and Immunology, Children' s Hospital, Charite, Humboldt Univ., Berlin (Germany)

    2002-06-01

    In spring 1998, two women were diagnosed with severe 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) intoxication. Over the following 3 years, TCDD levels were monitored under various attempts to enhance its elimination, and the half-lives were evaluated. Olestra, a non-digestible, non-absorbable dietary fat substitute, was continuously administered to the patients either as pure substance or in potato-chips. Additionally, in the more severely contaminated patient, we studied whether low-density lipoprotein (LDL)-apheresis, an extracorporeal means of blood lipid elimination, was effective in reducing the TCDD body burden. The blood concentrations initially measured in spring 1998 were 144,000 pg/g blood fat in patient 1 and 26,000 pg/g in patient 2, the highest levels ever measured in adults. In March 2001, concentrations in blood fat were 35,900 and 9,500 pg/g, corresponding to overall elimination half-lives of 560 days (1.5 years) in patient 1 and 1050 days (2.9 years) in patient 2, which are considerably shorter than median values of 7-9 years reported for background and moderate exposure levels. Calculations of the TCDD half-lives and measurements of TCDD elimination via different routes allowed the calculation of an unidentified route of elimination, representing 78 and 62% of the overall elimination in patient 1 and 2, respectively, probably due to an induced hepatic metabolism caused by the high TCDD exposure. As previously reported, administration of olestra was found to be effective in increasing the fecal excretion of TCDD. Due to the short half-lives in our patients, the effect of olestra on the overall elimination was relatively small, but is expected to be much greater for 'normal' half-lives. LDL-apheresis was shown to eliminate TCDD, corresponding to the eliminated blood fat. When employed twice a week, the amount of TCDD excreted by this method was comparable to fecal excretion. In view of costs and time involved, LDL-apheresis does not seem to

  8. Expressions of matrix metalloproteinase-2 and extracellular matrix metalloproteinase inducer in retinoblastoma

    Directory of Open Access Journals (Sweden)

    Yu-Hong Cheng

    2015-07-01

    Full Text Available AIM: To investigate expressions of matrix metalloproteinase-2(MMP-2and extracellular matrix metalloproteinase inducer(EMMPRINin retinoblastoma(Rband the relationships between MMP-2, EMMPRIN and tumor development.METHODS:Immunohistochemical technique was used to detect expressions of MMP-2 and EMMPRIN in 39 cases of paraffin embedded Rb samples. Quantitative analysis of expressions of MMP-2 and EMMPRIN were assessed by measuring the mean gray scale of Rb tissue with LEICA IM50 Color Pathologic Analysis System. The differences of expressions of MMP-2 and EMMPRIN in each clinical and pathological stage were statistically analyzed, and the same step was also undertaken to study the relationship between Rb with MMP-2 positive expression and that with EMMPRIN positive expression.RESULTS: The positive expression rate of MMP-2 was 90%(Gray value: 109.64±14.52; 35/39, and that of EMMPRIN was 85%(Gray value: 108.01±13.60; 33/39. The expressions of MMP-2 and EMMPRIN were significantly higher in tumors of glaucomatous stage(Gray value: 108.21±11.47 and 107.56±14.32than those in intraocular stage(Gray value: 121.13±11.32 and 119.34±12.66; PPPPPPCONCLUSION: The positive expression levels of MMP-2 and EMMPRIN may correlate with tumor infiltration and metastasis.

  9. Studies on the mechanism of rapid activation of protein tyrosine phosphorylation activities, particularly c-Src kinase, by TCDD in MCF10A.

    Science.gov (United States)

    Mazina, Olga; Park, Sujin; Sano, Hiromi; Wong, Patrick; Matsumura, Fumio

    2004-01-01

    While the process of the Ah receptor activation leading to cytochrome P450 induction has been well studied, the mechanism and the process through which the Ah receptor activates tyrosine kinases, within a few minutes of its ligand binding, is not known. Previously, it was reported by Tannheimer et al. (Carcinogenesis 1998; 19:1291-1297) that TCDD causes rapid induction of tyrosine phosphorylation activities in the MCF10A human mammary epithelial cell line. To study the mechanistic aspect of this phenomenon, particularly that occurs within a few minutes after administration, we first studied the effect of insulin on MCF10A under serum free conditions with added EGF. The addition of insulin induced a rapid (5 min) tyrosine phosphorylation on several 160-190 kDa proteins which was followed by significant dephosphorylation activities on these proteins by 15 min. TCDD increased the rate of tyrosine phosphorylation on those proteins but at 15 min, the level of phosphorylation was still high. When insulin and TCDD were added together, the ability of insulin to induce de-phosphorylation by 15 min disappeared. Such an action of TCDD was accompanied by an increase in the titer of the activated form of Src kinase (i.e. c-Src protein with 418 tyrosine phosphorylation), and a concomitant decrease in the level of 529 tyrosine phosphorylated form (an inactivated form). The TCDD-induced activation of c-Src could be blocked by pretreated MCF10A cells with antisense oligonucleotides against c-src or with a specific inhibitor of Src kinase, PP-2. These results support the conclusion that c-Src kinase is at least one of the earliest and the most upstream components of toxic signaling of the Ah-receptor activated by TCDD through the post-transcriptional process.

  10. Effects of in ovo 2,3,7,8-TCDD exposure on hepatic ethoxyresorufin O-deethylase (EROD) induction and growth-related parameters in avian species

    Energy Technology Data Exchange (ETDEWEB)

    Janz, D.M.; Bellward, G.D. [Univ. of British Columbia, Vancouver, British Columbia (Canada). Faculty of Pharmaceutical Sciences

    1994-12-31

    The effects of early in ovo TCDD exposure on CYP1A1 induction and indices of growth were determined in domestic chicken (Gallus gallus) and pigeon (Columba livia) hatchlings. TCDD (in corn oil) was injected into the air sac of eggs on embryonic day 4 (E4) (chickens, 0.1 {mu}g/kg egg; pigeons, 1.0 {mu}g/kg egg), and on E14 (pigeons, 3.0 {mu}g/kg egg). In chickens, hepatic EROD was induced 13, 15, 34, and 43-fold above control activities on E19, day of hatch (DO), day 2 after hatch (D2), and D4, respectively. Plasma thyroid hormone (T{sub 3} T{sub 4}) concentrations, which are known to peak during the perinatal period in chickens, were not affected by TCDD treatment when measured on E17, E19, D0, D2, and D4. In pigeons injected on E4, EROD was induced 15 and 6-fold on D0 and D7, respectively. There were significant decreases in yolk-free body weight, crown-rump, tibia, culmen, and wing lengths, and an elevated liver to body weight ratio (LSI) in TCDD-treated pigeons raised to D7 (p < 0.01). In pigeons injected on E14 (3{mu}g/kg), EROD was induced 14 and 10-fold on D0 and D7, respectively. Crown-rump and culmen lengths were decreased (p < 0.05) and LSI was increased (p < 0.01) on D0. There were significant decreases in all morphological parameters, and an increased LSI on D7 (p < 0.01) in TCDD-treated birds. These techniques will be used in further studies to investigate possible mechanisms of TCDD embryotoxicity in wild avian species, such as the great blue heron (Ardea herodias).

  11. Estrogenic Activity of Coumestrol, DDT, and TCDD in Human Cervical Cancer Cells

    Directory of Open Access Journals (Sweden)

    Kenneth Ndebele

    2010-05-01

    Full Text Available Endogenous estrogens have dramatic and differential effects on classical endocrine organ and proliferation. Xenoestrogens are environmental estrogens that have endocrine impact, acting as both estrogen agonists and antagonists, but whose effects are not well characterized. In this investigation we sought to delineate effects of xenoestrogens. Using human cervical cancer cells (HeLa cells as a model, the effects of representative xenoestrogens (Coumestrol-a phytoestrogen, tetrachlorodioxin (TCDD-a herbicide and DDT-a pesticide on proliferation, cell cycle, and apoptosis were examined. These xenoestrogens and estrogen inhibited the proliferation of Hela cells in a dose dependent manner from 20 to 120 nM suggesting, that 17-β-estrtadiol and xenoestrogens induced cytotoxic effects. Coumestrol produced accumulation of HeLa cells in G2/M phase, and subsequently induced apoptosis. Similar effects were observed in estrogen treated cells. These changes were associated with suppressed bcl-2 protein and augmented Cyclins A and D proteins. DDT and TCDD exposure did not induce apoptosis. These preliminary data taken together, suggest that xenoestrogens have direct, compound-specific effects on HeLa cells. This study further enhances our understanding of environmental modulation of cervical cancer.

  12. UV-tunable laser induced phototransformations of matrix isolated anethole.

    Science.gov (United States)

    Krupa, Justyna; Wierzejewska, Maria; Nunes, Cláudio M; Fausto, Rui

    2014-03-14

    A matrix isolation study of the infrared spectra and structure of anethole (1-methoxy-4-(1-propenyl)benzene) has been carried out, showing the presence of two E conformers (AE1, AE2) of the molecule in the as-deposited matrices. Irradiation using ultraviolet-tunable laser light at 308-307 nm induced conformationally selective phototransformations of these forms into two less stable Z conformers (AZ1, AZ2). The back reactions were also detected upon irradiation at 301 nm. On the whole, the obtained results allow for full assignment of the infrared spectra of all the four experimentally observed anethole isomers and showed that the narrowband UV-induced E-Z photoisomerization is an efficient and selective way to interconvert the two isomers of anethole into each other, with conformational discrimination. Photolysis of anethole was observed as well, with initial methoxyl O-C bond cleavage and formation of CH3 and p-propenylphenoxy (AR) radicals, followed by radical recombination to form 2-methyl-4-propenyl-2,4-cyclohexadienone, which subsequently undergoes ring-opening generating several conformers of long-chain conjugated ketenes. Interpretation of the experimental observations was supported by density functional theory (B3LYP and B2PLYD) calculations.

  13. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) alters the mRNA expression of critical genes associated with cholesterol metabolism, bile acid biosynthesis, and bile transport in rat liver: A microarray study

    International Nuclear Information System (INIS)

    Fletcher, Nick; Wahlstroem, David; Lundberg, Rebecca; Nilsson, Charlotte B.; Nilsson, Kerstin C.; Stockling, Kenneth; Hellmold, Heike; Hakansson, Helen

    2005-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent hepatotoxin that exerts its toxicity through binding to the aryl hydrocarbon receptor (AhR) and the subsequent induction or repression of gene transcription. In order to further identify novel genes and pathways that may be associated with TCDD-induced hepatotoxicity, we investigated gene changes in rat liver following exposure to single oral doses of TCDD. Male Sprague-Dawley rats were administered single doses of 0.4 μg/kg bw or 40 μg/kg bw TCDD and killed at 6 h, 24 h, or 7 days, for global analyses of gene expression. In general, low-dose TCDD exposure resulted in greater than 2-fold induction of genes coding for a battery of phase I and phase II metabolizing enzymes including CYP1A1, CYP1A2, NADPH quinone oxidoreductase, UGT1A6/7, and metallothionein 1. However, 0.4 μg/kg bw TCDD also altered the expression of Gadd45a and Cyclin D1, suggesting that even low-dose TCDD exposure can alter the expression of genes indicative of cellular stress or DNA damage and associated with cell cycle control. At the high-dose, widespread changes were observed for genes encoding cellular signaling proteins, cellular adhesion, cytoskeletal and membrane transport proteins as well as transcripts coding for lipid, carbohydrate and nitrogen metabolism. In addition, decreased expression of cytochrome P450 7A1, short heterodimer partner (SHP; gene designation nr0b2), farnesyl X receptor (FXR), Ntcp, and Slc21a5 (oatp2) were observed and confirmed by RT-PCR analyses in independent rat liver samples. Altered expression of these genes implies major deregulation of cholesterol metabolism and bile acid synthesis and transport. We suggest that these early and novel changes have the potential to contribute significantly to TCDD induced hepatotoxicity and hypercholesterolemia

  14. Focal Cerebral Ischemia Induces Active Proteases That Degrade Microvascular Matrix

    Science.gov (United States)

    Fukuda, Shunichi; Fini, Catherine A.; Mabuchi, Takuma; Koziol, James A.; Eggleston, Leonard L.; del Zoppo, Gregory J.

    2010-01-01

    Background and Purpose Focal cerebral ischemia causes microvessel matrix degradation and generates proteases known to degrade this matrix. However, proof that the proteases generated do indeed degrade vascular matrix is lacking. Here we demonstrate that active proteases derived from ischemic tissue after middle cerebral artery occlusion (MCAO) and transferred to normal tissue can degrade vascular matrix. Methods In an ex vivo bioassay, the effects of supernatants from ischemic and normal basal ganglia of nonhuman primates, proteases, and control buffer on the immunoreactivity of vascular matrix constituents in normal brain tissue sections were quantified. Protease families were identified with specific inhibitors. Results Plasmin, active matrix metalloproteinase (MMP)-2, and active MMP-9 significantly reduced microvessel-associated collagen, laminin, and heparan sulfate proteoglycans (HSPG). The vascular HSPG perlecan was more sensitive than collagen or laminin in the bioassay and in the ischemic core 2 hours after MCAO. Two-hour and 7-day ischemic tissue samples significantly degraded matrix perlecan and collagen. Inhibitor studies confirmed that while active MMPs were generated, active cysteine proteases significantly degraded microvessel perlecan. The cysteine proteases cathepsins B and L were generated in the microvasculature and adjacent neurons or glial cells 2 hours after MCAO and decreased perlecan in the bioassay. Conclusions This is the first direct evidence that active proteases are generated in ischemic cerebral tissues that are acutely responsible for vascular matrix degradation. Degradation of vascular perlecan, the most sensitive matrix component thus far identified, may be due to cathepsins B and L, generated very rapidly after MCAO. PMID:15001799

  15. Coumestrol, Bisphenol-A, DDT, and TCDD Modulation of Interleukin-2 Expression in Activated CD+4 Jurkat T Cells

    Directory of Open Access Journals (Sweden)

    Robert W. McMurray

    2004-02-01

    Full Text Available Endogenous estrogens are known to modulate several components of immune response, including interleukin-2 (IL-2 production. IL-2 is a cytokine that plays an important role in adaptive immune responses. These responses may be modulated by xenoestrogens such as coumestrol, bisphenol A (BPA, DDT, and TCDD. In this research, we examined the effects and potential mechanisms of action of these estrogenic compounds on IL-2 production in activated CD4+ Jurkat T cells. IL-2 production was analyzed by ELISA and Western Blot. At the transcriptional level, protein expression was examined by RT-PCR. Coumestrol, DDT and TCDD (but not BPA significantly suppressed IL-2 production in activated CD4+ Jurkat T cells, at the transcriptional and translational levels. The transcriptional suppression of IL-2 was associated with decreased protein levels of NF-κβ, an important IL-2 positive transcription factor, without affecting the expression of Iκ−Βα protein expression, an important inhibitor of NF-κβ nuclear translocation. Although the direct mechanisms of xenoestrogens modulation of the immune system remain to be elucidated, coumestrol-, DDT- and TCDD-induced suppression of IL-2 may have ramifications for our understanding of the impact of xenoestrogens on health and disease.

  16. Diadenosine tetraphosphate (AP{sub 4}A) levels in muscle tissue as a potential biomarker of PCB and TCDD exposure

    Energy Technology Data Exchange (ETDEWEB)

    Nordone, A. [Consultox Ltd., Damariscotta, ME (United States)]|[Clemson Univ., SC (United States). Dept. of Environmental Toxicology; Grant, T.; Saranko, C.; Pivorun, E. [Clemson Univ., SC (United States). Dept. of Biological Sciences

    1995-12-31

    During the past two decades a group of purine nucleotides, the diadenosine polyphosphates, have gained increasing attention. One of these compounds, diadenosine tetraphosphate (AP{sub 4}A), has been demonstrated to modulate a variety of cellular events, including intracellular signaling during adaptive responses to cellular stress. The authors have recently demonstrated that changes in AP{sub 4}A levels in venous and arterial blood are related to periods of major trauma during corrective spinal surgery. Using Deermice (Peromyscus maniculatus) they investigated whether changes in the concentration of AP{sub 4}A in muscle tissue could be used as a biomarker of chemically induced stress. Using intraperitoneal administration, animals were exposed to either a mixture of PCB congeners (Aroclor 1254), a coplanar PCB (PCB 169), a noncoplanar PCB (PCB 153) or TCDD for a period of 11 days. The coplanar PCB and TCDD decreased AP{sub 4}A concentrations in dose-dependent manner, whereas the noncoplanar PCB increased concentrations in a dose-dependent manner. Aroclor 1254 reduced AP{sub 4}A concentration to a similar level at all doses. These results indicate that PCBs and TCDD modulate AP{sub 4}A concentrations in muscle tissue in a manner that is both dose and structure dependent. It is possible that AP{sub 4}A could be used as a marker of the level of exposure to PCBs and dioxin and as an indicator of the congeners involved.

  17. Correlation between expression of extracellular matrix metalloproteinase inducer and matrix metalloproteinase-2 and cervical lymph node metastasis of nasopharyngeal carcinoma.

    Science.gov (United States)

    Huang, Tian; Chen, Mao-Huai; Wu, Ming-Yao; Wu, Xian-Ying

    2013-03-01

    We evaluated the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase-2 (MMP-2) in nasopharyngeal carcinoma (NPC) and studied their relationship with cervical lymph node metastasis. Immunohistochemical staining was used to detect the expression of EMMPRIN and MMP-2 in specimens from patients with chronic nasopharyngitis (CN), nonmetastastic NPC (NM-NPC), and lymph node-metastatic NPC (LNM-NPC). The rates of positive EMMPRIN expression in CN, NM-NPC, and LNM-NPC were 13.3%, 30.0%, and 66.7%, respectively. Significant differences were found between the rates in CN and LNM-NPC (p correlated (rs = 0.466; p <0.01). Nasopharyngeal carcinoma cells may attain enhanced metastastic capability through the expression of MMP-2 induced by EMMPRIN.

  18. ANALYSIS OF 2,3,7,8-TCDD TUMOR PROMOTION ACTIVITY ...

    Science.gov (United States)

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has a high estimated cancer potency in animals which has been reasoned to imply that TCDD might be carcinogenic to man. The animal cancer data show that TCDD can act in a solitary manner causing tumors without the participation of other known factors. owever, there exist animal cancer data indicating that TCDD can act as a tumor-promoting compound. This analysis examines which type of carcinogen and which mechanism best characterize TCDD cancer activity. It is suggested that TCDD acts by a hormonal mechanism to cause cancer in solitary manner, at low doses, in two species, and in a number of different organs, including rare sites. These observations in toto characterize TCDD as a complete carcinogen, which by definition encompasses both initiation and promotion carcinogenic activities. This analysis examines which type of carcinogen and which mechanism best characterize TCDD cancer activity. It is suggested that TCDD acts by a hormonal mechanism to cause cancer in solitary manner, at low doses, in two species, and in a number of different organs, including rare sites

  19. Aryl hydrocarbon receptor-dependent upregulation of Cyp1b1 by TCDD and diesel exhaust particles in rat brain microvessels

    Directory of Open Access Journals (Sweden)

    Jacob Aude

    2011-08-01

    Full Text Available Abstract Background AhR activates the transcription of several target genes including CYP1B1. Recently, we showed CYP1B1 as the major cytochrome P450 (CYP enzyme expressed in human brain microvessels. Here, we studied the effect of AhR activation by environmental pollutants on the expression of Cyp1b1 in rat brain microvessels. Methods Expression of AhR and Cyp1b1 was detected in isolated rat brain microvessels. AhR was immunovisualised in brain microvessel endothelial cells. The effect of AhR ligands on Cyp1b1 expression was studied using isolated brain microvessels after ex vivo and/or in vivo exposure to TCDD, heavy hydrocarbons containing diesel exhaust particles (DEP or Δ9-tetrahydrocannabinol (Δ9-THC. Results After ex vivo exposure to TCDD (a highly potent AhR ligand for 3 h, Cyp1b1 expression was significantly increased by 2.3-fold in brain microvessels. A single i.p. dose of TCDD also increased Cyp1b1 transcripts (22-fold and Cyp1b1 protein (2-fold in rat brain microvessels at 72 h after TCDD. Likewise, DEP treatment (in vivo and ex vivo strongly induced Cyp1b1 protein in brain microvessels. DEP-mediated Cyp1b1 induction was inhibited by actinomycin D, cycloheximide, or by an AhR antagonist. In contrast, a sub-chronic in vivo treatment with Δ9-THC once daily for 7 seven days had no effect on Cyp1b1 expression Conclusions Our results show that TCDD and DEP strongly induced Cyp1b1 in rat brain microvessels, likely through AhR activation.

  20. Fractional Excretion of Survivin, Extracellular Matrix Metalloproteinase Inducer, and Matrix Metalloproteinase 7 in Children with Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Agnieszka Bargenda

    2016-07-01

    Full Text Available Background: Epithelial–mesenchymal transition (EMT is defined as a transformation of tubular epithelial cells into mesenchymal ones. These cells migrate through the extracellular matrix and change into active myofibroblasts, which are responsible for excessive matrix deposition. Such changes may lead to tubular dysfunction and fibrosis of the renal parenchyma, characteristic of chronic kidney disease (CKD. However, there are no data on potential EMT markers in children with CKD. The aim of our study was to assess the usefulness of fractional excretion (FE of survivin, E-cadherin, extracellular matrix metalloproteinase inducer (EMMPRIN, matrix metalloproteinase (MMP7, and transforming growth factor beta 1 (TGF-β1 as potential markers of CKD-related complications such as tubular damage and fibrosis. Methods: Forty-one pre-dialysis children with CKD Stages 3–5 and 23 age-matched controls were enrolled in the study. The serum and urine concentrations of analysed parameters were assessed by an enzyme-linked immunosorbent assay test. Results: Tubular reabsorption of all analysed parameters was >99% in the control group. All FE values rose significantly in children with CKD, yet they remained 1%. Conclusions: FE of the examined markers may become a useful tool in the assessment of tubular dysfunction during the course of CKD. The FE of survivin, EMMPRIN, and MMP7 warrant further research as potential independent markers of kidney-specific EMT.

  1. Integrin-linked kinase is involved in matrix-induced hepatocyte differentiation

    International Nuclear Information System (INIS)

    Gkretsi, Vasiliki; Bowen, William C.; Yang, Yu; Wu, Chuanyue; Michalopoulos, George K.

    2007-01-01

    Hepatocytes have restricted proliferative capacity in culture and when cultured without matrix, lose the hepatocyte-specific gene expression and characteristic cellular micro-architecture. Overlay of matrix-preparations on de-differentiated hepatocytes restores differentiation. Integrin-linked kinase (ILK) is a cell-matrix-adhesion protein crucial in fundamental processes such as differentiation and survival. In this study, we investigated the role of ILK, and its binding partners PINCH, α-parvin, and Mig-2 in matrix-induced hepatocyte differentiation. We report here that ILK is present in the liver and localizes at cell-matrix adhesions of cultured hepatocytes. We also show that ILK, PINCH, α-parvin, and Mig-2 expression level is dramatically reduced in the re-differentiated hepatocytes. Interestingly, hepatocytes lacking ILK undergo matrix-induced differentiation but their differentiation is incomplete, as judged by monitoring cell morphology and production of albumin. Our results show that ILK and cell-matrix adhesion proteins play an important role in the process of matrix-induced hepatocyte differentiation

  2. TCDD causes suppression of growth and differentiation of MCF10A, human mammary epithelial cells by interfering with their insulin receptor signaling through c-Src kinase and ERK activation.

    Science.gov (United States)

    Park, Sujin; Mazina, Olga; Kitagawa, Akira; Wong, Patrick; Matsumura, Fumio

    2004-01-01

    One of the proposed mechanisms of carcinogenic action of TCDD (=dioxin) on breast cells is that it causes significant inhibition of proper differentiation of mammary duct epithelial cells and thereby increases the number of terminal end buds, which are susceptible to other carcinogens (Fenton et al., Toxicol Sci 2002;67:63-74; Brown et al., Carcinogenesis 1998; 19:1623-1629; Lamartiniere, J Mammary Gland Biol Neoplasia 2002;7:67-76). To address this topic, we selected MCF10A, a line of immortalized normal human breast epithelial cells as an in vitro model. An initial effort was made to optimize the cultural condition of MCF10A cells to promote the cell differentiation effect of insulin. Under this condition, TCDD clearly antagonized the action of insulin only in the presence of cholera toxin that is known to promote the differentiation of normal human breast epithelial cells. To test the hypothesis that TCDD-induced c-Src kinase activation is casually related to this compound's antagonistic action against insulin, we treated MCF10A cells with two c-Src blocking agents, an anti-Src antisense oligonucleotides blocker and a known specific inhibitor of c-Src kinase, PP-2 and studied the effect of insulin and TCDD on cell proliferation. The results showed that, in cells treated with either of these two c-Src blocking agents, the antagonistic effect of TCDD disappeared. It was also found that agents which specifically block the activation of ERK could also abrogate the action of TCDD to suppress insulin signaling. Together, these results indicate that the mechanism of the antagonistic action of TCDD on insulin signaling is mainly mediated through c-Src signaling through activation of ERK.

  3. Cell contraction induces long-ranged stress stiffening in the extracellular matrix.

    Science.gov (United States)

    Han, Yu Long; Ronceray, Pierre; Xu, Guoqiang; Malandrino, Andrea; Kamm, Roger D; Lenz, Martin; Broedersz, Chase P; Guo, Ming

    2018-04-04

    Animal cells in tissues are supported by biopolymer matrices, which typically exhibit highly nonlinear mechanical properties. While the linear elasticity of the matrix can significantly impact cell mechanics and functionality, it remains largely unknown how cells, in turn, affect the nonlinear mechanics of their surrounding matrix. Here, we show that living contractile cells are able to generate a massive stiffness gradient in three distinct 3D extracellular matrix model systems: collagen, fibrin, and Matrigel. We decipher this remarkable behavior by introducing nonlinear stress inference microscopy (NSIM), a technique to infer stress fields in a 3D matrix from nonlinear microrheology measurements with optical tweezers. Using NSIM and simulations, we reveal large long-ranged cell-generated stresses capable of buckling filaments in the matrix. These stresses give rise to the large spatial extent of the observed cell-induced matrix stiffness gradient, which can provide a mechanism for mechanical communication between cells.

  4. EVIDENCE FOR EGFR PATHWAY MEDIATION OF CLEFT PALATE INDUCTION BY TCDD

    Science.gov (United States)

    EVIDENCE FOR EGFR PATHWAY MEDIATION OF CLEFT PALATE INDUCTION BY TCDD. B D Abbott, A R Buckalew, and K E Leffler. RTD, NHEERL, ORD,US EPA, RTP, NC, USA.2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is teratogenic in C57BL/6J mice, producing cleft palate (CP) after exposure...

  5. The effect of perinatal TCDD exposure on caries susceptibility in rats.

    Science.gov (United States)

    Miettinen, Hanna M; Sorvari, Rita; Alaluusua, Satu; Murtomaa, Mari; Tuukkanen, Juha; Viluksela, Matti

    2006-06-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), the model compound of polychlorinated dibenzo-p-dioxins and furans, is a potent toxicant with the ability to hamper development. Accidental exposure to TCDD has been linked with various developmental dental aberrations in humans, and experimentally it has been shown that TCDD causes, among other defects, hypomineralization of dental hard tissues in rodents. Here, we studied the effect of very low perinatal TCDD exposure on dental caries susceptibility and mineral composition of tooth enamel in rats. Pregnant line C rats (rat line developed in our laboratory) were dosed 0.03-1.0 microg/kg TCDD on gestation day 15 and allowed to give birth and nurse until weaning on postnatal day 21. The offspring were challenged with cariogenic treatment including sugar-rich diet and three inoculations with Streptococcus mutans. Control groups involved animals with or without cariogenic challenge or TCDD treatment. The number of caries lesions in left lower molars was determined by Schiff's staining after 8 weeks of weaning. TCDD treatment increased cariogenic lesions in the enamel at the lowest maternal dose used, 0.03 microg/kg, and at the highest maternal dose, 1 microg/kg, the lesions extended through the enamel to dentin more frequently. Changes in mineral composition measured by electron probe microanalyzer, scanning electron microscopy, and energy-dispersive spectrometry could not explain the increased caries susceptibility. In conclusion, perinatal TCDD exposure can render rat molars more susceptible to caries.

  6. IgE-mediated basophil tumour necrosis factor alpha induces matrix metalloproteinase-9 from monocytes

    DEFF Research Database (Denmark)

    Falkencrone, Sidsel; Poulsen, Lars K.; Bindslev-Jensen, Carsten

    2013-01-01

    IgE-mediated activation of mast cells has been reported to induce the release of tumour necrosis alpha (TNF-α), which may display autocrine effects on these cells by inducing the generation of the tissue remodelling protease matrix metalloproteinase-9 (MMP-9). While mast cells and basophils have...

  7. Matrix metalloproteinases with gelatinolytic activity induced by Paracoccidioides brasiliensis infection

    Science.gov (United States)

    Nishikaku, Angela Satie; Ribeiro, Luciana Cristina; Molina, Raphael Fagnani Sanchez; Albe, Bernardo Paulo; Cunha, Cláudia da Silva; Burger, Eva

    2009-01-01

    Matrix metalloproteinases (MMPs) modulate extracellular matrix turnover, inflammation and immunity. We studied MMP-9 and MMP-2 in experimental paracoccidioidomycosis. At 15 and 120 days after infection (DAI) with virulent Paracoccidioides brasiliensis, MMP-9 was positive by immunohistochemistry in multinucleated giant cells, in mononuclear cells with macrophage and lymphocyte morphologies and also in fungal cells in the lesions of susceptible and resistant mice. Using gelatin zymography, pro- and active MMP-9 and active MMP-2 were detected in all infected mice, but not in controls. Gelatinolytic activity was not observed in P. brasiliensis extracts. Semiquantitative analysis of gelatinolytic activities revealed weak or absent MMP-2 and strong MMP-9 activity in both mouse strains at 15 DAI, declining at 120 DAI. Avirulent P. brasiliensis-infected mice had residual lesions with MMP-9-positive pseudoxantomatous macrophages, but no gelatinase activity at 120 DAI. Our findings demonstrate the induction of MMPs, particularly MMP-9, in experimental paracoccidioidomycosis, suggesting a possible influence in the pattern of granulomas and in fungal dissemination. PMID:19765107

  8. Rhubarb Antagonizes Matrix Metalloproteinase-9-induced Vascular Endothelial Permeability

    Directory of Open Access Journals (Sweden)

    Yun-Liang Cui

    2016-01-01

    Conclusions: The rhubarb mixture of emodin, 3,8-dihydroxy-1-methyl-anthraquinone-2-carboxylic acid, 1-O-caffeoyl-2-(4-hydroxyl-O-cinnamoyl-β-D-glucose, daucosterol linoleate, and rhein, at a low concentration, antagonized the MMP9-induced HUVEC monolayer permeability by promoting HUVEC proliferation and reducing extracellular VE-cadherin concentrations.

  9. Extracellular Matrix Induced Integrin Signal Transduction and Breast Cancer Invasion.

    Science.gov (United States)

    1995-10-01

    were shown to express matrilysin; a MMP that is primarily expressed in normal and neoplastic cells of epithelial origin . Stromelysin-1 was induced in...phenotypes. This area of research was not proposed in the original fellowship but it complements the information obtained from the in vitro tissue culture...metalloproteinase with potentially novel functions. International Journal of Biochemistry and Cell Biology In Press: Wolf C, Rouyer N, Lutz Y, Adida C, Loriot M

  10. Characterization of anti-apoptotic action of TCDD as a defensive cellular stress response reaction against the cell damaging action of ultra-violet irradiation in an immortalized normal human mammary epithelial cell line, MCF10A.

    Science.gov (United States)

    Park, Sujin; Matsumura, Fumio

    2006-01-16

    It was originally shown by Woerner and Schrenk [Woerner, W., Schrenk, D., 1998. 2,3,7,8-Tetrachlorodibenzo-p-dioxin suppresses apoptosis and leads to hyperphosphorylation of p53 in rat hepatocytes. Environ. Toxicol. Pharmacol. 6, 239-247] that TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) acts as an antagonist against the action of UV-irradiation to induce apoptosis in rat primary hepatocytes. Since prevention of apoptosis has been shown to promote carcinogenesis, we have decided to investigate this phenomenon in a human mammary gland epithelial cell line, MCF10A. We found that, in this cell line, TCDD can antagonize apoptosis that was induced by a variety of treatments, such as UV- and gamma-irradiation, growth factor starvation and trypsinization, or by the addition of H(2)O(2), TGFbeta, and staurosporine. Furthermore, other agents that are known to elicit defensive cellular responses, such as LPS, Fe(3+), nitric oxide and hypoxia could also antagonize UV induced apoptosis just as in the case of TCDD. In addition, we found that, in this cell line, such anti-apoptotic action of TCDD resembles that of exogenously added EGF or TGF alpha. To study the basic mechanism of such an action of TCDD, we tested a variety of diagnostic agents to reverse the effect of TCDD. Antagonists of TCDD which were found to be effective in this way were (a) inhibitors of c-Src kinase, such as PP-2 and CGP77675, (b) those known to block the action of TGF alpha, such as anti-TGF alpha antibody, and alpha(1)-antitrypsin, (c) PD98059, a specific inhibitor of ERK activation, but not SB202190 (an inhibitor of p38 MAPK activation) or SP600125 (a JNK inhibitor) and (d) Ah receptor antagonists, alpha-naphthoflavone and 1, 10-phenanthroline. These results support the notion that TCDD acts as an anti-apoptotic agent by mimicking the action of EGF through activation of the c-Src/ERK signaling pathway.

  11. Extracellular matrix induces doxorubicin-resistance in human osteosarcoma cells by suppression of p53 function.

    Science.gov (United States)

    Harisi, Revekka; Dudas, Jozsef; Nagy-Olah, Julia; Timar, Ferenc; Szendroi, Miklos; Jeney, Andras

    2007-08-01

    Osteosarcoma is the most common primary malignant bone tumor in childhood and adolescence. The several chemotherapy-resistant cases of osteosarcoma are at a higher risk of relapse and adverse outcome. The aim of the current study was to determine the role of extracellular matrix in the resistance developed against chemotherapeutic treatments of human osteosarcoma cells. A cell line, named OSCORT was established from the biopsy of a 17-year-old male patient with primary osteosarcoma. Cell proliferation, apoptosis and quantification of DNA damage after treatments with doxorubicin were investigated in classical and three-dimensional cell culture systems using an extracellular matrix gel. The experimental results were related to the clinical observations of the case. The cells cultured in extracellular matrix gel have shown resistance to doxorubicin similar to that seen in the clinical case, as demonstrated by their proliferation, apoptosis and doxorubicin-induced DNA damage characteristics. Among the extracellular matrix components, the heparan sulfate proteoglycan and-to a lesser extent-fibronectin were involved in the doxorubicin resistance. Laminin and nidogen did not decrease the cytoreductive effect of doxorubicin, while collagen IV even increased it. The extracellular matrix gel decreased the protein levels of p53 and abrogated its cell nuclear translocalization. The most frequent known mutations in the p53 gene were not found in OSCORT cells. The current study provides experimental evidence for an epigenetical, extracellular matrix-induced loss of p53 function, which lead to a potent chemotherapy resistance showing accordance with the clinical experience.

  12. Studies of matrix vesicle-induced mineralization in a gelatin gel

    Science.gov (United States)

    Boskey, A. L.; Boyan, B. D.; Doty, S. B.; Feliciano, A.; Greer, K.; Weiland, D.; Swain, L. D.; Schwartz, Z.

    1992-01-01

    Matrix vesicles isolated from fourth-passage cultures of chondrocytes were tested for their ability to induce hydroxyapatite formation in a gelatin gel in order to gain insight into the function of matrix vesicles in in situ mineralization. These matrix vesicles did not appear to be hydroxyapatite nucleators per se since the extent of mineral accumulation in the gel diffusion system was not altered by the presence of matrix vesicles alone, and in the vesicle containing gels, mineral crystals were formed whether associated with vesicles or not. In gels with these matrix vesicles and beta-glycerophosphate, despite the presence of alkaline phosphatase activity, there was no increase in mineral deposition. This suggested that in the gel system these culture-derived vesicles did not increase local phosphate concentrations. However, when known inhibitors of mineral crystal formation and growth (proteoglycan aggregates [4 mg/ml], or ATP [1 mM], or both proteoglycan and ATP) were included in the gel, more mineral was deposited in gels with the vesicles than in comparable gels without vesicles, indicating that enzymes within these vesicles were functioning to remove the inhibition. These data support the suggestion that one function of the extracellular matrix vesicles is to transport enzymes for matrix modification.

  13. Significance of Shrinkage Induced Clamping Pressure in Fiber-Matrix Bonding in Cementitious Composite Materials

    DEFF Research Database (Denmark)

    Stang, Henrik

    1996-01-01

    used in high performance cementitious composite materials.Assuming a Coulomb type of friction on the fiber/matrix interface andusing typical values for the frictional coefficient it is shownthat the shrinkage induced clamping pressure could be one of the mostimportant factors determining the frictional...

  14. TCDD dysregulation of 13 AHR-target genes in rat liver

    International Nuclear Information System (INIS)

    Watson, John D.; Prokopec, Stephenie D.; Smith, Ashley B.; Okey, Allan B.; Pohjanvirta, Raimo; Boutros, Paul C.

    2014-01-01

    Despite several decades of research, the complete mechanism by which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other xenobiotic agonists of the aryl hydrocarbon receptor (AHR) cause toxicity remains unclear. While it has been shown that the AHR is required for all major manifestations of toxicity, the specific downstream changes involved in the development of toxic phenotypes remain unknown. Here we examine a panel of 13 genes that are AHR-regulated in many species and tissues. We profiled their hepatic mRNA abundances in two rat strains with very different sensitivities to TCDD: the TCDD-sensitive Long–Evans (Turku/AB; L–E) and the TCDD-resistant Han/Wistar (Kuopio; H/W). We evaluated doses ranging from 0 to 3000 μg/kg at 19 h after TCDD exposure and time points ranging from 1.5 to 384 h after exposure to 100 μg/kg TCDD. Twelve of 13 genes responded to TCDD in at least one strain, and seven of these showed statistically significant inter-strain differences in the time course analysis (Aldh3a1, Cyp1a2, Cyp1b1, Cyp2a1, Fmo1, Nfe2l2 and Nqo1). Cyp2s1 did not respond to TCDD in either rat strain. Five genes exhibited biphasic responses to TCDD insult (Ahrr, Aldh3a1, Cyp1b1, Nfe2l2 and Nqo1), suggesting a secondary event, such as association with additional transcriptional modulators. Of the 12 genes that responded to TCDD during the dose–response analysis, none had an ED 50 equivalent to that of Cyp1a1, the most sensitive gene in this study, while nine genes responded to doses at least 10–100 fold higher, in at least one strain (Ahrr (L–E), Aldh3a1 (both), Cyp1a2 (both), Cyp1b1 (both), Cyp2a1 (L–E), Inmt (both), Nfe2l2 (L–E), Nqo1 (L–E) and Tiparp (both)). These data shed new light on the association of the AHR target genes with TCDD toxicity, and in particular the seven genes exhibiting strain-specific differences represent strong candidate mediators of Type-II toxicities. - Highlights: • NanoString measured hepatic mRNA molecules following

  15. Mechanism of radiation-induced degradation in mechanical properties of polymer matrix composites

    International Nuclear Information System (INIS)

    Egusa, Shigenori

    1988-01-01

    Four kinds of polymer matrix composites (filler, E-glass or carbon fibre cloth; matrix, epoxy or polyimide resin) and pure epoxy and polyimide resins were irradiated with 60 Co γ-rays or 2 MeV electrons at room temperature. Mechanical tests were then carried out at 77K and at room temperature. Following irradiation, the Young's (tensile) modulus of these composites and pure resins remains practically unchanged even at 170 MGy for both test temperatures. The ultimate strength, however, decreases appreciably with increasing dose. The dose dependence of the composite strength depends not only on the combination of fibre and matrix in the composite but also on the test temperature. A relationship is found between the composite ultimate strain and the matrix ultimate strain, thus indicating that the dose dependence of the composite strength is virtually determined by a change in the matrix ultimate strain due to irradiation. Based on this finding, we propose a mechanism of radiation-induced degradation of a polymer matrix composite in order to explain the dose dependence of the composite strength measured at 77 K and at room temperature. (author)

  16. [Expression of various matrix metalloproteinases in mice with hyperoxia-induced acute lung injury].

    Science.gov (United States)

    Zhang, Xiang-feng; Ding, Shao-fang; Gao, Yuan-ming; Liang, Ying; Foda, Hussein D

    2006-08-01

    To investigate the role of matrix metalloproteinases (MMPs) and extracellular matrix metalloproteinase inducer (EMMPRIN) in the pathogenesis of acute lung injury induced by hyperoxia. Fifty four mice were exposed in sealed cages to >98% oxygen (for 24-72 hours), and another 18 mice to room air. The severity of lung injury was assessed, and the expression of mRNA and protein of MMP-2, MMP-9 and EMMPRIN in lung tissue, after exposure for 24, 48 and 72 hours of hyperoxia were studied by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. Hyperoxia caused acute lung injury; this was accompanied by increased expression of an upregulation of MMP-2, MMP-9 and EMMPRIN mRNA and protein in lung tissues. Hyperoxia causes acute lung injury in mice; increases in MMP-2, MMP-9 and EMMPRIN may play an important role in the development of hyperoxia induced lung injury in mice.

  17. Immunological characterization of the aryl hydrocarbon receptor (AHR) knockout rat in the presence and absence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

    International Nuclear Information System (INIS)

    Phadnis-Moghe, Ashwini S.; Chen, Weimin; Li, Jinpeng; Crawford, Robert B.; Bach, Anthony; D’Ingillo, Shawna; Kovalova, Natalia; Suarez-Martinez, Jose E.; Kaplan, Barbara L.F.; Harrill, Joshua A.; Budinsky, Robert; Rowlands, J. Craig; Thomas, Russell S.

    2016-01-01

    The aryl hydrocarbon receptor (AHR) has been extensively characterized for the essential role it plays in mediating the toxic responses elicited by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Despite similarities across animal species, species-specific differences exist in the profile of toxicity and sensitivity to TCDD owing, in part, to differences in the AHR. Newer reports have implicated the importance of AHR in the development and regulation of the immune system. Our present studies seek to further explore the essential role of AHR in lymphoid tissue composition, B cell function and the immunological responses after TCDD administration using the recently established AHR KO rats. Comprehensive immune cell phenotyping showed a decrease in the CD8 + T cell, CD11c + populations and an increase in NKT cells in 3-week-old AHR KO rats compared to the WT controls. The lipopolysaccharide-induced IgM response and proliferation was markedly suppressed in the WT but not in the AHR KO B cells in the presence of TCDD. However, the percentage of LPS-activated IgM + B cells was significantly higher in the AHR KO B cells as compared to that of WT suggesting the role of AHR in regulating the IgM response. The use of an AHR antagonist further alluded to the endogenous role of AHR in regulating B cell responses in the rat. Overall, the studies report for the first time, comprehensive immune cell phenotyping of the AHR KO rat and the endogenous role of AHR in the regulation of B cell function in the rat.

  18. Expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and its related extracellular matrix degrading enzymes in the endometrium during estrous cycle and early gestation in cattle

    OpenAIRE

    Hosoe Misa; Takahashi Toru; Ushizawa Koichi; Koshi Katsuo; Kizaki Keiichiro; Mishra Birendra; Sato Takashi; Ito Akira; Hashizume Kazuyoshi

    2010-01-01

    Abstract Background Extracellular matrix metalloproteinase inducer (EMMPRIN) regulates several biological functions involving the modulation of cell behaviors via cell-cell and cell-matrix interactions. According to its diverse functions, we hypothesized that EMMPRIN may play an important role in endometrial remodeling and establishment of pregnancy in cow. Methods In this study, endometrial tissues from the cyclic cows during before ovulation, after ovulation and middle of estrous cycle; and...

  19. Significance of Shrinkage Induced Clamping Pressure in Fiber-Matrix Bonding in Cementitious Composite Materials

    DEFF Research Database (Denmark)

    Stang, Henrik

    1996-01-01

    used in high performance cementitious composite materials.Assuming a Coulomb type of friction on the fiber/matrix interface andusing typical values for the frictional coefficient it is shownthat the shrinkage induced clamping pressure could be one of the mostimportant factors determining the frictional......The present paper accesses the significance of shrinkage inducedclamping pressure in fiber/matrix bonding mechanisms incementitious composite materials. The paper contains a description of an experimental setup whichallows mbox{measurement} of the clamping pressure which develops on anelastic...... inhomogeneity embedded in a matrix consisting of acementitious material undergoing shrinkage during hydration(autogenous shrinkage). Furthermore, the paperpresents the analysis necessary to perform an interpretation of the experimental results and which allows for thedetermination of the clamping pressure...

  20. Use of shell model calculations in R-matrix studies of neutron-induced reactions

    International Nuclear Information System (INIS)

    Knox, H.D.

    1986-01-01

    R-matrix analyses of neutron-induced reactions for many of the lightest p-shell nuclei are difficult due to a lack of distinct resonance structure in the reaction cross sections. Initial values for the required R-matrix parameters, E,sub(lambda) and γsub(lambdac) for states in the compound system, can be obtained from shell model calculations. In the present work, the results of recent shell model calculations for the lithium isotopes have been used in R-matrix analyses of 6 Li+n and 7 Li+n reactions for E sub(n) 7 Li and 8 Li on the 6 Li+n and 7 Li+n reaction mechanisms and cross sections are discussed. (author)

  1. Effect of thyroidectomy and thyroxine on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced immunotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Pazdernik, T.L.; Rozman, K.K.

    1985-02-18

    Radiothyroidectomy protected against 2,3,7,8-tetrachloro dibenzo-p-dioxin (TCDD)-induced immunotoxicity in rats as assessed by the spleen anti-SRBC plaque-forming cell assay. Thyroxin (T/sub 4/) replacement therapy partially reversed the effects of thyroidectomy on T/sub 4/ and triiodothyronine (T/sub 3/) serum levels, body weight and immune function as well as restored TCDD-induced immunotoxicity. Thus, hypothyroidism induced by TCDD exposure can be viewed as a protective response of the organism to reduce the insult caused by TCDD.

  2. Effect of thyroidectomy and thyroxine on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced immunotoxicity

    International Nuclear Information System (INIS)

    Pazdernik, T.L.; Rozman, K.K.

    1985-01-01

    Radiothyroidectomy protected against 2,3,7,8-tetrachloro dibenzo-p-dioxin (TCDD)-induced immunotoxicity in rats as assessed by the spleen anti-SRBC plaque-forming cell assay. Thyroxin (T 4 ) replacement therapy partially reversed the effects of thyroidectomy on T 4 and triiodothyronine (T 3 ) serum levels, body weight and immune function as well as restored TCDD-induced immunotoxicity. Thus, hypothyroidism induced by TCDD exposure can be viewed as a protective response of the organism to reduce the insult caused by TCDD

  3. Ramipril inhibits AGE-RAGE-induced matrix metalloproteinase-2 activation in experimental diabetic nephropathy

    OpenAIRE

    Fukami, Kei; Yamagishi, Sho-ichi; Coughlan, Melinda T; Harcourt, Brooke E; Kantharidis, Phillip; Thallas-Bonke, Vicki; Okuda, Seiya; Cooper, Mark E; Forbes, Josephine M

    2014-01-01

    Background Advanced glycation end products (AGE)-receptor for AGE (RAGE) axis and renin-angiotensin system (RAS) play a role in diabetic nephropathy (DN). Matrix metalloproteinase-2 (MMP-2) activation also contributes to DN. However, the pathological interaction among AGE-RAGE, RAS and MMP-2 in DN remains unknown. We examined here the involvement of AGE and RAS in MMP-2 activation in streptozotocin (STZ)-induced diabetic rats and in AGE-exposed rat renal proximal tubular cells (RPTCs). Method...

  4. α2 Integrin, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-3 act sequentially to induce differentiation of mouse embryonic stem cells into odontoblast-like cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Kawai, Rie; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan)

    2015-02-01

    We previously reported that interleukin 1β acts via matrix metalloproteinase (MMP)-3 to regulate cell proliferation and suppress apoptosis in α2 integrin-positive odontoblast-like cells differentiated from mouse embryonic stem (ES) cells. Here we characterize the signal cascade underpinning odontoblastic differentiation in mouse ES cells. The expression of α2 integrin, extracellular matrix metalloproteinase inducer (Emmprin), and MMP-3 mRNA and protein were all potently increased during odontoblastic differentiation. Small interfering RNA (siRNA) disruption of the expression of these effectors potently suppressed the expression of the odontoblastic biomarkers dentin sialophosphoprotein, dentin matrix protein-1 and alkaline phosphatase, and blocked odontoblast calcification. Our siRNA, western blot and blocking antibody analyses revealed a unique sequential cascade involving α2 integrin, Emmprin and MMP-3 that drives ES cell differentiation into odontoblasts. This cascade requires the interaction between α2 integrin and Emmprin and is potentiated by exogenous MMP-3. Finally, although odontoblast-like cells potently express α2, α6, αV, β1, and β3, integrins, we confirmed that β1 integrin acts as the trigger for ES cell differentiation, apparently in complex with α2 integrin. These results demonstrate a unique and unanticipated role for an α2 integrin-, Emmprin-, and MMP-3-mediated signaling cascade in driving mouse ES cell differentiation into odontoblast-like cells. - Highlights: • Odontoblast differentiation requires activation of α2 integrin, Emmprin and MMP-3. • α2 integrin, Emmprin and MMP-3 form a sequential signaling cascade. • β1 integrin acts a specific trigger for odontoblast differentiation. • The role of these effectors is highly novel and unanticipated.

  5. Polyphosphate induces matrix metalloproteinase-3-mediated proliferation of odontoblast-like cells derived from induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Hase, Naoko; Yamaguchi, Hideyuki; Hiyama, Taiki; Kawai, Rie [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan)

    2015-05-01

    Inorganic polyphosphate [Poly(P)] may represent a physiological source of phosphate and has the ability to induce bone differentiation in osteoblasts. We previously reported that cytokine-induced matrix metalloproteinase (MMP)-3 accelerates the proliferation of purified odontoblast-like cells. In this study, MMP-3 small interfering RNA (siRNA) was transfected into odontoblast-like cells derived from induced pluripotent stem cells to investigate whether MMP-3 activity is induced by Poly(P) and/or is associated with cell proliferation and differentiation into odontoblast-like cells. Treatment with Poly(P) led to an increase in both cell proliferation and additional odontoblastic differentiation. Poly(P)-treated cells showed a small but significant increase in dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1) mRNA expression, which are markers of mature odontoblasts. The cells also acquired additional odontoblast-specific properties including adoption of an odontoblastic phenotype typified by high alkaline phosphatase (ALP) activity and a calcification capacity. In addition, Poly(P) induced expression of MMP-3 mRNA and protein, and increased MMP-3 activity. MMP-3 siRNA-mediated disruption of the expression of these effectors potently suppressed the expression of odontoblastic biomarkers ALP, DSPP, and DMP-1, and blocked calcification. Interestingly, upon siRNA-mediated silencing of MMP-3, we noted a potent and significant decrease in cell proliferation. Using specific siRNAs, we revealed that a unique signaling cascade, Poly(P)→MMP-3→DSPP and/or DMP-1, was intimately involved in the proliferation of odontoblast-like cells. - Highlights: • Polyphosphate increases proliferation of iPS cell-derived odontoblast-like cells. • Polyphosphate-induced MMP-3 results in an increase of cell proliferation. • Induced cell proliferation involves MMP-3, DSPP, and/or DMP-1 sequentially. • Induced MMP-3 also results in an increase of odontoblastic

  6. Repair Potential of Matrix-Induced Bone Marrow Aspirate Concentrate and Matrix-Induced Autologous Chondrocyte Implantation for Talar Osteochondral Repair

    Science.gov (United States)

    Desando, Giovanna; Bartolotti, Isabella; Vannini, Francesca; Cavallo, Carola; Castagnini, Francesco; Buda, Roberto; Giannini, Sandro; Mosca, Massimiliano; Mariani, Erminia; Grigolo, Brunella

    2016-01-01

    Objective The low regenerative potential of cartilage contributed to the development of different cell therapies aimed to improve the clinical outcome in young patients with Osteochondral Lesions of the Talus (OLT). This study is designed to assess the regenerative potential of autologous matrix-induced Bone Marrow Aspirate Concentrate (mBMAC) and matrix-induced Autologous Chondrocyte Implantation (mACI) evaluating, on a small number of osteochondral biopsies, the expression of some catabolic, inflammatory, and pain mediators. Design Twenty-two patients with OLT were analyzed in this study; 7 were treated with mACI and 15 with mBMAC. Informed consent was obtained from all the patients. Clinical assessments were performed pre-operatively and at 12, 24, and 36 months after surgery using the American Orthopedic Foot and Ankle Society (AOFAS). Histology and immunohistochemistry were used to assess cartilage repair at 24 months. Data were analyzed using non-parametric Wilcoxon-Mann-Whitney and Spearman tests. Results A remarkable improvement in AOFAS score was noticed for both treatments up to 36 months; however, patients treated with mACI reported the best AOFAS score. Various degrees of tissue remodeling were observed by histological analysis for both cell strategies. However, mBMAC treatment showed a higher expression of some fibrous and hypertrophic markers compared to mACI group. A mild positivity for nerve growth factor, as pain mediator, was noticed for both treatments.M Conclusions Our findings demonstrated the best histological and clinical results following mACI treatment since different fibrotic and hypertrophic features were evident in the mBMAC group at 24-month follow-up. PMID:27994720

  7. Faslodex inhibits estradiol-induced extracellular matrix dynamics and lung metastasis in a model of lymphangioleiomyomatosis.

    Science.gov (United States)

    Li, Chenggang; Zhou, Xiaobo; Sun, Yang; Zhang, Erik; Mancini, John D; Parkhitko, Andrey; Morrison, Tasha A; Silverman, Edwin K; Henske, Elizabeth P; Yu, Jane J

    2013-07-01

    Lymphangioleiomyomatosis (LAM) is a destructive lung disease primarily affecting women. Genetic studies indicate that LAM cells carry inactivating tuberous sclerosis complex (TSC)-2 mutations, and metastasize to the lung. We previously discovered that estradiol increases the metastasis of TSC2-deficient cells in mice carrying xenograft tumors. Here, we investigate the molecular basis underlying the estradiol-induced lung metastasis of TSC2-deficient cells, and test the efficacy of Faslodex (an estrogen receptor antagonist) in a preclinical model of LAM. We used a xenograft tumor model in which estradiol induces the lung metastasis of TSC2-deficient cells. We analyzed the impact of Faslodex on tumor size, the extracellular matrix organization, the expression of matrix metalloproteinase (MMP)-2, and lung metastasis. We also examined the effects of estradiol and Faslodex on MMP2 expression and activity in tuberin-deficient cells in vitro. Estradiol resulted in a marked reduction of Type IV collagen deposition in xenograft tumors, associated with 2-fold greater MMP2 concentrations compared with placebo-treated mice. Faslodex normalized the Type IV collagen changes in xenograft tumors, enhanced the survival of the mice, and completely blocked lung metastases. In vitro, estradiol enhanced MMP2 transcripts, protein accumulation, and activity. These estradiol-induced changes in MMP2 were blocked by Faslodex. In TSC2-deficient cells, estradiol increased MMP2 concentrations in vitro and in vivo, and induced extracellular matrix remodeling. Faslodex inhibits the estradiol-induced lung metastasis of TSC2-deficient cells. Targeting estrogen receptors with Faslodex may be of efficacy in the treatment of LAM.

  8. A regularized matrix factorization approach to induce structured sparse-low-rank solutions in the EEG inverse problem

    DEFF Research Database (Denmark)

    Montoya-Martinez, Jair; Artes-Rodriguez, Antonio; Pontil, Massimiliano

    2014-01-01

    We consider the estimation of the Brain Electrical Sources (BES) matrix from noisy electroencephalographic (EEG) measurements, commonly named as the EEG inverse problem. We propose a new method to induce neurophysiological meaningful solutions, which takes into account the smoothness, structured...... matrix and the squared Frobenius norm of the latent source matrix. We develop an alternating optimization algorithm to solve the resulting nonsmooth-nonconvex minimization problem. We analyze the convergence of the optimization procedure, and we compare, under different synthetic scenarios...

  9. Buddleja officinalis inhibits high glucose-induced matrix metalloproteinase activity in human umbilical vein endothelial cells.

    Science.gov (United States)

    Lee, Yun Jung; Kang, Dae Gill; Kim, Jin Sook; Lee, Ho Sub

    2008-12-01

    The aim of the present investigation was to investigate whether an aqueous extract of Buddleja officinalis (ABO), a traditional Korean herbal medicine, suppresses the endothelial extracellular matrix degradation under high glucose condition. The incubation with high concentration of glucose (25 mM) increased significantly matrix metalloproteinase (MMP)-2/-9 expressions and activities in primary cultured human umbilical vein endothelial cells (HUVEC). Pretreatment with ABO decreased high glucose-induced increase of MMP-2/-9 activities in a dose-dependent manner. Real time qRT-PCR revealed that high glucose-induced MMP-2/-9 mRNA expression levels were attenuated by pretreatment with ABO. High glucose-induced MCP-1 and IL-8 mRNA expression levels also decreased by ABO. ABO decreased high glucose-induced hydrogen peroxide production, oxidative stress marker. These results provide new insights into the pathophysiological mechanisms for anti-inflammatory properties of ABO in vascular diseases associated with diabetes mellitus. (c) 2008 John Wiley & Sons, Ltd.

  10. Procedure for Matrix Effect Reduction in Metal Analysis Using Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Al-Eshaikh, M. A.

    2017-09-01

    A procedure for matrix effect reduction is proposed to enhance the precision of quantitative analysis of metal alloys using laser-induced breakdown spectroscopy (LIBS). This procedure is based on a number of successive steps in order to correct the signal fluctuations caused by plasma interaction and the matrix effect. The first step is the selection of optimum parameter settings of the detection system, such as laser power, delay time, and focal distance. The second step is the estimation of the absolute or relative values of impurities on the basis of the internal standard calibration. The third step is the analysis of the metal basis of the alloy used as an internal standard, which requires spectrum averaging, whole integral spectrum normalization, and self-absorption correction. Three sets of metal-based alloys (aluminum, steel, and copper) are used in this investigation as reference standards for calibration and validation. Successive improvements of the quality of calibration curves are observed during the proposed procedure.

  11. R-Matrix Codes for Charged-particle Induced Reactionsin the Resolved Resonance Region

    Energy Technology Data Exchange (ETDEWEB)

    Leeb, Helmut [Technical Univ. of Wien, Vienna (Austria); Dimitriou, Paraskevi [Intl Atomic Energy Agency (IAEA), Vienna (Austria); Thompson, Ian J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-01-01

    A Consultant’s Meeting was held at the IAEA Headquarters, from 5 to 7 December 2016, to discuss the status of R-matrix codes currently used in calculations of charged-particle induced reaction cross sections at low energies. The meeting was a follow-up to the R-matrix Codes meeting held in December 2015, and served the purpose of monitoring progress in: the development of a translation code to enable exchange of input/output parameters between the various codes in different formats, fitting procedures and treatment of uncertainties, the evaluation methodology, and finally dissemination. The details of the presentations and technical discussions, as well as additional actions that were proposed to achieve all the goals of the meeting are summarized in this report.

  12. Extraskeletal and intraskeletal new bone formation induced by demineralized bone matrix combined with bone marrow cells

    International Nuclear Information System (INIS)

    Lindholm, T.S.; Nilsson, O.S.; Lindholm, T.C.

    1982-01-01

    Dilutions of fresh autogenous bone marrow cells in combination with allogeneic demineralized cortical bone matrix were tested extraskeletally in rats using roentgenographic, histologic, and 45 Ca techniques. Suspensions of bone marrow cells (especially diluted 1:2 with culture media) combined with demineralized cortical bone seemed to induce significantly more new bone than did demineralized bone, bone marrow, or composite grafts with whole bone marrow, respectively. In a short-term spinal fusion experiment, demineralized cortical bone combined with fresh bone marrow produced new bone and bridged the interspace between the spinous processes faster than other transplantation procedures. The induction of undifferentiated host cells by demineralized bone matrix is further complemented by addition of autogenous, especially slightly diluted, bone marrow cells

  13. Preconception Omega-3 Fatty Acid Supplementation of Adult Male Mice with a History of Developmental TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) Exposure Prevents Preterm Birth in Unexposed Female Partners

    Science.gov (United States)

    McConaha, Melinda E.; Ding, Tianbing; Lucas, John A.; Arosh, Joe A.; Osteen, Kevin G.; Bruner-Tran, Kaylon L.

    2013-01-01

    We recently reported that adult male C57BL/6 mice exposed in utero to the environmental toxicant TCDD confer an increased risk of preterm birth (PTB) to unexposed females. Risk of PTB was coincident with decreased placental progesterone receptor (PR) mRNA expression and increased toll-like receptor-4 (TLR-4) mRNA expression, suggesting toxicant exposure induced a heightened inflammatory response at the maternal-fetal interface. Since omega-3 fatty acids exhibit anti-inflammatory activity, herein, we provided TCDD-exposed males a fish oil-enriched diet prior to mating. Although PTB was common in control females mated to TCDD-exposed males on the standard diet, fish oil supplementation of TCDD-exposed males eliminated PTB in unexposed partners. We also determined the influence of preconception, paternal fish oil supplementation on the placental inflammatory response in late pregnancy (E18.5) by examining expression of PR and TLR-4 mRNA as well as expression of 15-hydroxy prostaglandin dehydrogenase (PGDH). PGDH catabolizes the inflammatory PGE2 to an inactive form; thus, reduced expression of this enzyme would promote tissue inflammation. Compared to control pregnancies, examination of E18.5 placentas arising from TCDD-exposed males on the standard diet revealed a significant increase in TLR-4 mRNA expression corresponding to a reduction in PR mRNA and PGDH protein expression. In contrast, fish oil supplementation of toxicant-exposed males led to normalization of placental expression of both PR and TLR-4 mRNA and a marked increase in PGDH expression. These studies suggest that a paternal preconception diet which includes omega-3 fatty acids prevents the toxicant-associated increase in the placental inflammatory response at late gestation, preventing PTB. PMID:21653731

  14. Internal damping due to dislocation movements induced by thermal expansion mismatch between matrix and particles in metal matrix composites. [Al/SiC

    Energy Technology Data Exchange (ETDEWEB)

    Girand, C.; Lormand, G.; Fougeres, R.; Vincent, A. (GEMPPM, Villeurbanne (France))

    1993-05-01

    In metal matrix composites (MMCs), the mechanical 1 of the reinforcement-matrix interface is an important parameter because it governs the load transfer from matrix to particles, from which the mechanical properties of these materials are derived. Therefore, it would be useful to set out an experimental method able to characterize the interface and the adjacent matrix behaviors. Thus, a study has been undertaken by means of internal damping (I.D.) measurements, which are well known to be very sensitive for studying irreversible displacements at the atomic scale. More especially, this investigation is based on the fact that, during cooling of MMC's, stress concentrations originating from differences in coefficients of thermal expansion (C.T.E.) of matrix and particles should induce dislocation movements in the matrix surrounding the reinforcement; that is, local microplastic strains occur. Therefore, during I.D. measurements vs temperature these movements should contribute to MMCs I.D. in a process similar to those involved around first order phase transitions in solids. The aim of this paper is to present, in the case of Al/SiC particulate composites, new developments of this approach that has previously led to promising results in the case of Al-Si alloys.

  15. Loss of Matrix Metalloproteinase-13 Attenuates Murine Radiation-Induced Pulmonary Fibrosis

    International Nuclear Information System (INIS)

    Flechsig, Paul; Hartenstein, Bettina; Teurich, Sybille; Dadrich, Monika; Hauser, Kai; Abdollahi, Amir; Groene, Hermann-Josef; Angel, Peter; Huber, Peter E.

    2010-01-01

    Purpose: Pulmonary fibrosis is a disorder of the lungs with limited treatment options. Matrix metalloproteinases (MMPs) constitute a family of proteases that degrade extracellular matrix with roles in fibrosis. Here we studied the role of MMP13 in a radiation-induced lung fibrosis model using a MMP13 knockout mouse. Methods and Materials: We investigated the role of MMP13 in lung fibrosis by investigating the effects of MMP13 deficiency in C57Bl/6 mice after 20-Gy thoracic irradiation (6-MV Linac). The morphologic results in histology were correlated with qualitative and quantitative results of volume computed tomography (VCT), magnetic resonance imaging (MRI), and clinical outcome. Results: We found that MMP13 deficient mice developed less pulmonary fibrosis than their wildtype counterparts, showed attenuated acute pulmonary inflammation (days after irradiation), and a reduction of inflammation during the later fibrogenic phase (5-6 months after irradiation). The reduced fibrosis in MMP13 deficient mice was evident in histology with reduced thickening of alveolar septi and reduced remodeling of the lung architecture in good correlation with reduced features of lung fibrosis in qualitative and quantitative VCT and MRI studies. The partial resistance of MMP13-deficient mice to fibrosis was associated with a tendency towards a prolonged mouse survival. Conclusions: Our data indicate that MMP13 has a role in the development of radiation-induced pulmonary fibrosis. Further, our findings suggest that MMP13 constitutes a potential drug target to attenuate radiation-induced lung fibrosis.

  16. Osteoblasts extracellular matrix induces vessel like structures through glycosylated collagen I

    Energy Technology Data Exchange (ETDEWEB)

    Palmieri, D. [Genetics, DIBIO, University of Genova, Corso Europa 26, 16132 Genova (Italy); Valli, M.; Viglio, S. [Department of Biochemistry, University of Pavia (Italy); Ferrari, N. [Istituto Nazionale per la ricerca sul Cancro, Genova (Italy); Ledda, B.; Volta, C. [Genetics, DIBIO, University of Genova, Corso Europa 26, 16132 Genova (Italy); Manduca, P., E-mail: man-via@unige.it [Genetics, DIBIO, University of Genova, Corso Europa 26, 16132 Genova (Italy)

    2010-03-10

    Extracellular matrix (ECM) plays a fundamental role in angiogenesis affecting endothelial cells proliferation, migration and differentiation. Vessels-like network formation in vitro is a reliable test to study the inductive effects of ECM on angiogenesis. Here we utilized matrix deposed by osteoblasts as substrate where the molecular and structural complexity of the endogenous ECM is preserved, to test if it induces vessel-like network formation by endothelial cells in vitro. ECM is more similar to the physiological substrate in vivo than other substrates previously utilized for these studies in vitro. Osteogenic ECM, prepared in vitro from mature osteoblasts at the phase of maximal deposition and glycosylation of collagen I, induces EAhy926, HUVEC, and HDMEC endothelial cells to form vessels-like structures and promotes the activation of metalloproteinase-2 (MMP-2); the functionality of the p-38/MAPK signaling pathway is required. Osteogenic ECM also induces a transient increase of CXCL12 and a decrease of the receptor CXCR4. The induction of vessel-like networks is dependent from proper glycosylation of collagens and does not occur on osteogenic ECMs if deglycosylated by -galactosidase or on less glycosylated ECMs derived from preosteoblasts and normal fibroblasts, while is sustained on ECM from osteogenesis imperfecta fibroblasts only when their mutation is associated with over-glycosylation of collagen type I. These data support that post-translational glycosylation has a role in the induction in endothelial cells in vitro of molecules conductive to self-organization in vessels-like structures.

  17. Overexpression of matrix metalloproteinase-12 (MMP-12) correlates with radiation-induced lung fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Myung Gu; Jeong, Ye Ji; Lee, Haejune [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Sujae [Hanyang Univ., Seoul (Korea, Republic of)

    2014-05-15

    MMPs are classified into five subgroups: collagenases (MMP-1, MMP-8, MMP-13), gelatinases (MMP-2, MMP-9), stromelysins (MMP-3, MMP-10, MMP-11), as well as metalloelastase (MMP-12), the membrane-type MMPs (MMP14, MMP15), and other MMPS (e. g., MMP-19, and MMP20). MMP-12 (matrix metalloproteinase12), also known as macrophage metalloelastase, was first identified as an elastolytic metalloproteinase secreted by inflammatory macrophages 30 years ago. MMP-12 degrades extracellular matrix (ECM) components to facilitate tissue remodeling. It can degrade elastin and other substrates, such as type IV collagen, fibronectin, laminin, gelatin, vitronectin, entactin, heparin, and chondroitin sulfates. In the lung, MMP-12 is identified in alveolar macrophages of cigarette smokers as an elastolytic MMP. Inactivation of the MMP-12 gene in knockout mice demonstrates a critical role of MMP-12 in smoking-induced chronic obstructive pulmonary disease (COPD). The aim of the present study was to investigate the effects of MMP-12 by radiation in lung, so we evaluate that MMP-12 expression pattern in normal lung tissue and cancer cell following radiation. Radiation induced lung injury most commonly occurs as a result of radiation therapy administered to treat cancer. The present study demonstrates that MMP-12 was highly increased in the lung damaged by radiation Thus, MMP-12 might be of potential relevance as a clinically diagnostic tool and sensitive biomarker for radiation induced lung injury and fibrosis.

  18. Luteolin inhibits matrix metalloproteinase 9 and 2 in azoxymethane-induced colon carcinogenesis.

    Science.gov (United States)

    Pandurangan, A K; Dharmalingam, P; Sadagopan, S K A; Ganapasam, S

    2014-11-01

    The present investigation deals with the antimetastatic role of luteolin (LUT) by inhibiting matrix metalloproteinase (MMP)-9 and -2 in azoxymethane (AOM)-induced colon carcinogenesis in Balb/C mice. Animals received AOM at a dosage of 15 mg/kg body weight intraperitoneally once a week for 3 weeks. AOM-induced mice was treated with LUT (1.2 mg of LUT/kg body weight/day orally). After the experimental period, the tumor markers such as γ-glutamyl transferase (GGT), 5' nucleotidase (5'ND), cathepsin-D (Cat-D), and carcinoembroyonic antigen (CEA) were elevated upon induction with AOM. Subsequent treatment with LUT results in the reduction of the tumor markers was recorded. The expressions of MMP-9 and MMP-2 were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence methods. The expressions of MMP-9 and MMP-2 were increased during AOM induction and upon treatment with LUT reduced the expressions. RT-PCR analysis of tissue inhibitor of matrix metalloproteinase (TIMP)-2 was limited during AOM-induced colorectal cancer (CRC). Supplementation of LUT increased the expression of TIMP-2. To conclude, LUT acts as an antimetastatic agent by suppressing MMP-9 and MMP-2 productions and upregulating TIMP-2 expression, thereby suggesting that LUT can be a chemotherapeutic agent against CRC. © The Author(s) 2014.

  19. Cordycepin inhibits LPS-induced inflammatory and matrix degradation in the intervertebral disc

    Directory of Open Access Journals (Sweden)

    Yan Li

    2016-05-01

    Full Text Available Cordycepin is a component of the extract obtained from Cordyceps militaris and has many biological activities, including anti-cancer, anti-metastatic and anti-inflammatory effects. Intervertebral disc degeneration (IDD is a degenerative disease that is closely related to the inflammation of nucleus pulposus (NP cells. The effect of cordycepin on NP cells in relation to inflammation and degeneration has not yet been studied. In our study, we used a rat NP cell culture and an intervertebral disc (IVD organ culture model to examine the inhibitory effects of cordycepin on lipopolysaccharide (LPS-induced gene expression and the production of matrix degradation enzymes (MMP-3, MMP-13, ADAMTS-4, and ADAMTS-5 and oxidative stress-associated factors (nitric oxide and PGE2. We found a protective effect of cordycepin on NP cells and IVDs against LPS-induced matrix degradation and macrophage infiltration. In addition, western blot and luciferase assay results demonstrated that pretreatment with cordycepin significantly suppressed the LPS-induced activation of the NF-κB pathway. Taken together, the results of our research suggest that cordycepin could exert anti-inflammatory and anti-degenerative effects on NP cells and IVDs by inhibiting the activation of the NF-κB pathway. Therefore, cordycepin may be a potential treatment for IDD in the future.

  20. Extracellular matrix-induced gene expression in human breast cancer cells.

    Science.gov (United States)

    Garamszegi, Nandor; Garamszegi, Susanna P; Shehadeh, Lina A; Scully, Sean P

    2009-03-01

    Extracellular matrix (ECM) molecules modify gene expression through attachment-dependent (focal adhesion-related) integrin receptor signaling. It was previously unknown whether the same molecules acting as soluble peptides could generate signal cascades without the associated mechanical anchoring, a condition that may be encountered during matrix remodeling and degradation and relevant to invasion and metastatic processes. In the current study, the role of ECM ligand-regulated gene expression through this attachment-independent process was examined. It was observed that fibronectin, laminin, and collagen type I and II induce Smad2 activation in MCF-10A and MCF-7 cells. This activation is not caused by transforming growth factor (TGF)-beta ligand contamination or autocrine TGF involvement and is 3- to 5-fold less robust than the TGF-beta1 ligand. The resulting nuclear translocation of Smad4 in response to ECM ligand indicates downstream transcriptional responses occurring. Coimmunoprecipitation experiments determined that collagen type II and laminin act through interaction with integrin alpha(2)beta(1) receptor complex. The ECM ligand-induced Smad activation (termed signaling crosstalk) resulted in cell type and ligand-specific transcriptional changes, which are distinct from the TGF-beta ligand-induced responses. These findings show that cell-matrix communication is more complex than previously thought. Soluble ECM peptides drive transcriptional regulation through corresponding adhesion and non-attachment-related processes. The resultant gene expressional patterns correlate with pathway activity and not by the extent of Smad activation. These results extend the complexity and the existing paradigms of ECM-cell communication to ECM ligand regulation without the necessity of mechanical coupling.

  1. RAGE-mediated extracellular matrix proteins accumulation exacerbates HySu-induced pulmonary hypertension.

    Science.gov (United States)

    Jia, Daile; He, Yuhu; Zhu, Qian; Liu, Huan; Zuo, Caojian; Chen, Guilin; Yu, Ying; Lu, Ankang

    2017-05-01

    Extracellular matrix (ECM) proteins accumulation contributes to the progression of pulmonary arterial hypertension (PAH), a rare and fatal cardiovascular condition defined by high pulmonary arterial pressure, whether primary, idiopathic, or secondary to other causes. The receptor for advanced glycation end products (RAGE) is constitutively expressed in the lungs and plays an important role in ECM deposition. Nonetheless, the mechanisms by which RAGE mediates ECM deposition/formation in pulmonary arteries and its roles in PAH progression remain unclear. Expression of RAGE and its activating ligands, S100/calgranulins and high mobility group box 1 (HMGB1), were increased in both human and mouse pulmonary arterial smooth muscle cells (PASMCs) under hypoxic conditions and were also strikingly upregulated in pulmonary arteries in hypoxia plus SU5416 (HySu)-induced PAH in mice. RAGE deletion alleviated pulmonary arterial pressure and restrained extracellular matrix accumulation in pulmonary arteries in HySu-induced PAH murine model. Moreover, blocking RAGE activity with a neutralizing antibody in human PASMCs, or RAGE deficiency in mouse PASMCs exposed to hypoxia, suppressed the expression of fibrotic proteins by reducing TGF-β1 expression. RAGE reconstitution in deficient mouse PASMCs restored hypoxia-stimulated TGF-β1 production via ERK1/2 and p38 MAPK pathway activation and subsequently increased ECM protein expression. Interestingly, HMGB1 acting on RAGE, not toll-like receptor 4 (TLR4), induced ECM deposition in PASMCs. Finally, in both idiopathic PAH patients and HySu-induced PAH mice, soluble RAGE (sRAGE) levels in serum were significantly elevated compared to those in controls. Activation of RAGE facilitates the development of hypoxia-induced pulmonary hypertension by increase of ECM deposition in pulmonary arteries. Our results indicate that sRAGE may be a potential biomarker for PAH diagnosis and disease severity, and that RAGE may be a promising target for

  2. Histological analysis of acute toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Zodrow, Jeanmarie M.; Stegeman, John J.; Tanguay, Robert L

    2004-01-07

    Previous studies have demonstrated that acute exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by injection leads to inhibition of caudal fin regeneration in zebrafish. Since the TCDD exposure in these studies is systemic, it is possible that pathology in organs other than the fin could result in inhibition of fin regeneration. Therefore, histopathology of adult zebrafish (Danio rerio) organs was characterized following abdominal cavity injection of a TCDD dose (70 ng/g). The most pronounced histopathologic changes 5 days post-injection included lipidosis and hypertrophy of liver hepatocytes and hypertrophy of gill lamellae. Effects of TCDD exposure on immunolocalization of the zebrafish aryl hydrocarbon receptor nuclear translocator (ARNT2), the heterodimer partner of the aryl hydrocarbon receptor (AHR2), and an AHR regulated gene cytochrome P450 1A (CYP1A) was also determined. ARNT2 was immunolocalized to the gastrointestinal tract, gill lamellae, kidney, ventricle of the heart, caudal fin, brain and liver of zebrafish. TCDD exposure had no measurable effect on ARNT2 abundance or localization. CYP1A was immunolocalized in TCDD exposed fish as a biomarker for cells with an activated AHR pathway. CYP1A was not detected in any tissue from vehicle exposed fish. Significant TCDD-dependent induction of CYP1A was detected in the proximal tubules of the kidney, in liver hepatocytes and in the gastrointestinal tract of TCDD exposed fish. Significant but lower TCDD-dependent CYP1A expression was evident in the gill, caudal fin and ventricle of the heart. Overall, TCDD exposure in adult zebrafish leads to histopathology similar to that reported in other fish species, and it appears unlikely that the histopathology in these organs completely explains the inhibition of fin regeneration.

  3. Histological analysis of acute toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in zebrafish

    International Nuclear Information System (INIS)

    Zodrow, Jeanmarie M.; Stegeman, John J.; Tanguay, Robert L.

    2004-01-01

    Previous studies have demonstrated that acute exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) by injection leads to inhibition of caudal fin regeneration in zebrafish. Since the TCDD exposure in these studies is systemic, it is possible that pathology in organs other than the fin could result in inhibition of fin regeneration. Therefore, histopathology of adult zebrafish (Danio rerio) organs was characterized following abdominal cavity injection of a TCDD dose (70 ng/g). The most pronounced histopathologic changes 5 days post-injection included lipidosis and hypertrophy of liver hepatocytes and hypertrophy of gill lamellae. Effects of TCDD exposure on immunolocalization of the zebrafish aryl hydrocarbon receptor nuclear translocator (ARNT2), the heterodimer partner of the aryl hydrocarbon receptor (AHR2), and an AHR regulated gene cytochrome P450 1A (CYP1A) was also determined. ARNT2 was immunolocalized to the gastrointestinal tract, gill lamellae, kidney, ventricle of the heart, caudal fin, brain and liver of zebrafish. TCDD exposure had no measurable effect on ARNT2 abundance or localization. CYP1A was immunolocalized in TCDD exposed fish as a biomarker for cells with an activated AHR pathway. CYP1A was not detected in any tissue from vehicle exposed fish. Significant TCDD-dependent induction of CYP1A was detected in the proximal tubules of the kidney, in liver hepatocytes and in the gastrointestinal tract of TCDD exposed fish. Significant but lower TCDD-dependent CYP1A expression was evident in the gill, caudal fin and ventricle of the heart. Overall, TCDD exposure in adult zebrafish leads to histopathology similar to that reported in other fish species, and it appears unlikely that the histopathology in these organs completely explains the inhibition of fin regeneration

  4. Lib, transcriptionally induced in senile plaque-associated astrocytes, promotes glial migration through extracellular matrix.

    Science.gov (United States)

    Satoh, Kazuki; Hata, Mitsumi; Shimizu, Tomoko; Yokota, Hiroshi; Akatsu, Hiroyasu; Yamamoto, Takayuki; Kosaka, Kenji; Yamada, Tatsuo

    2005-09-23

    In an effort to identify astrocyte-derived molecules that may be intimately associated with progression of Alzheimer's disease (AD), Lib, a type I transmembrane protein belonging to leucine-rich repeat superfamily, has been identified as a distinctly inducible gene, responsive to beta-amyloid as well as pro-inflammatory cytokines in astrocytes. To evaluate the roles of Lib in AD, we investigated Lib expression in AD brain. In non-AD brain, Lib mRNA has been detected in neurons but not in quiescent astrocytes. On the contrary, in AD brain, Lib mRNA is expressed in activated astrocytes associated with senile plaques, but not expressed in neurons around lesions. Lib-expressing glioma cells displayed promotion of migration ability through reconstituted extracellular matrix and recombinant Lib protein bound to constituents of extracellular matrix. These observations suggest that Lib may contribute to regulation of cell-matrix adhesion interactions with respect to astrocyte recruitment around senile plaques in AD brain.

  5. 2,3,7,8-Tetrachlorodibenzo-p-dioxin induces apoptotic cell death and cytochrome P4501A expression in developing Fundulus heteroclitus embryos

    Science.gov (United States)

    Toomey, B.H.; Bello, S.; Hahn, M.E.; Cantrell, S.; Wright, P.; Tillitt, D.E.; Di Giulio, R.T.

    2001-01-01

    Fundulus heteroclitus embryos were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during early development using nanoinjection or water bath exposure. TCDD caused developmental abnormalities that included hemorrhaging, loss of vascular integrity, edema, stunted development and death. The LC50 and LD50 of TCDD for Fundulus embryos were ???19.7??9.5 pg TCDD/??l (water bath) and 0.25??0.09 ng TCDD/g embryo (nanoinjection). To identify a possible cause for these developmental abnormalities we analyzed the effects of TCDD on apoptotic cell death and cytochrome P4501A (CYP1A) expression in the embryos. TCDD exposure increased apoptotic cell death in several tissues including brain, eye, gill, kidney, tail, intestine, heart, and vascular tissue. CYP1A expression was also increased in the TCDD-exposed embryos predominantly in liver, kidney, gill, heart, intestine, and in vascular tissues throughout the embryo. There was co-occurrence of TCDD-induced apoptosis and CYP1A expression in some, but not all, cell types. In addition the dose response relationships for apoptosis and mortality were similar, while CYP1A expression appeared more sensitive to TCDD induction. Copyright ?? 2001 Elsevier Science B.V.

  6. Modified permeability modeling of coal incorporating sorption-induced matrix shrinkage

    Science.gov (United States)

    Soni, Aman

    The variation in the cleat permeability of coalbed methane (CBM) reservoirs is attributed primarily to two cardinal processes, with opposing effects. Increase in effective stresses with reduction in pore pressure tends to decrease the cleat permeability, whereas the sorption-induced coal matrix shrinkage actuates reduction in the effective stresses which increases the reservoir permeability. The net effect of the two processes determines the pressure-dependent-permeability and, hence, the overall trend of CBM production with depletion. Several analytical models have been developed and used to predict the dynamic behavior of CBM reservoir permeability during production through pressure depletion, all based on combining the two effects. The purpose of this study was to introduce modifications to two most commonly used permeability models, namely the Palmer and Mansoori, and Shi and Durucan, for permeability variation and evaluate their performance when projecting gas production. The basis for the modification is the linear relationship between the volume of sorbed gas and the associated matrix shrinkage. Hence, the impact of matrix shrinkage is incorporated as a function of the amount of gas produced, or that remaining in coal, at any time during production. Since the exact production from a reservoir is known throughout its life, this significantly simplifies the process of permeability modeling. Furthermore, the modification is also expected to streamline the process of modeling by classifying the shrinkage parameters for coals of different regions, but with similar characteristics. A good analogy is the San Juan basin, where sorption characteristics of coal are so well understood and defined that operators no longer carry out laboratory sorption work. The goal is to achieve the same for incorporation of the matrix shrinkage behavior. Another modification is to incorporate the matrix, or grain, compressibility effect of coal as a correction factor in the Shi and

  7. Radiation-induced myosin IIA expression stimulates collagen type I matrix reorganization.

    Science.gov (United States)

    Blockhuys, Stéphanie; Van Rompaye, Bart; De Rycke, Riet; Lambein, Kathleen; Claes, Kathleen; Bracke, Marc; De Wagter, Carlos; De Wever, Olivier

    2013-07-01

    Extracellular matrix (ECM) reorganization critically contributes to breast cancer (BC) progression and radiotherapy response. We investigated the molecular background and functional consequences of collagen type I (col-I) reorganization by irradiated breast cancer cells (BCC). Radiation-induced (RI) col-I reorganization was evaluated for MCF-7/6, MCF-7/AZ, T47D and SK-BR-3 BCC. Phase-contrast microscopy and a stressed matrix contraction assay were used for visualization and quantification of col-I reorganization. Cell-matrix interactions were assessed by the inhibition of β1 integrin (neutralizing antibody 'P5D2') or focal adhesion kinase (FAK; GSK22560098 small molecule kinase inhibitor). The role of the actomyosin cytoskeleton was explored by western blotting analysis of myosin II expression and activity; and by gene silencing of myosin IIA and pharmacological inhibition of the actomyosin system (blebbistatin, cytochalasin D). BCC death was evaluated by propidium iodide staining. We observed a radiation dose-dependent increase of col-I reorganization by BCC. β1 Integrin/FAK-mediated cell-matrix interactions are essential for RI col-I reorganization. Irradiated BCC are characterized by increased myosin IIA expression and myosin IIA-dependent col-I reorganization. Moreover, RI col-I reorganization by BCC is associated with decreased BCC death, as suggested by pharmacological targeting of the β1 integrin/FAK/myosin IIA pathway. Our data indicate the role of myosin IIA in col-I reorganization by irradiated BCC and reciprocal BCC death. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Incorporation of biomimetic matrix molecules in PEG hydrogels enhances matrix deposition and reduces load-induced loss of chondrocyte-secreted matrix.

    Science.gov (United States)

    Roberts, Justine J; Nicodemus, Garret D; Giunta, Suzanne; Bryant, Stephanie J

    2011-06-01

    Poly(ethylene glycol) (PEG) hydrogels offer numerous advantages in designing controlled 3D environments for cartilage regeneration, but offer little biorecognition for the cells. Incorporating molecules that more closely mimic the native tissue may provide key signals for matrix synthesis and may also help in the retention of neotissue, particularly when mechanical stimulation is employed. Therefore, this research tested the hypothesis that exogenous hyaluronan encapsulated within PEG hydrogels improves tissue deposition by chondrocytes, while the incorporation of Link-N (DHLSDNYTLDHDRAIH), a fragment of link protein that is involved in stabilizing hyaluronan and aggrecan in cartilage, aids in the retention of the entrapped hyaluronan as well as cell-secreted glycosaminoglycans (GAGs), particularly when dynamic loading is employed. The incorporation of Link-N as covalent tethers resulted in a significant reduction, ~60%, in the loss of entrapped exogenous hyaluronan under dynamic stimulation. When chondrocytes were encapsulated in PEG hydrogels containing exogenous hyaluronan and/or Link-N, the extracellular matrix (ECM) analogs aided in the retention of cell-secreted GAGs under loading. The presence of hyaluronan led to enhanced deposition of collagen type II and aggrecan. In conclusion, our results highlight the importance of ECM analogs, specifically hyaluronan and Link-N, in matrix retention and matrix development and offer new strategies for designing scaffolds for cartilage regeneration. Copyright © 2011 Wiley Periodicals, Inc.

  9. Pancreatic carcinoma cells induce fibrosis by stimulating proliferation and matrix synthesis of stellate cells.

    Science.gov (United States)

    Bachem, Max G; Schünemann, Marion; Ramadani, Marco; Siech, Marco; Beger, Hans; Buck, Andreas; Zhou, Shaoxia; Schmid-Kotsas, Alexandra; Adler, Guido

    2005-04-01

    Tumor desmoplasia is one of the representative histopathologic findings in ductal pancreatic adenocarcinoma. The aims of this study were to examine the cellular and molecular mechanisms of fibrogenesis associated with pancreatic adenocarcinomas. Immunostainings were performed with human pancreatic adenocarcinomas (n = 27) and tumors induced in nude mice (n = 36) by subcutaneously injecting MiaPaCa2, Panc1, and SW850 with and without pancreatic stellate cells. Matrix-producing cells were isolated from pancreatic adenocarcinomas and compared with pancreatic stellate cells isolated from tissue of chronic pancreatitis. Paracrine stimulation of pancreatic stellate cells by carcinoma cells was studied regarding matrix synthesis (collagen and c-fibronectin on protein and messenger RNA level) and cell proliferation (bromodeoxyuridine incorporation). High numbers of desmin and alpha-smooth muscle actin-positive cells were detected in 26 of 27 pancreatic adenocarcinomas. Intense fibronectin and collagen stainings were associated with these cells. By using cytofilament stainings, gene expression profiling, and morphological examinations, the matrix-producing cells obtained by the outgrowth method from pancreatic adenocarcinomas were identified as pancreatic stellate cells. Supernatants of MiaPaCa2, Panc1, and SW850 cells stimulated proliferation and collagen type I and c-fibronectin synthesis of cultured pancreatic stellate cells. Preincubation of the carcinoma cell supernatants with neutralizing antibodies against fibroblast growth factor 2, transforming growth factor beta 1, and platelet-derived growth factor significantly reduced the stimulatory effects. Subcutaneous injection of carcinoma cells and pancreatic stellate cells induced fast-growing subcutaneous fibrotic tumors in nude mice. Morphometric analysis of carcinoma cells (cytokeratin stainings) showed a high density of carcinoma cells in these tumors. Pancreatic stellate cells strongly support tumor growth in the

  10. HIV-1-infected macrophages induce astrogliosis by SDF-1α and matrix metalloproteinases

    International Nuclear Information System (INIS)

    Okamoto, Mika; Wang, Xin; Baba, Masanori

    2005-01-01

    Brain macrophages/microglia and astrocytes are known to be involved in the pathogenesis of HIV-1-associated dementia (HAD). To clarify their interaction and contribution to the pathogenesis, HIV-1-infected or uninfected macrophages were used as a model of brain macrophages/microglia, and their effects on human astrocytes in vitro were examined. The culture supernatants of HIV-1-infected or uninfected macrophages induced significant astrocyte proliferation, which was annihilated with a neutralizing antibody to stromal cell-derived factor (SDF)-1α or a matrix metalloproteinase (MMP) inhibitor. In these astrocytes, CXCR4, MMP, and tissue inhibitors of matrix metalloproteinase mRNA expression and SDF-1α production were significantly up-regulated. The supernatants of infected macrophages were always more effective than those of uninfected cells. Moreover, the enhanced production of SDF-1α was suppressed by the MMP inhibitor. These results indicate that the activated and HIV-1-infected macrophages can indirectly induce astrocyte proliferation through up-regulating SDF-1α and MMP production, which implies a mechanism of astrogliosis in HAD

  11. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) promotes lung fibroblast proliferation, survival and differentiation to myofibroblasts.

    Science.gov (United States)

    Hasaneen, Nadia A; Cao, Jian; Pulkoski-Gross, Ashleigh; Zucker, Stanley; Foda, Hussein D

    2016-02-17

    Idiopathic pulmonary fibrosis (IPF) is a chronic progressively fatal disease. Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) is a glycosylated transmembrane protein that induces the expression of some matrix metalloproteinase (MMP) in neighboring stromal cells through direct epithelial-stromal interactions. EMMPRIN is highly expressed in type II alveolar epithelial cells at the edges of the fibrotic areas in IPF lung sections. However, the exact role of EMMPRIN in IPF is unknown. To determine if EMMPRIN contributes to lung fibroblast proliferation, resistance to apoptosis, and differentiation to myofibroblasts, normal Human lung fibroblasts (NHLF) transiently transfected with either EMMPRIN/GFP or GFP were treated with TGF- β1 from 0 to 10 ng/ml for 48 h and examined for cell proliferation (thymidine incorporation), apoptosis (FACS analysis and Cell Death Detection ELISA assay), cell migration (Modified Boyden chamber) and differentiation to myofibroblasts using Western blot for α-smooth actin of cell lysates. The effect of EMMPRIN inhibition on NHLF proliferation, apoptosis, migration and differentiation to myofibroblasts after TGF- β1 treatment was examined using EMMPRIN blocking antibody. We examined the mechanism by which EMMPRIN induces its effects on fibroblasts by studying the β-catenin/canonical Wnt signaling pathway using Wnt luciferase reporter assays and Western blot for total and phosphorylated β-catenin. Human lung fibroblasts overexpressing EMMPRIN had a significant increase in cell proliferation and migration compared to control fibroblasts. Furthermore, EMMPRIN promoted lung fibroblasts resistance to apoptosis. Lung fibroblasts overexpressing EMMPRIN showed a significantly increased expression of α- smooth muscle actin, a marker of differentiation to myofibroblasts compared to control cells. TGF-β1 increased the expression of EMMPRIN in lung fibroblasts in a dose-dependent manner. Attenuation of EMMPRIN expression with the use of an

  12. Total PCBs, TCDD-EQs in eggs: Reproductive hazards to north Pacific albatrosses

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, J.P.; Auman, H.J.; Summer, C.L.; Giesy, J.P.; Sanderson, J.T.; DeDoes, J.M.; Verbrugge, D.A.; Jones, P.

    1995-12-31

    Freshly laid eggs of Laysan and black-footed Albatrosses (Diomedea immutabilis and D. nigripes) were collected at Midway Atoll 1992 through 1994 and subsequently analyzed for chlorinated contaminants including OC pesticides, PCBs, dioxins and furans. TCDD-EQs in eggs were calculated from congener-specific data. Total PCBs ranged from 1.1 to 3.8 mglkg ww. Calculated TCDD-EQs ranged from 52--124 pg/g. A substantial portion (30--35%) of the TCDD-EQs in eggs were owing to dioxins and furans, and the balance to PCBs. PCBs in albatross eggs were much less potent than PCBs from waterbirds` eggs of the Great Lakes and other continental inland waters. Hazard indices based on calculated TCDD-EQs suggested that Laysan eggs were at the LOAEL for embryonic effects, but black-footed eggs were well above avian LOAELS. Egg death during natural incubation was 2--3% greater in black-footed than Laysan nests, and 5% fewer black-footed albatross chicks were fledged in 1994. A low incidence of deformities in hatchlings was noted in 1994 and 1995. Crossed-bill hatchlings were not reported in these populations until the late 1970s in spite of intensive studies 1957--1972, but occurred at rates of 1 in 14,000 hatchlings, and 1 in 300 dead eggs 1993--1995. Reproductive effects owing to contaminant exposures in these most pelagic seabirds are confirmed.

  13. TCDD-MEDIATED OXIDATIVE STRESS IN MALE RAT PUPS FOLLOWING PERINATAL EXPOSURE

    Science.gov (United States)

    TCDD is a highly persistent trace environmental contaminant and is one of the most potent toxicants known to man. Our laboratory has previously reported an increase in the production of reactive oxygen species (ROS) in the brain of female B6C3F1 mice following subchronic exposur...

  14. 2,3,7,8-TCDD exposure, endothelial dysfunction and impaired microvascular reactivity

    Czech Academy of Sciences Publication Activity Database

    Pelclová, D.; Prázdný, M.; Škrha, J.; Fenclová, Z.; Kalousová, M.; Urban, P.; Navrátil, Tomáš; Šenholdová, Z.; Šmerhovský, Z.

    2007-01-01

    Roč. 26, - (2007), s. 705-713 ISSN 0960-3271 Institutional research plan: CEZ:AV0Z40400503 Keywords : 2,3,7,8-TCDD * endothelial dysfunction * oxidative stress * superoxide dismutase Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.335, year: 2007

  15. Prevotella intermedia induces matrix metalloproteinase-9 expression in human periodontal ligament cells.

    Science.gov (United States)

    Guan, Su-Min; Shu, Lei; Fu, Shan-Min; Liu, Bin; Xu, Xiu-Li; Wu, Jun-Zheng

    2008-06-01

    Matrix metalloproteinases (MMPs) play pivotal roles in inflammatory diseases including chronic periodontitis. The effects of Prevotella intermedia, a major periodontal pathogen, on MMP-9 production in primary human periodontal ligament (hPDL) cells were examined in the present study. MMP-9 mRNA expression was measured by semiquantitative reverse transcriptase PCR and its protein secretion was assayed by gelatin zymography. Prevotella intermedia ATCC 25611 supernatant time and dose-dependently induced MMP-9 expression. In contrast, Porphyromanas gingivalis ATCC 33277 supernatants, Escherichia coli lipopolysacchride and IL-1beta exhibited no stimulatory effects on MMP-9 production in hPDL cells. Mitogen-activated protein kinases [MAPK, including extracellular signal-related kinases (ERK), c-jun N-terminal kinases (JNK) and p38] inhibitors exerted no effect on the P. intermedia-induced MMP-9 production, indicating that P. intermedia induced MMP-9 production through an MAPK-independent pathway. Our results demonstrated that P. intermedia may contribute to periodontal tissue destruction during chronic periodontitis by inducing MMP-9 production in hPDL cells.

  16. Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during lake trout early life stage development

    International Nuclear Information System (INIS)

    Walker, M.K.; Peterson, R.E.; Spitsbergen, J.M.; Olson, J.R.

    1990-01-01

    The presence of halogenated aromatic hydrocarbons has been proposed to explain early life stage mortality seen in lake trout (Salvelinus namaycush) from the Great Lakes. Three years of experiments show that lake trout sac fry are extremely sensitive to TCDD. Newly fertilized lake trout eggs exposed to vehicle or graded water concentrations of 3 H-TCDD for 48 hr accumulated 0, 40, 55, 60, 70, 110, 150, 170, 280, 370 or 530 ppt (pg 3 H-TCDD/g egg). The 3 H-TCDD persisted in the egg and sac fry stages (t 1/2 = 349 days), but was rapidly eliminated in the fry stage (t 1/2 =40 days). Egg stage mortality was unaffected by TCDD (11%, mean); however, at the onset of hatching there was a dose-related increase in larvae dying half-hatched. The greatest dose-related mortality occurred in the sac fry stage and was associated with subcutaneous edema of the yolk sac membrane and hemorrhages, morphologically resembling blue-sac disease. Cumulative mortality at swim up was 19% (vehicle), 20-28% (40-60), 45% (70), 74% (110), and 100% (≥150 ppt 3 H-TCDD). The LD 50 in sac fry based on the 3 H-TCDD egg burden was 75 ppt (71-77 ppt, 95% C.I.)

  17. Ramipril inhibits AGE-RAGE-induced matrix metalloproteinase-2 activation in experimental diabetic nephropathy.

    Science.gov (United States)

    Fukami, Kei; Yamagishi, Sho-Ichi; Coughlan, Melinda T; Harcourt, Brooke E; Kantharidis, Phillip; Thallas-Bonke, Vicki; Okuda, Seiya; Cooper, Mark E; Forbes, Josephine M

    2014-01-01

    Advanced glycation end products (AGE)-receptor for AGE (RAGE) axis and renin-angiotensin system (RAS) play a role in diabetic nephropathy (DN). Matrix metalloproteinase-2 (MMP-2) activation also contributes to DN. However, the pathological interaction among AGE-RAGE, RAS and MMP-2 in DN remains unknown. We examined here the involvement of AGE and RAS in MMP-2 activation in streptozotocin (STZ)-induced diabetic rats and in AGE-exposed rat renal proximal tubular cells (RPTCs). Experimental diabetes was induced in 6-week-old male Sprague-Dawley (SD) rats by intravenous injection of STZ. Diabetic rats received ramipril (3 mg/kg body weight/day) or vehicle for 32 weeks. AGE-modified rat serum albumin (AGE-RSA) or RSA was intraperitoneally administrated to 6-week-old male SD rats for 16 weeks. RPTCs were stimulated with 100 μg/ml AGE-modified bovine serum albumin (AGE-BSA) or BSA in the presence or absence of 10(-7) M ramiprilat, an inhibitor of angiotensin-converting enzyme or 100 nM BAY11-7082, an IκB-α phosphorylation inhibitor. AGE and RAGE expression levels and MMP-2 activity in the tubules of diabetic rats was significantly increased in association with increased albuminuria, all of which were blocked by ramipril. AGE infusion induced tubular MMP-2 activation and RAGE gene expression in SD rats. Ramiprilat or BAY11-7082 inhibited the AGE-induced MMP-2 activation or reactive oxygen species generation in RPTCs. Angiotensin II increased MMP-2 gene expression in RPTCs, which was blocked by BAY11-7082. Our present study suggests the involvement of AGE-RAGE-induced, RAS-mediated MMP-2 activation in experimental DN. Blockade of AGE-RAGE axis by ramipril may protect against DN partly via suppression of MMP-2.

  18. HMGB1 Induces Secretion of Matrix Vesicles by Macrophages to Enhance Ectopic Mineralization.

    Science.gov (United States)

    Chen, Qiang; Bei, Jun-Jie; Liu, Chuan; Feng, Shi-Bin; Zhao, Wei-Bo; Zhou, Zhou; Yu, Zheng-Ping; Du, Xiao-Jun; Hu, Hou-Yuan

    2016-01-01

    Numerous clinical conditions have been linked to ectopic mineralization (EM). This process of pathological biomineralization is complex and not fully elucidated, but thought to be started within matrix vesicles (MVs). We hypothesized that high mobility group box 1 (HMGB1), a cytokine associated with biomineralizing process under physiological and pathological conditions, induces EM via promoting MVs secretion from macrophages. In this study, we found that HMGB1 significantly promoted secretion of MVs from macrophages and subsequently led to mineral deposition in elevated Ca/Pi medium in vitro. Transmission electron microscopy of calcifying MVs showed formation of hydroxyapatite crystals in the vesicle interior. Subcutaneous injection into mice with MVs derived from HMGB1-treated cells showed a greater potential to initiate regional mineralization. Mechanistic experiments revealed that HMGB1 activated neutral sphingomyelinase2 (nSMase2) that involved the receptor for advanced glycation end products (RAGE) and p38 MAPK (upstream of nSMase2). Inhibition of nSMase2 with GW4869 or p38 MAPK with SB-239063 prevented MVs secretion and mineral deposition. Collectively, HMGB1 induces MVs secretion from macrophages at least in part, via the RAGE/p38 MAPK/nSMase2 signaling pathway. Our findings thus reveal a novel mechanism by which HMGB1 induces ectopic mineralization.

  19. Twinning-induced plasticity (TWIP) and work hardening in Ti-based metallic glass matrix composites.

    Science.gov (United States)

    Fan, J; Qiao, J W; Wang, Z H; Rao, W; Kang, G Z

    2017-05-12

    The present study demonstrates that Ti-based metallic glass matrix composites (MGMCs) with a normal composition of Ti 43 Zr 32 Ni 6 Ta 5 Be 14 containing ductile dendrites dispersed in the glass matrix has been developed, and deformation mechanisms about the tensile property have been investigated by focusing on twinning-induced plasticity (TWIP) effect. The Ti-based MGMC has excellent tensile properties and pronounced tensile work-hardening capacity, with a yield strength of 1100 MPa and homogeneous elongation of 4%. The distinguished strain hardening is ascribed to the formation of deformation twinning within the dendrites. Twinning generated in the dendrites works as an obstacle for the rapid propagation of shear bands, and then, the localized necking is avoided, which ensures the ductility of such kinds of composites. Besides, a finite-element model (FEM) has been established to explain the TWIP effect which brings out a work-hardening behavior in the present MGMC instead of a localized strain concentration. According to the plasticity theory of traditional crystal materials and some new alloys, TWIP effect is mainly controlled by stacking fault energy (SFE), which has been analyzed intensively in the present MGMC.

  20. Inhibition of matrix metalloproteins 9 attenuated Candida albicans induced inflammation in mouse cornea.

    Science.gov (United States)

    Dong, C; Yang, M G

    2016-10-31

    Since the severe corneal ulceration of mouse cornea is known to occur with inflammation. As one of imperative matrix metalloproteinase, the potential roles of matrix metalloproteins 9 (MMP9) in corneal ulceration and keratitis are still unveiled caused by fungal invasion. In this study, Candida albicans (CA) inoculated wild-type KM mice cornea was used as a model pathogen in corneal inflammation.  CA invasion significantly stimulated the expression of collagen IV and MMP9 detected by RT-PCR, Real-time PCR and Immunofluorescent staining in mouse cornea as soon as 6 hours post infection, and relatively decreased at 1 day post infection. For examining the role of MMP9 in fungal keratitis, the mice corneas were subconjunctivally injected MMP9 antibody or recombinant MMP9 protein 6 hours prior to CA inoculation, using rabbit IgG as control. Subconjunctival injection of recombinant MMP9 protein prior to CA inoculation enhanced, whereas MMP9 antibody attenuated corneal ulceration and inflammation, examining basement membrane, fungal load, myeloperoxidase (MPO) and proinflammatory cytokines including Macrophage inflammatory protein 2 (MIP2), Interleukin-1β (IL-1β) and Tumor necrosis factor-α (TNF-α). Inhibition of MMP9 could potentially attenuate Candida albicans induced inflammation in mouse cornea.

  1. Craniofacial form is altered by chronic adult exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD in Han/Wistar and Long–Evans rats with different aryl hydrocarbon receptor (AhR structures

    Directory of Open Access Journals (Sweden)

    Sabrina B. Sholts

    2015-01-01

    Full Text Available Mammalian bone has shown a variety of responses to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD exposure in experimental and wildlife studies. Although many responses have been well characterized in the postcranial skeleton, dioxin-induced effects on the cranium are largely unknown. In this study, we investigated the effects of chronic adult exposure to TCDD on cranial size and shape in dioxin-resistant Han/Wistar (H/W and dioxin-sensitive Long–Evans (L–E rat strains. Three-dimensional landmark configurations for the face, vault, and base of the cranium were recorded and analyzed using geometric morphometrics (GM and dose–response modeling. The strongest effects were shown by L–E and H/W rats with daily exposures of 100 and 1000 ng TCDD/kg bw/day, respectively, resulting in significant reductions in centroid size (CS in all three cranial modules for both strains except for the vault in H/W rats. Consistent with previous evidence of intraspecific variation in TCDD resistance, the benchmark doses (CEDs for cranial size reduction in L–E rats were roughly 10-fold lower than those for H/W rats. For both strains, the face showed the greatest size reduction from the highest doses of TCDD (i.e., 3.6 and 6.3% decreases in H/W and L–E rats, respectively, most likely related to dose-dependent reductions in limb bone size and body weight gain. However, intrinsic morphological differences between strains were also observed: although the control groups of H/W and L–E rats had vaults and bases of comparable size, the face was 6.4% larger in L–E rats. Thus, although H/W rats possess an altered aryl hydrocarbon receptor (AhR that appears to mediate and provides some resistance to TCDD exposure, their smaller reductions in facial size may also relate to strain-specific patterns of cranial development and growth. Future research will be aimed at understanding how ontogenetic factors may modulate toxic effects of prenatal and lactational exposure on

  2. Experimental Analysis of Flow-Induced Matrix Deformation on Deviation from Darcy's Law in Deformable Porous Media

    Science.gov (United States)

    Munro, Benjamin; Becker, Sid

    2017-11-01

    When a viscous fluid flows through a deformable porous medium, the response of the matrix and the flow field is coupled. The flow of the fluid through the elastic media causes matrix deformation and conversely, deformation of the matrix affects the fluid field by altering pressure within the pores. This study concerns the effect of flow-induced matrix deformation on deviation from Darcy's law at low Reynolds numbers in a deformable porous medium. The experiments consist of a glycerol and water mixture driven through an isotropic elastic porous matrix by an externally applied pressure gradient. The method of elastic matrix manufacture allows for a particular control of the matrix parameters: elasticity and pore geometry. The coupled solid-fluid interaction is then observed in an experimental test rig which captures the global flow behaviour, matrix deformation, and the onset of deviation from Darcy's law at low Re. The experimental data is then compared against theoretical and computational models, and presented so that the results can be used for numerical validation.

  3. Feasibility of arthroscopic placement of autologous matrix-induced chondrogenesis grafts in the cadaver hip joint

    Directory of Open Access Journals (Sweden)

    Fritz Thorey

    2013-09-01

    Full Text Available An assortment of clinical trials have been done presenting the effectiveness of autologous matrix-induced chondrogenesis (AMIC for the regeneration of chondral leasions. The purpose of the study was to underline the accessability of the acetabulum and the femoral head through the known portals and prove i the feasibility of placing the AMIC in the different zones of the hip joint and ii check for dislocation after joint movement. Six human cadavers underwent hip arthroscopy on both hips. Two chondral lesions were set on each femoral head and two in the acetabulum to evaluate a total of 48 defects. After microfracturing an autologous matrix-induced chondrogenesis graft was placed on these lesions arthroscopically. After repeated joint movement the dislocation of the graft was checked. It was possible to place the AMIC graft in all 48 chondral lesions. The time needed for placing the graft was 8±2.9 minutes. A trend of time reduction could be detected throughout this study as the surgeon gained more experience. For the femoral head, after twenty cycles of joint movement 18/24 spots showed no displacement, 4/24 showed minor displacement (<3 mm and 2/24 showed major displacement (>3 mm. None showed total displacement. For the acetabulum 22/24 spots showed no displacement and 2/24 showed minor displacement. A combined microfracturing and placing of an AMIC graft of focal chondral lesions of the hip joint can be done arthroscopically. Prospective randomized in vivo studies should compare the results of arthroscopilally placed AMIC grafts with microfracturing and microfracturing alone.

  4. Phosphate induces formation of matrix vesicles during odontoblast-initiated mineralization in vitro.

    Science.gov (United States)

    Chaudhary, Sandeep C; Kuzynski, Maria; Bottini, Massimo; Beniash, Elia; Dokland, Terje; Mobley, Callie G; Yadav, Manisha C; Poliard, Anne; Kellermann, Odile; Millán, José Luis; Napierala, Dobrawa

    2016-01-01

    Mineralization is a process of deposition of calcium phosphate crystals within a fibrous extracellular matrix (ECM). In mineralizing tissues, such as dentin, bone and hypertrophic cartilage, this process is initiated by a specific population of extracellular vesicles (EV), called matrix vesicles (MV). Although it has been proposed that MV are formed by shedding of the plasma membrane, the cellular and molecular mechanisms regulating formation of mineralization-competent MV are not fully elucidated. In these studies, 17IIA11, ST2, and MC3T3-E1 osteogenic cell lines were used to determine how formation of MV is regulated during initiation of the mineralization process. In addition, the molecular composition of MV secreted by 17IIA11 cells and exosomes from blood and B16-F10 melanoma cell line was compared to identify the molecular characteristics distinguishing MV from other EV. Western blot analyses demonstrated that MV released from 17IIA11 cells are characterized by high levels of proteins engaged in calcium and phosphate regulation, but do not express the exosomal markers CD81 and HSP70. Furthermore, we uncovered that the molecular composition of MV released by 17IIA11 cells changes upon exposure to the classical inducers of osteogenic differentiation, namely ascorbic acid and phosphate. Specifically, lysosomal proteins Lamp1 and Lamp2a were only detected in MV secreted by cells stimulated with osteogenic factors. Quantitative nanoparticle tracking analyses of MV secreted by osteogenic cells determined that standard osteogenic factors stimulate MV secretion and that phosphate is the main driver of their secretion. On the molecular level, phosphate-induced MV secretion is mediated through activation of extracellular signal-regulated kinases Erk1/2 and is accompanied by re-organization of filamentous actin. In summary, we determined that mineralization-competent MV are distinct from exosomes, and we identified a new role of phosphate in the process of ECM

  5. Insulin sensitivity and serum TCDD in Air Force veterans occupationally exposed to herbicides during the Vietnam war

    Energy Technology Data Exchange (ETDEWEB)

    Kern, P.; Said, S. [Univ. of Arkansas for Medical Sciences, Little Rock (United States); Jackson, W. Jr; Michalek, J. [Air Force Research Lab., San Antonio (United States)

    2004-09-15

    Between 1961 and 1971, the United States Air Force sprayed 12 million gallons of the defoliant ''Agent Orange'' on 3.6 million acres of Vietnam. Agent Orange was a 1:1 mixture of 2,4-dichlorophenoxyacetic acid and 2,4,5- trichlorophenoxyacetic acid, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was a contaminant of the defoliant, from less than 0.05 to almost 50 parts per million. Numerous Vietnam veterans were exposed to TCDD when Agent Orange and other TCDD-contaminated herbicides were sprayed in large quantities in Vietnam and TCDD has been found at many toxic waste disposal sites in the United States. Some of the highest exposure to TCDD occurred in members of Operation Ranch Hand, the Air Force unit responsible for spraying herbicides from fix-wing aircraft in Vietnam. The Air Force Health Study (AFHS), an epidemiological study of Ranch Hand veterans, was launched in 1980 to address veteran concerns regarding Agent Orange exposure. A link between TCDD and diabetes has been demonstrated in several studies. Among the Ranch Hand veterans with high blood levels of TCDD, there was a significant increase in the prevalence of diabetes and a decrease in the age at which diabetes was diagnosed. In a study from Seveso, Italy, where 45,000 people had varying levels of exposure to TCDD, there were significant increases in mortality from coronary artery disease and diabetes. Several studies have demonstrated a relationship between blood TCDD levels and hyperinsulinemia. The data suggest that non-diabetic individuals exposed to TCDD have an increased risk of insulin-resistance, being able to maintain normal blood glucose levels but only because of very high concentrations of insulin. As a result of available evidence, public policy decisions have been made, such as a decision by the Veterans Administration that diabetes is a service-connected condition in Agent Orange-exposed Vietnam veterans. Here we study the relation between TCDD insulin sensitivity

  6. Creep and stress relaxation induced by interface diffusion in metal matrix composites

    Science.gov (United States)

    Li, Yinfeng; Li, Zhonghua

    2013-03-01

    An analytical solution is developed to predict the creep rate induced by interface diffusion in unidirectional fiber-reinforced and particle reinforced composites. The driving force for the interface diffusion is the normal stress acting on the interface, which is obtained from rigorous Eshelby inclusion theory. The closed-form solution is an explicit function of the applied stress, volume fraction and radius of the fiber, as well as the modulus ratio between the fiber and the matrix. It is interesting that the solution is formally similar to that of Coble creep in polycrystalline materials. For the application of the present solution in the realistic composites, the scale effect is taken into account by finite element analysis based on a unit cell. Based on the solution, a closed-form solution is also given as a description of stress relaxation induced by interfacial diffusion under constant strain. In addition, the analytical solution for the interface stress presented in this study gives some insight into the relationship between the interface diffusion and interface slip. This work was supported by the financial support from the Nature Science Foundation of China (No. 10932007), the National Basic Research Program of China (No. 2010CB631003/5), and the Doctoral Program of Higher Education of China (No. 20100073110006).

  7. Assessment of thermal shock induced damage in silicon carbide fibre reinforced glass matrix composites

    Directory of Open Access Journals (Sweden)

    Boccaccini, A. R.

    1998-09-01

    Full Text Available The development of microstructural damage in silicon carbide fibre (Nicalon™ reinforced glass matrix composite samples subjected to thermal shock was investigated by using a nondestructive forced resonance technique and fibre push out indentation tests. Thermal shock testing involved quenching samples in a water bath maintained at room temperature from a high temperature (650ºC. Changes in the Young's modulus and internal friction of the samples with increasing number of shocks were measured accurately by the forced resonance technique. Fibre push-out tests showed no significant changes in the properties of the fibre-matrix interface, indicating that damage in the composite was concentrated mainly in the development of matrix microcracking. It was also shown that the internal friction is a very sensitive parameter by which to detect the onset and development of such microcracking. A simple semi-empirical model is proposed to correlate the internal friction level with the microcracking density in the glass matrix. Finally, the relevance of detecting nondestructively the existence of microcracks in the glass matrix, before any significant interfacial degradation occurs, is emphasized, in conextion with the possibility of inducing a crack healing process by a thermal treatment (annealing, taking advantage of the viscous flow properties of the glass.

    El desarrollo de daño microestructural en materiales compuestos de matriz de vidrio reforzados con fibras de carburo de silicio (Nicalon™ sometidos a choque térmico fue investigado mediante la técnica no-destructiva de resonancia forzada y por mediciones de indentación "push-out" de fibras. Los ensayos de choque térmico involucraron el enfriamiento brusco en un baño de agua a temperatura ambiente de las piezas previamente calentadas a una temperatura elevada (650ºC. La técnica de resonancia forzada permitió medir cambios en el módulo de Young de elasticidad y en la fricci

  8. Breast cancer normalization induced by embryonic mesenchyme is mediated by extracellular matrix biglycan.

    Science.gov (United States)

    Bischof, Ashley G; Yüksel, Deniz; Mammoto, Tadanori; Mammoto, Akiko; Krause, Silva; Ingber, Donald E

    2013-08-01

    Some epithelial cancers can be induced to revert to quiescent differentiated tissue when combined with embryonic mesenchyme; however, the mechanism of this induction is unknown. Here we combine tissue engineering, developmental biology, biochemistry and proteomics approaches to attack this problem. Using a synthetic reconstitution system, we show that co-culture of breast cancer cells with embryonic mesenchyme from early stage (E12.5-13.5) mammary glands decreases tumor cell proliferation while stimulating acinus differentiation, whereas cancer-associated fibroblasts (CAFs) fail to produce these normalizing effects. When insoluble extracellular matrices (ECMs) were isolated from cultured early stage (E12.5-13.5) embryonic mammary mesenchyme cells or E10 tooth mesenchyme and recombined with mammary tumor cells, they were found to be sufficient to induce breast cancer normalization including enhanced expression of estrogen receptor-α (ER-α). In contrast, ECM from later stage (E14.5) mammary mesenchyme and conditioned medium isolated from mesenchymal cell cultures were ineffective. Importantly, when the inductive ECMs produced by early stage embryonic mammary mesenchyme were scraped from dishes and injected into fast-growing breast tumors in mice, they significantly inhibited cancer expansion. Proteomics analysis of the detergent insoluble ECM material revealed several matrix components that were preferentially expressed in the embryonic ECMs. Analysis of two of these molecules previously implicated in cancer regulation--biglycan and tenascin C--revealed that addition of biglyan can mimic the tumor normalization response, and that siRNA knockdown of its expression in cultured embryonic mesenchyme results in loss of the ECM's inductive activity. These studies confirm that embryonic mesenchyme retains the ability to induce partial breast cancer reversion, and that its inductive capability resides at least in part in the ECM protein biglycan that it produces.

  9. Response of induced bone defects in horses to collagen matrix containing the human parathyroid hormone gene.

    Science.gov (United States)

    Backstrom, Kristin C; Bertone, Alicia L; Wisner, Erik R; Weisbrode, Stephen E

    2004-09-01

    To determine whether human parathyroid hormone (hPTH) gene in collagen matrix could safely promote bone formation in diaphyseal or subchondral bones of horses. 8 clinically normal adult horses. Amount, rate, and quality of bone healing for 13 weeks were determined by use of radiography, quantitative computed tomography, and histomorphometric analysis. Diaphyseal cortex and subchondral bone defects of metacarpi were filled with hPTH(1-34) gene-activated matrix (GAM) or remained untreated. Joints were assessed on the basis of circumference, synovial fluid analysis, pain on flexion, lameness, and gross and histologic examination. Bone volume index was greater for cortical defects treated with hPTH(1-34) GAM, compared with untreated defects. Bone production in cortical defects treated with hPTH(1-34) GAM positively correlated with native bone formation in untreated defects. In contrast, less bone was detected in hPTH(1-34) GAM-treated subchondral bone defects, compared with untreated defects, and histology confirmed poorer healing and residual collagen sponge. Use of hPTH(1-34) GAM induced greater total bone, specifically periosteal bone, after 13 weeks of healing in cortical defects of horses. The hPTH(1-34) GAM impeded healing of subchondral bone but was biocompatible with joint tissues. Promotion of periosteal bone formation may be beneficial for healing of cortical fractures in horses, but the delay in onset of bone formation may negate benefits. The hPTH(1-34) GAM used in this study should not be placed in articular subchondral bone defects, but contact with articular surfaces is unlikely to cause short-term adverse effects.

  10. Demineralized Dentin Matrix Induces Odontoblastic Differentiation of Dental Pulp Stem Cells.

    Science.gov (United States)

    Liu, Guolin; Xu, Guoquan; Gao, Zhenhua; Liu, Zhenhai; Xu, Junji; Wang, Jinsong; Zhang, Chunmei; Wang, Songlin

    2016-01-01

    The aim of this study was to investigate the effect of demineralized dentin matrix (DDM) on dental pulp stem cells (DPSCs) and the potential of complexes with DPSCs and DDM for mineralized tissue formation. Stem cells derived from the dental pulp of healthy pigs aged 18 months were isolated and cultured. DPSCs were incubated with alpha-minimum essential medium treated with DDM extract at 1 mg/ml (DDM1) or 10 mg/ml (DDM10). The concentrations of 3 growth factors in DDM extract was measured by enzyme-linked immunosorbent assay. Adhesion of DPSCs on DDM and hydroxyapatite-tricalcium phosphate (HA-TCP) surfaces was observed using scanning electron microscopy. Cell proliferation was evaluated with cell counting kit-8 and migration by Transwell migration assays. Odontoblastic differentiation was assessed by alkaline phosphatase (ALP) and alizarin red staining, ALP activity and real-time polymerase chain reaction analysis of markers of ALP, runt-related transcription factor 2, type I collagen, dentin matrix acidic phosphoprotein-1, osteonectin and dentin sialophosphoprotein (DSPP). Finally, DPSCs were combined with DDM and placed subcutaneously in nude mice for 12 weeks; DPSCs combined with HA-TCP and DDM alone served as controls. DDM could promote DPSC adhesion, migration and odontoblastic differentiation. Mineralized tissue formation was observed with the DPSC and DDM combination and the DPSC and HA-TCP combination. The mineralized tissue of the DPSC + DDM combination stained positive for DSPP, similar to the dentin tissue. These results indicate that DDM induces DPSC odontoblastic differentiation, suggesting applications for dentin regeneration. © 2015 S. Karger AG, Basel.

  11. Extracellular matrix metalloproteinase inducer expression in the baboon endometrium: menstrual cycle and endometriosis.

    Science.gov (United States)

    Braundmeier, A G; Fazleabas, A T; Nowak, R A

    2010-12-01

    Extracellular matrix metalloproteinase inducer (EMMPRIN; BSG) regulates tissue remodeling through matrix metalloproteinases (MMPs). In human and non-human primates, endometrial remodeling is important for menstruation and the pathogenesis of endometriosis. We hypothesized that as in humans, BSG and MMPs are expressed in the endometrium of cycling baboons, and their expression is hormonally regulated by ovarian hormones, but endometriosis disrupts this regulation. BSG expression was evaluated in the baboon endometrium by q-PCR and immunohistochemistry. In the endometrium of control cycling animals, BSG mRNA levels were highest in late secretory stage tissue. BSG protein localized to glandular epithelial cells during the proliferative phase; whereas, secretory stage tissues expressed BSG in glandular and luminal epithelia with weak stromal staining. Several MMPs were differentially expressed throughout the menstrual cycle with the highest levels found during menstruation. In ovariectomized animals, BSG endometrial mRNA levels were highest with treatment of both estrogen and progesterone than that with only estrogen. Estrogen alone resulted in BSG protein localization primarily in the endometrial glandular epithelia, while estrogen and progesterone treatment displayed BSG protein localization in both the glandular and stromal cells. Exogenous hormone treatment resulted in differential expression patterns of all MMPs compared with the control cycling animals. In the eutopic endometrium of endometriotic animals, BSG mRNA levels and protein were elevated early but decreased later in disease progression. Endometriosis elevated the expression of all MMPs except MMP7 compared with the control animals. In baboons, BSG and MMP endometrial expression is regulated by both ovarian hormones, and their expression patterns are dysregulated in endometriotic animals.

  12. 2,3,7,8-Tetrachlorodibenzo-p-dioxin-mediated disruption of the CD40 ligand-induced activation of primary human B cells

    International Nuclear Information System (INIS)

    Lu Haitian; Crawford, Robert B.; Kaplan, Barbara L.F.; Kaminski, Norbert E.

    2011-01-01

    Suppression of the primary antibody response is particularly sensitive to suppression by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in mice; however, surprisingly little is known concerning the effects of TCDD on humoral immunity or B cell function in humans. Results from a limited number of previous studies, primarily employing in vitro activation models, suggested that human B cell effector function is suppressed by TCDD. The present study sought to extend these findings by investigating, in primary human B cells, the effects of TCDD on several critical stages leading to antibody secretion including activation and plasmacytic differentiation using an in vitro CD40 ligand activation model. These studies revealed important differences in the response of human and mouse B cells to TCDD, the most striking being altered expression of plasmacytic differentiation regulators, B lymphocyte-induced maturation protein 1 and paired box protein 5, in mouse but not human B cells. The activation of human B cells was profoundly impaired by TCDD, as evidenced by decreased expression of activation markers CD80, CD86, and CD69. The impaired activation correlated with decreased cell viability, which prevented the progression of human B cells toward plasmacytic differentiation. TCDD treatment also attenuated the early activation of mitogen-activated protein kinases (MAPK) and Akt signaling in human B cells. Collectively, the present study provided experimental evidence for novel mechanisms by which TCDD impairs the effector function of primary human B cells. - Highlights: → In this study primary human and mouse B cell toxicity to TCDD was compared. → TCDD altered the expression of Blimp-1 and Pax5 in mouse but not human B cells. → TCDD markedly suppressed human B cell activation as characterized by CD80, CD86 and CD69 expression. → TCDD inhibited ERK, p38, and Akt phosphorylation in human B cells.

  13. beta-Catenin signaling is required for TGF-beta(1)-induced extracellular matrix production by airway smooth muscle cells

    NARCIS (Netherlands)

    Baarsma, Hoeke A.; Menzen, Mark H.; Halayko, Andrew J.; Meurs, Herman; Kerstjens, Huib A. M.; Gosens, Reinoud

    2011-01-01

    Baarsma HA, Menzen MH, Halayko AJ, Meurs H, Kerstjens HA, Gosens R. beta-Catenin signaling is required for TGF-beta(1)-induced extracellular matrix production by airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 301: L956-L965, 2011. First published September 9, 2011; doi:

  14. On the thermally-induced residual stresses in thick fiber-thermoplastic matrix (PEEK) cross-ply laminated plates

    Science.gov (United States)

    Hu, Shoufeng; Nairn, John A.

    1992-01-01

    An analytical method for calculating thermally-induced residual stresses in laminated plates is applied to cross-ply PEEK laminates. We considered three cooling procedures: slow cooling (uniform temperature distribution); convective and radiative cooling; and rapid cooling by quenching (constant surface temperature). Some of the calculated stresses are of sufficient magnitude to effect failure properties such as matrix microcracking.

  15. Filtration assay for quantitation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) specific binding to whole cells in culture

    International Nuclear Information System (INIS)

    Dold, K.M.; Greenlee, W.F.

    1990-01-01

    A rapid and sensitive filtration assay for quantitating the specific binding of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to whole cells in culture is described. Cell monolayers are incubated with [3H]TCDD in the presence or absence of excess unlabeled ligand, detached from the culture dish with trypsin, filtered, and washed with cold (-78 degrees C) acetone to separate free and nonspecifically bound TCDD from specifically bound TCDD. TCDD receptor binding parameters were characterized in the murine hepatoma cell line Hepa1c1c7. The lower limit of detection of TCDD specific binding was in a sample equivalent to 10 micrograms of total cell protein. The equilibrium dissociation constant and stereospecificity for binding to the TCDD receptor were the same as those previously reported with other TCDD receptor assays on broken cell preparations. Analysis of binding in the murine hepatoma TCDD receptor variants TAO-c1BPrc1 and BPrc1 indicated that this assay will detect receptor number or affinity variants, but will not detect nuclear transfer deficient variants. The major advantage of the whole cell binding assay is that it provides the means to rapidly and reproducibly quantitate TCDD specific binding in small samples of whole cells in culture. In addition, this method eliminates loss or degradation of the receptor protein during the fractionation of cells required in previously reported methods. This method should prove useful in screening clonal cell populations for TCDD receptor number and affinity variants, and in screening for TCDD receptor binding activity in complementation studies of receptor deficient cells

  16. Increasing extracellular matrix collagen level and MMP activity induces cyst development in polycystic kidney disease

    Directory of Open Access Journals (Sweden)

    Liu Bin

    2012-09-01

    Full Text Available Abstract Background Polycystic Kidney Disease (PKD kidneys exhibit increased extracellular matrix (ECM collagen expression and metalloproteinases (MMPs activity. We investigated the role of these increases on cystic disease progression in PKD kidneys. Methods We examined the role of type I collagen (collagen I and membrane bound type 1 MMP (MT1-MMP on cyst development using both in vitro 3 dimensional (3D collagen gel culture and in vivo PCK rat model of PKD. Results We found that collagen concentration is critical in controlling the morphogenesis of MDCK cells cultured in 3D gels. MDCK cells did not form 3D structures at collagen I concentrations lower than 1 mg/ml but began forming tubules when the concentration reaches 1 mg/ml. Significantly, these cells began to form cyst when collagen I concentration reached to 1.2 mg/ml, and the ratios of cyst to tubule structures increased as the collagen I concentration increased. These cells exclusively formed cyst structures at a collagen I concentration of 1.8 mg/ml or higher. Overexpression of MT1-MMP in MDCK cells significantly induced cyst growth in 3D collagen gel culture. Conversely, inhibition of MMPs activity with doxycycline, a FDA approved pan-MMPs inhibitor, dramatically slowed cyst growth. More importantly, the treatment of PCK rats with doxycycline significantly decreased renal tubule cell proliferation and markedly inhibited the cystic disease progression. Conclusions Our data suggest that increased collagen expression and MMP activity in PKD kidneys may induce cyst formation and expansion. Our findings also suggest that MMPs may serve as a therapeutic target for the treatment of human PKD.

  17. Laser-induced breakdown spectroscopy for the quantitative analysis of metals in sediments using natural zeolite matrix

    Science.gov (United States)

    Austria, E. S.; Fuentes, E. M.; Nuesca, G. M.; Lamorena, R. B.

    2017-10-01

    The dependence of laser-induced breakdown spectroscopy (LIBS) to the matrix of the sample remains an important consideration in performing quantitative analysis. In this study, a new matrix was introduced in the preparation of solid powder calibration curves. Heat-treated natural zeolite and KBr were mixed separately into high purity metal powders to generate calibration curves using a univariate approach. A LIBS technique was used in the detection and quantitative analysis of Cr, Cu and Pb in river sediment samples. The relative percent difference (RPD) was calculated to describe the variability measurements made using ICP/OES and LIBS as well as to evaluate the accuracy of the method. Calculated limits of detection in the matrices prepared were comparable with literature values and ranged from 0.41 to 6.1 ppm. The resulting metal concentrations indicate that the natural zeolite matrix were closer to the reference values compared to the KBr matrix. By employing principal component analysis (PCA), heat treated zeolite was shown as a potential diluent or binder for generating calibration curves and could provide matrix-matched standards in identification of target metals from unknown sediment samples. The natural zeolite appeared to closely simulate the ablation behavior and property of the samples, and it is found to be a potential suitable matrix for the quantitative LIBS analysis of sediments.

  18. Extracellular matrix metalloproteinase inducer (EMMPRIN/CD147) as a novel regulator of myogenic cell differentiation.

    Science.gov (United States)

    Attia, Mohamed; Mohamed, Attia; Huet, Eric; Eric, Huet; Delbé, Jean; Jean, Delbé; Ledoux, Dominique; Dominique, Ledoux; Menashi, Suzanne; Suzanne, Menashi; Martelly, Isabelle; Isabelle, Martelly

    2011-01-01

    Matrix metalloproteinases (MMPs) are thought to play an important role in skeletal muscle cell growth and differentiation. In view of the MMP inducing function of EMMPRIN/CD147, its role in myogenic cell differentiation was investigated. EMMPRIN level increased during differentiation of both rat primary myoblasts derived from satellite cells and mouse C2.7 myogenic cells and was associated with an alteration in its molecular forms. In parallel, expression of pro-MMP-9 gradually decreased and that of pro-MMP-2 and active MMP-2 increased. While small interfering RNA (siRNA) inhibition of EMMPRIN expression accelerated cell differentiation, exogenously added recombinant EMMPRIN inhibited differentiation by an MMP-mediated mechanism, as the MMP inhibitor marimastat abrogated EMMPRIN's effect. Our results further suggest that EMMPRIN regulates differentiation through an MMP activation of transforming growth factor beta (TGFβ), a known inhibitor of myoblast's differentiation, as the increased activation and signaling of TGFβ by EMMPRIN was attenuated in the presence of marimastat. EMMPRIN inhibition may thus represent a novel strategy in the treatment of muscular degenerative disorders.

  19. Urine matrix metalloproteinases and their extracellular inducer EMMPRIN in children with chronic kidney disease.

    Science.gov (United States)

    Musiał, Kinga; Bargenda, Agnieszka; Zwolińska, Danuta

    2015-07-01

    Transforming growth factor (TGF)beta1 and matrix metalloproteinases (MMPs) play an essential role in CKD-related tissue remodeling. However, there are no data on urine MMPs and their extracellular inducer EMMPRIN in CKD patients. The aim of study was to assess the concentrations of MMP-2, MMP-7, MMP-9, EMMPRIN and TGFbeta1 in serum and urine of CKD children and to analyze the potential relations between those parameters. Forty-one pre-dialysis CKD children and 23 age-matched controls were enrolled in the study. The concentrations of analyzed parameters were assessed by ELISA. Serum and urine values of MMP-2, MMP-7, MMP-9, EMMPRIN and TGFbeta1 were significantly elevated in CKD patients versus controls. The MMP-2 and MMP-9 levels in urine correlated significantly with the corresponding values in serum, whereas MMP-7, EMMPRIN and TGFbeta1 urine concentrations did not. There were also significant correlations between urine values of all parameters. The increased urine levels of MMPs, EMMPRIN and TGFbeta1 indicate enhanced proteolysis and renal tissue remodeling. In the case of MMP-7, EMMPRIN and TGFbeta1 those disturbances seem independent of enhanced serum activity of the corresponding enzymes. The urine MMP-7 and EMMPRIN concentrations may serve as new independent indices of tissue remodeling and renal interstitial fibrosis in children with CKD.

  20. Osteochondral lesions of the ankle joint in professional soccer players: treatment with autologous matrix-induced chondrogenesis.

    Science.gov (United States)

    Valderrabano, Victor; Barg, Alexej; Alattar, Abdulhameed; Wiewiorski, Martin

    2014-12-01

    Acute and recurrent ankle sprains and other trauma to the ankle joint are common injuries in soccer and can be accompanied by or result in osteochondral lesions of the ankle joint, majorly of the talus. Conservative treatment frequently fails. Several operative treatment techniques exist; however, the choice of the right procedure is difficult due to lack of literature with a high level of evidence. We present our treatment method for acute and chronic ankle osteochondral lesions with cystic formation approached by a new surgical technique combining bone plasty and a collagen matrix (autologous matrix-induced chondrogenesis). Therapeutic, Level IV: Case series. © 2014 The Author(s).

  1. Bee venom induces apoptosis and suppresses matrix metaloprotease-2 expression in human glioblastoma cells

    Directory of Open Access Journals (Sweden)

    Mohsen Sisakht

    Full Text Available Abstract Glioblastoma is the most common malignant brain tumor representing with poor prognosis, therapy resistance and high metastasis rate. Increased expression and activity of matrix metalloproteinase-2, a member of matrix metalloproteinase family proteins, has been reported in many cancers including glioblastoma. Inhibition of matrix metalloproteinase-2 expression has resulted in reduced aggression of glioblastoma tumors in several reports. In the present study, we evaluated effect of bee venom on expression and activity of matrix metalloproteinase-2 as well as potential toxicity and apoptogenic properties of bee venom on glioblastoma cells. Human A172 glioblastoma cells were treated with increasing concentrations of bee venom. Then, cell viability, apoptosis, matrix metalloproteinase-2 expression, and matrix metalloproteinase-2 activity were measured using MMT assay, propidium iodide staining, real time-PCR, and zymography, respectively. The IC50 value of bee venom was 28.5 µg/ml in which it leads to decrease of cell viability and induction of apoptosis. Incubation with bee venom also decreased the expression of matrix metalloproteinase-2 in this cell line (p < 0.05. In zymography, there was a reverse correlation between bee venom concentration and total matrix metalloproteinase-2 activity. Induction of apoptosis as well as inhibition of matrix metalloproteinase-2 activity and expression can be suggested as molecular mechanisms involved in cytotoxic and antimetastatic effects of bee venom against glioblastoma cells.

  2. Autologous Matrix-Induced Chondrogenesis: A Systematic Review of the Clinical Evidence.

    Science.gov (United States)

    Gao, Liang; Orth, Patrick; Cucchiarini, Magali; Madry, Henning

    2017-11-01

    The addition of a type I/III collagen membrane in cartilage defects treated with microfracture has been advocated for cartilage repair, termed "autologous matrix-induced chondrogenesis" (AMIC). To examine the current clinical evidence regarding AMIC for focal chondral defects. Systematic review. A systematic review was performed by searching PubMed, ScienceDirect, and Cochrane Library databases. Inclusion criteria were clinical studies of AMIC for articular cartilage repair, written in English. Relative data were extracted and critically analyzed. PRISMA guidelines were applied, the methodological quality of the included studies was assessed by the modified Coleman Methodology Score (CMS), and aggregate data were generated. Twenty-eight clinical articles were included: 12 studies (245 patients) of knee cartilage defects, 12 studies (214 patients) of ankle cartilage defects, and 4 studies (308 patients) of hip cartilage defects. The CMS demonstrated a suboptimal study design in the majority of published studies (knee, 57.8; ankle, 55.3; hip, 57.7). For the knee, 1 study reported significant clinical improvements for AMIC compared with microfracture for medium-sized cartilage defects (mean defect size 3.6 cm 2 ) after 5 years (level of evidence, 1). No study compared AMIC with matrix-assisted autologous chondrocyte implantation (ACI) in the knee. For the ankle, no clinical trial was available comparing AMIC versus microfracture or ACI. In the hip, only one analysis (level of evidence, 3) compared AMIC with microfracture for acetabular lesions. For medium-sized acetabular defects, one study (level of evidence, 3) found no significant differences between AMIC and ACI at 5 years. Specific aspects not appropriately discussed in the currently available literature include patient-related factors, membrane fixation, and defect properties. No treatment-related adverse events were reported. This systematic review reveals a paucity of high-quality, randomized controlled

  3. Effect of vitamin B12 on cleft palate induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin and dexamethasone in mice.

    Science.gov (United States)

    Zhao, Shu-Fan; Chai, Mao-Zhou; Wu, Min; He, Yong-Hong; Meng, Tian; Shi, Bing

    2014-03-01

    The purpose of this study was to investigate the effect of vitamin B12 on palatal development by co-administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and dexamethasone (DEX). We examined the morphological and histological features of the palatal shelf and expression levels of key signaling molecules (transforming growth factor-β3 (TGF-β3) and TGF-β type I receptor (activin receptor-like kinase 5, ALK5)) during palatogenesis among a control group (Group A), TCDD+DEX exposed group (Group B), and TCDD+DEX+vitamin B12 exposed group (Group C). While we failed to find that vitamin B12 decreased the incidence of cleft palate induced by TCDD+DEX treatment, the expression levels of key signaling molecules (TGF-β3 and ALK5) during palatogenesis were significantly modulated. In TCDD+DEX exposed and TCDD+DEX+vitamin B12 exposed groups, palatal shelves could not contact in the midline due to their small sizes. Our results suggest that vitamin B12 may inhibit the expression of some cleft palate inducers such as TGF-β3 and ALK5 in DEX+TCDD exposed mice, which may be beneficial against palatogenesis to some degree, even though we were unable to observe a protective role of vitamin B12 in morphological and histological alterations of palatal shelves induced by DEX and TCDD.

  4. Effect of vitamin B12 on cleft palate induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin and dexamethasone in mice*

    Science.gov (United States)

    Zhao, Shu-fan; Chai, Mao-zhou; Wu, Min; He, Yong-hong; Meng, Tian; Shi, Bing

    2014-01-01

    The purpose of this study was to investigate the effect of vitamin B12 on palatal development by co-administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and dexamethasone (DEX). We examined the morphological and histological features of the palatal shelf and expression levels of key signaling molecules (transforming growth factor-β3 (TGF-β3) and TGF-β type I receptor (activin receptor-like kinase 5, ALK5)) during palatogenesis among a control group (Group A), TCDD+DEX exposed group (Group B), and TCDD+DEX+vitamin B12 exposed group (Group C). While we failed to find that vitamin B12 decreased the incidence of cleft palate induced by TCDD+DEX treatment, the expression levels of key signaling molecules (TGF-β3 and ALK5) during palatogenesis were significantly modulated. In TCDD+DEX exposed and TCDD+DEX+vitamin B12 exposed groups, palatal shelves could not contact in the midline due to their small sizes. Our results suggest that vitamin B12 may inhibit the expression of some cleft palate inducers such as TGF-β3 and ALK5 in DEX+TCDD exposed mice, which may be beneficial against palatogenesis to some degree, even though we were unable to observe a protective role of vitamin B12 in morphological and histological alterations of palatal shelves induced by DEX and TCDD. PMID:24599693

  5. Expression and activity of matrix metalloproteinases in the uterus of bitches after spontaneous and induced abortion.

    Science.gov (United States)

    Kanca, H; Walter, I; Miller, I; Schäfer-Somi, S; Izgur, H; Aslan, S

    2011-04-01

    Aim of this study was to determine the intrauterine activity of matrix metalloproteinases (MMP)-2 and -9 after cessation of the local effect of progesterone. For this purpose, pregnancy was terminated in 10 bitches at mid-gestation with the progesterone receptor antagonist aglepristone (10 mg/kg body weight, sc, Alizine®; Virbac, France) at two subsequent days (group IRA = induced resorption/abortion). The IRA group was divided into two subgroups (Group I, n = 5, days 25-35 of pregnancy; group II, n = 5, days 36-45). Five further bitches were introduced with beginning abortion (group SRA = spontaneous resorption/abortion). Seven healthy bitches between day 25 and 45 of gestation served as controls. After ovariohysterectomy at the end of abortion and between days 25 and 45 of gestation, respectively, the distribution and activity of collagenases were investigated by immunohistochemistry and gelatin zymography. At placental sites, MMP-2 activity in the endometrium was significantly lower in IRA groups than in the SRA group (33.7 ± 11.8% and 39.3 ± 5.4% vs 52.2 ± 10.2%, p < 0.05); however, MMP-2 expression was lowest in the control group (control: 21.4 ± 6.3%; p < 0.01) and similarly in the myometrium (controls: 13.1 ± 2.5%; p < 0.05). MMP-9 activity was also lower in the endometrium and myometrium of the control group in comparison to SRA and IRA groups (11.8 ± 3.2%; p < 0.01 and 28.4 ± 32.8%; p < 0.05). At interplacental sites, the amount of active collagenases in the myometrium was significantly lower in the control group. It is concluded that the blockade of the biological progesterone effect was associated with an increase in activity of both collagenases. © 2010 Blackwell Verlag GmbH.

  6. Theoretical investigation on the inclusion of TCDD with β-cyclodextrin by performing QM calculations and MD simulations

    International Nuclear Information System (INIS)

    Pan, Wenxiao; Zhang, Dongju; Zhan, Jinhua

    2011-01-01

    Highlights: → We study the inclusion mechanism of TCDD with β-CD by theoretical methods. → Clearly, the formation of inclusion complex is an energetically driven process. → The inclusion complex can be detected by IR and Raman techniques. → The results imply that β-CD may be used as a host molecule to enrich TCDD molecules. - Abstract: The rapid enrichment and detection of trace polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are currently challenging issues in the field of environmental science. In this paper, by performing quantum chemistry (QM) calculations and molecular dynamics (MD) simulations, we studied the inclusion complexation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a representative PCDD molecule, with β-cyclodextrin (β-CD), one of the widely used compounds in supramolecular chemistry. The calculated results reveal that the stable inclusion complex can be formed in both the gas phase and solvent, which proposes that β-CD may serve as a potential substrate enriching TCDD. The calculated vibrational spectra indicate that the infrared (IR) and Raman spectroscopy may be suitable for the detection of β-CD-modified TCDD. The present theoretical results may be informative to environmental scientists who are devoting themselves to developing effective methods for detection and treatment of POPs.

  7. Assessment of chronic spontaneous urticaria by serum-induced tumor necrosis factor alpha and matrix metalloproteinase-9 release

    DEFF Research Database (Denmark)

    Falkencrone, Sidsel; Bindslev-Jensen, Carsten; Skov, Per Stahl

    BACKGROUND Previous studies from our group have demonstrated that IgE-mediated basophil activation leads to release of TNFα that in turn can induce matrix metallo-proteinase-9 (MMP-9) release from monocytes. We wished to investigate if serum from chronic spontaneous urticaria-patients with auto-a....... Release levels appeared to be positive correlated to ASST reaction in ASST+ patients but not to disease severity for CSU patients in general....

  8. Matrix metalloproteinase 7 restrains Helicobacter pylori-induced gastric inflammation and premalignant lesions in the stomach by altering macrophage polarization

    OpenAIRE

    Krakowiak, MS; Noto, JM; Piazuelo, MB; Hardbower, DM; Romero-Gallo, J; Delgado, A; Chaturvedi, R; Correa, P; Wilson, KT; Peek, RM

    2014-01-01

    Helicobacter pylori is the strongest risk factor for the development of gastric cancer. Although the specific mechanisms by which this pathogen induces carcinogenesis have not been fully elucidated, high-expression interleukin (IL)-1β alleles are associated with increased gastric cancer risk among H. pylori-infected persons. In addition, loss of matrix metalloproteinase 7 (MMP7) increases mucosal inflammation in mouse models of epithelial injury, and we have shown that gastric inflammation is...

  9. Matrix changes and side effects induced by electrokinetic treatment of porous and particulate materials

    DEFF Research Database (Denmark)

    Skibsted, Gry

    Transport of ions in an applied electric field holds many applications within both civil and environmental engineering, e.g. for removal of chlorides from concrete to hinder reinforcement corrosion, remediation of heavy metals from soils and other waste materials and recently for desalination...... electrodialytic remediation and the impact on the implementation of soil remediation, e.g. concerning the toxicity of residualsoluble Al in the soil matrix.Electrokinetic treatment was carried out as electrodialytic remediation (EDR) of three particulate matrices (soils and clay) and electrochemical desalination......H, chemical and porosity changes of the matrix during ED. In EDR it is not crucial to avoid matrix changes as in ED, but it is important to know which matrix changes are taking place, as these may influence the overall remediation result. In addition, the overall toxicity of the soil must not increase during...

  10. Increased expression of matrix metalloproteinases in the murine zymosan-induced multiple organ dysfunction syndrome.

    NARCIS (Netherlands)

    Volman, T.J.H.; Goris, R.J.A.; Lomme, R.M.L.M.; Groot, J. de; Verhofstad, A.A.J.; Hendriks, T.

    2004-01-01

    Matrix metalloproteinases (MMPs) have been implicated as mediators of tissue damage in several inflammatory diseases. Since the multiple organ dysfunction syndrome (MODS) is thought to result from systemic inflammation, overactivation of MMPs could contribute to the organ damage observed. The

  11. The Methoxyflavonoid Isosakuranetin Suppresses UV-B-Induced Matrix Metalloproteinase-1 Expression and Collagen Degradation Relevant for Skin Photoaging

    Directory of Open Access Journals (Sweden)

    Hana Jung

    2016-09-01

    Full Text Available Solar ultraviolet (UV radiation is a main extrinsic factor for skin aging. Chronic exposure of the skin to UV radiation causes the induction of matrix metalloproteinases (MMPs, such as MMP-1, and consequently results in alterations of the extracellular matrix (ECM and skin photoaging. Flavonoids are considered as potent anti-photoaging agents due to their UV-absorbing and antioxidant properties and inhibitory activity against UV-mediated MMP induction. To identify anti-photoaging agents, in the present study we examined the preventative effect of methoxyflavonoids, such as sakuranetin, isosakuranetin, homoeriodictyol, genkwanin, chrysoeriol and syringetin, on UV-B-induced skin photo-damage. Of the examined methoxyflavonoids, pretreatment with isosakuranetin strongly suppressed the UV-B-mediated induction of MMP-1 in human keratinocytes in a concentration-dependent manner. Isosakuranetin inhibited UV-B-induced phosphorylation of mitogen-activated protein kinase (MAPK signaling components, ERK1/2, JNK1/2 and p38 proteins. This result suggests that the ERK1/2 kinase pathways likely contribute to the inhibitory effects of isosakuranetin on UV-induced MMP-1 production in human keratinocytes. Isosakuranetin also prevented UV-B-induced degradation of type-1 collagen in human dermal fibroblast cells. Taken together, our findings suggest that isosakuranetin has the potential for development as a protective agent for skin photoaging through the inhibition of UV-induced MMP-1 production and collagen degradation.

  12. Proteomic Analysis of the Rat Ovary Following Chronic Low-Dose Exposure to 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD)

    NARCIS (Netherlands)

    Chen, Xi; Ma, Xiao-ming; Ma, Shi-wei; Coenraads, Pieter-Jan; Zhang, Chun-mei; Liu, Jing; Zhao, Li-jun; Sun, Min; Tang, Nai-jun

    2009-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a ubiquitously distributed endocrine-disrupting chemical and reproductive toxicant. In order to elucidate low-dose TCDD-mediated effects on reproductive or endocrine functions, female Sprague-Dawley rats were orally administered various concentrations

  13. Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on signal transduction pathway-related protein expression in liver and cerebrum of rhesus monkey

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Mari; Akema, Satoshi; Tsuzuki, Masami; Kubota, Shunichiro [Tokyo Univ. (Japan); Korenaga, Tatsumi; Fukusato, Toshio [Teikyo Univ. of School of Medicine, Tokyo (Japan); Asaoka, Kazuo [Kyoto Univ. (Japan); Murata, Nobuo [Teikyo Univ. of School of Medicine, Kawasaki (Japan); Nomizu, Motoyoshi [Hokkaido Univ., Sapporo (Japan); Arima, Akihiro [Shin Nippon Biomedical Laboratories, Ltd., Kagoshima (Japan)

    2004-09-15

    2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to produce a wide range of toxic and biochemical effects in experimental animals, including immunological dysfunctions, chloracne, tetragenecity and carcinogenesis. Recently, the potential impact of dioxins on neurological disorders with particular focus on attention deficit hyperactivity disorder (ADHD) are concerned. Although a lot of information is available from studies in rodents, not much is known of the low dose effects of TCDD in non-human primates. In higher animals, dioxins are metabolized slowly, as evidenced by the estimated TCDD half-life of 5.8 to 14.1 years. Therefore, it is necessary to investigate the long-term effects of TCDD on human health. Considering the pronounced species differences observed in some studies of TCDD, the studies using primates are needed for assessment of TCDD exposure on human health. We have been studying the metabolism and the effects of single administration of TCDD on pregnant monkey (F0) and F1 rhesus monkey. The focus of the present study is to study the effects of TCDD on signal transduction pathway-related protein levels in various organs, especially in liver and brain of F0 monkeys.

  14. A single administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin that produces reduced food and water intake induces long-lasting expression of corticotropin-releasing factor, arginine vasopressin, and proopiomelanocortin in rat brain

    International Nuclear Information System (INIS)

    Moon, Bo-Hyun; Hong, Chang Gwun; Kim, Soo-Young; Kim, Hyun-Ju; Shin, Seung Keon; Kang, Seungwoo; Lee, Kuem-Ju; Kim, Yong-Ku; Lee, Min-Soo; Shin, Kyung-Ho

    2008-01-01

    The mechanism by which a single administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) reduces food and water intake is unclear. We examined whether such a food and water intake-reducing single administration of TCDD induced changes in corticotropin-releasing factor (CRF), arginine vasopressin (AVP), and proopiomelanocortin (POMC) expression in rat brain. To observe time-dependent changes in these neuropeptides, male Sprague-Dawley rats were given TCDD (50 μg/kg) and terminated 1, 2, 4, or 7 days later. In addition, to observe dose-dependent changes in feeding and neuropeptides, rats were also given a range of TCDD doses (12.5, 25, or 50 μg/kg) and terminated 14 days later. TCDD suppressed food and water intake over 14 days in a dose-dependent manner. TCDD treatment also increased CRF and POMC mRNA levels in the hypothalamic paraventricular nucleus (PVN) and arcuate nucleus, respectively, in a dose- and time-dependent manner. These increases were related to decreased food intake following TCDD administration. TCDD treatment increased AVP and CRF mRNA levels in the PVN, and these increases were related to decreased water intake. Interestingly, the increases in CRF, AVP and POMC expression were observed 7 to 14 days after TCDD administration. These results suggest that a single administration of TCDD induced long-lasting increases in CRF, AVP, and POMC mRNA levels in the hypothalamus and that these changes are related to reduced food and water intake 7 to 14 days after TCDD administration

  15. Residual Stress Induced Mechanical Property Enhancement in Steel Encapsulated Light Metal Matrix Composites

    Science.gov (United States)

    Fudger, Sean James

    Macro hybridized systems consisting of steel encapsulated light metal matrix composites (MMCs) were produced with the goal of creating a low cost/light weight composite system with enhanced mechanical properties. MMCs are frequently incorporated into advanced material systems due to their tailorable material properties. However, they often have insufficient ductility for many structural applications. The macro hybridized systems take advantage of the high strength, modulus, and damage tolerance of steels and high specific stiffness and low density of MMCs while mitigating the high density of steels and the poor ductility of MMCs. Furthermore, a coefficient of thermal expansion (CTE) mismatch induced residual compressive stress method is utilized as a means of improving the ductility of the MMCs and overall efficiency of the macro hybridized systems. Systems consisting of an A36, 304 stainless steel, or NitronicRTM 50 stainless steel shell filled with an Al-SiC, Al-Al2O3, or Mg-B4C MMC are evaluated in this work. Upon cooling from processing temperatures, residual strains are generated due to a CTE mismatch between each of the phases. The resulting systems offer higher specific properties and a more structurally efficient system can be attained. Mechanical testing was performed and improvements in yield stress, ultimate tensile stress, and ductility were observed. However, the combination of these dissimilar materials often results in the formation of intermetallic compounds. In certain loading situations, these typically brittle intermetallic layers can result in degraded performance. X-ray Diffraction (XRD), X-ray Energy Dispersive Spectroscopy (EDS), and Electron Backscatter Diffraction (EBSD) are utilized to characterize the intermetallic layer formation at the interface between the steel and MMC. As the residual stress condition in each phase has a large impact on the mechanical property improvement, accurate quantification of these strains/stresses is

  16. Expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and its related extracellular matrix degrading enzymes in the endometrium during estrous cycle and early gestation in cattle.

    Science.gov (United States)

    Mishra, Birendra; Kizaki, Keiichiro; Koshi, Katsuo; Ushizawa, Koichi; Takahashi, Toru; Hosoe, Misa; Sato, Takashi; Ito, Akira; Hashizume, Kazuyoshi

    2010-06-11

    Extracellular matrix metalloproteinase inducer (EMMPRIN) regulates several biological functions involving the modulation of cell behaviors via cell-cell and cell-matrix interactions. According to its diverse functions, we hypothesized that EMMPRIN may play an important role in endometrial remodeling and establishment of pregnancy in cow. In this study, endometrial tissues from the cyclic cows during before ovulation, after ovulation and middle of estrous cycle; and pregnant endometrial tissues from Day 19 to 35 of gestation have been used. Expression of mRNA was analyzed by RT-PCR, qPCR and in situ hybridization whereas protein expression by immunohistochemistry and western blot analysis. EMMPRIN mRNA was expressed in both cyclic and pregnant endometrium and significantly higher in the endometrium at Day 35 of gestation than the cyclic endometrium. In Western blot analysis, an approximately 65 kDa band was detected in the endometrium, and approximately 51 kDa in the cultured bovine epithelial cells and BT-1 cells, respectively. Both in situ hybridization and immunohistochemistry data showed that EMMPRIN was primarily expressed in luminal and glandular epithelium with strong staining on Day 19 conceptus. At Day 19 of gestation, expression of EMMPRIN mRNA on luminal epithelium was decreased than that observed at middle of estrous cycle, however, on Day 30 of gestation, slightly increased expression was found at the site of placentation. Expression of matrix metalloproteinase-2 (MMP-2) and MMP-14 mRNA were mainly detected in stroma and their expression also decreased at Day 19 of gestation however it was also expressed at the site of placentation at Day 30 of gestation as observed for EMMPRIN. Expression of MMP-1 or -9 mRNA was very low and was below the detection limit in the cyclic and pregnant endometrium. EMMPRIN from the luminal epithelium may regulate the expression of stromal MMP-2 and -14 suggesting its crucial role in adhesion and fusion of embryo to luminal

  17. Expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and its related extracellular matrix degrading enzymes in the endometrium during estrous cycle and early gestation in cattle

    Science.gov (United States)

    2010-01-01

    Background Extracellular matrix metalloproteinase inducer (EMMPRIN) regulates several biological functions involving the modulation of cell behaviors via cell-cell and cell-matrix interactions. According to its diverse functions, we hypothesized that EMMPRIN may play an important role in endometrial remodeling and establishment of pregnancy in cow. Methods In this study, endometrial tissues from the cyclic cows during before ovulation, after ovulation and middle of estrous cycle; and pregnant endometrial tissues from Day 19 to 35 of gestation have been used. Expression of mRNA was analyzed by RT-PCR, qPCR and in situ hybridization whereas protein expression by immunohistochemistry and western blot analysis. Results EMMPRIN mRNA was expressed in both cyclic and pregnant endometrium and significantly higher in the endometrium at Day 35 of gestation than the cyclic endometrium. In Western blot analysis, an approximately 65 kDa band was detected in the endometrium, and approximately 51 kDa in the cultured bovine epithelial cells and BT-1 cells, respectively. Both in situ hybridization and immunohistochemistry data showed that EMMPRIN was primarily expressed in luminal and glandular epithelium with strong staining on Day 19 conceptus. At Day 19 of gestation, expression of EMMPRIN mRNA on luminal epithelium was decreased than that observed at middle of estrous cycle, however, on Day 30 of gestation, slightly increased expression was found at the site of placentation. Expression of matrix metalloproteinase-2 (MMP-2) and MMP-14 mRNA were mainly detected in stroma and their expression also decreased at Day 19 of gestation however it was also expressed at the site of placentation at Day 30 of gestation as observed for EMMPRIN. Expression of MMP-1 or -9 mRNA was very low and was below the detection limit in the cyclic and pregnant endometrium. Conclusion EMMPRIN from the luminal epithelium may regulate the expression of stromal MMP-2 and -14 suggesting its crucial role in

  18. Expression of extracellular matrix metalloproteinase inducer (EMMPRIN and its related extracellular matrix degrading enzymes in the endometrium during estrous cycle and early gestation in cattle

    Directory of Open Access Journals (Sweden)

    Hosoe Misa

    2010-06-01

    Full Text Available Abstract Background Extracellular matrix metalloproteinase inducer (EMMPRIN regulates several biological functions involving the modulation of cell behaviors via cell-cell and cell-matrix interactions. According to its diverse functions, we hypothesized that EMMPRIN may play an important role in endometrial remodeling and establishment of pregnancy in cow. Methods In this study, endometrial tissues from the cyclic cows during before ovulation, after ovulation and middle of estrous cycle; and pregnant endometrial tissues from Day 19 to 35 of gestation have been used. Expression of mRNA was analyzed by RT-PCR, qPCR and in situ hybridization whereas protein expression by immunohistochemistry and western blot analysis. Results EMMPRIN mRNA was expressed in both cyclic and pregnant endometrium and significantly higher in the endometrium at Day 35 of gestation than the cyclic endometrium. In Western blot analysis, an approximately 65 kDa band was detected in the endometrium, and approximately 51 kDa in the cultured bovine epithelial cells and BT-1 cells, respectively. Both in situ hybridization and immunohistochemistry data showed that EMMPRIN was primarily expressed in luminal and glandular epithelium with strong staining on Day 19 conceptus. At Day 19 of gestation, expression of EMMPRIN mRNA on luminal epithelium was decreased than that observed at middle of estrous cycle, however, on Day 30 of gestation, slightly increased expression was found at the site of placentation. Expression of matrix metalloproteinase-2 (MMP-2 and MMP-14 mRNA were mainly detected in stroma and their expression also decreased at Day 19 of gestation however it was also expressed at the site of placentation at Day 30 of gestation as observed for EMMPRIN. Expression of MMP-1 or -9 mRNA was very low and was below the detection limit in the cyclic and pregnant endometrium. Conclusion EMMPRIN from the luminal epithelium may regulate the expression of stromal MMP-2 and -14

  19. Chinese yellow wine inhibits production of homocysteine-induced extracellular matrix metalloproteinase-2 in cultured rat vascular smooth muscle cells.

    Science.gov (United States)

    Guo, Hangyuan; Wang, Ping; You, Binquan; Xing, Yangbo; Lee, Jong-Dae

    2007-06-01

    Regular consumption of moderate amounts of Chinese yellow wine is associated with a reduced risk of coronary disease. Matrix metalloproteinases (MMPs) that participate in extracellular matrix degradation have been involved in atherosclerotic plaque growth and instability. The present research aimed to study the effects of Chinese yellow wine on the production of homocysteine (Hcy)-induced extracellular MMP-2 in cultured rats vascular smooth muscle cells (VSMCs). We examined the effects of different Hcy levels (0-1000 micromol/l) on MMP-2 production, and the effects of Chinese yellow wine with low alcohol concentrations (12-19%) on Hcy-induced MMP-2 in cultured rat (VSMCs) using gelatin zymography and western blotting. We further compared the changes of MMP-2 under various treatments for 12, 24 and 48 h. Hcy (50-1000 micromol/l) increased the production of MMP-2 significantly in a dose-dependent manner. Increased production of MMP-2 induced by Hcy was reduced by extracellularly added Chinese yellow wine. Production of MMP-2 under various treatments for 48 h increased more than 12 and 24 h. Extracellularly added Chinese yellow wine decreased Hcy-induced MMP-2 secretion. The inhibitory effect of yellow wine on the activation of MMP-2 might contribute to their beneficial effects on the cardiovascular system.

  20. Multiphoton microscopy of engineered dermal substitutes: assessment of 3-D collagen matrix remodeling induced by fibroblast contraction

    Science.gov (United States)

    Pena, Ana-Maria; Fagot, Dominique; Olive, Christian; Michelet, Jean-François; Galey, Jean-Baptiste; Leroy, Frédéric; Beaurepaire, Emmanuel; Martin, Jean-Louis; Colonna, Anne; Schanne-Klein, Marie-Claire

    2010-09-01

    Dermal fibroblasts are responsible for the generation of mechanical forces within their surrounding extracellular matrix and can be potentially targeted by anti-aging ingredients. Investigation of the modulation of fibroblast contraction by these ingredients requires the implementation of three-dimensional in situ imaging methodologies. We use multiphoton microscopy to visualize unstained engineered dermal tissue by combining second-harmonic generation that reveals specifically fibrillar collagen and two-photon excited fluorescence from endogenous cellular chromophores. We study the fibroblast-induced reorganization of the collagen matrix and quantitatively evaluate the effect of Y-27632, a RhoA-kinase inhibitor, on dermal substitute contraction. We observe that collagen fibrils rearrange around fibroblasts with increasing density in control samples, whereas collagen fibrils show no remodeling in the samples containing the RhoA-kinase inhibitor. Moreover, we show that the inhibitory effects are reversible. Our study demonstrates the relevance of multiphoton microscopy to visualize three-dimensional remodeling of the extracellular matrix induced by fibroblast contraction or other processes.

  1. Laser-induced ion emission during polymer deposition from a flash-frozen water ice matrix

    DEFF Research Database (Denmark)

    Rodrigo, K.; Toftmann, Bo; Schou, Jørgen

    2004-01-01

    Flash-frozen water solutions of 1% weight PEG (polyethylene glycol) at -50 degreesC were used as targets at a laser wavelength of 355 nm for polymer deposition with Matrix-Assisted Pulsed Laser Evaporation (MAPLE). For medium laser fluences the transfer of PEG material to the substrate...... was accompanied by a pronounced ion flow from the matrix target which increases with fluence F as F-12. At the highest fluence the ion flow was partly attenuated, presumably due to plume shielding. Below a threshold of 3.5 J/cm(2) the PEG was deposited without any measurable ion emission from the target. (C) 2004...

  2. Near-infrared laser-induced structural changes of glycine·water complexes in an Ar matrix.

    Science.gov (United States)

    Kócs, Lenke; Najbauer, Eszter E; Bazsó, Gábor; Magyarfalvi, Gábor; Tarczay, György

    2015-03-19

    The structures of glycine·H2O complexes have been reinvestigated in low-temperature inert matrices. To go beyond the former matrix-isolation IR studies, NIR laser irradiation was used to change the relative abundances of the different complexes in the matrix. It is shown that the irradiation of the first overtone of the OH stretching mode of glycine as well as of the first overtone of the OH stretching mode of the water molecule in the complex can induce structural changes. Comparison of the experimental IR spectra with the IR spectra computed for different structures resulted in more reliable assignments of spectral patterns and identification of more structures than in former studies.

  3. Thermomechanically induced residual strains in Al/SiCp metal-matrix composites

    DEFF Research Database (Denmark)

    Lorentzen, T.; Clarke, A.P.

    1998-01-01

    Residual lattice strains in the aluminium and SiC phases of F3S.20S extruded A359 20% SiC metal-matrix composite were measured by using neutron diffi action at room and elevated temperatures to monitor the effects of in situ uniaxial plastic deformations. The results are interpreted with referenc...

  4. Phenotypic switching induced by damaged matrix is associated with DNA methyltransferase 3A (DNMT3A activity and nuclear localization in smooth muscle cells (SMC.

    Directory of Open Access Journals (Sweden)

    Jia-Xin Jiang

    Full Text Available Extracellular matrix changes are often crucial inciting events for fibroproliferative disease. Epigenetic changes, specifically DNA methylation, are critical factors underlying differentiated phenotypes. We examined the dependency of matrix-induced fibroproliferation and SMC phenotype on DNA methyltransferases. The cooperativity of matrix with growth factors, cell density and hypoxia was also examined. Primary rat visceral SMC of early passage (0-2 were plated on native collagen or damaged/heat-denatured collagen. Hypoxia was induced with 3% O2 (balanced 5% CO2 and 95% N2 over 48 hours. Inhibitors were applied 2-3 hours after cells were plated on matrix, or immediately before hypoxia. Cells were fixed and stained for DNMT3A and smooth muscle actin (SMA or smooth muscle myosin heavy chain. Illumina 450 K array of CpG sites was performed on bisulfite-converted DNA from smooth muscle cells on damaged matrix vs native collagen. Matrix exquisitely regulates DNMT3A localization and expression, and influences differentiation in SMCs exposed to denatured matrix +/- hypoxia. Analysis of DNA methylation signatures showed that Matrix caused significant DNA methylation alterations in a discrete number of CpG sites proximal to genes related to SMC differentiation. Matrix has a profound effect on the regulation of SMC phenotype, which is associated with altered expression, localization of DNMTs and discrete changes DNA methylation.

  5. Corrosion-induced changes in pore-size distributions of fuel-matrix material

    International Nuclear Information System (INIS)

    Krautwasser, P.; Eatherly, W.P.

    1981-01-01

    In order to understand the mechanism of metallic fission-product adsorption and desorption as well as diffusion in graphitic materials, a detailed knowledge of the material microstructure is essential. Different types of grahitic matrix material used or to be used in fuel elements of the German HTR Program were measured at ORNL in cooperation with the Hahn-Meitner-Institut Berlin. Actual measurements of fission product diffusion and adsorption/desorption were performed at HMI Berlin

  6. A two-channel R-matrix analysis of magnetic field induced Feshbach resonances

    DEFF Research Database (Denmark)

    Nygaard, Nicolai; Schneider, B. I.; Julienne, P. S.

    2006-01-01

    such an effective Feshbach model can be constructed from knowledge of a few key parameters, characterizing the atomic Born-Oppenheimer potentials and the low energy scattering near the resonance. These parameters may be obtained either from experiment or full coupled channels calculations. Using R-matrix theory we...... analyze the bound state spectrum and the scattering properties of the two-channel model, and find it to be in good agreement with exact calculations....

  7. Laser Induced Fluorescence (LIF) Nondestructive Evaluation of Incipient Heat Damage in Polymer Matrix Composites, A2476

    Science.gov (United States)

    2017-02-15

    default/files/datasheets/CYCOM_5250-4_032012. pdf . CYCOM 977-3 Tech Data Sheet. Technical Data Sheet for CYCOM® 977-3 Epoxy Resin System, Cytec... resin due to the addition of a thermoplastic toughened phase to the epoxy that forms the matrix (CYCOM® 977-3 Technical Data Sheet), the LIF response is...Technology Application, NASA Contractor Report 178272. Luoma & Rowland, 1986. G. A. Luoma & R. D. Rowland, “Environmental Degradation of an Epoxy Resin

  8. Growth-induced axial buckling of a slender elastic filament embedded in an isotropic elastic matrix

    KAUST Repository

    O'Keeffe, Stephen G.

    2013-11-01

    We investigate the problem of an axially loaded, isotropic, slender cylinder embedded in a soft, isotropic, outer elastic matrix. The cylinder undergoes uniform axial growth, whilst both the cylinder and the surrounding elastic matrix are confined between two rigid plates, so that this growth results in axial compression of the cylinder. We use two different modelling approaches to estimate the critical axial growth (that is, the amount of axial growth the cylinder is able to sustain before it buckles) and buckling wavelength of the cylinder. The first approach treats the filament and surrounding matrix as a single 3-dimensional elastic body undergoing large deformations, whilst the second approach treats the filament as a planar, elastic rod embedded in an infinite elastic foundation. By comparing the results of these two approaches, we obtain an estimate of the foundation modulus parameter, which characterises the strength of the foundation, in terms of the geometric and material properties of the system. © 2013 Elsevier Ltd. All rights reserved.

  9. Role of the Ah locus in suppression of cytotoxic T lymphocyte activity by halogenated aromatic hydrocarbons (PCBs and TCDD): Structure-activity relationships and effects in C57Bl/6 mice congenic at the Ah locus

    International Nuclear Information System (INIS)

    Kerkvliet, N.I.; Baecher-Steppan, L.; Smith, B.B.; Youngberg, J.A.; Henderson, M.C.; Buhler, D.R.

    1990-01-01

    Previous studies have shown that the generation of cytotoxic T lymphocytes (CTL) following allogeneic tumor challenge is suppressed in Ah-responsive C57Bl/6 mice treated with a single oral dose of the toxic, Ah receptor-binding 3,4,5,3',4',5'-hexachlorobiphenyl (HxCB). The present studies have examined the specific role of the Ah receptor in this immunotoxic response by utilizing HxCB isomers of known, varied affinity for the Ah receptor as well as by comparing effects of high-affinity Ah receptor ligands (3,4,5,3',4',5'-HxCB and 2,3,7,8-tetrachlorodibenzo-p-dioxin [TCDD]) on the CTL response of mice that differ only at the Ah locus, that is, Ah-responsive (Ahbb) and Ah-nonresponsive (Ahdd) congenic C57Bl/6 mice. Correlative changes in thymic weight, serum corticosterone (CS) levels, and spleen cellularity were also measured. The potency of HxCB congeners (3,4,5,3',4',5'-; 2,3,4,5,3',4'-; 2,4,5,2',4',5'-) and 2,3,7,8-TCDD to suppress the CTL response, to reduce spleen cellularity, to cause thymic atrophy, and to elevate serum CS levels was directly correlated with the binding affinity of the congener for the Ah receptor. Furthermore, these parameters of immunotoxicity in Ahdd C57Bl/6 mice were significantly more resistant to alterations induced by either 3,4,5,3',4',5'-HxCB or 2,3,7,8-TCDD as compared to Ahbb C57Bl/6 mice. These results strongly support an Ah receptor-dependent immunotoxic mechanism in suppression of the CTL response following acute exposure to halogenated aromatic hydrocarbons

  10. Cartilage oligomeric matrix protein deficiency promotes early onset and the chronic development of collagen-induced arthritis

    DEFF Research Database (Denmark)

    Geng, Hui; Carlsen, Stefan; Nandakumar, Kutty

    2008-01-01

    ABSTRACT: INTRODUCTION: Cartilage oligomeric matrix protein (COMP) is a homopentameric protein in cartilage. The development of arthritis, like collagen-induced arthritis (CIA), involves cartilage as a target tissue. We have investigated the development of CIA in COMP-deficient mice. METHODS: COMP......-deficient mice in the 129/Sv background were backcrossed for 10 generations against B10.Q mice, which are susceptible to chronic CIA. COMP-deficient and wild-type mice were tested for onset, incidence, and severity of arthritis in both the collagen and collagen antibody-induced arthritis models. Serum anti......-collagen II and anti-COMP antibodies as well as serum COMP levels in arthritic and wild-type mice were measured by enzyme-linked immunosorbent assay. RESULTS: COMP-deficient mice showed a significant early onset and increase in the severity of CIA in the chronic phase, whereas collagen II-antibody titers were...

  11. Exercise-induced regulation of matrix metalloproteinases in the skeletal muscle of subjects with type 2 diabetes

    DEFF Research Database (Denmark)

    Scheede-Bergdahl, Celena; Bergdahl, Andreas; Schjerling, Peter

    2014-01-01

    -training. At baseline, there were no effects of diabetes on MMP or TIMP mRNA or protein. mRNA and protein response to training was similar in both groups, except active MMP-2 protein was elevated post training in T2DM only. Our results indicate that exercise-induced stimulation of MMPs is preserved in skeletal muscle......Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMP) play a critical role during vascular remodelling, in both health and disease. Impaired MMP regulation is associated with many diabetes-related complications. This study examined whether exercise-induced regulation of MMPs...... is maintained in the skeletal muscle of patients with uncomplicated type 2 diabetes (T2DM). Subjects [12 T2DM, 9 healthy control subjects (CON)] underwent 8 weeks of physical training. Messenger RNA (mRNA) was measured at baseline, during and after 8 weeks of training. Protein was measured pre- and post...

  12. Dioxin induces genomic instability in mouse embryonic fibroblasts.

    Directory of Open Access Journals (Sweden)

    Merja Korkalainen

    Full Text Available Ionizing radiation and certain other exposures have been shown to induce genomic instability (GI, i.e., delayed genetic damage observed many cell generations later in the progeny of the exposed cells. The aim of this study was to investigate induction of GI by a nongenotoxic carcinogen, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD. Mouse embryonic fibroblasts (C3H10T1/2 were exposed to 1, 10 or 100 nM TCDD for 2 days. Micronuclei (MN and expression of selected cancer-related genes were assayed both immediately and at a delayed point in time (8 days. For comparison, similar experiments were done with cadmium, a known genotoxic agent. TCDD treatment induced an elevated frequency of MN at 8 days, but not directly after the exposure. TCDD-induced alterations in gene expression were also mostly delayed, with more changes observed at 8 days than at 2 days. Exposure to cadmium produced an opposite pattern of responses, with pronounced effects immediately after exposure but no increase in MN and few gene expression changes at 8 days. Although all responses to TCDD alone were delayed, menadione-induced DNA damage (measured by the Comet assay, was found to be increased directly after a 2-day TCDD exposure, indicating that the stability of the genome was compromised already at this time point. The results suggested a flat dose-response relationship consistent with dose-response data reported for radiation-induced GI. These findings indicate that TCDD, although not directly genotoxic, induces GI, which is associated with impaired DNA damage response.

  13. Glucocorticoids induce apoptosis and matrix metalloproteinase-13 expression in chondrocytes through the NOX4/ROS/p38 MAPK pathway.

    Science.gov (United States)

    Huang, Ying; Cai, Gui-Quan; Peng, Jian-Ping; Shen, Chao

    2018-03-08

    Based on the results from our previous study, dexamethasone (Dex) increases reactive oxygen species (ROS) levels and subsequently induces cell death and matrix catabolism in chondrocytes. Nevertheless, the mechanism underlying this phenomenon remains unclear. Nicotinamide adenine dinucleotide (phosphate) (NADPH) oxidase 4 (NOX4) is one of the major enzymes responsible for intracellular ROS production during the inflammatory process. The objective of the current study was to investigate the role of NOX4 in Dex-induced ROS over-production. Healthy chondrocytes were harvested from the cartilage debris from 6 female patients. NOX4 and p38 mitogen-activated protein kinase (MAPK) expression levels in these cells were evaluated in the presence of Dex. Changes in the number of apoptotic and viable Dex-treated chondrocytes were recorded after the cells were treated with NOX and p38 MAPK inhibitors. Changes in matrix metalloproteinase 13 (MMP-13) expression levels in Dex-treated chondrocytes were also investigated. The Dex treatment increased NOX4 expression via the glucocorticoid receptor (GR). Treatment of cells with apocynin, a NOX inhibitor, decreased intracellular ROS levels and inhibited p38 MAPK activation. Treatment of cells with a ROS scavenger also reduced p38 MAPK expression. Treatment of cells with a NOX inhibitor, ROS scavenger and p38 MAPK inhibitor rescued chondrocytes from Dex-induced apoptosis. Moreover, treatment of cells with these agents blocked MMP-13 expression in Dex-treated chondrocytes. NOX4 silencing also suppressed p38 MAPK and MMP-13 expression. Dex triggered apoptosis and MMP-13 expression through the NOX4/ROS/p38 MAPK signaling pathway. NOX4 may be a therapeutic target in the management of Dex-induced complications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Fibroblast-Derived Extracellular Matrix Induces Chondrogenic Differentiation in Human Adipose-Derived Mesenchymal Stromal/Stem Cells in Vitro

    Science.gov (United States)

    Dzobo, Kevin; Turnley, Taegyn; Wishart, Andrew; Rowe, Arielle; Kallmeyer, Karlien; van Vollenstee, Fiona A.; Thomford, Nicholas E.; Dandara, Collet; Chopera, Denis; Pepper, Michael S.; Parker, M. Iqbal

    2016-01-01

    Mesenchymal stromal/stem cells (MSCs) represent an area being intensively researched for tissue engineering and regenerative medicine applications. MSCs may provide the opportunity to treat diseases and injuries that currently have limited therapeutic options, as well as enhance present strategies for tissue repair. The cellular environment has a significant role in cellular development and differentiation through cell–matrix interactions. The aim of this study was to investigate the behavior of adipose-derived MSCs (ad-MSCs) in the context of a cell-derived matrix so as to model the in vivo physiological microenvironment. The fibroblast-derived extracellular matrix (fd-ECM) did not affect ad-MSC morphology, but reduced ad-MSC proliferation. Ad-MSCs cultured on fd-ECM displayed decreased expression of integrins α2 and β1 and subsequently lost their multipotency over time, as shown by the decrease in CD44, Octamer-binding transcription factor 4 (OCT4), SOX2, and NANOG gene expression. The fd-ECM induced chondrogenic differentiation in ad-MSCs compared to control ad-MSCs. Loss of function studies, through the use of siRNA and a mutant Notch1 construct, revealed that ECM-mediated ad-MSCs chondrogenesis requires Notch1 and β-catenin signaling. The fd-ECM also showed anti-senescence effects on ad-MSCs. The fd-ECM is a promising approach for inducing chondrogenesis in ad-MSCs and chondrogenic differentiated ad-MSCs could be used in stem cell therapy procedures. PMID:27527147

  15. Fibroblast-Derived Extracellular Matrix Induces Chondrogenic Differentiation in Human Adipose-Derived Mesenchymal Stromal/Stem Cells in Vitro

    Directory of Open Access Journals (Sweden)

    Kevin Dzobo

    2016-08-01

    Full Text Available Mesenchymal stromal/stem cells (MSCs represent an area being intensively researched for tissue engineering and regenerative medicine applications. MSCs may provide the opportunity to treat diseases and injuries that currently have limited therapeutic options, as well as enhance present strategies for tissue repair. The cellular environment has a significant role in cellular development and differentiation through cell–matrix interactions. The aim of this study was to investigate the behavior of adipose-derived MSCs (ad-MSCs in the context of a cell-derived matrix so as to model the in vivo physiological microenvironment. The fibroblast-derived extracellular matrix (fd-ECM did not affect ad-MSC morphology, but reduced ad-MSC proliferation. Ad-MSCs cultured on fd-ECM displayed decreased expression of integrins α2 and β1 and subsequently lost their multipotency over time, as shown by the decrease in CD44, Octamer-binding transcription factor 4 (OCT4, SOX2, and NANOG gene expression. The fd-ECM induced chondrogenic differentiation in ad-MSCs compared to control ad-MSCs. Loss of function studies, through the use of siRNA and a mutant Notch1 construct, revealed that ECM-mediated ad-MSCs chondrogenesis requires Notch1 and β-catenin signaling. The fd-ECM also showed anti-senescence effects on ad-MSCs. The fd-ECM is a promising approach for inducing chondrogenesis in ad-MSCs and chondrogenic differentiated ad-MSCs could be used in stem cell therapy procedures.

  16. Pregnancy-induced adaptations in intramuscular extracellular matrix of rat pelvic floor muscles.

    Science.gov (United States)

    Alperin, Marianna; Kaddis, Timothy; Pichika, Rajeswari; Esparza, Mary C; Lieber, Richard L

    2016-08-01

    Birth trauma to pelvic floor muscles is a major risk factor for pelvic floor disorders. Intramuscular extracellular matrix determines muscle stiffness, supports contractile component, and shields myofibers from mechanical strain. Our goal was to determine whether pregnancy alters extracellular matrix mechanical and biochemical properties in a rat model, which may provide insights into the pathogenesis of pelvic floor muscle birth injury. To examine whether pregnancy effects were unique to pelvic floor muscles, we also studied a hind limb muscle. Passive mechanical properties of coccygeus, iliocaudalis, pubocaudalis, and tibialis anterior were compared among 3-month old Sprague-Dawley virgin, late-pregnant, and postpartum rats. Muscle tangent stiffness was calculated as the slope of the stress-sarcomere length curve between 2.5 and 4.0 μm, obtained from a stress-relaxation protocol at a bundle level. Elastin and collagen isoform concentrations were quantified by the use of enzyme-linked immunosorbent assay. Enzymatic and glycosylated collagen crosslinks were determined by high-performance liquid chromatography. Data were compared by the use of repeated-measures, 2-way analysis of variance with Tukey post-hoc testing. Correlations between mechanical and biochemical parameters were assessed by linear regressions. Significance was set to P pelvic floor muscle stiffness did not differ from virgins (P > .3). A substantial increase in collagen V in coccygeus and pubocaudalis was observed in late-pregnant, compared with virgin, animals, (P pelvic floor muscles (P pelvic floor muscles, the tibialis anterior was unaltered by pregnancy. In contrast to other pelvic tissues, pelvic floor muscle stiffness increased in pregnancy, returning to prepregnancy state postpartum. This adaptation may shield myofibers from excessive mechanical strain during parturition. Biochemical alterations in pelvic floor muscle extracellular matrix due to pregnancy include increase in collagen V

  17. Pregnancy-induced adaptations in intramuscular extracellular matrix of rat pelvic floor muscles

    Science.gov (United States)

    Alperin, Marianna; Kaddis, Timothy; Pichika, Rajeswari; Esparza, Mary C.; Lieber, Richard L.

    2017-01-01

    BACKGROUND Birth trauma to pelvic floor muscles is a major risk factor for pelvic floor disorders. Intramuscular extracellular matrix determines muscle stiffness, supports contractile component, and shields myofibers from mechanical strain. OBJECTIVE Our goal was to determine whether pregnancy alters extracellular matrix mechanical and biochemical properties in a rat model, which may provide insights into the pathogenesis of pelvic floor muscle birth injury. To examine whether pregnancy effects were unique to pelvic floor muscles, we also studied a hind limb muscle. STUDY DESIGN Passive mechanical properties of coccygeus, iliocaudalis, pubocaudalis, and tibialis anterior were compared among 3-month old Sprague–Dawley virgin, late-pregnant, and postpartum rats. Muscle tangent stiffness was calculated as the slope of the stress–sarcomere length curve between 2.5 and 4.0 μm, obtained from a stress-relaxation protocol at a bundle level. Elastin and collagen isoform concentrations were quantified by the use of enzyme-linked immunosorbent assay. Enzymatic and glycosylated collagen crosslinks were determined by high-performance liquid chromatography. Data were compared by the use of repeated-measures, 2-way analysis of variance with Tukey post-hoc testing. Correlations between mechanical and biochemical parameters were assessed by linear regressions. Significance was set to P pelvic floor muscle stiffness did not differ from virgins (P > .3). A substantial increase in collagen V in coccygeus and pubocaudalis was observed in late-pregnant, compared with virgin, animals, (P pelvic floor muscles (P pelvic floor muscles, the tibialis anterior was unaltered by pregnancy. CONCLUSIONS In contrast to other pelvic tissues, pelvic floor muscle stiffness increased in pregnancy, returning to prepregnancy state post-partum. This adaptation may shield myofibers from excessive mechanical strain during parturition. Biochemical alterations in pelvic floor muscle extracellular matrix

  18. Density induced phase transitions in the Schwinger model. A study with matrix product states

    Energy Technology Data Exchange (ETDEWEB)

    Banuls, Mari Carmen; Cirac, J. Ignacio; Kuehn, Stefan [Max-Planck-Institut fuer Quantenoptik (MPQ), Garching (Germany); Cichy, Krzysztof [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik; Adam Mickiewicz Univ., Poznan (Poland). Faculty of Physics; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC

    2017-02-15

    We numerically study the zero temperature phase structure of the multiflavor Schwinger model at nonzero chemical potential. Using matrix product states, we reproduce analytical results for the phase structure for two flavors in the massless case and extend the computation to the massive case, where no analytical predictions are available. Our calculations allow us to locate phase transitions in the mass-chemical potential plane with great precision and provide a concrete example of tensor networks overcoming the sign problem in a lattice gauge theory calculation.

  19. Renal cell neoplasias: reversion-inducing cysteine-rich protein with Kazal motifs discriminates tumor subtypes, while extracellular matrix metalloproteinase inducer indicates prognosis.

    Science.gov (United States)

    Rabien, Anja; Stephan, Carsten; Kilic, Ergin; Weichert, Wilko; Kristiansen, Glen; Miller, Kurt; Jung, Klaus; Erbersdobler, Andreas

    2013-10-16

    Matrix metalloproteinases can promote invasion and metastasis, which are very frequent in renal cell carcinoma even at the time of diagnosis. Knowing the reversion-inducing cysteine-rich protein with Kazal motifs (RECK) as an inhibitor of matrix metalloproteinases and the extracellular matrix metalloproteinase inducer (EMMPRIN) protein as inducer, we aimed to determine their expression, localization and possible antagonistic action in the pathogenesis and progression of renal cell tumors in a retrospective study. Tumor and adjacent normal tissues of 395 nephrectomized patients were immunostained for RECK and EMMPRIN on a tissue microarray. RECK strongly decreased in renal cell carcinoma compared to normal counterparts (Wilcoxon signed rank test, P<0.001), and it discriminated tumor entities showing the highest expression in oncocytomas. EMMPRIN, however, could be significantly correlated to pT stage and Fuhrman grading (Spearman's correlation coefficient rs=0.289 and rs=0.382, respectively). Higher expression of EMMPRIN was associated with decreased overall survival in Kaplan-Meier analysis (P<0.001), and the EMMPRIN level could independently predict survival for cases without metastasis and involvement of lymph nodes. Decreased RECK expression was confirmed by Western blotting in tissue of eight normal/tumor matches of patients after radical nephrectomy, whereas the EMMPRIN pattern appeared to be heterogeneous. We propose RECK down regulation in renal cell carcinoma to be an early event that facilitates tumor formation and progression. EMMPRIN, however, as a prognostic tumor marker, increases only when aggressiveness is proceeding and could add an additional step to invasive properties of renal cell carcinoma.

  20. An R-matrix study of electron induced processes in BF3 plasma

    Science.gov (United States)

    Gupta, Dhanoj; Chakrabarti, Kalyan; Yoon, Jung-Sik; Song, Mi-Young

    2017-12-01

    An R-matrix formalism is used to study electron collision with the BF3 molecule using Quantemol-N, a computational system for electron molecule collisions which uses the molecular R-matrix method. Several target models are tested for BF3 in its equilibrium geometry, and the results are presented for the best model. Scattering calculations are then performed to yield resonance parameters, elastic, differential, excitation, and momentum transfer cross sections. The results for all the cross sections are compared with the experimental and theoretical data, and a good agreement is obtained. The resonances have been detected at 3.79 and 13.58 eV, with the ionization threshold being 15.7 eV. We have also estimated the absolute dissociative electron attachment (DEA) cross section for the F- ion production from BF3, which is a maiden attempt. The peak of the DEA is at around 13.5 eV, which is well supported by the resonance detected at 13.58 eV. The cross sections reported here find a variety of applications in the plasma technology.

  1. Matrix metalloproteinase (MMP) 9 transcription in mouse brain induced by fear learning.

    Science.gov (United States)

    Ganguly, Krishnendu; Rejmak, Emilia; Mikosz, Marta; Nikolaev, Evgeni; Knapska, Ewelina; Kaczmarek, Leszek

    2013-07-19

    Memory formation requires learning-based molecular and structural changes in neurons, whereas matrix metalloproteinase (MMP) 9 is involved in the synaptic plasticity by cleaving extracellular matrix proteins and, thus, is associated with learning processes in the mammalian brain. Because the mechanisms of MMP-9 transcription in the brain are poorly understood, this study aimed to elucidate regulation of MMP-9 gene expression in the mouse brain after fear learning. We show here that contextual fear conditioning markedly increases MMP-9 transcription, followed by enhanced enzymatic levels in the three major brain structures implicated in fear learning, i.e. the amygdala, hippocampus, and prefrontal cortex. To reveal the role of AP-1 transcription factor in MMP-9 gene expression, we have used reporter gene constructs with specifically mutated AP-1 gene promoter sites. The constructs were introduced into the medial prefrontal cortex of neonatal mouse pups by electroporation, and the regulation of MMP-9 transcription was studied after contextual fear conditioning in the adult animals. Specifically, -42/-50- and -478/-486-bp AP-1 binding motifs of the mouse MMP-9 promoter sequence have been found to play a major role in MMP-9 gene activation. Furthermore, increases in MMP-9 gene promoter binding by the AP-1 transcription factor proteins c-Fos and c-Jun have been demonstrated in all three brain structures under investigation. Hence, our results suggest that AP-1 acts as a positive regulator of MMP-9 transcription in the brain following fear learning.

  2. Large Magnetovolume Effect Induced by Embedding Ferromagnetic Clusters into Antiferromagnetic Matrix of Cobaltite Perovskite.

    Science.gov (United States)

    Miao, Ping; Lin, Xiaohuan; Koda, Akihiro; Lee, Sanghyun; Ishikawa, Yoshihisa; Torii, Shuki; Yonemura, Masao; Mochiku, Takashi; Sagayama, Hajime; Itoh, Shinichi; Ikeda, Kazutaka; Otomo, Toshiya; Wang, Yinxia; Kadono, Ryosuke; Kamiyama, Takashi

    2017-07-01

    Materials that show negative thermal expansion (NTE) have significant industrial merit because they can be used to fabricate composites whose dimensions remain invariant upon heating. In some materials, NTE is concomitant with the spontaneous magnetization due to the magnetovolume effect (MVE). Here the authors report a new class of MVE material; namely, a layered perovskite PrBaCo 2 O 5.5+ x (0 ≤ x ≤ 0.41), in which strong NTE [β ≈ -3.6 × 10 -5 K -1 (90-110 K) at x = 0.24] is triggered by embedding ferromagnetic (F) clusters into the antiferromagnetic (AF) matrix. The strongest MVE is found near the boundary between F and AF phases in the phase diagram, indicating the essential role of competition between the F-clusters and the AF-matrix. Furthermore, the MVE is not limited to the PrBaCo 2 O 5.5+ x but is also observed in the NdBaCo 2 O 5.5+ x . The present study provides a new approach to obtaining MVE and offers a path to the design of NTE materials. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Host-Parasite Interaction: Parasite-Derived and -Induced Proteases That Degrade Human Extracellular Matrix

    Directory of Open Access Journals (Sweden)

    Carolina Piña-Vázquez

    2012-01-01

    Full Text Available Parasitic protozoa are among the most important pathogens worldwide. Diseases such as malaria, leishmaniasis, amoebiasis, giardiasis, trichomoniasis, and trypanosomiasis affect millions of people. Humans are constantly threatened by infections caused by these pathogens. Parasites engage a plethora of surface and secreted molecules to attach to and enter mammalian cells. The secretion of lytic enzymes by parasites into host organs mediates critical interactions because of the invasion and destruction of interstitial tissues, enabling parasite migration to other sites within the hosts. Extracellular matrix is a complex, cross-linked structure that holds cells together in an organized assembly and that forms the basement membrane lining (basal lamina. The extracellular matrix represents a major barrier to parasites. Therefore, the evolution of mechanisms for connective-tissue degradation may be of great importance for parasite survival. Recent advances have been achieved in our understanding of the biochemistry and molecular biology of proteases from parasitic protozoa. The focus of this paper is to discuss the role of protozoan parasitic proteases in the degradation of host ECM proteins and the participation of these molecules as virulence factors. We divide the paper into two sections, extracellular and intracellular protozoa.

  4. Change in cell shape is required for matrix metalloproteinase-induced epithelial-mesenchymal transition of mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Celeste M.; Khauv, Davitte; Bissell, Mina J.; Radisky, Derek C.

    2008-06-26

    Cell morphology dictates response to a wide variety of stimuli, controlling cell metabolism, differentiation, proliferation, and death. Epithelial-mesenchymal transition (EMT) is a developmental process in which epithelial cells acquire migratory characteristics, and in the process convert from a 'cuboidal' epithelial structure into an elongated mesenchymal shape. We had shown previously that matrix metalloproteinase-3 (MMP3) can stimulate EMT of cultured mouse mammary epithelial cells through a process that involves increased expression of Rac1b, a protein that stimulates alterations in cytoskeletal structure. We show here that cells treated with MMP-3 or induced to express Rac1b spread to cover a larger surface, and that this induction of cell spreading is a requirement of MMP-3/Rac1b-induced EMT. We find that limiting cell spreading, either by increasing cell density or by culturing cells on precisely defined micropatterned substrata, blocks expression of characteristic markers of EMT in cells treated with MMP-3. These effects are not caused by general disruptions in cell signaling pathways, as TGF-{beta}-induced EMT is not affected by similar limitations on cell spreading. Our data reveal a previously unanticipated cell shape-dependent mechanism that controls this key phenotypic alteration and provide insight into the distinct mechanisms activated by different EMT-inducing agents.

  5. Adipokines induce catabolism of newly synthesized matrix in cartilage and meniscus tissues.

    Science.gov (United States)

    Nishimuta, James F; Levenston, Marc E

    Altered synovial levels of various adipokines (factors secreted by fat as well as other tissues) have been associated with osteoarthritis (OA) onset and progression. However, the metabolic effects of adipokines on joint tissues, in particular the fibrocartilaginous menisci, are not well understood. This study investigated effects of several adipokines on release of recently synthesized extracellular matrix in bovine cartilage and meniscus tissue explants. After labeling newly synthesized proteins and sulfated glycosaminoglycans (sGAGs) with 3 H-proline and 35 S-sulfate, respectively; bovine cartilage and meniscus tissue explants were cultured for 6 days in basal medium (control) or media supplemented with adipokines (1 µg/ml of leptin, visfatin, adiponectin, or resistin) or 20 ng/ml interleukin-1 (IL-1). Release of radiolabel and sGAG to the media during culture and the final explant water, DNA, sGAG, and retained radiolabel were measured. Matrix metalloproteinase (MMP-2) and MMP-3 activities were assessed using gelatin and casein zymography, respectively. Water and DNA contents were not significantly altered by any treatment. Visfatin, adiponectin, resistin, and IL-1 stimulated sGAG release from meniscus, whereas only IL-1 stimulated sGAG release from cartilage. Release of 3 H and 35 S was stimulated not only by resistin and IL-1 in meniscus but also by IL-1 in cartilage. Retained 3 H was unaltered by any treatment, while retained 35 S was reduced by visfatin, resistin, and IL-1 in meniscus and by only IL-1 in cartilage. Resistin and IL-1 elevated active MMP-2 and total MMP-3 in meniscus, whereas cartilage MMP-3 activity was elevated by only IL-1. Resistin stimulated rapid and extensive catabolism of meniscus tissue, similar to IL-1, whereas adipokines minimally affected cartilage. Release of newly synthesized matrix was similar to overall release in both tissues. These observations provide further indications that meniscal tissue is more sensitive to pro

  6. Spontaneous and cytokine induced expression and activity of matrix metalloproteinases in human colonic epithelium

    DEFF Research Database (Denmark)

    Pedersen, G; Saermark, T; Kirkegaard, T

    2009-01-01

    levels in cells from inflamed IBD mucosa. MMP-2 and -8 mRNA were expressed inconsistently and MMP-11, -13 and -14 mRNA undetectable. Proteolytic MMP activity was detected in CEC supernatants and the level was increased significantly in inflamed IBD epithelium. The enzyme activity was inhibited strongly......Matrix metalloproteinases (MMPs) have been implicated in tissue damage associated with inflammatory bowel disease (IBD).As the role of the intestinal epithelium in this process is unknown, we determined MMP expression and enzyme activity in human colonic epithelial cells (CEC). MMP mRNA expression...... was assessed by reverse transcription-polymerase chain reaction in HT-29 and DLD-1 cells and in CEC isolated from biopsies from IBD and control patients. Total MMP activity in the cells was measured by a functional assay, based on degradation of a fluorescent synthetic peptide containing the specific bond...

  7. Radiation-induced evolution of austenite matrix in silicon-modified AISI 316 alloys

    International Nuclear Information System (INIS)

    Garner, F.A.; Brager, H.R.

    1980-01-01

    The microstructures of a series of silicon-modified AISI 316 alloys irradiated to fast neutron fluences of about 2-3 and 10 x 10 22 n/cm 2 (E > 0.1 MeV at temperatures ranging from 400 0 C to 600 0 C have been examined. The irradiation of AISI 316 leads to an extensive repartition of several elements, particularly nickel and silicon, between the matrix and various precipitate phases. The segregation of nickel at void and grain boundary surfaces at the expense of other faster-diffusing elements is a clear indication that one of the mechanisms driving the microchemical evolution is the Inverse Kirkendall effect. There is evidence that at one sink this mechanism is in competition with the solute drag process associated with interstitial gradients

  8. Repair Potential of Matrix-Induced Bone Marrow Aspirate Concentrate and Matrix-Induced Autologous Chondrocyte Implantation for Talar Osteochondral Repair: Patterns of Some Catabolic, Inflammatory, and Pain Mediators.

    Science.gov (United States)

    Desando, Giovanna; Bartolotti, Isabella; Vannini, Francesca; Cavallo, Carola; Castagnini, Francesco; Buda, Roberto; Giannini, Sandro; Mosca, Massimiliano; Mariani, Erminia; Grigolo, Brunella

    2017-01-01

    The low regenerative potential of cartilage contributed to the development of different cell therapies aimed to improve the clinical outcome in young patients with Osteochondral Lesions of the Talus (OLT). This study is designed to assess the regenerative potential of autologous matrix-induced Bone Marrow Aspirate Concentrate (mBMAC) and matrix-induced Autologous Chondrocyte Implantation (mACI) evaluating, on a small number of osteochondral biopsies, the expression of some catabolic, inflammatory, and pain mediators. Twenty-two patients with OLT were analyzed in this study; 7 were treated with mACI and 15 with mBMAC. Informed consent was obtained from all the patients. Clinical assessments were performed pre-operatively and at 12, 24, and 36 months after surgery using the American Orthopedic Foot and Ankle Society (AOFAS). Histology and immunohistochemistry were used to assess cartilage repair at 24 months. Data were analyzed using non-parametric Wilcoxon-Mann-Whitney and Spearman tests. A remarkable improvement in AOFAS score was noticed for both treatments up to 36 months; however, patients treated with mACI reported the best AOFAS score. Various degrees of tissue remodeling were observed by histological analysis for both cell strategies. However, mBMAC treatment showed a higher expression of some fibrous and hypertrophic markers compared to mACI group. A mild positivity for nerve growth factor, as pain mediator, was noticed for both treatments.M. Our findings demonstrated the best histological and clinical results following mACI treatment since different fibrotic and hypertrophic features were evident in the mBMAC group at 24-month follow-up.

  9. Quantitative methods for compensation of matrix effects and self-absorption in Laser Induced Breakdown Spectroscopy signals of solids

    Science.gov (United States)

    Takahashi, Tomoko; Thornton, Blair

    2017-12-01

    This paper reviews methods to compensate for matrix effects and self-absorption during quantitative analysis of compositions of solids measured using Laser Induced Breakdown Spectroscopy (LIBS) and their applications to in-situ analysis. Methods to reduce matrix and self-absorption effects on calibration curves are first introduced. The conditions where calibration curves are applicable to quantification of compositions of solid samples and their limitations are discussed. While calibration-free LIBS (CF-LIBS), which corrects matrix effects theoretically based on the Boltzmann distribution law and Saha equation, has been applied in a number of studies, requirements need to be satisfied for the calculation of chemical compositions to be valid. Also, peaks of all elements contained in the target need to be detected, which is a bottleneck for in-situ analysis of unknown materials. Multivariate analysis techniques are gaining momentum in LIBS analysis. Among the available techniques, principal component regression (PCR) analysis and partial least squares (PLS) regression analysis, which can extract related information to compositions from all spectral data, are widely established methods and have been applied to various fields including in-situ applications in air and for planetary explorations. Artificial neural networks (ANNs), where non-linear effects can be modelled, have also been investigated as a quantitative method and their applications are introduced. The ability to make quantitative estimates based on LIBS signals is seen as a key element for the technique to gain wider acceptance as an analytical method, especially in in-situ applications. In order to accelerate this process, it is recommended that the accuracy should be described using common figures of merit which express the overall normalised accuracy, such as the normalised root mean square errors (NRMSEs), when comparing the accuracy obtained from different setups and analytical methods.

  10. AMP-Activated Protein Kinase Alleviates Extracellular Matrix Accumulation in High Glucose-Induced Renal Fibroblasts through mTOR Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Xia Luo

    2015-01-01

    Full Text Available Background/Aims: Extracellular matrix accumulation contributes significantly to the pathogenesis of diabetic nephropathy. Although AMP-activated protein kinase (AMPK has been found to inhibit extracellular matrix synthesis by experiments in vivo and vitro, its role in alleviating the deposition of extracellular matrix in renal interstitial fibroblasts has not been well defined. Methods: Currently, we conducted this study to investigate the effects of AMPK on high glucose-induced extracellular matrix synthesis and involved intracellular signaling pathway by using western blot in the kidney fibroblast cell line (NRK-49f. Results: Collagen IV protein levels were significantly increased by high glucose in a time-dependent manner. This was associated with a decrease in Thr72 phosphorylation of AMPK and an increase in phosphorylation of mTOR on Ser2448. High glucose-induced extracellular matrix accumulation and mTOR activation were significantly inhibited by the co-treatment of rAAV-AMPKα1312 (encoding constitutively active AMPKα1 whereas activated by r-AAV-AMPKα1D157A (encoding dominant negative AMPKα1. In cultured renal fibroblasts, overexpression of AMPKα1D157A upregulated mTOR signaling and matrix synthesis, which were ameliorated by co-treatment with the inhibitor of mTOR, rapamycin. Conclusion: Collectively, these findings indicate that AMPK exerts renoprotective effects by inhibiting the accumulation of extracellular matrix through mTOR signaling pathway.

  11. Angiotensin II Facilitates Matrix Metalloproteinase-9-Mediated Myosin Light Chain Kinase Degradation in Pressure Overload-Induced Cardiac Hypertrophy

    Directory of Open Access Journals (Sweden)

    Shun Wang

    2017-12-01

    Full Text Available Background/Aims: Angiotensin II (Ang II has been shown to promote cardiac remodeling during the process of hypertrophy. Myosin light chain kinase (MLCK, a specific kinase for the phosphorylation of myosin light chain 2 (MLC2, plays an important role in regulating cardiac muscle contraction and hypertrophy. However, whether Ang II could facilitate cardiac hypertrophy by altering the expression of MLCK remains unclear. This study aimed to investigate this effect and the underlying mechanisms. Methods: Cardiac hypertrophy was induced via pressure overload in rats, which were then evaluated via histological and biochemical measurements and echocardiography. Angiotensin-converting enzyme inhibitor (ACEI was used to inhibit Ang II. Neonatal rat cardiomyocytes were stimulated with Ang II to induce hypertrophy and were treated with a matrix metalloproteinase 9 (MMP9 inhibitor. Myocyte hypertrophy was evaluated using immunofluorescence and qRT-PCR. Degradation of recombinant human MLCK by recombinant human MMP9 was tested using a cleavage assay. The expression levels of MLCK, MLC2, phospho-myosin light chain 2 (p-MLC2, myosin phosphatase 2 (MYPT2, and calmodulin (CaM were measured using western blotting. Results: ACEI improved cardiac function and remodeling and increased the levels of MLCK and p-MLC2 as well as reduced the expression of MMP9 in pressure overload-induced cardiac hypertrophy. Moreover, the MMP9 inhibitor alleviated myocyte hypertrophy and upregulated the levels of MLCK and p-MLC2 in Ang II-induced cardiomyocyte hypertrophy. Recombinant human MLCK was concentration- and time-dependently degraded by recombinant human MMP9 in vitro, and this process was prevented by the MMP9 inhibitor. Conclusion: Our results suggest that Ang II is involved in the degradation of MLCK in pressure overload-induced cardiac hypertrophy and that this process was mediated by MMP9.

  12. Qualitative analysis of teeth and evaluation of amalgam elements penetration into dental matrix using laser induced breakdown spectroscopy.

    Science.gov (United States)

    Gazmeh, Meisam; Bahreini, Maryam; Tavassoli, Seyed Hassan; Asnaashari, Mohammad

    2015-01-01

    In this study, laser induced breakdown spectroscopy (LIBS) is used for qualitative analysis of healthy and carious teeth. The technique of laser ablation is receiving increasing attention for applications in dentistry, specifically for the treatment of teeth such as drilling of micro-holes and plaque removal. A quality-switched (Q-switched) Neodymium-Doped Yttrium Aluminium Garnet (Nd:YAG) laser operating at wavelength of 1064 nm, pulse energy of 90 mJ/pulse, repetition rate of 2Hz and pulse duration of 6 ns was used in this analysis. In the process of ablation a luminous micro-plasma is normally generated which may be exploited for on-line elemental analysis via laser induced breakdown spectroscopy technique. We propose laser induced breakdown spectroscopy as a rapid, in situ and easy method for monitoring drilling process. The results of elemental analysis show the presence of some trace elements in teeth including P, Ca, Mg, Zn, K, Sr, C, Na, H, O and the permeability of some amalgam (teeth filling materials) elements including Hg, Ag, Cu and Sn into dental matrix. This study addresses the ability of LIBS in elemental analysis of teeth and its feasibility in acute identification of healthy and carious teeth during drilling process for future clinical applications.

  13. Skip Regulates TGF-β1-Induced Extracellular Matrix Degrading Proteases Expression in Human PC-3 Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Victor Villar

    2013-01-01

    Full Text Available Purpose. To determine whether Ski-interacting protein (SKIP regulates TGF-β1-stimulated expression of urokinase-type plasminogen activator (uPA, matrix metalloproteinase-9 (MMP-9, and uPA Inhibitor (PAI-1 in the androgen-independent human prostate cancer cell model. Materials and Methods. PC-3 prostate cancer cell line was used. The role of SKIP was evaluated using synthetic small interference RNA (siRNA compounds. The expression of uPA, MMP-9, and PAI-1 was evaluated by zymography assays, RT-PCR, and promoter transactivation analysis. Results. In PC-3 cells TGF-β1 treatment stimulated uPA, PAI-1, and MMP-9 expressions. The knockdown of SKIP in PC-3 cells enhanced the basal level of uPA, and TGF-β1 treatment inhibited uPA production. Both PAI-1 and MMP-9 production levels were increased in response to TGF-β1. The ectopic expression of SKIP inhibited both TGF-β1-induced uPA and MMP-9 promoter transactivation, while PAI-1 promoter response to the factor was unaffected. Conclusions. SKIP regulates the expression of uPA, PAI-1, and MMP-9 stimulated by TGF-β1 in PC-3 cells. Thus, SKIP is implicated in the regulation of extracellular matrix degradation and can therefore be suggested as a novel therapeutic target in prostate cancer treatment.

  14. Molecular mechanisms of the 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced inverted U-shaped dose responsiveness in anchorage independent growth and cell proliferation of human breast epithelial cells with stem cell characteristics

    International Nuclear Information System (INIS)

    Ahn, Nam-Shik; Hu, Hongbo; Park, Jin-Sung; Park, Joon-Suk; Kim, Jong-Sik; An, Sungwhan; Kong, Gu; Aruoma, Okezie I.; Lee, Yong-Soon; Kang, Kyung-Sun

    2005-01-01

    Although 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has a variety of carcinogenic and noncarcinogenic effects in experimental animals, its role in human carcinogenicity remain controversial. A simian virus 40-immortalized cell line from normal human breast epithelial cells with stem cells and luminal characteristics (M13SV1) was used to study whether TCDD can induce AIG positive colony formation and cause increased cell numbers in a inverted U-shaped dose-response manner. TCDD activated Akt, ERK2, and increased the expression of CYP1A1, PAI-2, IL-lb mRNA, and ERK2 protein levels. TCDD was able to increased phosphorylation and expression of ERK2 in same dose-response manner as AIG positive colony formation. Thus, TCDD induced tumorigenicity in M13SV1, possibly through the phosphorylation of ERK2 and/or Akt. Further, cDNA microarray with 7448 sequence-verified clones was used to profile various gene expression patterns after treatment of TCDD. Three clear patterns could be delineated: genes that were dose-dependently up-regulated, genes expressed in either U-shape and/or inverted U-shape. The fact that these genes are intrinsically related to breast epithelial cell proliferation and survival clearly suggests that they may be involved in the TCDD-induced breast tumorigenesis

  15. Extracellular matrix metabolism disorder induced by mechanical strain on human parametrial ligament fibroblasts.

    Science.gov (United States)

    Min, Jie; Li, Bingshu; Liu, Cheng; Guo, Wenjun; Hong, Shasha; Tang, Jianming; Hong, Li

    2017-05-01

    Pelvic organ prolapse (POP) is a global health problem that may seriously impact the quality of life of the sufferer. The present study aimed to investigate the potential mechanisms underlying alterations in extracellular matrix (ECM) metabolism in the pathogenesis of POP, by investigating the expression of ECM components in human parametrial ligament fibroblasts (hPLFs) subject to various mechanical strain loads. Fibroblasts derived from parametrial ligaments were cultured from patients with POP and without malignant tumors, who underwent vaginal hysterectomy surgery. Fibroblasts at generations 3‑6 of exponential phase cells were selected, and a four‑point bending device was used for 0, 1,333 or 5,333 µ mechanical loading of cells at 0.5 Hz for 4 h. mRNA and protein expression levels of collagen type I α 1 chain (COL1A1), collagen type III α 1 chain (COL3A1), elastin, matrix metalloproteinase (MMP) ‑2 and ‑9, and transforming growth factor (TGF)‑β1 were detected by reverse transcription‑quantitative polymerase chain reaction and western blotting, respectively. Under increased mechanical strain (5,333 µ), mRNA and protein expression levels of COL1A1, COL3A1 elastin and TGF‑β1 decreased, particularly COL1A1; however, mRNA and protein expression levels of MMP‑2 and ‑9 were significantly increased, compared with the control group (0 µ strain). Following 1,333 µ mechanical strain, mRNA and protein expression levels of COL1A1, COL3A1 elastin and MMP‑2 increased, and MMP‑9 decreased, whereas no significant differences were observed in TGF‑β1 mRNA and protein expression levels. In conclusion, ECM alterations may be involved in pathogenesis of POP, with decreased synthesis and increased degradation of collagen and elastin. Furthermore, the TGF‑β1 signaling pathway may serve an important role in this process and thus may supply a new target and strategy for understanding the etiology and therapy of POP.

  16. Combined role of type IX collagen and cartilage oligomeric matrix protein in cartilage matrix assembly: Cartilage oligomeric matrix protein counteracts type IX collagen-induced limitation of cartilage collagen fibril growth in mouse chondrocyte cultures

    NARCIS (Netherlands)

    Blumbach, K.; Bastiaansen-Jenniskens, Y.M.; Groot, J. de; Paulsson, M.; Osch, G.J.V.M. van; Zaucke, F.

    2009-01-01

    Objective. Defects in the assembly and composition of cartilage extracellular matrix are likely to result in impaired matrix integrity and increased susceptibility to cartilage degeneration. The aim of this study was to determine the functional interaction of the collagen fibril-associated proteins

  17. Ion beam-induced shaping of Ni nanoparticles embedded in a silica matrix: from spherical to prolate shape

    Directory of Open Access Journals (Sweden)

    Avasthi Devesh

    2011-01-01

    Full Text Available Abstract Present work reports the elongation of spherical Ni nanoparticles (NPs parallel to each other, due to bombardment with 120 MeV Au+9 ions at a fluence of 5 × 1013 ions/cm2. The Ni NPs embedded in silica matrix have been prepared by atom beam sputtering technique and subsequent annealing. The elongation of Ni NPs due to interaction with Au+9 ions as investigated by cross-sectional transmission electron microscopy (TEM shows a strong dependence on initial Ni particle size and is explained on the basis of thermal spike model. Irradiation induces a change from single crystalline nature of spherical particles to polycrystalline nature of elongated particles. Magnetization measurements indicate that changes in coercivity (Hc and remanence ratio (Mr/Ms are stronger in the ion beam direction due to the preferential easy axis of elongated particles in the beam direction.

  18. Matrix effects in the determination of phosphorus and sodium by proton-induced prompt gamma spectrometry

    International Nuclear Information System (INIS)

    Olivier, C.; Morland, H.J.

    1990-01-01

    By measuring the yield of prompt gamma rays, induced by accelerated charged particles, the ratio of the ranges in sample and standard can be used in the average cross-section method to determine elemental or isotopic compositions. By spiking the sample with a known amount of a compound containing a non-analyte element (absent in the sample), the appropriate range in the sample can be determined by measuring the prompt gamma rays induced in the non-analyte spike. With lithium compounds as the non-analyte spike, sodium and phosphorus were determined in ivory. The method was tested by analysing the standard reference materials SRM 91, SRM 120c, and SRM 694. 2 figs., 5 tabs., 10 refs

  19. Photoluminescence induced by Si implantation into Si{sub 3}N{sub 4} matrix

    Energy Technology Data Exchange (ETDEWEB)

    Bregolin, F.L. [Instituto de Fisica, Universidade Federal Rio Grande do Sul, C.P. 15051, 91501-970 Porto Alegre, RS (Brazil); Behar, M. [Instituto de Fisica, Universidade Federal Rio Grande do Sul, C.P. 15051, 91501-970 Porto Alegre, RS (Brazil)], E-mail: behar@if.ufrgs.br; Sias, U.S. [Centro Federal de Educacao Tecnologica de Pelotas, 96015-370, RS (Brazil); Moreira, E.C. [Universidade Federal do Pampa - UNIPAMPA, Campus Bage, 96400-970 Bage, RS (Brazil)

    2009-05-01

    Up to the present, photoluminescence (PL) was obtained from near stoichiometric or amorphous Si nitride films (SiN{sub x}) after annealing at high temperatures. As a consequence, the existence of PL bands has been reported in the 400-900 nm range. In the present contribution, we report the first PL results obtained by Si implantation into a stoichiometric 380 nm Si{sub 3}N{sub 4} film. The Si excess is obtained by a 170 keV Si implantation at different temperatures with a fluence of {phi} = 10{sup 17} Si/cm{sup 2}. Further, we have annealed the samples in a temperature range between 350 and 900 deg. C in order to form the Si precipitates. PL measurements were done using an Ar laser as an excitation source, and a broad PL band basically centered at 910 nm was obtained. We show that the best annealing condition is obtained at T{sub a} = 475 deg. C for the samples implanted at 200 deg. C, with a PL yield 20% higher than the obtained at room temperature implantation. Finally, we have varied the implantation fluence and, consequently, the Si nanocrystals size. However, no variation was observed nor in the position neither in the intensity of the PL band. We concluded that the PL emission is due to radiative states at the matrix and the Si nanocrystals interface, as previously suggested in the literature.

  20. Castor oil polymer induces bone formation with high matrix metalloproteinase-2 expression.

    Science.gov (United States)

    Saran, Wallace Rocha; Chierice, Gilberto Orivaldo; da Silva, Raquel Assed Bezerra; de Queiroz, Alexandra Mussolino; Paula-Silva, Francisco Wanderley Garcia; da Silva, Léa Assed Bezerra

    2014-02-01

    The aim of this study was to evaluate the modulation of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) expression in newly formed bone tissue at the interface between implants derived from castor oil (Ricinus communis) polymer and the tibia medullary canal. Forty-four rabbits were assigned to either Group 1 (n = 12; control) or Group 2 (n = 30), which had the tibial medullary canals reamed bilaterally and filled with polymer. CT scans showed no space between the material surface and the bone at the implant/bone marrow interface, and the density of the tissues at this interface was similar to the density measured of other regions of the bone. At 90 days postimplantation, the interface with the polymer presented a thick layer of newly formed bone tissue rich in osteocytes. This tissue exhibited ongoing maturation at 120 and 150 days postimplantation. Overall, bone remodeling process was accompanied by positive modulation of MMP-2 and low MMP-9 expression. Differently, in control group, the internal surface close to the medullary canal was lined by osteoblasts, followed by a bone tissue zone with few lacunae filled with osteocytes. Maturation of the tissue of the medullary internal surface occurred in the inner region, with the bone being nonlamellar. © 2013 Wiley Periodicals, Inc.

  1. Viability of chondrocytes seeded onto a collagen I/III membrane for matrix-induced autologous chondrocyte implantation.

    Science.gov (United States)

    Hindle, Paul; Hall, Andrew C; Biant, Leela C

    2014-11-01

    Cell viability is crucial for effective cell-based cartilage repair. The aim of this study was to determine the effect of handling the membrane during matrix-induced autologous chondrocyte implantation surgery on the viability of implanted chondrocytes. Images were acquired under five conditions: (i) Pre-operative; (ii) Handled during surgery; (iii) Cut edge; (iv) Thumb pressure applied; (v) Heavily grasped with forceps. Live and dead cell stains were used. Images were obtained for cell counting and morphology. Mean cell density was 6.60 × 10(5) cells/cm(2) (5.74-7.11 × 10(5) ) in specimens that did not have significant trauma decreasing significantly in specimens that had been grasped with forceps (p < 0.001) or cut (p = 0.004). Cell viability on delivery grade membrane was 75.1%(72.4-77.8%). This dropped to 67.4%(64.1-69.7%) after handling (p = 0.002), 56.3%(51.5-61.6%) after being thumbed (p < 0.001) and 28.8%(24.7-31.2%) after crushing with forceps (p < 0.001). When cut with scissors there was a band of cell death approximately 275 µm in width where cell viability decreased to 13.7%(10.2-18.2%, p < 0.001). Higher magnification revealed cells without the typical rounded appearance of chondrocytes. We found that confocal laser-scanning microscope (CLSM) can be used to quantify and image the fine morphology of cells on a matrix-induced autologous chondrocyte implantation (MACI) membrane. Careful handling of the membrane is essential to minimise chondrocyte death during surgery. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  2. PGF2alpha induced differential expression of genes involved in turnover of extracellular matrix in rat decidual cells

    Directory of Open Access Journals (Sweden)

    Callegari Eduardo A

    2005-01-01

    Full Text Available Abstract In the rat, the decidual tissue is an important component for maternal recognition of pregnancy. Decidualization can be induced by either the implantation of the blastocyst or by artificial stimuli. The process of decidua formation or decidualization, is characterized by growth and differentiation of endometrial stromal cells. Prostaglandin F2alpha (PGF2α has been shown to be involved in inhibition of implantation, alteration of embryo development, induction of luteal regression, and the mediation of pregnancy loss induced by microorganism infections. In order to establish a direct role for PGF2α in decidual function, we have evaluated its effects on the expression of an extensive array of genes using primary decidual cell culture. Upon treatment with PGF2α sixty genes were significantly down-regulated whereas only six genes were up-regulated (from a total of 1176 genes studied. Interestingly, the majority of the genes inhibited by PGF2α are either directly or indirectly involved in the turnover of the extracellular matrix (ECM. Genes such as gelatinase A (MMP2, cathepsin L, tissue inhibitor metalloproteinases 2 (TIMP2 and 3 (TIMP3, plasminogen activator inhibitor1 (PAI1, tissue type plasminogen activator (tPA, urokinase plasminogen activator (tPA, endothelin 1, calponin, carboxypeptidase D and calponin acidic were down regulated. The opposite effect was observed for prostromelysin 53 kDa (proMMP3, plasma proteinase I alpha and alpha 1 antiproteinase, all of which were significantly up-regulated by PGF2α. The results strongly suggest that the abortificient role of elevated levels of PGF2α after implantation is due, in large part, to inhibition of genes involved in the normal turnover of the extracellular matrix necessary for decidual formation.

  3. Calibration approach for extremely variable laser induced plasmas and a strategy to reduce the matrix effect in general

    Science.gov (United States)

    Lazic, V.; De Ninno, A.

    2017-11-01

    The laser induced plasma spectroscopy was applied on particles attached on substrate represented by a silica wafer covered with a thin oil film. The substrate itself weakly interacts with a ns Nd:YAG laser (1064 nm) while presence of particles strongly enhances the plasma emission, here detected by a compact spectrometer array. Variations of the sample mass from one laser spot to another exceed one order of magnitude, as estimated by on-line photography and the initial image calibration for different sample loadings. Consequently, the spectral lines from particles show extreme intensity fluctuations from one sampling point to another, between the detection threshold and the detector's saturation in some cases. In such conditions the common calibration approach based on the averaged spectra, also when considering ratios of the element lines i.e. concentrations, produces errors too large for measuring the sample compositions. On the other hand, intensities of an analytical and the reference line from single shot spectra are linearly correlated. The corresponding slope depends on the concentration ratio and it is weakly sensitive to fluctuations of the plasma temperature inside the data set. A use of the slopes for constructing the calibration graphs significantly reduces the error bars but it does not eliminate the point scattering caused by the matrix effect, which is also responsible for large differences in the average plasma temperatures among the samples. Well aligned calibration points were obtained after identifying the couples of transitions less sensitive to variations of the plasma temperature, and this was achieved by simple theoretical simulations. Such selection of the analytical lines minimizes the matrix effect, and together with the chosen calibration approach, allows to measure the relative element concentrations even in highly unstable laser induced plasmas.

  4. Troglitazone Induces Extracellular Matrix and Cytoskeleton Remodeling in Mouse Collecting Duct Cells

    OpenAIRE

    Corinaldi, Jaime; Nasrallah, Rania; Clark, Jordan; Paris, Geneviève; Miura, Pedro; Jasmin, Bernard J.; Hébert, Richard L.

    2012-01-01

    Peroxisome proliferator-activated receptor (PPAR γ ) has been shown to have a protective role in the nephron through its ability to inhibit a transforming growth factor- (TGF- β ) mediated fibrotic response. In contrast, PPAR γ was also shown to induce a mesenchymal transformation in epithelial intestinal cells. A fibrotic response in the collecting duct has only recently been established; however, the entire collecting duct has not been fully examined. Inner medullary collecting duct cells (...

  5. Dioxin-induced up-regulation of the active form of vitamin D is the main cause for its inhibitory action on osteoblast activities, leading to developmental bone toxicity

    International Nuclear Information System (INIS)

    Nishimura, Noriko; Nishimura, Hisao; Ito, Tomohiro; Miyata, Chie; Izumi, Keiko; Fujimaki, Hidekazu; Matsumura, Fumio

    2009-01-01

    Dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD) is known to cause bone toxicity, particularly during animal development, although its action mechanism to cause this toxicity has yet to be elucidated. Mouse pups were exposed to TCDD via dam's milk that were administered orally with 15 μg TCDD/kg b.w. on postnatal day 1. Here we report that TCDD causes up-regulation of vitamin D 1α-hydroxylase in kidney, resulting in a 2-fold increase in the active form of vitamin D, 1,25-dihydroxyvitamin D 3 , in serum. This action of TCDD is not caused by changes in parathyroid hormone, a decrease in vitamin D degrading enzyme, vitamin D 24-hydroxylase, or alterations in serum Ca 2+ concentration. Vitamin D is known to affect bone mineralization. Our data clearly show that TCDD-exposed mice exhibit a marked decrease in osteocalcin and collagen type 1 as well as alkaline phosphatase gene expression in tibia by postnatal day 21, which is accompanied with a mineralization defect in the tibia, lowered activity of osteoblastic bone formation, and an increase in fibroblastic growth factor-23, a sign of increased vitamin D effect. Despite these significant effects of TCDD on osteoblast activities, none of the markers of osteoclast activities was found to be affected. Histomorphometry confirmed that osteoblastic activity, but not bone resorption activity, was altered by TCDD. A prominent lesion commonly observed in these TCDD-treated mice was impaired bone mineralization that is characterized by an increased volume and thickness of osteoids lining both the endosteum of the cortical bone and trabeculae. Together, these data suggest that the impaired mineralization resulting from reduction of the osteoblastic activity, which is caused by TCDD-induced up-regulation of vitamin D, is responsible for its bone developmental toxicity.

  6. Aryl hydrocarbon receptor pathway activation enhances gastric cancer cell invasiveness likely through a c-Jun-dependent induction of matrix metalloproteinase-9

    Directory of Open Access Journals (Sweden)

    Song Xin

    2009-04-01

    Full Text Available Abstract Background Abberant aryl hydrocarbon receptor (AhR expression and AhR pathway activation are involved in gastric carcinogenesis. However, the relationship between AhR pathway activation and gastric cancer progression is still unclear. In present study, we used 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD, a classic and most potent ligand of AhR, to activate AhR pathway and investigated the effect of AhR pathway activation on human gastric cancer AGS cell invasion and explored the corresponding mechanism. Results To determine whether AhR pathway can be activated in AGS cells, we examined the expression of CYP1A1, a classic target gene of AhR pathway, following TCDD exposure. RT-PCR and western blot analysis showed that both CYP1A1 mRNA and protein expression were increased in a dose-dependent manner following TCDD treatment and AhR antagonist resveratrol (RSV could reverse this TCDD-induced CYP1A1 expression. To determine whether TCDD treatment of AGS cells results in an induction of MMP-9 expression, we detected MMP-9 mRNA using RT-PCR and detected MMP-9 enzymatic activity using gelatin zymography. The results showed that both MMP-9 mRNA expression and enzymatic activity were gradually increased with the concentration increase of TCDD in media and these changes could be reversed by RSV treatment in a dose-dependent manner. To examine whether AhR activation-induced MMP-9 expression and activity in AGS cells results in increased migration and invasion, we performed wound healing migration assay and transwell migration and invasion assay. After TCDD treatment, the migration distance and the migration and invasion abilities of AGS cells were increased with a dose-dependent manner. To demonstrate AhR activation-induced MMP-9 expression is mediated by c-Jun, siRNA transfection was performed to silence c-Jun mRNA in AGS cells. The results showed that MMP-9 mRNA expression and activity in untreated control AGS cells were very weak; After TCDD

  7. Unique proliferation response in odontoblastic cells derived from human skeletal muscle stem cells by cytokine-induced matrix metalloproteinase-3

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Hase, Naoko; Kawai, Rie; Yamaguchi, Hideyuki; Hiyama, Taiki [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya 464-8651, Aichi (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya 464-8651, Aichi (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan)

    2015-02-01

    A pro-inflammatory cytokine mixture (CM: interleukin (IL)-1β, tumor necrosis factor-α and interferon-γ) and IL-1β-induced matrix metalloproteinase (MMP)-3 activity have been shown to increase the proliferation of rat dental pulp cells and murine stem cell-derived odontoblast-like cells. This suggests that MMP-3 may regulate wound healing and regeneration in the odontoblast-rich dental pulp. Here, we determined whether these results can be extrapolated to human dental pulp by investigating the effects of CM-induced MMP-3 up-regulation on the proliferation and apoptosis of purified odontoblast-like cells derived from human skeletal muscle stem cells. We used siRNA to specifically reduce MMP-3 expression. We found that CM treatment increased MMP-3 mRNA and protein levels as well as MMP-3 activity. Cell proliferation was also markedly increased, with no changes in apoptosis, upon treatment with CM and following the application of exogenous MMP-3. Endogenous tissue inhibitors of metalloproteinases were constitutively expressed during all experiments and unaffected by MMP-3. Although treatment with MMP-3 siRNA suppressed cell proliferation, it also unexpectedly increased apoptosis. This siRNA-mediated increase in apoptosis could be reversed by exogenous MMP-3. These results demonstrate that cytokine-induced MMP-3 activity regulates cell proliferation and suppresses apoptosis in human odontoblast-like cells. - Highlights: • Pro-inflammatory cytokines induce MMP-3 activity in human odontoblast-like cells. • Increased MMP-3 activity can promote cell proliferation in odontoblasts. • Specific loss of MMP-3 increases apoptosis in odontoblasts. • MMP-3 has potential as a promising new target for pupal repair and regeneration.

  8. Unique proliferation response in odontoblastic cells derived from human skeletal muscle stem cells by cytokine-induced matrix metalloproteinase-3

    International Nuclear Information System (INIS)

    Ozeki, Nobuaki; Hase, Naoko; Kawai, Rie; Yamaguchi, Hideyuki; Hiyama, Taiki; Kondo, Ayami; Nakata, Kazuhiko; Mogi, Makio

    2015-01-01

    A pro-inflammatory cytokine mixture (CM: interleukin (IL)-1β, tumor necrosis factor-α and interferon-γ) and IL-1β-induced matrix metalloproteinase (MMP)-3 activity have been shown to increase the proliferation of rat dental pulp cells and murine stem cell-derived odontoblast-like cells. This suggests that MMP-3 may regulate wound healing and regeneration in the odontoblast-rich dental pulp. Here, we determined whether these results can be extrapolated to human dental pulp by investigating the effects of CM-induced MMP-3 up-regulation on the proliferation and apoptosis of purified odontoblast-like cells derived from human skeletal muscle stem cells. We used siRNA to specifically reduce MMP-3 expression. We found that CM treatment increased MMP-3 mRNA and protein levels as well as MMP-3 activity. Cell proliferation was also markedly increased, with no changes in apoptosis, upon treatment with CM and following the application of exogenous MMP-3. Endogenous tissue inhibitors of metalloproteinases were constitutively expressed during all experiments and unaffected by MMP-3. Although treatment with MMP-3 siRNA suppressed cell proliferation, it also unexpectedly increased apoptosis. This siRNA-mediated increase in apoptosis could be reversed by exogenous MMP-3. These results demonstrate that cytokine-induced MMP-3 activity regulates cell proliferation and suppresses apoptosis in human odontoblast-like cells. - Highlights: • Pro-inflammatory cytokines induce MMP-3 activity in human odontoblast-like cells. • Increased MMP-3 activity can promote cell proliferation in odontoblasts. • Specific loss of MMP-3 increases apoptosis in odontoblasts. • MMP-3 has potential as a promising new target for pupal repair and regeneration

  9. Troglitazone Induces Extracellular Matrix and Cytoskeleton Remodeling in Mouse Collecting Duct Cells

    Directory of Open Access Journals (Sweden)

    Jaime Corinaldi

    2012-01-01

    Full Text Available Peroxisome proliferator-activated receptor (PPARγ has been shown to have a protective role in the nephron through its ability to inhibit a transforming growth factor- (TGF-β mediated fibrotic response. In contrast, PPARγ was also shown to induce a mesenchymal transformation in epithelial intestinal cells. A fibrotic response in the collecting duct has only recently been established; however, the entire collecting duct has not been fully examined. Inner medullary collecting duct cells (IMCD-K2 and mouse cortical collecting duct cells (M1, representing the cortical and medullary collecting duct, were exposed to 5–10 μM troglitazone for 24 hours. Troglitazone resulted in an elongated morphology, 60% decreases in E-cadherin and β-catenin, a 35% decrease in α-catenin, and a 1.5-fold increase in fibronectin. These effects were not reversed with PPARγ antagonists or affected with PPARγ overexpression. Our results indicate that troglitazone induced a mesenchymal-like transformation in M1 and IMCD-K2 epithelial cells independently of PPARγ.

  10. Matrix rigidity induces osteolytic gene expression of metastatic breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Nazanin S Ruppender

    Full Text Available Nearly 70% of breast cancer patients with advanced disease will develop bone metastases. Once established in bone, tumor cells produce factors that cause changes in normal bone remodeling, such as parathyroid hormone-related protein (PTHrP. While enhanced expression of PTHrP is known to stimulate osteoclasts to resorb bone, the environmental factors driving tumor cells to express PTHrP in the early stages of development of metastatic bone disease are unknown. In this study, we have shown that tumor cells known to metastasize to bone respond to 2D substrates with rigidities comparable to that of the bone microenvironment by increasing expression and production of PTHrP. The cellular response is regulated by Rho-dependent actomyosin contractility mediated by TGF-ß signaling. Inhibition of Rho-associated kinase (ROCK using both pharmacological and genetic approaches decreased PTHrP expression. Furthermore, cells expressing a dominant negative form of the TGF-ß receptor did not respond to substrate rigidity, and inhibition of ROCK decreased PTHrP expression induced by exogenous TGF-ß. These observations suggest a role for the differential rigidity of the mineralized bone microenvironment in early stages of tumor-induced osteolysis, which is especially important in metastatic cancer since many cancers (such as those of the breast and lung preferentially metastasize to bone.

  11. Oxidative stress-induced apoptosis and matrix loss of chondrocytes is inhibited by eicosapentaenoic acid.

    Science.gov (United States)

    Sakata, Shuhei; Hayashi, Shinya; Fujishiro, Takaaki; Kawakita, Kohei; Kanzaki, Noriyuki; Hashimoto, Shingo; Iwasa, Kenjiro; Chinzei, Nobuaki; Kihara, Shinsuke; Haneda, Masahiko; Ueha, Takeshi; Nishiyama, Takayuki; Kuroda, Ryosuke; Kurosaka, Masahiro

    2015-03-01

    Eicosapentaenoic acid (EPA) is an antioxidant and n-3 polyunsaturated fatty acid that reduces the production of inflammatory cytokines. We evaluated the role of EPA in chondrocyte apoptosis and degeneration. Normal human chondrocytes were treated with EPA and sodium nitroprusside (SNP). Expression of metalloproteinases (MMPs) was detected by real-time polymerase chain reaction (PCR) and that of apoptosis-related proteins was detected by western blotting. Chondrocyte apoptosis was detected by flow cytometry. C57BL/6J mice were used for the detection of MMP expression by immunohistochemistry and for investigation of chondrocyte apoptosis. EPA inhibited SNP-induced chondrocyte apoptosis, caspase 3 and poly(ADP-ribose) polymerase cleavage, phosphorylation of p38 MAPK and p53, and expression of MMP3 and MMP13. Intra-articular injection of EPA prevented the progression of osteoarthritis (OA) by inhibiting MMP13 expression and chondrocyte apoptosis. EPA treatment can control oxidative stress-induced OA progression, and thus may be a new approach for OA therapy. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  12. Quantitative determination of copper in a glass matrix using double pulse laser induced breakdown and electron paramagnetic resonance spectroscopic techniques.

    Science.gov (United States)

    Khalil, Ahmed A I; Morsy, Mohamed A

    2016-07-01

    A series of lithium-lead-borate glasses of a variable copper oxide loading were quantitatively analyzed in this work using two distinct spectroscopic techniques, namely double pulse laser induced breakdown spectroscopy (DP-LIBS) and electron paramagnetic resonance (EPR). DP-LIBS results measured upon a combined nanosecond lasers irradiation running at 266nm and 1064nm pulses of a collinear configuration directed to the surface of borate glass samples with a known composition. This arrangement was employed to predict the electron's temperature (Te) and density (Ne) of the excited plasma from the recorded spectra. The intensity of elements' responses using this scheme is higher than that of single-pulse laser induced breakdown spectroscopy (SP-LIBS) setup under the same experimental conditions. On the other hand, the EPR data shows typical Cu (II) EPR-signals in the borate glass system that is networked at a distorted tetragonal Borate-arrangement. The signal intensity of the Cu (II) peak at g⊥=2.0596 has been used to quantify the Cu-content accurately in the glass matrix. Both techniques produced linear calibration curves of Cu-metals in glasses with excellent linear regression coefficient (R(2)) values. This study establishes a good correlation between DP-LIBS analysis of glass and the results obtained using EPR spectroscopy. The proposed protocols prove the great advantage of DP-LIBS system for the detection of a trace copper on the surface of glasses. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Protective effect of honokiol against LPS-induced lung injury via attenuation of matrix metalloproteinase-9 and oxidative stress

    Directory of Open Access Journals (Sweden)

    Li Hong-Bo

    2016-01-01

    Full Text Available Despite high morbidity and mortality, no effective options are available for the treatment of acute lung injury (ALI. Therefore, the present study investigated the protective effect of honokiol (HK on ALI via determination of its effect on several key biomarkers. The results of the study showed that HK significantly inhibited the infiltration of neutrophils and protein leakage induced by lipopolysaccharide (LPS (p<0.05. The pretreatment with HK considerably boosted the endogenous antioxidant defense system to counteract the oxidative stress in LPS-induced ALI by elevating the levels of superoxide dismutase (SOD, catalase (CAT and glutathione (GSH. Moreover, the activity of toxic mediators, such as myeloperoxidase (MPO, and lipid peroxidation were significantly inhibited upon treatment with HK. In order to examine the mechanism of action of HK, its effect was quantified using matrix metalloproteinase-9 (MMP-9 activity in bronchoalveolar lavage fluid (BALF by gelatin zymography. Pretreatment with HK considerably suppressed the activation of MMP-9 in a concentration-dependent manner. These findings suggest that HK protects from lung injury via inhibition of MMP-9, and by enhancing the activity of the endogenous antioxidant defense system.

  14. Microstructures induced by excimer laser surface melting of the SiC{sub p}/Al metal matrix composite

    Energy Technology Data Exchange (ETDEWEB)

    Qian, D.S., E-mail: Daishu.qian@postgrad.manchester.ac.uk; Zhong, X.L.; Yan, Y.Z.; Hashimoto, T.; Liu, Z.

    2017-08-01

    Highlights: • Microstructural analysis of the excimer laser-melted SiC{sub p}/AA2124;. • Analytical, FEM, and SPH simulation of the laser-material interaction;. • Mechanism of the formation of the laser-induced microstructure. - Abstract: Laser surface melting (LSM) was carried out on the SiC{sub p}/Al metal matrix composite (MMC) using a KrF excimer laser with a fluence of 7 J/cm{sup 2}. The re-solidification microstructure was characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) equipped with energy dispersive X-ray detector, and X-ray diffraction (XRD) analysis. It was found that a 2.5 μm thick melted layer was formed in the near-surface region, in which dissolution of the intermetallics and removal of the SiC particles occurred. The thermal and material response upon laser irradiation was simulated using three models, i.e. analytical model, finite element model (FEM) and smoothed-particle hydrodynamics (SPH) model. The effect of SiC particles on the LSM process, the mechanism of the SiC removal and the re-solidification microstructures in the melted layer were discussed. The simulation results were in good agreement with the experimental results and contributed to the generic understanding of the re-solidification microstructures induced by ns-pulsed lasers.

  15. Fucosterol inhibits matrix metalloproteinase expression and promotes type-1 procollagen production in UVB-induced HaCaT cells.

    Science.gov (United States)

    Kim, Myung-Suk; Oh, Ga-Hui; Kim, Min-Ji; Hwang, Jae-Kwan

    2013-01-01

    Ultraviolet (UV) radiation damages human skin and causes skin diseases such as epidermal hyperplasia, sunburn, inflammatory responses and photoaging. Photoaging is associated with upregulated matrix metalloproteinase (MMP) expression and downregulated collagen synthesis. Fucosterol, which is isolated from marine brown algae, has been reported to possess antioxidant and anticancer activities; however, its effects on photoaging are unknown. This study assessed the effects of fucosterol on photoaging and investigated its mechanisms of action in UV-irradiated immortalized human keratinocytes (HaCaT) by enzyme-linked immunosorbent assay, semi-quantitative reverse transcription-polymerase chain reaction, Western blot analysis and 2',7'-dichlorofluorescein diacetate assay. Our results showed that fucosterol attenuated UV-induced MMP and inflammatory cytokine expression by deactivating mitogen-activated protein kinases (MAPKs) induced by reactive oxygen species. Fucosterol also increased type-I procollagen and antioxidant enzyme expression. Taken together, fucosterol regulates the expression of MMPs and type-I procollagen in UV-irradiated HaCaT by modulating MAPK, suggesting it as a potential candidate for prevention and treatment of skin aging. © 2013 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2013 The American Society of Photobiology.

  16. Concentrations of PCBs, DDTs, and TCDD equivalents in cyprinids of the Middle Po River, Italy.

    Science.gov (United States)

    Viganò, L; Arillo, A; Aurigi, S; Corsi, I; Focardi, S

    2000-02-01

    The concentrations of non-ortho-, mono-ortho-, di-ortho-substituted polychlorinated biphenyls (PCBs) and DDTs (pp'-DDT and pp'-DDE) were measured in fish and bed sediments of the Po River. Three species of cyprinids, nase (Chondrostoma söetta), chub (Leuciscus cephalus), and barbel (Barbus plebejus), were captured in the major Italian river, upstream and downstream from the confluence of the Lambro River. The two carnivorous species, chub and barbel, were found to be the most contaminated, showing muscle tissue concentrations up to eightfold higher than the corresponding upstream fish. DDT concentrations were parallel to PCB changes although at lower values. Despite the increased contamination caused by the input from the Lambro tributary, when fish PCB loads are converted to 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents using piscine toxic equivalency factors (TEFs), no specific hazard can be associated to the limited toxic potentials of PCBs. Although these results seem to minimise the risk for the fish community of the Po River, the presence of other organochlorines and halogenated hydrocarbons is very probable in the downstream area, and a more exhaustive hazard assessment, based on further studies, should be undertaken.

  17. A Wnt/β-catenin negative feedback loop inhibits interleukin-1-induced matrix metalloproteinase expression in human articular chondrocytes.

    Science.gov (United States)

    Ma, Bin; van Blitterswijk, Clemens A; Karperien, Marcel

    2012-08-01

    The results of recent animal studies suggest that activation of Wnt/β-catenin signaling in articular chondrocytes might be a driving factor in the pathogenesis of osteoarthritis (OA) by stimulating, for instance, the expression of matrix metalloproteinases (MMPs). The aim of this study was to investigate the role of Wnt/β-catenin signaling in interleukin-1β (IL-1β)-induced MMP expression in human chondrocytes. Primary cultures of human, murine, and bovine articular chondrocytes as well as human mesenchymal stem cells and mouse embryonic fibroblasts were used in the experiments. Multiple strategies for the activation and inhibition of signaling pathways were utilized. Reporter assays and coimmunoprecipitation were performed to study the interaction between β-catenin and NF-κB. In contrast to the role of Wnt/β-catenin in animal chondrocytes, in human chondrocytes it was a potent inhibitor of MMP-1, MMP-3, and MMP-13 expression and generic MMP activity both in basal conditions and after IL-1β stimulation. This effect was independent of the T cell factor/lymphoid enhancer factor family of transcription factors but rather was attributable to an inhibitory protein-protein interaction between β-catenin and NF-κB. IL-1β indirectly activated β-catenin signaling by inducing canonical Wnt-7B expression and by inhibiting the expression of canonical Wnt antagonists. Wnt/β-catenin signaling in human chondrocytes had an unexpected anticatabolic role by counteracting NF-κB-mediated MMP expression induced by IL-1β in a negative feedback loop. Copyright © 2012 by the American College of Rheumatology.

  18. The gelatinous extracellular matrix facilitates transport studies in kelp: visualization of pressure-induced flow reversal across sieve plates.

    Science.gov (United States)

    Knoblauch, Jan; Peters, Winfried S; Knoblauch, Michael

    2016-04-01

    In vascular plants, important questions regarding phloem function remain unanswered due to problems with invasive experimental procedures in this highly sensitive tissue. Certain brown algae (kelps; Laminariales) also possess sieve tubes for photoassimilate transport, but these are embedded in large volumes of a gelatinous extracellular matrix which isolates them from neighbouring cells. Therefore, we hypothesized that kelp sieve tubes might tolerate invasive experimentation better than their analogues in higher plants, and sought to establish Nereocystis luetkeana as an experimental system. The predominant localization of cellulose and the gelatinous extracellular matrix in N. luetkeana was verified using specific fluorescent markers and confocal laser scanning microscopy. Sieve tubes in intact specimens were loaded with fluorescent dyes, either passively (carboxyfluorescein diacetate; CFDA) or by microinjection (rhodamine B), and the movement of the dyes was monitored by fluorescence microscopy. Application of CFDA demonstrated source to sink bulk flow in N. luetkeana sieve tubes, and revealed the complexity of sieve tube structure, with branches, junctions and lateral connections. Microinjection into sieve elements proved comparatively easy. Pulsed rhodamine B injection enabled the determination of flow velocity in individual sieve elements, and the direct visualization of pressure-induced reversals of flow direction across sieve plates. The reversal of flow direction across sieve plates by pressurizing the downstream sieve element conclusively demonstrates that a critical requirement of the Münch theory is satisfied in kelp; no such evidence exists for tracheophytes. Because of the high tolerance of its sieve elements to experimental manipulation, N. luetkeana is a promising alternative to vascular plants for studying the fluid mechanics of sieve tube networks. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company

  19. Albumin induces upregulation of matrix metalloproteinase-9 in astrocytes via MAPK and reactive oxygen species-dependent pathways

    Directory of Open Access Journals (Sweden)

    Ranaivo Hantamalala

    2012-04-01

    Full Text Available Abstract Background Astrocytes are an integral component of the blood–brain barrier (BBB which may be compromised by ischemic or traumatic brain injury. In response to trauma, astrocytes increase expression of the endopeptidase matrix metalloproteinase (MMP-9. Compromise of the BBB leads to the infiltration of fluid and blood-derived proteins including albumin into the brain parenchyma. Albumin has been previously shown to activate astrocytes and induce the production of inflammatory mediators. The effect of albumin on MMP-9 activation in astrocytes is not known. We investigated the molecular mechanisms underlying the production of MMP-9 by albumin in astrocytes. Methods Primary enriched astrocyte cultures were used to investigate the effects of exposure to albumin on the release of MMP-9. MMP-9 expression was analyzed by zymography. The involvement of mitogen-activated protein kinase (MAPK, reactive oxygen species (ROS and the TGF-β receptor-dependent pathways were investigated using pharmacological inhibitors. The production of ROS was observed by dichlorodihydrofluorescein diacetate fluorescence. The level of the MMP-9 inhibitor tissue inhibitor of metalloproteinase (TIMP-1 produced by astrocytes was measured by ELISA. Results We found that albumin induces a time-dependent release of MMP-9 via the activation of p38 MAPK and extracellular signal regulated kinase, but not Jun kinase. Albumin-induced MMP-9 production also involves ROS production upstream of the MAPK pathways. However, albumin-induced increase in MMP-9 is independent of the TGF-β receptor, previously described as a receptor for albumin. Albumin also induces an increase in TIMP-1 via an undetermined mechanism. Conclusions These results link albumin (acting through ROS and the p38 MAPK to the activation of MMP-9 in astrocytes. Numerous studies identify a role for MMP-9 in the mechanisms of compromise of the BBB, epileptogenesis, or synaptic remodeling after ischemia or

  20. 1α,25-Dihydroxycholecalciferol (Vitamin D3 Induces NO-Dependent Endothelial Cell Proliferation and Migration in a Three-Dimensional Matrix

    Directory of Open Access Journals (Sweden)

    Claudio Molinari

    2013-06-01

    Full Text Available Background/Aims: The 1α,25-dihydroxycholecalciferol (Vit. D induces eNOS dependent nitric oxide (NO production in human umbilical vein endothelial cells (HUVEC. To our knowledge, there are no reports directly relating Vit. D induced NO production to proliferation and/or migration in endothelial cells (EC. The aim of this study was to evaluate whether Vit. D addition to porcine EC could affect their proliferation and/or migration in a three-dimensional matrix via NO production. Materials and Methods: Porcine aortic endothelial cells (PAE were used to evaluate Vit. D effects on cell proliferation and migration in a three-dimensional matrix. Results: Vit. D induced NO production in PAE cells. Moreover, it induced a significant increase in cellular proliferation and migration in a three-dimensional matrix. These effects were NO dependent, as inhibiting eNOS activity by L-NAME PAE migration was abrogated. This effect was strictly related to MMP-2 expression and apparently dependent on Vit. D and NO production. Conclusions: Vit. D can promote both endothelial cells proliferation and migration in a three-dimensional matrix via NO-dependent mechanisms. These findings cast new light on the role of Vit. D in the angiogenic process, suggesting new applications for Vit. D in such fields as tissue repair and wound healing.

  1. Hydrogen isotope detection in metal matrix using double-pulse laser-induced breakdown-spectroscopy

    Science.gov (United States)

    Fantoni, Roberta; Almaviva, Salvatore; Caneve, Luisa; Colao, Francesco; Maddaluno, Giorgio; Gasior, Pawel; Kubkowska, Monika

    2017-03-01

    The amount of hydrogen isotopes retained in plasma facing components (PFCs) and the determination of their surface layer composition are among the most critical issues for the next generation fusion device, ITER, under construction in Cadarache (France). Laser Induced Breakdown Spectroscopy (LIBS) is currently under evaluation as a technique suitable for quantitative, in situ, non-invasive measurements of these quantities. In order to detect traces of contaminant in metallic samples and improve its limit of detection (LOD), the Double Pulse LIBS (DP-LIBS) variant can be used instead of the standard Single Pulse LIBS (SP-LIBS), as it has been proven by several authors that DP-LIBS can considerably raise the analytical performances of the technique. In this work Mo samples coated with a 1.5-1.8 μm thick W-Al mixed layer, contaminated with co-deposited deuterium (D) were measured by SP- and DP-LIBS under vacuum (p 5 × 10- 5 mbar), with an experimental set-up simulating conditions that can be found in a real fusion device between plasma discharges. A partial Calibration Free procedure (pCF) was applied to the LIBS data in order to retrieve the relative concentration of W and Al in the mixed layer. The amount of deuterium was then inferred by using tungsten as internal standard, accounting for the intensity ratio between the Dα line and nearby W I lines. The results are in satisfactory agreement with those obtained from preliminary Ion Beam Analysis measurements performed immediately after the specimen's realization.

  2. Using cell-substrate impedance and live cell imaging to measure real-time changes in cellular adhesion and de-adhesion induced by matrix modification.

    Science.gov (United States)

    Rees, Martin D; Thomas, Shane R

    2015-02-19

    Cell-matrix adhesion plays a key role in controlling cell morphology and signaling. Stimuli that disrupt cell-matrix adhesion (e.g., myeloperoxidase and other matrix-modifying oxidants/enzymes released during inflammation) are implicated in triggering pathological changes in cellular function, phenotype and viability in a number of diseases. Here, we describe how cell-substrate impedance and live cell imaging approaches can be readily employed to accurately quantify real-time changes in cell adhesion and de-adhesion induced by matrix modification (using endothelial cells and myeloperoxidase as a pathophysiological matrix-modifying stimulus) with high temporal resolution and in a non-invasive manner. The xCELLigence cell-substrate impedance system continuously quantifies the area of cell-matrix adhesion by measuring the electrical impedance at the cell-substrate interface in cells grown on gold microelectrode arrays. Image analysis of time-lapse differential interference contrast movies quantifies changes in the projected area of individual cells over time, representing changes in the area of cell-matrix contact. Both techniques accurately quantify rapid changes to cellular adhesion and de-adhesion processes. Cell-substrate impedance on microelectrode biosensor arrays provides a platform for robust, high-throughput measurements. Live cell imaging analyses provide additional detail regarding the nature and dynamics of the morphological changes quantified by cell-substrate impedance measurements. These complementary approaches provide valuable new insights into how myeloperoxidase-catalyzed oxidative modification of subcellular extracellular matrix components triggers rapid changes in cell adhesion, morphology and signaling in endothelial cells. These approaches are also applicable for studying cellular adhesion dynamics in response to other matrix-modifying stimuli and in related adherent cells (e.g., epithelial cells).

  3. HIV gp120 binds to mannose receptor on vaginal epithelial cells and induces production of matrix metalloproteinases.

    Directory of Open Access Journals (Sweden)

    Sashaina E Fanibunda

    Full Text Available BACKGROUND: During sexual transmission of HIV in women, the virus breaches the multi-layered CD4 negative stratified squamous epithelial barrier of the vagina, to infect the sub-epithelial CD4 positive immune cells. However the mechanisms by which HIV gains entry into the sub-epithelial zone is hitherto unknown. We have previously reported human mannose receptor (hMR as a CD4 independent receptor playing a role in HIV transmission on human spermatozoa. The current study was undertaken to investigate the expression of hMR in vaginal epithelial cells, its HIV gp120 binding potential, affinity constants and the induction of matrix metalloproteinases (MMPs downstream of HIV gp120 binding to hMR. PRINCIPAL FINDINGS: Human vaginal epithelial cells and the immortalized vaginal epithelial cell line Vk2/E6E7 were used in this study. hMR mRNA and protein were expressed in vaginal epithelial cells and cell line, with a molecular weight of 155 kDa. HIV gp120 bound to vaginal proteins with high affinity, (Kd = 1.2±0.2 nM for vaginal cells, 1.4±0.2 nM for cell line and the hMR antagonist mannan dose dependently inhibited this binding. Both HIV gp120 binding and hMR exhibited identical patterns of localization in the epithelial cells by immunofluorescence. HIV gp120 bound to immunopurified hMR and affinity constants were 2.9±0.4 nM and 3.2±0.6 nM for vaginal cells and Vk2/E6E7 cell line respectively. HIV gp120 induced an increase in MMP-9 mRNA expression and activity by zymography, which could be inhibited by an anti-hMR antibody. CONCLUSION: hMR expressed by vaginal epithelial cells has high affinity for HIV gp120 and this binding induces production of MMPs. We propose that the induction of MMPs in response to HIV gp120 may lead to degradation of tight junction proteins and the extracellular matrix proteins in the vaginal epithelium and basement membrane, leading to weakening of the epithelial barrier; thereby facilitating transport of HIV across the

  4. Role of the cyclooxygenase 2-thromboxane pathway in 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced decrease in mesencephalic vein blood flow in the zebrafish embryo

    International Nuclear Information System (INIS)

    Teraoka, Hiroki; Kubota, Akira; Dong, Wu; Kawai, Yusuke; Yamazaki, Koji; Mori, Chisato; Harada, Yoshiteru; Peterson, Richard E.; Hiraga, Takeo

    2009-01-01

    Previously, we reported that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) evoked developmental toxicity required activation of aryl hydrocarbon receptor type 2 (AHR2), using zebrafish embryos. However, the downstream molecular targets of AHR2 activation are largely unknown and are the focus of the present investigation. TCDD induces cyclooxygenase 2 (COX2), a rate-limiting enzyme for prostaglandin synthesis in certain cells. In the present study, we investigated the role of the COX2-thromboxane pathway in causing a specific endpoint of TCDD developmental toxicity in the zebrafish embryo, namely, a decrease in regional blood flow in the dorsal midbrain. It was found that the TCDD-induced reduction in mesencephalic vein blood flow was markedly inhibited by selective COX2 inhibitors, NS-398 and SC-236, and by a general COX inhibitor, indomethacin, but not by a selective COX1 inhibitor, SC-560. Gene knock-down of COX2 by two different types of morpholino antisense oligonucleotides, but not by their negative homologs, also protected the zebrafish embryos from mesencephalic vein circulation failure caused by TCDD. This inhibitory effect of TCDD on regional blood flow in the dorsal midbrain was also blocked by selective antagonists of the thromboxane receptor (TP). Treatment of control zebrafish embryos with a TP agonist also caused a reduction in mesencephalic vein blood flow and it too was blocked by a TP antagonist, without any effect on trunk circulation. Finally, gene knock-down of thromboxane A synthase 1 (TBXS) with morpholinos but not by the morpholinos' negative homologs provided significant protection against TCDD-induced mesencephalic circulation failure. Taken together, these results point to a role of the prostanoid synthesis pathway via COX2-TBXS-TP in the local circulation failure induced by TCDD in the dorsal midbrain of the zebrafish embryo

  5. 4-Methoxyestradiol-induced oxidative injuries in human lung epithelial cells

    International Nuclear Information System (INIS)

    Cheng Yahsin; Chang, Louis W.; Cheng Lichuan; Tsai, M.-H.; Lin Pinpin

    2007-01-01

    Epidemiological studies indicated that people exposed to dioxins were prone to the development of lung diseases including lung cancer. Animal studies demonstrated that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increased liver tumors and promoted lung metaplasia in females. Metabolic changes in 17β-estradiol (E 2 ) resulted from an interaction between TCDD and E 2 could be associated with gender difference. Previously, we reported that methoxylestradiols (MeOE 2 ), especially 4-MeOE 2 , accumulated in human lung cells (BEAS-2B) co-treated with TCDD and E 2 . In the present study, we demonstrate unique accumulation of 4-MeOE 2 , as a result of TCDD/E 2 interaction and revealed its bioactivity in human lung epithelial cell line (H1355). 4-Methoxyestradiol treatment significantly decreased cell growth and increased mitotic index. Elevation of ROS and SOD activity, with a concomitant decrease in the intracellular GSH/GSSG ratio, was also detected in 4-MeOE 2 -treated cells. Quantitative comet assay showed increased oxidative DNA damage in the 4-MeOE 2 -treated H1355 cells, which could be significantly reduced by the anti-oxidant N-acetylcysteine (NAC). However, inhibition of cell growth and increase in mitotic arrest induced by 4-MeOE 2 were unaffected by NAC. We concluded that 4-MeOE 2 accumulation resulting from TCDD and E 2 interaction would contribute to the higher vulnerability on lung pathogenesis in females when exposed to TCDD

  6. An extract of Crataegus pinnatifida fruit attenuates airway inflammation by modulation of matrix metalloproteinase-9 in ovalbumin induced asthma.

    Directory of Open Access Journals (Sweden)

    In Sik Shin

    Full Text Available BACKGROUND: Crataegus pinnatifida (Chinese hawthorn has long been used as a herbal medicine in Asia and Europe. It has been used for the treatment of various cardiovascular diseases such as myocardial weakness, tachycardia, hypertension and arteriosclerosis. In this study, we investigated the anti-inflammatory effects of Crataegus pinnatifida ethanolic extracts (CPEE on Th2-type cytokines, eosinophil infiltration, expression of matrix metalloproteinase (MMP-9, and other factors, using an ovalbumin (OVA-induced murine asthma model. METHODS/PRINCIPAL FINDING: Airways of OVA-sensitized mice exposed to OVA challenge developed eosinophilia, mucus hypersecretion and increased cytokine levels. CPEE was applied 1 h prior to OVA challenge. Mice were administered CPEE orally at doses of 100 and 200 mg/kg once daily on days 18-23. Bronchoalveolar lavage fluid (BALF was collected 48 h after the final OVA challenge. Levels of interleukin (IL-4 and IL-5 in BALF were measured using enzyme-linked immunosorbent (ELISA assays. Lung tissue sections 4 µm in thickness were stained with Mayer's hematoxylin and eosin for assessment of cell infiltration and mucus production with PAS staining, in conjunction with ELISA, and Western blot analyses for the expression of MMP-9, intercellular adhesion molecule (ICAM-1 and vascular cell adhesion molecule (VCAM-1 protein expression. CPEE significantly decreased the Th2 cytokines including IL-4 and IL-5 levels, reduced the number of inflammatory cells in BALF and airway hyperresponsiveness, suppressed the infiltration of eosinophil-rich inflammatory cells and mucus hypersecretion and reduced the expression of ICAM-1, VCAM-1 and MMP-9 and the activity of MMP-9 in lung tissue of OVA-challenged mice. CONCLUSIONS: These results showed that CPEE can protect against allergic airway inflammation and can act as an MMP-9 modulator to induce a reduction in ICAM-1 and VCAM-1 expression. In conclusion, we strongly suggest the feasibility

  7. Resveratrol suppresses TPA-induced matrix metalloproteinase-9 expression through the inhibition of MAPK pathways in oral cancer cells.

    Science.gov (United States)

    Lin, Feng-Yan; Hsieh, Yi-Hsien; Yang, Shun-Fa; Chen, Chang-Tai; Tang, Chih-Hsin; Chou, Ming-Yung; Chuang, Yi-Ting; Lin, Chiao-Wen; Chen, Mu-Kuan

    2015-10-01

    Naturally occurring agents, such as resveratrol, have been determined to benefit health. Numerous studies have demonstrated that resveratrol has antioxidative, cardioprotective, and neuroprotective properties. However, the effect of resveratrol exerts on the metastasis of oral cancer cells remains unclear. In this study, we investigated the effect the anti-invasive activity of resveratrol on a human oral cancer cell line (SCC-9) in vitro and the underlying mechanisms. Cell viability was examined by MTT assay, whereas cell motility was measured by migration and wound-healing assays. Zymography, reverse-transcriptase polymerase chain reaction (PCR), and promoter assays confirmed the inhibitory effects of resveratrol on matrix metalloproteinase-9 (MMP-9) expression in oral cancer cells. We established that various concentrations (0-100 μM) of resveratrol inhibited the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced migration capacities of SCC-9 cells and caused no cytotoxic effects. Zymography and Western blot analyses suggested that resveratrol inhibited TPA-induced MMP-9 gelatinolytic activity and protein expression. In addition, the results indicated that resveratrol inhibited the phosphorylation of c-Jun N-terminal kinase (JNK)1/2 and extracellular-signal-regulated kinase (ERK)1/2 involved in downregulating protein expression and the transcription of MMP-9. In summary, resveratrol inhibited MMP-9 expression and oral cancer cell metastasis by downregulating JNK1/2 and ERK1/2 signals pathways and, thus, exerts beneficial effects in chemoprevention. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. 37% Phosphoric Acid Induced Stronger Matrix Metalloproteinase-8 Expression of the Dental Pulp than 19% Ethylene Diamine Tetraacetic Acid

    Directory of Open Access Journals (Sweden)

    Nadie Fatimatuzzahro

    2014-11-01

    Full Text Available Etching agents such as ethylene diamine tetraacetic acid (EDTA and phosphoric acid which are widely used in adhesive restoration system aimed to increase for retention of restorative materials, may act a chemical irritant that induce inflammation of dental pulp. Inflammation is a body response against irritant and infectious agents. Matrix metalloproteinase-8, the major collagenolytic enzyme, degrades collagen type 1. This enzyme is expressed in low level in normal condition, however, the expression will increase during inflammation. The purpose of the present research was to study the effect of 19% EDTA and 37% phosphoric acid application as an etching agents on the MMP-8 expression of dental pulp. Forty-five male Sprague Dawley rats were divided into 3 groups. Cavity preparation was made on the occlusal surface of maxillary first molar using a round diamond bur. 19% EDTA, 37% phosphoric acid, and distilled water were applied on the surface of the cavity of the teeth in group I, II, and III subsequently. The cavity then filed by glass ionomer cements. The rats were sacrified at 1, 3, 5, 7, and 14 days after the treatment (n=3 for each day. The specimens were then processed histologically. Immunohistochemical (IHC analysis was performed using rabbit anti rat MMP-8 polyclonal antibody to examine MMP-8 expression and HE (Hematoxylen Eosin staining to observe the number of macrophages. The results showed 37% phosphoric acid application induced stronger expression of MMP-8 and higher number of macrophages than 19% EDTA. The strongest expression of MMP-8 seems on 5 days after the treatment where the highest number of macrophages were also found.

  9. Nicotinic Acetylcholine Receptor Mediates Nicotine-Induced Actin Cytoskeletal Remodeling and Extracellular Matrix Degradation by Vascular Smooth Muscle Cells

    Science.gov (United States)

    Gu, Zhizhan; Fonseca, Vera; Hai, Chi-Ming

    2012-01-01

    Cigarette smoking is a significant risk factor for atherosclerosis, which involves the invasion of vascular smooth muscle cells (VSMCs) from the media to intima. A hallmark of many invasive cells is actin cytoskeletal remodeling in the form of podosomes, accompanied by extracellular matrix (ECM) degradation. A7r5 VSMCs form podosomes in response to PKC activation. In this study, we found that cigarette smoke extract, nicotine, and the cholinergic agonist, carbachol, were similarly effective in inducing the formation of podosome rosettes in A7r5 VSMCs. α-Bungarotoxin and atropine experiments confirmed the involvement of nicotinic acetylcholine receptors (nAChRs). Western blotting and immunofluorescence experiments revealed the aggregation of nAChRs at podosome rosettes. Cycloheximide experiments and media exchange experiments suggested that autocrine factor(s) and intracellular phenotypic modulation are putative mechanisms. In situ zymography experiments indicated that, in response to PKC activation, nicotine-treated cells degraded ECM near podosome rosettes, and possibly endocytose ECM fragments to intracellular compartments. Invasion assay of human aortic smooth muscle cells indicated that nicotine and PKC activation individually and synergistically enhanced cell invasion through ECM. Results from this study suggest that nicotine enhances the ability of VSMCs to degrade and invade ECM. nAChR activation, actin cytoskeletal remodeling and phenotypic modulation are possible mechanisms. PMID:22940282

  10. Sports Activity After Reconstruction of Osteochondral Lesions of the Talus With Autologous Spongiosa Grafts and Autologous Matrix-Induced Chondrogenesis.

    Science.gov (United States)

    Wiewiorski, Martin; Werner, Lorenzo; Paul, Jochen; Anderson, Andrew E; Barg, Alexej; Valderrabano, Victor

    2016-10-01

    For the treatment of osteochondral lesions of the talus (OCLTs), autologous matrix-induced chondrogenesis (AMIC) is a safe 1-step procedure with good clinical and radiological results. However, data regarding postoperative sports activity after AMIC are limited. To identify significant factors influencing the rate of postoperative sports and recreational activities. Case series; Level of evidence, 4. The sports and recreational activities of 60 patients (mean age, 34.9 ± 11.5 years) undergoing the AMIC procedure were retrospectively analyzed at a mean of 46.9 ± 17.8 months (range, 24.5-87.0 months) postoperatively. The visual analog scale (VAS) for pain score, Tegner activity scale score, activity rating scale (ARS) score, and satisfaction with surgery outcomes were assessed. Corrective calcaneal osteotomy was performed in 38 of 60 (63.3%) patients. Ligament repair was performed in 41 of 60 (68.3%) patients. The mean VAS score improved significantly from 6.9 ± 1.6 points (range, 5-10 points) preoperatively to 2.3 ± 1.9 points (range, 0-6 points) at latest follow-up (P sports activity before the onset of symptoms became significantly lower at the time of surgery (from 95.0% to 53.3%; P sports frequency and the duration of sports activity was found postoperatively. Patients undergoing AMIC repair of an OCLT participate at a similar low postoperative sports and recreational activity level compared with the preoperative level. © 2016 The Author(s).

  11. Matrix metalloproteinases regulate the formation of dendritic spine head protrusions during chemically induced long-term potentiation.

    Directory of Open Access Journals (Sweden)

    Zsuzsanna Szepesi

    Full Text Available Dendritic spines are are small membranous protrusions that extend from neuronal dendrites and harbor the majority of excitatory synapses. Increasing evidence has shown that matrix metalloproteinases (MMPs, a family of extracellularly acting and Zn(2+-dependent endopeptidases, are able to rapidly modulate dendritic spine morphology. Spine head protrusions (SHPs are filopodia-like processes that extend from the dendritic spine head, representing a form of postsynaptic structural remodeling in response to altered neuronal activity. Herein, we show that chemically induced long-term potentiation (cLTP in dissociated hippocampal cultures upregulates MMP-9 activity that controls the formation of SHPs. Blocking of MMPs activity or microtubule dynamics abolishes the emergence of SHPs. In addition, autoactive recombinant MMP-9, promotes the formation of SHPs in organotypic hippocampal slices. Furthermore, spines with SHPs gained postsynaptic α-amino-3-hydroxyl-5-methyl-4-isoxazole propionic acid (AMPA receptors upon cLTP and the synaptic delivery of AMPA receptors was controlled by MMPs. The present results strongly imply that MMP-9 is functionally involved in the formation of SHPs and the control of postsynaptic receptor distribution upon cLTP.

  12. Altered expression of matrix metalloproteinases and tight junction proteins in rats following PEMF-induced BBB permeability change.

    Science.gov (United States)

    Zhang, Ya Mei; Zhou, Yan; Qiu, Lian Bo; Ding, Gui Rong; Pang, Xiao Feng

    2012-04-01

    To investigate the expression of occludin, ZO-1, MMP-2, and MMP-9 in cerebral microvasculature following Pulse Electromagnetic Field (PEMF) induced BBB permeability change. Sprague-Dawley rats were randomized into PEMF and sham exposed groups (n = 8). After exposure to PEMF at 0.5, 1, 3, 6, and 12 h, BBB permeability was measured by Evans-Blue extravasation. The expression of occludin, ZO-1, MMP-2, and MMP-9 were detected by real-time quantitative reverse transcriptase PCR and western blotting. MMP-2 and MMP-9 activity were detected by EnzChek gelatinase assay. Compared with the sham group, PEMF exposure led to increased permeability of the BBB to EB, which was prolonged after exposure. BBB permeability became progressively more severe, and recovered at 6 h. The gene and protein expression of occludin and ZO-1 were significantly decreased, while MMP-2 and MMP-9 expression were significantly increased after exposure to PEMF. All levels of expression recovered 12 h following PEMF. Changes to BBB permeability were related to the alteration expression of tight junction proteins and matrix metalloproteinase after exposure to PEMF.

  13. Early applications of the R-matrix SAMMY code for charged-particle induced reactions and related covariances

    Science.gov (United States)

    Pigni, Marco T.; Gauld, Ian C.; Croft, Stephen

    2017-09-01

    The SAMMY code system is mainly used in nuclear data evaluations for incident neutrons in the resolved resonance region (RRR), however, built-in capabilities also allow the code to describe the resonance structure produced by other incident particles, including charged particles. (α,n) data provide fundamental information that underpins nuclear modeling and simulation software, such as ORIGEN and SOURCES4C, used for the analysis of neutron emission and definition of source emission processes. The goal of this work is to carry out evaluations of charged-particle-induced reaction cross sections in the RRR. The SAMMY code was recently used in this regard to generate a Reich-Moore parameterization of the available 17,18O(α,n) experimental cross sections in order to estimate the uncertainty in the neutron generation rates for uranium oxide fuel types. This paper provides a brief description of the SAMMY evaluation procedure for the treatment of 17,18O(α,n) reaction cross sections. The results are used to generate neutron source rates for a plutonium oxide matrix.

  14. Bacterial nanocellulose-IKVAV hydrogel matrix modulates melanoma tumor cell adhesion and proliferation and induces vasculogenic mimicry in vitro.

    Science.gov (United States)

    Reis, Emily M Dos; Berti, Fernanda V; Colla, Guilherme; Porto, Luismar M

    2017-12-05

    Vasculogenic mimicry process has generated great interest over the past decade. So far, however, there have been only a few matrices available that allow us to study that process in vitro. Here, we have developed an innovative hydrogel platform with defined composition that mimics the structural architecture and biological functions of the extracellular matrix for vasculogenic mimicry of human melanoma cells (SK-MEL-28). We chemically immobilized IKVAV peptide on bacterial nanocellulose (BNC) fibers. BNC-IKVAV hydrogel was found to improve the adhesion and proliferation of SK-MEL-28 cells on the top and bottom surfaces. Particularly, the bottom surface of BNC-IKVAV induced SK-MEL-28 cells to organize themselves as well-established networks related to the vasculogenic mimicry process. Finally, our results showed that not only BNC-IKVAV but also BNC hydrogels can potentially be used as a three-dimensional platform that allows the screening of antitumor drugs. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

  15. Comparison of the in vitro effects of TCDD, PCB 126 and PCB 153 on thyroid-restricted gene expression and thyroid hormone secretion by the chicken thyroid gland.

    Science.gov (United States)

    Katarzyńska, Dorota; Hrabia, Anna; Kowalik, Kinga; Sechman, Andrzej

    2015-03-01

    The aim of this study was to compare the in vitro effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3',4,4',5-pentachlorobiphenyl (PCB 126; a coplanar PCB congener) and 2,2'4,4',5,5'-hexachlorobiphenyl (PCB153; non-coplanar PCB) on mRNA expression of thyroid-restricted genes, i.e. sodium iodide symporter (NIS), thyroid peroxidase (TPO) and thyroglobulin (TG), and thyroid hormone secretion from the thyroid gland of the laying chicken. Relative expression levels of NIS, TG and TPO genes and thyroxine (T4) and triiodothyronine (T3) secretion from the thyroidal explants were quantified by the real-time qPCR and RIA methods, respectively. In comparison with the control group, TCDD and PCB 126 significantly increased mRNA expression of TPO and TG genes. TCDD did not affect NIS mRNA levels, but PCB 126 decreased its expression. No effect of PCB 153 on the expression of these genes was observed. TCDD and PCB 126 significantly decreased T4 and T3 secretion. There was no significant effect of PCB 153 on these hormone secretions. In conclusion, the results obtained show that in comparison with non-coplanar PCB 153, TCDD and coplanar PCB 126 can directly affect thyroid hormone synthesis and secretion, and in consequence, they may disrupt the endocrine function of the thyroid gland of the laying chicken. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Identification of Serine Conformers by Matrix-Isolation IR Spectroscopy Aided by Near-Infrared Laser Induced Conformational Change, 2D Correlation Analysis, and Quantum Mechanical Anharmonic Computations

    Science.gov (United States)

    Najbauer, Eszter E.; Bazsó, Gábor; Apóstolo, Rui; Fausto, Rui; Biczysko, Malgorzata; Barone, Vincenzo; Tarczay, György

    2018-01-01

    The conformers of α-serine were investigated by matrix-isolation IR spectroscopy combined with NIR laser irradiation. This method, aided by 2D correlation analysis, enabled unambiguously grouping the spectral lines to individual conformers. On the basis of comparison of at least nine experimentally observed vibrational transitions of each conformer with empirically scaled (SQM) and anharmonic (GVPT2) computed IR spectra, 6 conformers were identified. In addition, the presence of at least one more conformer in Ar matrix was proved, and a short-lived conformer with a half-live of (3.7±0.5)·103 s in N2 matrix was generated by NIR irradiation. The analysis of the NIR laser induced conversions revealed that the excitation of the stretching overtone of both the side-chain and the carboxylic OH groups can effectively promote conformational changes, but remarkably different paths were observed for the two kinds of excitations. PMID:26201050

  17. Matrix metalloproteinase 7 restrains Helicobacter pylori-induced gastric inflammation and premalignant lesions in the stomach by altering macrophage polarization.

    Science.gov (United States)

    Krakowiak, M S; Noto, J M; Piazuelo, M B; Hardbower, D M; Romero-Gallo, J; Delgado, A; Chaturvedi, R; Correa, P; Wilson, K T; Peek, R M

    2015-04-02

    Helicobacter pylori is the strongest risk factor for the development of gastric cancer. Although the specific mechanisms by which this pathogen induces carcinogenesis have not been fully elucidated, high-expression interleukin (IL)-1β alleles are associated with increased gastric cancer risk among H. pylori-infected persons. In addition, loss of matrix metalloproteinase 7 (MMP7) increases mucosal inflammation in mouse models of epithelial injury, and we have shown that gastric inflammation is increased in H. pylori-infected MMP7(-/-) C57BL/6 mice. In this report, we define mechanisms that underpin such responses and extend these results into a genetic model of MMP7 deficiency and gastric cancer. Wild-type (WT) or MMP7(-/-) C57BL/6 mice were challenged with broth alone as an uninfected control or the H. pylori strain PMSS1. All H. pylori-challenged mice were successfully colonized. As expected, H. pylori-infected MMP7(-/-) C57BL/6 mice exhibited a significant increase in gastric inflammation compared with uninfected or infected WT C57BL/6 animals. Loss of MMP7 resulted in M1 macrophage polarization within H. pylori-infected stomachs, as assessed by Luminex technology and immunohistochemistry, and macrophages isolated from infected MMP7-deficient mice expressed significantly higher levels of the M1 macrophage marker IL-1β compared with macrophages isolated from WT mice. To extend these findings into a model of gastric cancer, hypergastrinemic WT INS-GAS or MMP7(-/-) INS-GAS mice were challenged with H. pylori strain PMSS1. Consistent with findings in the C57BL/6 model, H. pylori-infected MMP7-deficient INS-GAS mice exhibited a significant increase in gastric inflammation compared with either uninfected or infected WT INS-GAS mice. In addition, the incidence of gastric hyperplasia and dysplasia was significantly increased in H. pylori-infected MMP7(-/-) INS-GAS mice compared with infected WT INS-GAS mice, and loss of MMP7 promoted M1 macrophage polarization. These

  18. In vivo imaging of matrix metalloprotease 12 and matrix metalloprotease 13 activities in the mouse model of collagen-induced arthritis

    DEFF Research Database (Denmark)

    Lim, Ngee Han; Meinjohanns, Ernst; Bou-Gharios, George

    2014-01-01

    inhibitor GM6001 and specific synthetic inhibitors of MMP-12 and MMP-13. The probes were used to follow these enzyme activities in the collagen-induced arthritis (CIA) model in vivo. Results. The MMP-12- and MMP-13-activity probes (MMP12ap and MMP13ap, respectively) discriminated between the two enzymatic...... activities. The in vivo activation of these probes was inhibited by GM6001 and by their respective specific inhibitors. In the CIA model, MMP12ap activation peaked 5 days after disease onset and showed strong correlation with disease severity during this time (r = 0.85; p...

  19. Release of tensile strain on engineered human tendon tissue disturbs cell adhesions, changes matrix architecture, and induces an inflammatory phenotype

    DEFF Research Database (Denmark)

    Bayer, Monika L; Schjerling, Peter; Herchenhan, Andreas

    2014-01-01

    Mechanical loading of tendon cells results in an upregulation of mechanotransduction signaling pathways, cell-matrix adhesion and collagen synthesis, but whether unloading removes these responses is unclear. We investigated the response to tension release, with regard to matrix proteins, pro...... were upregulated. Stimulation with the cytokine TGF-β1 had distinct effects on some tendon-related genes in both tensioned and de-tensioned tissue. These findings indicate an important role of mechanical loading for cellular and matrix responses in tendon, including that loss of tension leads...

  20. Postnatal development of resistance to short-term high-dose toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin in TCDD-resistant and -semiresistant rats

    International Nuclear Information System (INIS)

    Simanainen, Ulla; Tuomisto, Jouni T.; Pohjanvirta, Raimo; Syrjaelae, Paula; Tuomisto, Jouko; Viluksela, Matti

    2004-01-01

    Despite great interspecies differences in adult 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) sensitivity, the toxic potency of TCDD is similar across species in fetal mortality. Han/Wistar (Kuopio; H/W) rats are exceptionally resistant to acute toxicity of TCDD, but show sensitivity to embryotoxicity and teratogenicity. The resistance of adult H/W rats to acute TCDD toxicity is based on a point mutation in the transactivation domain of the aryl hydrocarbon receptor (AHR) and to an unknown gene ''B''. This study investigated the time course of postnatal development of resistance to TCDD and the significance of genotypic variation in resistance development. H/W, line A (a new line with the H/W-type mutated AHR), and line B rats (a line with normal AHR but moderately resistant because of gene ''B'') were exposed to a single dose of TCDD 2-56 days after birth. H/W and line A rats received 1000 μg/kg; male and female B rats received 200 and 100 μg/kg, respectively. Survival was monitored for 42 days. Interestingly, although TCDD ceased growth and weight gain in all TCDD groups, the younger dosed animals did not seem to reach the body weight of the older dosed animals even in 100 days. The survival results after 42 days showed that line A rats are fairly resistant to TCDD immediately after birth, and their full TCDD resistance develops during the first week of life. The moderate resistance of line B rats develops approximately at the time of weaning. This difference in the time course of resistance development suggests that there are basic differences in pathways mediating resistance in lines A and B rats

  1. Matrix cross-linking lysyl oxidases are induced in response to myocardial infarction and promote cardiac dysfunction

    NARCIS (Netherlands)

    González-Santamaría, J.; Villalba, M.; Busnadiego, O.; López-Olañeta, M.M.; Sandoval, P.; Snabel, J.; López-Cabrera, M.; Erler, J.T.; Hanemaaijer, R.; Lara-Pezzi, E.; Rodríguez-Pascual, F.

    2016-01-01

    Aims After myocardial infarction (MI), extensive remodelling of the extracellular matrix contributes to scar formation. While aiming to preserve tissue integrity, this fibrotic response is also associated with adverse events, including a markedly increased risk of heart failure, ventricular

  2. Leukocyte-derived and endogenous matrix metalloproteinases in the lamellae of horses with naturally acquired and experimentally induced laminitis.

    Science.gov (United States)

    Loftus, John P; Johnson, Philip J; Belknap, James K; Pettigrew, Amanda; Black, Samuel J

    2009-06-15

    Inflammation and dysregulation of endogenous matrix metalloproteinase (MMP) production are implicated in the development of equine laminitis. In this study, we examine quantitative relationships among levels of leukocyte-derived proMMP-9 and MMP-9, lamellar proMMP-2 and MMP-2, and expression of proMMP-2 processing enzymes, MT1-MMP/PACE4, as steps towards determining whether inflammation and dysregulation of endogenous MMP production are independent or co-dependent processes. Archived samples of lamellae from horses with naturally acquired laminitis (n = 12), and from horses administered a pro-laminitic gastric bolus of starch gruel were used, the latter horses falling into two groups: (i) responders (CHO-R, n = 7), which developed Obel grade 3-lameness and (ii) non-responders (CHO-NR, n = 4), which did not become lame. Lamellar tissue extracts were analyzed by gelatin zymography to determine gelatinase content and by a myeloperoxidase ELISA to quantify relative monocyte/neutrophil content in the tissue. Real-time PCR was employed to measure gene expression of MT1-MMP and PACE4. Extracts of lamellae from control horses, CHO-NR and horses with chronic (non-aggravated) laminitis had similarly low levels of pro and processed MMP-9 and MMP-2. In contrast, proMMP-9 was significantly elevated in extracts of lamellae from CHO-R and horses with naturally acquired acute and aggravated chronic laminitis. Lamellar MMP-2 was also increased significantly in the CHO-R and aggravated chronic laminitis groups, although not in the horses with naturally acquired acute laminitis. Concentrations of proMMP-9 correlated directly with myeloperoxidase content in lamellar extracts, suggesting production/induction by inflammatory leukocytes. In contrast, concentrations of proMMP-2 and MMP-2 were unrelated to concentrations of myeloperoxidase or proMMP-9 suggesting that leukocyte infiltration and dysregulation of endogenous MMP-2 are independent processes most likely with distinct inducers

  3. Incidence, degree, and development of graft hypertrophy 24 months after matrix-induced autologous chondrocyte implantation: association with clinical outcomes.

    Science.gov (United States)

    Ebert, Jay R; Smith, Anne; Fallon, Michael; Butler, Rodney; Nairn, Robert; Breidahl, William; Wood, David J

    2015-09-01

    Graft hypertrophy is a common occurrence after periosteal, collagen-covered and matrix-induced autologous chondrocyte implantation (MACI). The purpose of this study was to investigate the incidence, development, and degree of graft hypertrophy at 24 months after MACI. The hypothesis was that graft hypertrophy would not be associated with clinical outcome at 24 months. Case series, Level of evidence, 4. This study was undertaken in 180 consecutive patients (113 male, 67 female) after MACI in the knee. All patients were assessed clinically using the Knee injury and Osteoarthritis Outcome Score (KOOS) and underwent magnetic resonance imaging (MRI) at 3, 12, and 24 months after surgery. The incidence of hypertrophy relevant to anatomic graft site was investigated, as was the progressive change in hypertrophic studies postoperatively. The degree of tissue overgrowth in hypertrophic cases was investigated, as was its association with patient clinical outcome at 24 months after surgery. Of the 180 patients, 50 demonstrated a hypertrophic graft at 1 or more postoperative time points. This included 9 grafts (5.0%) at 3 months and 32 grafts (18.7%) at 12 months. At 24 months, 47 grafts (26.1%)-43 (32.1%) tibiofemoral and 4 (8.7%) patellofemoral-were hypertrophic. Patients with hypertrophic grafts at 24 months (n = 47) were younger (P = .051), they had a lower body mass index (BMI; P = .069), and significantly fewer of them had patellofemoral grafts (P = .007) compared with patients who had grafts with full (100%) tissue infill (n = 61). There were no significant differences in any of the KOOS subscales between patients with graft hypertrophy or full (100%) tissue infill at 24 months after surgery, while the severity of graft hypertrophy was not associated with KOOS subscales at 24 months. Hypertrophic grafts after MACI were common and continued to develop through to 24 months after surgery. Hypertrophic growth was associated with being younger and having a lower BMI, was

  4. The HIV matrix protein p17 subverts nuclear receptors expression and induces a STAT1-dependent proinflammatory phenotype in monocytes.

    Directory of Open Access Journals (Sweden)

    Barbara Renga

    Full Text Available BACKGROUND: Long-term remission of HIV-1 disease can be readily achieved by combinations of highly effective antiretroviral therapy (HAART. However, a residual persistent immune activation caused by circulating non infectious particles or viral proteins is observed under HAART and might contribute to an higher risk of non-AIDS pathologies and death in HIV infected persons. A sustained immune activation supports lipid dysmetabolism and increased risk for development of accelerated atehrosclerosis and ischemic complication in virologically suppressed HIV-infected persons receiving HAART. AIM: While several HIV proteins have been identified and characterized for their ability to maintain immune activation, the role of HIV-p17, a matrix protein involved in the viral replication, is still undefined. RESULTS: Here, we report that exposure of macrophages to recombinant human p17 induces the expression of proinflammatory and proatherogenic genes (MCP-1, ICAM-1, CD40, CD86 and CD36 while downregulating the expression of nuclear receptors (FXR and PPARγ that counter-regulate the proinflammatory response and modulate lipid metabolism in these cells. Exposure of macrophage cell lines to p17 activates a signaling pathway mediated by Rack-1/Jak-1/STAT-1 and causes a promoter-dependent regulation of STAT-1 target genes. These effects are abrogated by sera obtained from HIV-infected persons vaccinated with a p17 peptide. Ligands for FXR and PPARγ counteract the effects of p17. CONCLUSIONS: The results of this study show that HIV p17 highjacks a Rack-1/Jak-1/STAT-1 pathway in macrophages, and that the activation of this pathway leads to a simultaneous dysregulation of immune and metabolic functions. The binding of STAT-1 to specific responsive elements in the promoter of PPARγ and FXR and MCP-1 shifts macrophages toward a pro-atherogenetic phenotype characterized by high levels of expression of the scavenger receptor CD36. The present work identifies p17 as a

  5. Correlation Between Clinical and Radiological Outcomes After Matrix-Induced Autologous Chondrocyte Implantation in the Femoral Condyles.

    Science.gov (United States)

    Ebert, Jay R; Smith, Anne; Fallon, Michael; Wood, David J; Ackland, Timothy R

    2014-08-01

    Matrix-induced autologous chondrocyte implantation (MACI) is an established technique for the repair of knee chondral defects, although the correlation between clinical and radiological outcomes after surgery is poorly understood. To determine the correlation between clinical and radiological outcomes throughout the postoperative timeline to 5 years after MACI. Cohort study (diagnosis); Level of evidence, 3. This retrospective study was undertaken in 83 patients (53 male, 30 female) with complete clinical and radiological follow-up at 1, 2, and 5 years after MACI. The mean age of patients was 38.9 years (range, 13-62 years), with a mean body mass index (BMI) of 26.6 kg/m(2) (range, 16.8-34.8 kg/m(2)), mean defect size of 3.3 cm(2) (range, 1-9 cm(2)), and mean preoperative duration of symptoms of 9.2 years (range, 1-46 years). Patients indicated for MACI in this follow-up were 13 to 65 years of age, although they were excluded if they had a BMI >35 kg/m(2), had undergone prior extensive meniscectomy, or had ongoing progressive inflammatory arthritis. Patients were assessed clinically using the Knee Injury and Osteoarthritis Outcome Score (KOOS). Magnetic resonance imaging (MRI) was used to evaluate the graft using a 1.5-T or 3-T clinical scanner; the MRI assessment included 8 parameters of graft repair (infill, signal intensity, border integration, surface contour, structure, subchondral lamina, subchondral bone, and effusion) based on the magnetic resonance observation of cartilage repair tissue (MOCART) score as well as an MRI composite score. The degree of an association between the MRI parameters and the KOOS subscales at each postoperative time point was assessed with the Spearman correlation coefficient (SCC), and significance was determined at P correlations over time and statistically significant associations at 5 years with KOOS-Pain (SCC, 0.25; P = .020), KOOS-Activities of Daily Living (SCC, 0.26; P = .018), and KOOS-Sport (SCC, 0.32; P = .003). Apart

  6. Matrix metalloproteinase 12 is induced by heterogeneous nuclear ribonucleoprotein K and promotes migration and invasion in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Chung, I-Che; Li, Hsin-Pai; Chang, Yu-Sun; Chen, Lih-Chyang; Chung, An-Ko; Chao, Mei; Huang, Hsin-Yi; Hsueh, Chuen; Tsang, Ngan-Ming; Chang, Kai-Ping; Liang, Ying

    2014-01-01

    Overexpression of heterogeneous nuclear ribonucleoprotein K (hnRNP K), a DNA/RNA binding protein, is associated with metastasis in nasopharyngeal carcinoma (NPC). However, the mechanisms underlying hnRNP K-mediated metastasis is unclear. The aim of the present study was to determine the role of matrix metalloproteinase (MMP) in hnRNP K-mediated metastasis in NPC. We studied hnRNP K-regulated MMPs by analyzing the expression profiles of MMP family genes in NPC tissues and hnRNP K-knockdown NPC cells using Affymetrix microarray analysis and quantitative RT-PCR. The association of hnRNP K and MMP12 expression in 82 clinically proven NPC cases was determined by immunohistochemical analysis. The hnRNP K-mediated MMP12 regulation was determined by zymography and Western blot, as well as by promoter, DNA pull-down and chromatin immunoprecipitation (ChIP) assays. The functional role of MMP12 in cell migration and invasion was demonstrated by MMP12-knockdown and the treatment of MMP12-specific inhibitor, PF-356231. MMP12 was overexpressed in NPC tissues, and this high level of expression was significantly correlated with high-level expression of hnRNP K (P = 0.026). The levels of mRNA, protein and enzyme activity of MMP12 were reduced in hnRNP K-knockdown NPC cells. HnRNP K interacting with the region spanning −42 to −33 bp of the transcription start site triggered transcriptional activation of the MMP12 promoter. Furthermore, inhibiting MMP12 by MMP12 knockdown and MMP12-specific inhibitor, PF-356231, significantly reduced the migration and invasion of NPC cells. Overexpression of MMP12 was significantly correlated with hnRNP K in NPC tissues. HnRNP K can induce MMP12 expression and enzyme activity through activating MMP12 promoter, which promotes cell migration and invasion in NPC cells. In vitro experiments suggest that NPC metastasis with high MMP12 expression may be treated with PF-356231. HnRNP K and MMP12 may be potential therapeutic markers for NPC, but

  7. Nicotine-induced retardation of chondrogenesis through down-regulation of IGF-1 signaling pathway to inhibit matrix synthesis of growth plate chondrocytes in fetal rats

    International Nuclear Information System (INIS)

    Deng, Yu; Cao, Hong; Cu, Fenglong; Xu, Dan; Lei, Youying; Tan, Yang; Magdalou, Jacques; Wang, Hui; Chen, Liaobin

    2013-01-01

    Previous studies have confirmed that maternal tobacco smoking causes intrauterine growth retardation (IUGR) and skeletal growth retardation. Among a multitude of chemicals associated with cigarette smoking, nicotine is one of the leading candidates for causing low birth weights. However, the possible mechanism of delayed chondrogenesis by prenatal nicotine exposure remains unclear. We investigated the effects of nicotine on fetal growth plate chondrocytes in vivo and in vitro. Rats were given 2.0 mg/kg·d of nicotine subcutaneously from gestational days 11 to 20. Prenatal nicotine exposure increased the levels of fetal blood corticosterone and resulted in fetal skeletal growth retardation. Moreover, nicotine exposure induced the inhibition of matrix synthesis and down-regulation of insulin-like growth factor 1 (IGF-1) signaling in fetal growth plates. The effects of nicotine on growth plates were studied in vitro by exposing fetal growth plate chondrocytes to 0, 1, 10, or 100 μM of nicotine for 10 days. Nicotine inhibited matrix synthesis and down-regulated IGF-1 signaling in chondrocytes in a concentration-dependent manner. These results suggest that prenatal nicotine exposure induces delayed chondrogenesis and that the mechanism may involve the down-regulation of IGF-1 signaling and the inhibition of matrix synthesis by growth plate chondrocytes. The present study aids in the characterization of delayed chondrogenesis caused by prenatal nicotine exposure, which might suggest a candidate mechanism for intrauterine origins of osteoporosis and osteoarthritis. - Highlights: ► Prenatal nicotine-exposure could induce delayed chondrogenesis in fetal rats. ► Nicotine inhibits matrix synthesis of fetal growth plate chondrocytes. ► Nicotine inhibits IGF-1 signaling pathway in fetal growth plate chondrocytes

  8. Nicotine-induced retardation of chondrogenesis through down-regulation of IGF-1 signaling pathway to inhibit matrix synthesis of growth plate chondrocytes in fetal rats

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Yu; Cao, Hong; Cu, Fenglong [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Xu, Dan [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China); Lei, Youying [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Tan, Yang [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Magdalou, Jacques [UMR 7561 CNRS-Nancy Université, Faculté de Médicine, Vandoeuvre-lès-Nancy (France); Wang, Hui [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China); Chen, Liaobin, E-mail: lbchen@whu.edu.cn [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China)

    2013-05-15

    Previous studies have confirmed that maternal tobacco smoking causes intrauterine growth retardation (IUGR) and skeletal growth retardation. Among a multitude of chemicals associated with cigarette smoking, nicotine is one of the leading candidates for causing low birth weights. However, the possible mechanism of delayed chondrogenesis by prenatal nicotine exposure remains unclear. We investigated the effects of nicotine on fetal growth plate chondrocytes in vivo and in vitro. Rats were given 2.0 mg/kg·d of nicotine subcutaneously from gestational days 11 to 20. Prenatal nicotine exposure increased the levels of fetal blood corticosterone and resulted in fetal skeletal growth retardation. Moreover, nicotine exposure induced the inhibition of matrix synthesis and down-regulation of insulin-like growth factor 1 (IGF-1) signaling in fetal growth plates. The effects of nicotine on growth plates were studied in vitro by exposing fetal growth plate chondrocytes to 0, 1, 10, or 100 μM of nicotine for 10 days. Nicotine inhibited matrix synthesis and down-regulated IGF-1 signaling in chondrocytes in a concentration-dependent manner. These results suggest that prenatal nicotine exposure induces delayed chondrogenesis and that the mechanism may involve the down-regulation of IGF-1 signaling and the inhibition of matrix synthesis by growth plate chondrocytes. The present study aids in the characterization of delayed chondrogenesis caused by prenatal nicotine exposure, which might suggest a candidate mechanism for intrauterine origins of osteoporosis and osteoarthritis. - Highlights: ► Prenatal nicotine-exposure could induce delayed chondrogenesis in fetal rats. ► Nicotine inhibits matrix synthesis of fetal growth plate chondrocytes. ► Nicotine inhibits IGF-1 signaling pathway in fetal growth plate chondrocytes.

  9. Near-infrared radiation induced conformational change and hydrogen atom tunneling of 2-chloropropionic acid in low-temperature Ar matrix.

    Science.gov (United States)

    Bazsó, Gábor; Góbi, Sándor; Tarczay, György

    2012-05-24

    Former assignments of the matrix-isolation infrared (MI-IR) spectrum of 2-chloropropionic acid are revised with the help of near-infrared (NIR) laser irradiation induced change in conformer ratios. This method allows not only the unambiguous assignment of each band in the MI-IR spectrum to the two trans (Z) and the cis (E) conformers but also the assignment of the spectral bands to different matrix sites. The tunneling decay of the higher-energy cis conformer prepared from both trans conformers in different sites is also investigated. It is shown that the tunneling decay time is very sensitive to the matrix site, especially if the in situ prepared high-energy conformer has a strained geometry in the matrix cage. The analysis shows that the kinetics of some cis → trans back conversion processes cannot be fitted by a single exponential decay. The possible reasons of this observation are examined and discussed. The present and former results clearly show that, in addition to tunneling processes, the decay rates strongly depend on solid-state effects. Therefore, simple theoretical predictions of decay rates, which do not take into account the solid-state effects, can only be compared to experimental observations only if experimentally proven that these effects do not significantly affect the experimentally measured tunneling rates.

  10. 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) DISRUPTS EARLY MORPHOGENETIC EVENTS THAT FORM THE LOWER REPRODUCTIVE TRACT IN FEMALE RAT FETUSES

    Science.gov (United States)

    In female rats, in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during critical periods of organogenesis causes a permanent thread of tissue across the vaginal opening, which consists of a core of mesenchyme surrounded by keratinized epithelia. The objective of t...

  11. The Effects of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD on the Mortality and Growth of Two Amphibian Species (Xenopus laevis and Pseudacris triseriata

    Directory of Open Access Journals (Sweden)

    Alex Collier

    2008-12-01

    Full Text Available We observed a slight drop in the growth of Xenopus laevis and Pseudacris triseriata larvae following acute exposure (24-48 h during egg development to three concentrations of TCDD (0.3, 3.0, 30.0 μg/l. Our exposure protocol was modeled on a previous investigation that was designed to mimic the effects of maternal deposition of TCDD. The doses selected were consistent with known rates of maternal transfer between mother and egg using actual adult body burdens from contaminated habitats. Egg and embryonic mortality immediately following exposure increased only among 48 h X. laevis treatments. Control P. triseriata and X. laevis completed metamorphosis more quickly than TCDDtreated animals. The snout-vent length of recently transformed P. triseriata did not differ between treatments although controls were heavier than high-dosed animals. Likewise, the snout-vent length and weight of transformed X. laevis did not differ between control and TCDD treatments. These findings provide additional evidence that amphibians, including P. triseriata and X. laevis are relatively insensitive to acute exposure to TCDD during egg and embryonic development. Although the concentrations selected for this study were relatively high, they were not inconsistent with our current understanding of bioaccumulation via maternal transfer.

  12. 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (TCDD) Dose-Response Studies: Preliminary Literature Search Results and Request for Additional Studies

    Science.gov (United States)

    EPA invited the public to comment on the preliminary list of in vivo mammalian dose-response citations for 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). This list was compiled as a first step in the development of EPA’s response to the National Academy of Sciences comments (NAS, 2...

  13. Modeling of Ah-receptor dependent P450 induction I. Cellular model definition and its incorporation in a PBPK model of 2,3,7,8-TCDD

    NARCIS (Netherlands)

    Zeilmaker MJ; Eijkeren JCH van; LBO

    1997-01-01

    The interspecies extrapolation of chemical toxicity is traditionally based on the daily administered dose of the chemical. However, in the case of compounds with strong bioaccumulating properties, such as 2,3,7,8-TetraChloroDibenzo-p-Dioxin (TCDD), chronic toxicity is expected to scale better with

  14. Exposure of human JEG-3 cell line to TCDD alters progesterone secretion but does not act on their viability and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Augustowska, K.; Gregoraszczuk, E.L. [Jagiellonian Univ., Krakow (Poland)

    2004-09-15

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds are lipophilic and difficult to metabolize. Any environmental exposure of living organisms to these congeners results in their accumulation in fat tissue and bioconcentration in humans via the food chain. TCDD acts as an endocrine disrupter to alter differentiation and function of the reproductive system. Therefore, these compounds represent a serious health risk, especially to the fetus and infants, whose enzymatic and metabolic systems are not yet mature. Our previous data showed high accumulation of TCDD in cultured human placental tissue which caused a decrease in hormone secretion. However, the mechanism of this action is still unclear. JEG-3 cell line from malignant placental tissue has been used as an in vitro model for investigation of the effects of xenobiotics on placenta toxicity. These cells are morphologically similar to their origin, the trophoblast of the normal first trimester placenta, and produce many peptides and steroid hormones found in normal trophoblast cells, such as hCG, GhRH, progesterone. The aim of the present study was firstly, to show dose- and time-dependent effects of TCDD on progesterone production by JEG-3 cells and secondly, to examine mechanism of its action on cell viability and apoptosis.

  15. Restoration of dioxin-induced damage to fetal steroidogenesis and gonadotropin formation by maternal co-treatment with α-lipoic acid.

    Directory of Open Access Journals (Sweden)

    Takayuki Koga

    Full Text Available 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD, an endocrine disruptor, causes reproductive and developmental toxic effects in pups following maternal exposure in a number of animal models. Our previous studies have demonstrated that TCDD imprints sexual immaturity by suppressing the expression of fetal pituitary gonadotropins, the regulators of gonadal steroidogenesis. In the present study, we discovered that all TCDD-produced damage to fetal production of pituitary gonadotropins as well as testicular steroidogenesis can be repaired by co-treating pregnant rats with α-lipoic acid (LA, an obligate co-factor for intermediary metabolism including energy production. While LA also acts as an anti-oxidant, other anti-oxidants; i.e., ascorbic acid, butylated hydroxyanisole and edaravone, failed to exhibit any beneficial effects. Neither wasting syndrome nor CYP1A1 induction in the fetal brain caused through the activation of aryl hydrocarbon receptor (AhR could be attenuated by LA. These lines of evidence suggest that oxidative stress makes only a minor contribution to the TCDD-induced disorder of fetal steroidogenesis, and LA has a restorative effect by targeting on mechanism(s other than AhR activation. Following a metabolomic analysis, it was found that TCDD caused a more marked change in the hypothalamus, a pituitary regulator, than in the pituitary itself. Although the components of the tricarboxylic acid cycle and the ATP content of the fetal hypothalamus were significantly changed by TCDD, all these changes were again rectified by exogenous LA. We also provided evidence that the fetal hypothalamic content of endogenous LA is significantly reduced following maternal exposure to TCDD. Thus, the data obtained strongly suggest that TCDD reduces the expression of fetal pituitary gonadotropins to imprint sexual immaturity or disturb development by suppressing the level of LA, one of the key players serving energy production.

  16. Exploring the conformational space of cysteine by matrix isolation spectroscopy combined with near-infrared laser induced conformational change.

    Science.gov (United States)

    Najbauer, Eszter E; Bazsó, Gábor; Góbi, Sándor; Magyarfalvi, Gábor; Tarczay, György

    2014-02-27

    Six conformers of α-cysteine were identified by matrix isolation IR spectroscopy combined with NIR laser irradiation. Five of these conformers are identical with the five out of six conformers that have recently been identified by microwave spectroscopy. The sixth conformer observed in the present study is a short-lived conformer, which decays by H-atom tunneling; its half-life in a 12 K N2 matrix is (1.1 ± 0.5) × 10(3) s. This study proves that matrix isolation IR spectroscopy combined with NIR laser irradiation is a suitable method to identify conformers of a complex system for which computations predict several dozens of conformers, and that the reliability of this method for conformational assignment is comparable to that of microwave spectroscopy.

  17. Mueller-matrix of laser-induced autofluorescence of polycrystalline films of dried peritoneal fluid in diagnostics of endometriosis

    Science.gov (United States)

    Ushenko, Yuriy A.; Koval, Galina D.; Ushenko, Alexander G.; Dubolazov, Olexander V.; Ushenko, Vladimir A.; Novakovskaia, Olga Yu.

    2016-07-01

    This research presents investigation results of the diagnostic efficiency of an azimuthally stable Mueller-matrix method of analysis of laser autofluorescence of polycrystalline films of dried uterine cavity peritoneal fluid. A model of the generalized optical anisotropy of films of dried peritoneal fluid is proposed in order to define the processes of laser autofluorescence. The influence of complex mechanisms of both phase (linear and circular birefringence) and amplitude (linear and circular dichroism) anisotropies is taken into consideration. The interconnections between the azimuthally stable Mueller-matrix elements characterizing laser autofluorescence and different mechanisms of optical anisotropy are determined. The statistical analysis of coordinate distributions of such Mueller-matrix rotation invariants is proposed. Thereupon the quantitative criteria (statistic moments of the first to the fourth order) of differentiation of polycrystalline films of dried peritoneal fluid, group 1 (healthy donors) and group 2 (uterus endometriosis patients), are determined.

  18. Increased cAMP levels modulate transforming growth factor-beta/Smad-induced expression of extracellular matrix components and other key fibroblast effector functions.

    Science.gov (United States)

    Schiller, Meinhard; Dennler, Sylviane; Anderegg, Ulf; Kokot, Agatha; Simon, Jan C; Luger, Thomas A; Mauviel, Alain; Böhm, Markus

    2010-01-01

    cAMP is a key messenger of many hormones and neuropeptides, some of which modulate the composition of extracellular matrix. Treatment of human dermal fibroblasts with dibutyryl cyclic AMP and forskolin antagonized the inductive effects of transforming growth factor-beta (TGF-beta) on the expression of collagen, connective tissue growth factor, tissue inhibitor of matrix metalloproteinase-1, and plasminogen activator inhibitor type I, four prototypical TGF-beta-responsive genes. Increased intracellular cAMP prevented TGF-beta-induced Smad-specific gene transactivation, although TGF-beta-mediated Smad phosphorylation and nuclear translocation remained unaffected. However, increased cAMP levels abolished TGF-beta-induced interaction of Smad3 with its transcriptional co-activator cAMP-response element-binding protein (CREB)-binding protein (CBP)/p300. Overexpression of the transcriptional co-activator CBP/p300 rescued Smad-specific gene transcription in the presence of cAMP suggesting that sequestration of limited amounts of CBP/p300 by the activated cAMP/CREB pathway is the molecular basis of this inhibitory effect. These findings were extended by two functional assays. Increased intracellular cAMP levels suppressed the inductive activity of TGF-beta to contract mechanically unloaded collagen lattices and resulted in an attenuation of fibroblast migration of mechanically induced cell layer wounds. Of note, cAMP and TGF-beta synergistically induced hyaluronan synthase 2 (HAS2) expression and hyaluronan secretion, presumably via putative CREB-binding sites adjacent to Smad-binding sites within the HAS2 promoter. Our findings identify the cAMP pathway as a potent but differential and promoter-specific regulator of TGF-beta-mediated effects involved in extracellular matrix homeostasis.

  19. ADAM12 induces actin cytoskeleton and extracellular matrix reorganization during early adipocyte differentiation by regulating beta1 integrin function

    DEFF Research Database (Denmark)

    Kawaguchi, Nobuko; Sundberg, Christina; Kveiborg, Marie

    2003-01-01

    . Moreover, ADAM12-expressing cells were more prone to apoptosis, which could be prevented by treating the cells with beta1-activating antibodies. A reduced and re-organized fibronectin-rich extracellular matrix accompanied these changes. In addition, beta1 integrin was more readily extracted with Triton X......-100 from cells overexpressing ADAM12 than from control cells. Collectively, these results show that surface expression of ADAM12 impairs the function of beta1 integrins and, consequently, alters the organization of the actin cytoskeleton and extracellular matrix. These events may be necessary...

  20. Matrix theory

    CERN Document Server

    Franklin, Joel N

    2003-01-01

    Mathematically rigorous introduction covers vector and matrix norms, the condition-number of a matrix, positive and irreducible matrices, much more. Only elementary algebra and calculus required. Includes problem-solving exercises. 1968 edition.

  1. Changes induced by gamma radiation in nanocomposites based on copper II and antimony sulfides in commercial poly(methyl methacrylate) matrix

    International Nuclear Information System (INIS)

    Albuquerque, M.C.C. de; Garcia, O.P.; Aquino, K.A.S.; Araujo, E.S.

    2010-01-01

    Poly (methyl methacrylate) (PMMA) is a polymer with wide application in the manufacture of medical devices that is exposed to gamma irradiation. Currently the use of composite materials has been disseminated and PMMA is an excellent polymer matrix to package various materials. This study aimed to analyze the changes induced by gamma irradiation (25 kGy) on the properties of PMMA nanocomposites with nanoparticles of copper II sulfide (250nm-900nm) and antimony sulfite (300-500 nm). The nanoparticles were added to the polymer in different concentrations and synthesized by ultrasonic irradiation from the corresponding chlorides with thioacetamide. Viscometric results showed a good radioprotective effect of nanoparticles of copper and antimony. It was found a good protection of nanoparticles on PMMA matrix in the concentration of 0.3% wt. The protections of 75% and 50% were calculated for nanoparticles of antimony and copper II, respectively. (author)

  2. In utero and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) affects tooth development in rhesus monkeys

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, Iku; Kazuhiro, Tsuga; Yasumasa, Akagawa [Hiroshima Univ. (Japan); Mineo, Yasuda; Hiroshi, Sumida [Hiroshima International Univ. (Japan); Akihiro, Arima; Toshio, Ihara [Shin Nippon Biomedical Laboratories, Ltd., Kagoshima (Japan); Shunichiro, Kubota [Tokyo Univ. (Japan); Kazuo, Asaoka [Kyoto Univ., Inuyama (Japan). Primate Research Institute; Takumi, Takasuga [Shimadzu Techno-Research Inc., Kyoto (Japan)

    2004-09-15

    The current tolerable daily intake (TDI) of dioxin and dioxin related compounds has been set at 4 pg TEQ/kg/day in Japan. This value was calculated from the lowest-observed-adverse-effect level (LOAEL) in experimental animals, mostly rodents. Gray et al. reported that a single oral dose of 200 ng/kg of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to pregnant rats on day 15 of gestation resulted in abnormalities of reproductive organs in the offspring. The maternal body burden at this dose was measured to be 86 ng/kg. To attain this body burden level, human daily intake was calculated to be 43.6 pg/kg/day. An uncertainty factor of 10 was applied to this value, and the human TDI was established. However, due to great differences in the biological half life of TCDD between human and rodents, the validity of this calculation is questioned. To obtain more reliable LOAEL in the second generation, we initiated a long-term study in rhesus monkeys in 1999. In rodents, teeth are known to be targets of developmental toxicity of dioxin. In utero and lactational TCDD exposure affects rat incisor and molar development. In humans also tooth abnormalities were reported among populations exposed to dioxins. In our monkey experiment, some young were stillborn or died neonatally. These animals provided us with a unique opportunity to study tooth development in primate young exposed to TCDD in utero and lactationally. By macroscopic observation we found some tooth abnormalities among died young exposed to TCDD5. This prompted us to examine surviving young by radiography. This is an interim report of our findings in these young.

  3. Synthetic inhibitors of matrix metalloproteinases prevent sulfur mustard-induced epidermal-dermal separation in human skin pieces

    NARCIS (Netherlands)

    Mol, M.A.E.; Alblas, S.W.; Hammer, A.; Benschop, H.P.

    2000-01-01

    Degradation of proteins of the basement membrane zone (BMZ) in the skin depends on the activity of proteolytic enzymes, particularly those belonging to the group of matrix metalloproteinases (MMPs). In the present study we have investigated the contribution of these enzymes to the epidermal-dermal

  4. Microwave induced hierarchical nanostructures on aramid fibers and their influence on adhesion properties in a rubber matrix

    Energy Technology Data Exchange (ETDEWEB)

    Palola, S., E-mail: sarianna.palola@tut.fi [Laboratory of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere (Finland); Institute for Materials and Processes, School of Engineering, The University of Edinburgh, The King' s Buildings, Robert Stevenson Road, EH9 3FB Edinburgh (United Kingdom); Sarlin, E. [Laboratory of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere (Finland); Kolahgar Azari, S.; Koutsos, V. [Institute for Materials and Processes, School of Engineering, The University of Edinburgh, The King' s Buildings, Robert Stevenson Road, EH9 3FB Edinburgh (United Kingdom); Vuorinen, J. [Laboratory of Materials Science, Tampere University of Technology, P.O. Box 589, 33101, Tampere (Finland)

    2017-07-15

    Highlights: • A novel method for creating nanostructures to aramid fiber surface is proposed. • The nanostructures enable mechanical interlocking at fiber-matrix interface. • A ∼250% increase in adhesion can be created with this method. - Abstract: Several commercial surface treatments are used to increase the adhesion between aramid fibers and the matrix material in composite structures but each of these has some limitations. The aim of this study is to address some of these limitations by developing a surface treatment method for aramid fibers that would not affect mechanical properties of the fibers negatively, could be used with any matrix material and that could withstand handling of the fibers and ageing. The method used is microwave assisted surface treatment that uses microwave radiation together with dry reactive chemicals to create hierarchical structures to the fiber surface and so makes it possible to control the adhesion properties of the fibers. SEM and AFM imaging, fiber tensile tests and modified bundle pull-out test were used to investigate the outcome of the surface treatment and measure adhesion between aramid fiber bundles and rubber. SEM and AFM imaging revealed that nanoscale deposits are formed on to the fiber surface which enable mechanical interlocking between the fiber and the matrix material. Fiber tensile tests showed that the surface treatment does not influence the tensile properties of the fiber negatively. Results from the bundle pull-out tests confirmed that this kind of method can lead up to 259% improvement in adhesion when compared to untreated aramid fibers in the rubber matrix.

  5. Anandamide induces matrix metalloproteinase-2 production through cannabinoid-1 receptor and transient receptor potential vanilloid-1 in human dental pulp cells in culture.

    Science.gov (United States)

    Miyashita, Keiko; Oyama, Tohru; Sakuta, Tetsuya; Tokuda, Masayuki; Torii, Mitsuo

    2012-06-01

    Anandamide (N-arachidonoylethanolamine [AEA]) is one of the main endocannabinoids. Endocannabinoids are implicated in various physiological and pathologic functions, inducing not only nociception but also regeneration and inflammation. The role of the endocannabinoid system in peripheral organs was recently described. The aim of this study was to investigate the effect of AEA on matrix metalloproteinase (MMP)-2 induction in human dental pulp cells (HPC). We examined AEA-induced MMP-2 production and the expression of AEA receptors (cannabinoid [CB] receptor-1, CB2, and transient receptor potential vanilloid-1 [TRPV1]) in HPC by Western blot. MMP-2 concentrations in supernatants were determined by enzyme-linked immunosorbent assay. We then investigated the role of the AEA receptors and mitogen-activated protein kinase in AEA-induced MMP-2 production in HPC. AEA significantly induced MMP-2 production in HPC. HPC expressed all 3 types of AEA receptor (CB1, CB2, and TRPV1). AEA-induced MMP-2 production was blocked by CB1 or TRPV1 antagonists and by small interfering RNA for CB1 or TRPV1. Furthermore, c-Jun N-terminal kinase inhibitor also reduced MMP-2 production. We demonstrated for the first time that AEA induced MMP-2 production via CB1 and TRPV1 in HPC. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. Estradiol-induced regression in T47D:A18/PKCalpha tumors requires the estrogen receptor and interaction with the extracellular matrix.

    Science.gov (United States)

    Zhang, Yiyun; Zhao, Huiping; Asztalos, Szilard; Chisamore, Michael; Sitabkhan, Yasmin; Tonetti, Debra A

    2009-04-01

    Several breast cancer tumor models respond to estradiol (E(2)) by undergoing apoptosis, a phenomenon known to occur in clinical breast cancer. Before the application of tamoxifen as an endocrine therapy, high-dose E(2) or diethystilbesterol treatment was successfully used, albeit with unfavorable side effects. It is now recognized that such an approach may be a potential endocrine therapy option. We have explored the mechanism of E(2)-induced tumor regression in our T47D:A18/PKCalpha tumor model that exhibits autonomous growth, tamoxifen resistance, and E(2)-induced tumor regression. Fulvestrant, a selective estrogen receptor (ER) down-regulator, prevents T47D:A18/PKCalpha E(2)-induced tumor growth inhibition and regression when given before or after tumor establishment, respectively. Interestingly, E(2)-induced growth inhibition is only observed in vivo or when cells are grown in Matrigel but not in two-dimensional tissue culture, suggesting the requirement of the extracellular matrix. Tumor regression is accompanied by increased expression of the proapoptotic FasL/FasL ligand proteins and down-regulation of the prosurvival Akt pathway. Inhibition of colony formation in Matrigel by E(2) is accompanied by increased expression of FasL and short hairpin RNA knockdown partially reverses colony formation inhibition. Classic estrogen-responsive element-regulated transcription of pS2, PR, transforming growth factor-alpha, C3, and cathepsin D is independent of the inhibitory effects of E(2). A membrane-impermeable E(2)-BSA conjugate is capable of mediating growth inhibition, suggesting the involvement of a plasma membrane ER. We conclude that E(2)-induced T47D:A18/PKCalpha tumor regression requires participation of ER-alpha, the extracellular matrix, FasL/FasL ligand, and Akt pathways, allowing the opportunity to explore new predictive markers and therapeutic targets.

  7. CBP and Extracellular Matrix-Induced Apoptosis in p53(-) HMECs: A Model of Early Mammary Carcinogenesis

    Science.gov (United States)

    2006-09-01

    current prevention strategies. 15. SUBJECT TERMS prevention, CREBP-binding protein, extracellular matrix, apoptosis 16. SECURITY CLASSIFICATION OF...the retention time of Tam and QTam were 4.3 and 4.8min, respectively. QTam was 495% pure by reverse phase HPLC. The high-resolution FAB -MS and [1H]NMR... Leukemia , 11, 2087–2096. Giles RH, Petrij F, Dauwerse HG, den Hollander AI, Lushnikova T, van Ommen GJ, Goodman RH, Deaven LL, Doggett NA, Peters DJ

  8. Dioxin induces Ahr-dependent robust DNA demethylation of the Cyp1a1 promoter via Tdg in the mouse liver

    Science.gov (United States)

    Amenya, Hesbon Z.; Tohyama, Chiharu; Ohsako, Seiichiroh

    2016-10-01

    The aryl hydrocarbon receptor (Ahr) is a highly conserved nuclear receptor that plays an important role in the manifestation of toxicity induced by polycyclic aromatic hydrocarbons. As a xenobiotic sensor, Ahr is involved in chemical biotransformation through activation of drug metabolizing enzymes. The activated Ahr cooperates with coactivator complexes to induce epigenetic modifications at target genes. Thus, it is conceivable that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent Ahr ligand, may elicit robust epigenetic changes in vivo at the Ahr target gene cytochrome P450 1a1 (Cyp1a1). A single dose of TCDD administered to adult mice induced Ahr-dependent CpG hypomethylation, changes in histone modifications, and thymine DNA glycosylase (Tdg) recruitment at the Cyp1a1 promoter in the liver within 24 hrs. These epigenetic changes persisted until 40 days post-TCDD treatment and there was Cyp1a1 mRNA hyperinduction upon repeat administration of TCDD at this time-point. Our demethylation assay using siRNA knockdown and an in vitro methylated plasmid showed that Ahr, Tdg, and the ten-eleven translocation methyldioxygenases Tet2 and Tet3 are required for the TCDD-induced DNA demethylation. These results provide novel evidence of Ahr-driven active DNA demethylation and epigenetic memory. The epigenetic alterations influence response to subsequent chemical exposure and imply an adaptive mechanism to xenobiotic stress.

  9. Inhibition of matrix metalloproteinase-9 activity by doxycycline ameliorates RANK ligand-induced osteoclast differentiation in vitro and in vivo

    International Nuclear Information System (INIS)

    Franco, Gilson C.N.; Kajiya, Mikihito; Nakanishi, Tadashi; Ohta, Kouji; Rosalen, Pedro L.; Groppo, Francisco C.; Ernst, Cory W.O.; Boyesen, Janie L.; Bartlett, John D.; Stashenko, Philip; Taubman, Martin A.; Kawai, Toshihisa

    2011-01-01

    Tetracycline antibiotics, including doxycycli/e (DOX), have been used to treat bone resorptive diseases, partially because of their activity to suppress osteoclastogenesis induced by receptor activator of nuclear factor kappa B ligand (RANKL). However, their precise inhibitory mechanism remains unclear. Therefore, the present study examined the effect of Dox on osteoclastogenesis signaling induced by RANKL, both in vitro and in vivo. Although Dox inhibited RANKL-induced osteoclastogenesis and down-modulated the mRNA expression of functional osteoclast markers, including tartrate-resistant acid phosphatase (TRAP) and cathepsin K, Dox neither affected RANKL-induced MAPKs phosphorylation nor NFATc1 gene expression in RAW264.7 murine monocytic cells. Gelatin zymography and Western blot analyses showed that Dox down-regulated the enzyme activity of RANKL-induced MMP-9, but without affecting its protein expression. Furthermore, MMP-9 enzyme inhibitor also attenuated both RANKL-induced osteoclastogenesis and up-regulation of TRAP and cathepsin K mRNA expression, indicating that MMP-9 enzyme action is engaged in the promotion of RANKL-induced osteoclastogenesis. Finally, Dox treatment abrogated RANKL-induced osteoclastogenesis and TRAP activity in mouse calvaria along with the suppression of MMP9 enzyme activity, again without affecting the expression of MMP9 protein. These findings suggested that Dox inhibits RANKL-induced osteoclastogenesis by its inhibitory effect on MMP-9 enzyme activity independent of the MAPK-NFATc1 signaling cascade.

  10. Inhibition of matrix metalloproteinase-9 activity by doxycycline ameliorates RANK ligand-induced osteoclast differentiation in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Franco, Gilson C.N. [Department of Immunology, Forsyth Institute, Cambridge, MA (United States); Department of Pharmacology, FOP/UNICAMP, Piracicaba, SP (Brazil); Kajiya, Mikihito [Department of Immunology, Forsyth Institute, Cambridge, MA (United States); Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA (United States); Nakanishi, Tadashi [Department of Immunology, Forsyth Institute, Cambridge, MA (United States); Ohta, Kouji [Department of Immunology, Forsyth Institute, Cambridge, MA (United States); Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA (United States); Rosalen, Pedro L.; Groppo, Francisco C. [Department of Pharmacology, FOP/UNICAMP, Piracicaba, SP (Brazil); Ernst, Cory W.O.; Boyesen, Janie L. [Department of Immunology, Forsyth Institute, Cambridge, MA (United States); Bartlett, John D.; Stashenko, Philip [Department of Cytokine Biology, Forsyth Institute, Cambridge, MA (United States); Taubman, Martin A. [Department of Immunology, Forsyth Institute, Cambridge, MA (United States); Kawai, Toshihisa, E-mail: tkawai@forsyth.org [Department of Immunology, Forsyth Institute, Cambridge, MA (United States); Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA (United States)

    2011-06-10

    Tetracycline antibiotics, including doxycycli/e (DOX), have been used to treat bone resorptive diseases, partially because of their activity to suppress osteoclastogenesis induced by receptor activator of nuclear factor kappa B ligand (RANKL). However, their precise inhibitory mechanism remains unclear. Therefore, the present study examined the effect of Dox on osteoclastogenesis signaling induced by RANKL, both in vitro and in vivo. Although Dox inhibited RANKL-induced osteoclastogenesis and down-modulated the mRNA expression of functional osteoclast markers, including tartrate-resistant acid phosphatase (TRAP) and cathepsin K, Dox neither affected RANKL-induced MAPKs phosphorylation nor NFATc1 gene expression in RAW264.7 murine monocytic cells. Gelatin zymography and Western blot analyses showed that Dox down-regulated the enzyme activity of RANKL-induced MMP-9, but without affecting its protein expression. Furthermore, MMP-9 enzyme inhibitor also attenuated both RANKL-induced osteoclastogenesis and up-regulation of TRAP and cathepsin K mRNA expression, indicating that MMP-9 enzyme action is engaged in the promotion of RANKL-induced osteoclastogenesis. Finally, Dox treatment abrogated RANKL-induced osteoclastogenesis and TRAP activity in mouse calvaria along with the suppression of MMP9 enzyme activity, again without affecting the expression of MMP9 protein. These findings suggested that Dox inhibits RANKL-induced osteoclastogenesis by its inhibitory effect on MMP-9 enzyme activity independent of the MAPK-NFATc1 signaling cascade.

  11. CopA3 Peptide Prevents Ultraviolet-Induced Inhibition of Type-I Procollagen and Induction of Matrix Metalloproteinase-1 in Human Skin Fibroblasts

    Directory of Open Access Journals (Sweden)

    Dong-Hee Kim

    2014-05-01

    Full Text Available Ultraviolet (UV exposure is well-known to induce premature aging, which is mediated by matrix metalloproteinase-1 (MMP-1 activity. A 9-mer peptide, CopA3 (CopA3 was synthesized from a natural peptide, coprisin, which is isolated from the dung beetle Copris tripartitus. As part of our continuing search for novel bioactive natural products, CopA3 was investigated for its in vitro anti-skin photoaging activity. UV-induced inhibition of type-I procollagen and induction of MMP-1 were partially prevented in human skin fibroblasts by CopA3 peptide in a dose-dependent manner. At a concentration of 25 μM, CopA3 nearly completely inhibited MMP-1 expression. These results suggest that CopA3, an insect peptide, is a potential candidate for the prevention and treatment of skin aging.

  12. Galangin and kaempferol suppress phorbol-12-myristate-13-acetate-induced matrix metalloproteinase-9 expression in human fibrosarcoma HT-1080 cells.

    Science.gov (United States)

    Choi, Yu Jung; Lee, Young Hun; Lee, Seung-Taek

    2015-01-01

    Matrix metalloproteinase (MMP)-9 degrades type IV collagen in the basement membrane and plays crucial roles in several pathological implications, including tumorigenesis and inflammation. In this study, we analyzed the effect of flavonols on MMP-9 expression in phorbol-12-myristate-13-acetate (PMA)-induced human fibrosarcoma HT-1080 cells. Galangin and kaempferol efficiently decreased MMP-9 secretion, whereas fisetin only weakly decreased its secretion. Galangin and kaempferol did not affect cell viability at concentrations up to 30 μM. Luciferase reporter assays showed that galangin and kaempferol decrease transcription of MMP-9 mRNA. Moreover, galangin and kaempferol strongly reduce IκBα phosphorylation and significantly decrease JNK phosphorylation. These results indicate that galangin and kaempferol suppress PMA-induced MMP-9 expression by blocking activation of NF-κB and AP-1. Therefore, these flavonols could be used as chemopreventive agents to lower the risk of diseases involving MMP-9.

  13. The PI3K/Akt Signaling Pathway Mediates the High Glucose-Induced Expression of Extracellular Matrix Molecules in Human Retinal Pigment Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Dong Qin

    2015-01-01

    Full Text Available Prolonged hyperglycemia is an important risk factor of the pathogenesis of diabetic retinopathy (DR. Extracellular matrix molecules, such as fibronectin, collagen IV, and laminin, are associated with fibrotic membranes. In this study, we investigated the expression of fibronectin, collagen IV, and laminin in RPE cells under high glucose conditions. Furthermore, we also detected the phosphorylation of protein kinase B (Akt under high glucose conditions in RPE cells. Our results showed that high glucose upregulated fibronectin, collagen IV, and laminin expression, and activated Akt in RPE cells. We also found that pretreatment with LY294002 (an inhibitor of phosphatidylinositol 3-kinase abolished high glucose-induced expression of fibronectin, collagen IV, and laminin in RPE cells. Thus, high glucose induced the expression of fibronectin, collagen IV, and laminin through PI3K/Akt signaling pathway in RPE cells, and the PI3K/Akt signaling pathway may contribute to the formation of fibrotic membrane during the development of DR.

  14. Uncovering the local inelastic interactions during manufacture of ductile cast iron: How the substructure of the graphite particles can induce residual stress concentrations in the matrix

    Science.gov (United States)

    Andriollo, Tito; Hellström, Kristina; Sonne, Mads Rostgaard; Thorborg, Jesper; Tiedje, Niels; Hattel, Jesper

    2018-02-01

    Recent X-ray diffraction (XRD) measurements have revealed that plastic deformation and a residual elastic strain field can be present around the graphite particles in ductile cast iron after manufacturing, probably due to some local mismatch in thermal contraction. However, as only one component of the elastic strain tensor could be obtained from the XRD data, the shape and magnitude of the associated residual stress field have remained unknown. To compensate for this and to provide theoretical insight into this unexplored topic, a combined experimental-numerical approach is presented in this paper. First, a material equivalent to the ductile cast iron matrix is manufactured and subjected to dilatometric and high-temperature tensile tests. Subsequently, a two-scale hierarchical top-down model is devised, calibrated on the basis of the collected data and used to simulate the interaction between the graphite particles and the matrix during manufacturing of the industrial part considered in the XRD study. The model indicates that, besides the viscoplastic deformation of the matrix, the effect of the inelastic deformation of the graphite has to be considered to explain the magnitude of the XRD strain. Moreover, the model shows that the large elastic strain perturbations recorded with XRD close to the graphite-matrix interface are not artifacts due to e.g. sharp gradients in chemical composition, but correspond to residual stress concentrations induced by the conical sectors forming the internal structure of the graphite particles. In contrast to common belief, these results thus suggest that ductile cast iron parts cannot be considered, in general, as stress-free at the microstructural scale.

  15. Peroxisome proliferator-activated receptor δ inhibits Porphyromonas gingivalis lipopolysaccharide-induced activation of matrix metalloproteinase-2 by downregulating NADPH oxidase 4 in human gingival fibroblasts.

    Science.gov (United States)

    Yoo, T; Ham, S A; Hwang, J S; Lee, W J; Paek, K S; Oh, J W; Kim, J H; Do, J T; Han, C W; Kim, J H; Seo, H G

    2016-10-01

    We investigated the roles of peroxisome proliferator-activated receptor δ (PPARδ) in Porphyromonas gingivalis-derived lipopolysaccharide (Pg-LPS)-induced activation of matrix metalloproteinase 2 (MMP-2). In human gingival fibroblasts (HGFs), activation of PPARδ by GW501516, a specific ligand of PPARδ, inhibited Pg-LPS-induced activation of MMP-2 and generation of reactive oxygen species (ROS), which was associated with reduced expression of NADPH oxidase 4 (Nox4). These effects were significantly smaller in the presence of small interfering RNA targeting PPARδ or the specific PPARδ inhibitor GSK0660, indicating that PPARδ is involved in these events. In addition, modulation of Nox4 expression by small interfering RNA influenced the effect of PPARδ on MMP-2 activity, suggesting a mechanism in which Nox4-derived ROS modulates MMP-2 activity. Furthermore, c-Jun N-terminal kinase and p38, but not extracellular signal-regulated kinase, mediated PPARδ-dependent inhibition of MMP-2 activity in HGFs treated with Pg-LPS. Concomitantly, PPARδ-mediated inhibition of MMP-2 activity was associated with the restoration of types I and III collagen to levels approaching those in HGFs not treated with Pg-LPS. These results indicate that PPARδ-mediated downregulation of Nox4 modulates cellular redox status, which in turn plays a critical role in extracellular matrix homeostasis through ROS-dependent regulation of MMP-2 activity. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Swelling-induced optical anisotropy of thermoresponsive hydrogels based on poly(2-(2-methoxyethoxy)ethyl methacrylate): deswelling kinetics probed by quantitative Mueller matrix polarimetry.

    Science.gov (United States)

    Patil, Nagaraj; Soni, Jalpa; Ghosh, Nirmalya; De, Priyadarsi

    2012-11-29

    Thermodynamically favored polymer-water interactions below the lower critical solution temperature (LCST) caused swelling-induced optical anisotropy (linear retardance) of thermoresponsive hydrogels based on poly(2-(2-methoxyethoxy)ethyl methacrylate). This was exploited to study the macroscopic deswelling kinetics quantitatively by a generalized polarimetry analysis method, based on measurement of the Mueller matrix and its subsequent inverse analysis via the polar decomposition approach. The derived medium polarization parameters, namely, linear retardance (δ), diattenuation (d), and depolarization coefficient (Δ), of the hydrogels showed interesting differences between the gels prepared by conventional free radical polymerization (FRP) and reversible addition-fragmentation chain transfer polymerization (RAFT) and also between dry and swollen state. The effect of temperature, cross-linking density, and polymerization technique employed to synthesize hydrogel on deswelling kinetics was systematically studied via conventional gravimetry and corroborated further with the corresponding Mueller matrix derived quantitative polarimetry characteristics (δ, d, and Δ). The RAFT gels exhibited higher swelling ratio and swelling-induced optical anisotropy compared to FRP gels and also deswelled faster at 30 °C. On the contrary, at 45 °C, deswelling was significantly retarded for the RAFT gels due to formation of a skin layer, which was confirmed and quantified via the enhanced diattenuation and depolarization parameters.

  17. Lipid-soluble cigarette smoking particles induce expression of inflammatory and extracellular-matrix-related genes in rat cerebral arteries

    DEFF Research Database (Denmark)

    Vikman, Petter; Xu, Cang-Bao; Edvinsson, Lars

    2009-01-01

    AIMS: Cigarette smoking is one of the strongest risk factors for stroke. However, the underlying molecular mechanisms that smoke leads to the pathogenesis of stroke are incompletely understood. METHODS: Dimethyl sulfoxide (DMSO)-soluble (lipid-soluble) cigarette smoking particles (DSP) were...... extracted from cigarette smoke (0.8 mg nicotine per cigarette; Marlboro). Rat cerebral arteries were isolated and organ cultured in the presence of DSP (0.2 microl/ml, equivalent to the plasma level in smokers) for 24 h. The expression of matrix metalloproteinase 9 and 13 (MMP9 and MMP13), angiotensin...

  18. IL-1β-induced, matrix metalloproteinase-3-regulated proliferation of embryonic stem cell-derived odontoblastic cells is mediated by the Wnt5 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki; Kawai, Rie [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan)

    2014-10-15

    We previously established a method for differentiating induced pluripotent stem cells and embryonic stem (ES) cells into α2 integrin-positive odontoblast-like cells. We also reported that interleukin (IL)-1β induces matrix metalloproteinase (MMP)-3-regulated cell proliferation and suppresses apoptosis in these cells, suggesting that MMP-3 plays a potentially unique physiological role in the regeneration of odontoblast-like cells. Here, we examined whether up-regulation of MMP-3 activity by IL-1β was mediated by Wnt signaling and led to increased proliferation of odontoblast-like cells. IL-1β increased mRNA and protein levels of Wnt5a, Wnt5b and the Wnt receptor Lrp5. Exogenous Wnt5a and Wnt5b were found to increase MMP-3 mRNA, protein and activity, and interestingly the rate of proliferation in these cells. Treatment with siRNAs against Wnt5a, Wnt5b and Lrp5 suppressed the IL-1β-induced increase in MMP-3 expression and suppressed cell proliferation, an effect rescued by application of exogenous Wnt5. These results demonstrate the sequential involvement of Wnt5, Lrp5 and MMP-3 in effecting IL-1β-induced proliferation of ES cell-derived odontoblast-like cells. - Highlights: • IL-1β induces Wnt5, Lrp5/Fzd9 and MMP-3 in ES cell-derived odontoblast-like cells. • IL-1β-induced Wnt5 expression results in increased cell proliferation. • Exogenous Wnt5 increases MMP-3 activity and cell proliferation. • Exogenous Wnt5 rescues IL-1β-driven proliferation with anti-Wnt5 siRNA suppression. • IL-1β-induced cell proliferation involves Wnt5, Lrp5, and MMP-3 sequentially.

  19. IL-1β-induced, matrix metalloproteinase-3-regulated proliferation of embryonic stem cell-derived odontoblastic cells is mediated by the Wnt5 signaling pathway

    International Nuclear Information System (INIS)

    Ozeki, Nobuaki; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki; Kawai, Rie; Kondo, Ayami; Nakata, Kazuhiko; Mogi, Makio

    2014-01-01

    We previously established a method for differentiating induced pluripotent stem cells and embryonic stem (ES) cells into α2 integrin-positive odontoblast-like cells. We also reported that interleukin (IL)-1β induces matrix metalloproteinase (MMP)-3-regulated cell proliferation and suppresses apoptosis in these cells, suggesting that MMP-3 plays a potentially unique physiological role in the regeneration of odontoblast-like cells. Here, we examined whether up-regulation of MMP-3 activity by IL-1β was mediated by Wnt signaling and led to increased proliferation of odontoblast-like cells. IL-1β increased mRNA and protein levels of Wnt5a, Wnt5b and the Wnt receptor Lrp5. Exogenous Wnt5a and Wnt5b were found to increase MMP-3 mRNA, protein and activity, and interestingly the rate of proliferation in these cells. Treatment with siRNAs against Wnt5a, Wnt5b and Lrp5 suppressed the IL-1β-induced increase in MMP-3 expression and suppressed cell proliferation, an effect rescued by application of exogenous Wnt5. These results demonstrate the sequential involvement of Wnt5, Lrp5 and MMP-3 in effecting IL-1β-induced proliferation of ES cell-derived odontoblast-like cells. - Highlights: • IL-1β induces Wnt5, Lrp5/Fzd9 and MMP-3 in ES cell-derived odontoblast-like cells. • IL-1β-induced Wnt5 expression results in increased cell proliferation. • Exogenous Wnt5 increases MMP-3 activity and cell proliferation. • Exogenous Wnt5 rescues IL-1β-driven proliferation with anti-Wnt5 siRNA suppression. • IL-1β-induced cell proliferation involves Wnt5, Lrp5, and MMP-3 sequentially

  20. Sex ratio of the offspring of Sprague-Dawley rats exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in utero and lactationally in a three-generation study

    International Nuclear Information System (INIS)

    Rowlands, J.C.; Budinsky, R.A.; Aylward, L.L.; Faqi, A.S.; Carney, E.W.

    2006-01-01

    Reports of a decreased male/female sex ratio in children born to males exposed to TCDD in Seveso, Italy, at a young age have sparked examinations of this endpoint in other populations exposed to TCDD or related compounds. Overall, the male/female sex ratio results reported in these studies, with slightly different age-exposed male populations, have shown mixed results. Experimental studies of the effects of in utero exposure to TCDD in laboratory animals have reported no effect on the f 1 sex ratio and mixed results for the sex ratio of the f 2 generation. In order to better understand the potential effects of TCDD on second generation sex ratio, we retrieved archived data from a comprehensive three-generation feeding study of TCDD in rats that was conducted and published in the 1970s, but which did not publish data on sex ratio of the offspring [Murray, F.J., Smith, F.A., Nitschke, K.D., Humiston, C.G., Kociba, R.J., Schwetz, B.A., 1979. Three-generation reproduction study of rats given 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the diet. Toxicol. Appl. Pharmacol. 50, 241-252]. A re-examination of the original Murray et al. data found no statistically significant treatment-related changes in postnatal day 1 sex ratio in any generation of treated animals, consistent with one other relatively large study reporting on this endpoint. We discuss mechanistic data underlying a potential effect of TCDD on this endpoint. We conclude that the inconsistency in findings on sex ratio of the offspring of male rats exposed to TCDD in utero is likely due to random variation associated with a relatively small sample size, although differences between studies in strain of rat, dose regimen, and day of ascertainment of sex ratio cannot be ruled out

  1. Intracellular Wnt/Beta-Catenin Signaling Underlying 17beta-Estradiol-Induced Matrix Metalloproteinase 9 Expression in Human Endometriosis.

    Science.gov (United States)

    Zhang, Ling; Xiong, Wenqian; Xiong, Yao; Liu, Hengwei; Li, Na; Du, Yu; Liu, Yi

    2016-03-01

    Extracellular matrix remodeling is necessary for ectopic endometrium implantation. Many studies have shown an increased expression of matrix metalloproteinase 9 (MMP9) in the ectopic endometrium of endometriosis. However, the signaling pathways and cellular effects related to this process remain incompletely elucidated. The objective of our study was to investigate the association between MMP9 and the Wnt signaling pathway under the regulation of 17beta-estradiol (E2) in endometrial stromal cells. We found that MMP9 was elevated in tissues from women with endometriosis compared with normal women. Furthermore, MMP9 and beta-catenin increased concurrently in a time- and dose-dependent manner after E2 treatment. To clarify the relationship between MMP9 and beta-catenin, we performed luciferase promoter reporter and chromatin immunoprecipitation assays. A beta-catenin/TCF3/LEF1 complex bound to a specific site on the MMP9 promoter that promoted MMP9 gene and protein expression. The promotion of MMP9 by the Wnt signaling pathway under the regulation of E2 may contribute to the pathophysiology of this disease. © 2016 by the Society for the Study of Reproduction, Inc.

  2. Ethanol extract of Cordyceps militaris grown on germinated soybeans attenuates dextran-sodium-sulfate- (DSS-) induced colitis by suppressing the expression of matrix metalloproteinases and inflammatory mediators.

    Science.gov (United States)

    Park, Dong Ki; Park, Hye-Jin

    2013-01-01

    The effect of Cordyceps militaris (CM) grown on germinated soybeans (GSC) in the inflammatory bowel disease (IBD) model was studied. To demonstrate the preventive effect of GSC extract in a dextran-sodium-sulfate- (DSS-) induced acute colitis mouse model, GSC was administered 2 days before DSS coadministration. GSC significantly suppressed DSS-induced disease activity index (DAI) as well as histopathological scores, compared to control or CM-treated group. To elucidate the anti-IBD activity of GSC, we checked the level of matrix metalloproteinases (MMPs) and inflammatory mediators. GSC extract decreased the level of MMP-3 and -9 mRNAs and p53 proteins. The level and activity of LPS-induced MMP-9 were reduced in GSC-treated RAW264.7 cells. It also attenuated the level of inducible nitric oxide synthase (iNOS) and tumor necrosis factor- (TNF-) α mRNAs both in colon tissue and in macrophage cells. These results suggest that GSC can be applied as a protective agent against IBDs.

  3. Buddleja officinalis suppresses high glucose-induced vascular smooth muscle cell proliferation: role of mitogen-activated protein kinases, nuclear factor-kappaB and matrix metalloproteinases.

    Science.gov (United States)

    Lee, Yun Jung; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

    2010-02-01

    Diabetes mellitus is a well-established risk factor for vascular diseases caused by atherosclerosis. In the development of diabetic atherogenesis, vascular smooth muscle cell proliferation is recognized as a key event. Thus, we aimed to investigate whether an ethanol extract of Buddleja officinalis (EBO) suppresses high glucose-induced proliferation in primary cultured human aortic smooth muscle cells (HASMC). [(3)H]-thymidine incorporation revealed that incubation of HASMC with a high concentration of glucose (25 mmol/L) increased cell proliferation. The expression levels of cell cycle protein were also increased by treatment with high glucose concentration. Pretreatment of HASMC with EBO significantly attenuated the increase of high glucose-induced cell proliferation as well as p38 mitogen-activated protein kinases (MAPK) and JNK phosphorylation. EBO suppressed high glucose-induced matrix metalloproteinase (MMP)-9 activity in a dose-dependent manner. In addition, EBO suppressed nuclear factor-kappaB (NF-kappaB) nuclear translocation and transcriptional activity in high glucose conditions. Taken together, the present data suggest that EBO could suppress high glucose-induced atherosclerotic processes through inhibition of p38, JNK, NF-kappaB and MMP signal pathways in HASMC.

  4. Defining suitable reference genes for RT-qPCR analysis on human sertoli cells after 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure.

    Science.gov (United States)

    Ribeiro, Mariana Antunes; dos Reis, Mariana Bisarro; de Moraes, Leonardo Nazário; Briton-Jones, Christine; Rainho, Cláudia Aparecida; Scarano, Wellerson Rodrigo

    2014-11-01

    Quantitative real-time RT-PCR (qPCR) has proven to be a valuable molecular technique to quantify gene expression. There are few studies in the literature that describe suitable reference genes to normalize gene expression data. Studies of transcriptionally disruptive toxins, like tetrachlorodibenzo-p-dioxin (TCDD), require careful consideration of reference genes. The present study was designed to validate potential reference genes in human Sertoli cells after exposure to TCDD. 32 candidate reference genes were analyzed to determine their applicability. geNorm and NormFinder softwares were used to obtain an estimation of the expression stability of the 32 genes and to identify the most suitable genes for qPCR data normalization.

  5. Influence of vaginal bacteria and D- and L-lactic acid isomers on vaginal extracellular matrix metalloproteinase inducer: implications for protection against upper genital tract infections.

    Science.gov (United States)

    Witkin, Steven S; Mendes-Soares, Helena; Linhares, Iara M; Jayaram, Aswathi; Ledger, William J; Forney, Larry J

    2013-08-06

    We evaluated levels of vaginal extracellular matrix metalloproteinase inducer (EMMPRIN) and matrix metalloproteinase (MMP-8) in vaginal secretions in relation to the composition of vaginal bacterial communities and D- and L-lactic acid levels. The composition of vaginal bacterial communities in 46 women was determined by pyrosequencing the V1 to V3 region of 16S rRNA genes. Lactobacilli were dominant in 71.3% of the women, followed by Gardnerella (17.4%), Streptococcus (8.7%), and Enterococcus (2.2%). Of the lactobacillus-dominated communities, 51.5% were dominated by Lactobacillus crispatus, 36.4% by Lactobacillus iners, and 6.1% each by Lactobacillus gasseri and Lactobacillus jensenii. Concentrations of L-lactic acid were slightly higher in lactobacillus-dominated vaginal samples, but most differences were not statistically significant. D-Lactic acid levels were higher in samples containing L. crispatus than in those with L. iners (Plactic acid in vaginal communities dominated by species of lactobacilli was in concordance with the proportions found in axenic cultures of the various species grown in vitro. Levels of L-lactic acid (Plactic acid to D-lactic acid (P=0.0060), but not concentrations of D-lactic acid, were also correlated with EMMPRIN concentrations. Moreover, vaginal concentrations of EMMPRIN and MMP-8 levels were highly correlated (Plactic acid isomers in the vagina may influence the extent of local EMMPRIN production and subsequent induction of MMP-8. The expression of these proteins may help determine the ability of bacteria to transverse the cervix and initiate upper genital tract infections. A large proportion of preterm births (>50%) result from infections caused by bacteria originating in the vagina, which requires that they traverse the cervix. Factors that influence susceptibility to these infections are not well understood; however, there is evidence that matrix metalloproteinase (MMP-8) is known to alter the integrity of the cervix. In this

  6. Mast cell-restricted, tetramer-forming tryptases induce aggrecanolysis in articular cartilage by activating matrix metalloproteinase-3 and -13 zymogens.

    Science.gov (United States)

    Magarinos, Natalia J; Bryant, Katherine J; Fosang, Amanda J; Adachi, Roberto; Stevens, Richard L; McNeil, H Patrick

    2013-08-01

    Mouse mast cell protease (mMCP)-6-null C57BL/6 mice lost less aggrecan proteoglycan from the extracellular matrix of their articular cartilage during inflammatory arthritis than wild-type (WT) C57BL/6 mice, suggesting that this mast cell (MC)-specific mouse tryptase plays prominent roles in articular cartilage catabolism. We used ex vivo mouse femoral head explants to determine how mMCP-6 and its human ortholog hTryptase-β mediate aggrecanolysis. Exposure of the explants to recombinant hTryptase-β, recombinant mMCP-6, or lysates harvested from WT mouse peritoneal MCs (PMCs) significantly increased the levels of enzymatically active matrix metalloproteinases (MMP) in cartilage and significantly induced aggrecan loss into the conditioned media, relative to replicate explants exposed to medium alone or lysates collected from mMCP-6-null PMCs. Treatment of cartilage explants with tetramer-forming tryptases generated aggrecan fragments that contained C-terminal DIPEN and N-terminal FFGVG neoepitopes, consistent with MMP-dependent aggrecanolysis. In support of these data, hTryptase-β was unable to induce aggrecan release from the femoral head explants obtained from Chloe mice that resist MMP cleavage at the DIPEN↓FFGVG site in the interglobular domain of aggrecan. In addition, the abilities of mMCP-6-containing lysates from WT PMCs to induce aggrecanolysis were prevented by inhibitors of MMP-3 and MMP-13. Finally, recombinant hTryptase-β was able to activate latent pro-MMP-3 and pro-MMP-13 in vitro. The accumulated data suggest that human and mouse tetramer-forming tryptases are MMP convertases that mediate cartilage damage and the proteolytic loss of aggrecan proteoglycans in arthritis, in part, by activating the zymogen forms of MMP-3 and MMP-13, which are constitutively present in articular cartilage.

  7. IL-1β-induced matrix metalloproteinase-13 is activated by a disintegrin and metalloprotease-28-regulated proliferation of human osteoblast-like cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Kawai, Rie; Yamaguchi, Hideyuki; Hiyama, Taiki; Kinoshita, Katsue; Hase, Naoko; Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya, Aichi 464-8650 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya, Aichi 464-8650 (Japan); Nakamura, Hiroshi [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan)

    2014-04-15

    We reported previously that matrix metalloproteinase (MMP)-13 accelerates bone remodeling in oral periradicular lesions, and indicated a potentially unique role for MMP-13 in wound healing and regeneration of alveolar bone. The ADAM (a disintegrin and metalloprotease) family is a set of multifunctional cell surface and secreted glycoproteins, of which ADAM-28 has been localized in bone and bone-like tissues. In this study, we show that interleukin (IL)-1β induces the expression of MMP-13 and ADAM-28 in homogeneous α7 integrin-positive human skeletal muscle stem cell (α7{sup +}hSMSC)-derived osteoblast-like (α7{sup +}hSMSC-OB) cells, and promotes proliferation while inhibiting apoptosis in these cells. At higher concentrations, however, IL-1β failed to induce the expression of these genes and caused an increase in apoptosis. We further employed ADAM-28 small interfering RNA (siRNA) to investigate whether IL-1β-induced MMP-13 expression is linked to this IL-1β-mediated changes in cell proliferation and apoptosis. Silencing ADAM-28 expression potently suppressed IL-1β-induced MMP-13 expression and activity, decreased cell proliferation and increased apoptosis in α7{sup +}hSMSC-OB cells. In contrast, MMP-13 siRNA had no effect on ADAM-28 expression, suggesting ADAM-28 regulates MMP-13. Exogenous MMP-13 induced α7{sup +}hSMSC-OB cell proliferation and could rescue ADAM-28 siRNA-induced apoptosis, and we found that proMMP-13 is partially cleaved into its active form by ADAM-28 in vitro. Overall, our results suggest that IL-1β-induced MMP-13 expression and changes in cell proliferation and apoptosis in α7{sup +}hSMSC-OB cells are regulated by ADAM-28. - Highlights: • IL-1β induces the MMP-13 and ADAM-28 expression in human osteoblast-like cells. • IL-1β-induced MMP-13 expression increases proliferation and decreased apoptosis. • MMP-13 expression induced by IL-1β is regulated by ADAM-28. • proMMP-13 appears to be cleaved into its active form via

  8. IL-1β-induced matrix metalloproteinase-13 is activated by a disintegrin and metalloprotease-28-regulated proliferation of human osteoblast-like cells

    International Nuclear Information System (INIS)

    Ozeki, Nobuaki; Kawai, Rie; Yamaguchi, Hideyuki; Hiyama, Taiki; Kinoshita, Katsue; Hase, Naoko; Nakata, Kazuhiko; Kondo, Ayami; Mogi, Makio; Nakamura, Hiroshi

    2014-01-01

    We reported previously that matrix metalloproteinase (MMP)-13 accelerates bone remodeling in oral periradicular lesions, and indicated a potentially unique role for MMP-13 in wound healing and regeneration of alveolar bone. The ADAM (a disintegrin and metalloprotease) family is a set of multifunctional cell surface and secreted glycoproteins, of which ADAM-28 has been localized in bone and bone-like tissues. In this study, we show that interleukin (IL)-1β induces the expression of MMP-13 and ADAM-28 in homogeneous α7 integrin-positive human skeletal muscle stem cell (α7 + hSMSC)-derived osteoblast-like (α7 + hSMSC-OB) cells, and promotes proliferation while inhibiting apoptosis in these cells. At higher concentrations, however, IL-1β failed to induce the expression of these genes and caused an increase in apoptosis. We further employed ADAM-28 small interfering RNA (siRNA) to investigate whether IL-1β-induced MMP-13 expression is linked to this IL-1β-mediated changes in cell proliferation and apoptosis. Silencing ADAM-28 expression potently suppressed IL-1β-induced MMP-13 expression and activity, decreased cell proliferation and increased apoptosis in α7 + hSMSC-OB cells. In contrast, MMP-13 siRNA had no effect on ADAM-28 expression, suggesting ADAM-28 regulates MMP-13. Exogenous MMP-13 induced α7 + hSMSC-OB cell proliferation and could rescue ADAM-28 siRNA-induced apoptosis, and we found that proMMP-13 is partially cleaved into its active form by ADAM-28 in vitro. Overall, our results suggest that IL-1β-induced MMP-13 expression and changes in cell proliferation and apoptosis in α7 + hSMSC-OB cells are regulated by ADAM-28. - Highlights: • IL-1β induces the MMP-13 and ADAM-28 expression in human osteoblast-like cells. • IL-1β-induced MMP-13 expression increases proliferation and decreased apoptosis. • MMP-13 expression induced by IL-1β is regulated by ADAM-28. • proMMP-13 appears to be cleaved into its active form via ADAM-28

  9. TNF-{alpha} promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Cheng-hu; Cao, Guo-Fan [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Jiang, Qin, E-mail: Jqin710@vip.sina.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China); Yao, Jin, E-mail: dryaojin@yahoo.com [The Affiliated Eye Hospital of Nanjing Medical University, Nanjing 210029 (China)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer TNF-{alpha} induces MMP-9 expression and secretion to promote RPE cell migration. Black-Right-Pointing-Pointer MAPK activation is not critical for TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer Akt and mTORC1 signaling mediate TNF-{alpha}-induced MMP-9 expression. Black-Right-Pointing-Pointer SIN1 knockdown showed no significant effect on MMP-9 expression by TNF-{alpha}. -- Abstract: Tumor necrosis factor-alpha (TNF-{alpha}) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-{alpha} promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-{alpha}-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-{alpha}-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-{alpha} promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.

  10. TNF-α promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

    International Nuclear Information System (INIS)

    Wang, Cheng-hu; Cao, Guo-Fan; Jiang, Qin; Yao, Jin

    2012-01-01

    Highlights: ► TNF-α induces MMP-9 expression and secretion to promote RPE cell migration. ► MAPK activation is not critical for TNF-α-induced MMP-9 expression. ► Akt and mTORC1 signaling mediate TNF-α-induced MMP-9 expression. ► SIN1 knockdown showed no significant effect on MMP-9 expression by TNF-α. -- Abstract: Tumor necrosis factor-alpha (TNF-α) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-α promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-α-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-α-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-α promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.

  11. Matrix cross-linking lysyl oxidases are induced in response to myocardial infarction and promote cardiac dysfunction

    DEFF Research Database (Denmark)

    González-Santamaría, José; Villalba, María; Busnadiego, Oscar

    2016-01-01

    resulted in reduced ventricular dilatation and improved cardiac function. CONCLUSION: LOX family members contribute significantly to the detrimental effects of cardiac remodelling, highlighting LOX inhibition as a potential therapeutic strategy for post-infarction recovery....... contributed to the induction of LOX expression in cardiac fibroblasts. Finally, in vivo post-infarction treatment with the broadband LOX inhibitor β-aminopropionitrile or, selectively, with a neutralizing antibody against the canonical LOX isoform attenuated collagen accumulation and maturation and also......AIMS: After myocardial infarction (MI), extensive remodelling of the extracellular matrix contributes to scar formation. While aiming to preserve tissue integrity, this fibrotic response is also associated with adverse events, including a markedly increased risk of heart failure, ventricular...

  12. Role of the inducible adhesin, CpAls7, in binding ofCandida parapsilosisto extracellular matrix under fluid shear.

    Science.gov (United States)

    Neale, Matthew N; Glass, Kyle A; Longley, Sarah J; Kim, Denny J; Laforce-Nesbitt, Sonia S; Wortzel, Jeremy D; Shaw, Sunil K; Bliss, Joseph M

    2018-01-29

    The yeast, Candida parapsilosis , is an increasingly common cause of systemic fungal infections among the immune compromised, including premature infants. Adhesion to host surfaces is an important step in pathogenesis, but this process has not been extensively studied in this organism. A microfluidics assay was developed to test the ability of C. parapsilosis to adhere to immobilized host extracellular matrix proteins under physiologic fluid shear conditions. Growth in mammalian tissue culture media at 37°C for 3-6 hours led to induction of an adhesive phenotype at shear forces of 1-5 dynes/cm 2 in some isolates of C. parapsilosis Glutamic acid, proline and calcium appeared to be the minimally necessary requirements for increased adhesion in these assays. To determine whether genes homologous to the ALS gene family of C. albicans were important for the adhesive phenotype, expression of 5 homologous C. parapsilosis genes were quantified using qPCR under conditions leading to increased adhesion. CPAR2_404800 ( CpALS7 ) and CPAR2_404780 showed increased expression compared to control yeast. The extent of adhesion was variable among different isolates, and linear regression identified expression of CpALS7 but not CPAR2_404780 to have a strong positive correlation with adhesion. A homozygous CpALS7 deletion strain was deficient in adhesion, whereas expression of CpALS7 in S. cerevisiae resulted in increased adhesion. Together, these data provide strong evidence that CpAls7 aids in the adherence of C. parapsilosis to extracellular matrix under shear forces and support its previously reported role in virulence. Copyright © 2018 American Society for Microbiology.

  13. Studies on the metabolic fate of [14C]2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the mouse

    International Nuclear Information System (INIS)

    Koshakji, R.P.; Harbison, R.D.; Bush, M.T.

    1984-01-01

    After a single po dose (135 micrograms/kg; 62 microCi/kg) of 14 C-labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in male ICR/Ha Swiss mice, 67 to 76% of the administered dose was eliminated via the feces and 1 to 2% in the urine during the first 24 hr following treatment. It seems likely that most of this material was simply not absorbed. Much of the remaining chemical was then excreted slowly in the urine (2%) and feces (7%) during the next 10 days, partly as the unchanged compound and partly as metabolites. One of the metabolites (Fraction II) appears to be a single polar, acidic metabolite characterized in urine (0.4 +/- 0.1%) and feces (2.2 +/- 0.2%), and is also likely excreted as a glucuronide conjugate. The rest of the radioactivity was in the form of unchanged TCDD in the animal body (17 +/- 2%). Steady rates of decline in the concentrations of the 14 C as well as of the unchanged TCDD were reached in the feces and urine after the fifth day following the administration of the chemical. Based on this steady rate, the half-life of the radioactivity in the body was approximately 20 days. Urine, feces, and whole body were analyzed by solvent extraction, 14 C counting, thin-layer chromatography, and countercurrent distribution

  14. Differences in TCDD-elicited gene expression profiles in human HepG2, mouse Hepa1c1c7 and rat H4IIE hepatoma cells

    Directory of Open Access Journals (Sweden)

    Burgoon Lyle D

    2011-04-01

    Full Text Available Abstract Background 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD is an environmental contaminant that elicits a broad spectrum of toxic effects in a species-specific manner. Current risk assessment practices routinely extrapolate results from in vivo and in vitro rodent models to assess human risk. In order to further investigate the species-specific responses elicited by TCDD, temporal gene expression responses in human HepG2, mouse Hepa1c1c7 and rat H4IIE cells were compared. Results Microarray analysis identified a core set of conserved gene expression responses across species consistent with the role of AhR in mediating adaptive metabolic responses. However, significant species-specific as well as species-divergent responses were identified. Computational analysis of the regulatory regions of species-specific and -divergent responses suggests that dioxin response elements (DREs are involved. These results are consistent with in vivo rat vs. mouse species-specific differential gene expression, and more comprehensive comparative DRE searches. Conclusions Comparative analysis of human HepG2, mouse Hepa1c1c7 and rat H4IIE TCDD-elicited gene expression responses is consistent with in vivo rat-mouse comparative gene expression studies, and more comprehensive comparative DRE searches, suggesting that AhR-mediated gene expression is species-specific.

  15. Transdermal delivery of insulin by amidated pectin hydrogel matrix patch in streptozotocin-induced diabetic rats: effects on some selected metabolic parameters.

    Directory of Open Access Journals (Sweden)

    Silindile I Hadebe

    Full Text Available Studies in our laboratory are concerned with developing optional insulin delivery routes based on amidated pectin hydrogel matrix gel. We therefore investigated whether the application of pectin insulin (PI-containing dermal patches of different insulin concentrations sustain controlled release of insulin into the bloodstream of streptozotocin (STZ-induced diabetic rats with concomitant alleviation of diabetic symptoms in target tissues, most importantly, muscle and liver.Oral glucose test (OGT responses to PI dermal matrix patches (2.47, 3.99, 9.57, 16.80 µg/kg prepared by dissolving pectin/insulin in deionised water and solidified with CaCl2 were monitored in diabetic rats given a glucose load after an 18-h fast. Short-term (5 weeks metabolic effects were assessed in animals treated thrice daily with PI patches 8 hours apart. Animals treated with drug-free pectin and insulin (175 µg/kg, s.c. acted as untreated and treated positive controls, respectively. Blood, muscle and liver samples were collected for measurements of selected biochemical parameters.After 5 weeks, untreated diabetic rats exhibited hyperglycaemia and depleted hepatic and muscle glycogen concentrations. Compared to untreated STZ-induced diabetic animals, OGT responses of diabetic rats transdermally applied PI patches exhibited lower blood glucose levels whilst short-term treatments restored hepatic and muscle glycogen concentrations. Plasma insulin concentrations of untreated diabetic rats were low compared with control non-diabetic rats. All PI treatments elevated plasma insulin concentrations of diabetic rats although the levels induced by high doses (9.57 and 16.80 µg/kg were greater than those caused by low doses (2.47 and 3.99 µg/kg but comparable to those in sc insulin treated animals.The data suggest that the PI hydrogel matrix patch can deliver physiologically relevant amounts of pharmacologically active insulin.A new method to administer insulin into the

  16. Transdermal Delivery of Insulin by Amidated Pectin Hydrogel Matrix Patch in Streptozotocin-Induced Diabetic Rats: Effects on Some Selected Metabolic Parameters

    Science.gov (United States)

    Hadebe, Silindile I.; Ngubane, Phikelelani S.; Serumula, Metse R.; Musabayane, Cephas T.

    2014-01-01

    Purpose Studies in our laboratory are concerned with developing optional insulin delivery routes based on amidated pectin hydrogel matrix gel. We therefore investigated whether the application of pectin insulin (PI)-containing dermal patches of different insulin concentrations sustain controlled release of insulin into the bloodstream of streptozotocin (STZ)-induced diabetic rats with concomitant alleviation of diabetic symptoms in target tissues, most importantly, muscle and liver. Methods Oral glucose test (OGT) responses to PI dermal matrix patches (2.47, 3.99, 9.57, 16.80 µg/kg) prepared by dissolving pectin/insulin in deionised water and solidified with CaCl2 were monitored in diabetic rats given a glucose load after an 18-h fast. Short-term (5 weeks) metabolic effects were assessed in animals treated thrice daily with PI patches 8 hours apart. Animals treated with drug-free pectin and insulin (175 µg/kg, sc) acted as untreated and treated positive controls, respectively. Blood, muscle and liver samples were collected for measurements of selected biochemical parameters. Results After 5 weeks, untreated diabetic rats exhibited hyperglycaemia and depleted hepatic and muscle glycogen concentrations. Compared to untreated STZ-induced diabetic animals, OGT responses of diabetic rats transdermally applied PI patches exhibited lower blood glucose levels whilst short-term treatments restored hepatic and muscle glycogen concentrations. Plasma insulin concentrations of untreated diabetic rats were low compared with control non-diabetic rats. All PI treatments elevated plasma insulin concentrations of diabetic rats although the levels induced by high doses (9.57 and 16.80 µg/kg) were greater than those caused by low doses (2.47 and 3.99 µg/kg) but comparable to those in sc insulin treated animals. Conclusions The data suggest that the PI hydrogel matrix patch can deliver physiologically relevant amounts of pharmacologically active insulin. Novelty of the Work A new

  17. Sulforaphane inhibits CYP1A1 activity and promotes genotoxicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Fangxing, E-mail: fxyang@zju.edu.cn [MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058 (China); Zhuang, Shulin [MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058 (China); Zhang, Chao; Dai, Heping [State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072 (China); Liu, Weiping, E-mail: wliu@zju.edu.cn [MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058 (China)

    2013-06-15

    Increasing environmental pollution by carcinogens such as some of persistent organic pollutants (POPs) has prompted growing interest in searching for chemopreventive compounds which are readily obtainable. Sulforaphane (SFN) is isolated from cruciferous vegetables and has the potentials to reduce carcinogenesis through various pathways. In this study, we studied the effects of SFN on CYP1A1 activity and genotoxicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The results showed that SFN inhibited TCDD-induced CYP1A1 activity in H4IIE cells by directly inhibiting CYP1A1 activity, probably through binding to aryl hydrocarbon receptor and/or CYP1A1 revealed by molecular docking. However, SFN promoted TCDD-induced DNA damage in yeast cells and reduced the viability of initiated yeast cells. Besides, it is surprising that SFN also failed to reduce genotoxicity induced by other genotoxic reagents which possess different mechanisms to lead to DNA damage. Currently, it is difficult to predict whether SFN has the potentials to reduce the risk of TCDD based on the conflicting observations in the study. Therefore, further studies should be urgent to reveal the function and mechanism of SFN in the stress of such POPs on human health. - Highlights: • Sulforaphane inhibited TCDD-induced CYP1A1 activity in H4IIE cells. • Sulforaphane may bind to aryl hydrocarbon receptor and/or CYP1A1. • Sulforaphane promoted TCDD-induced DNA damage in yeast cells. • Sulforaphane may promote DNA damage by DNA strand breaks or DNA alkylation.

  18. Lipid rafts regulate PCB153-induced disruption of occludin and brain endothelial barrier function through protein phosphatase 2A and matrix metalloproteinase-2

    Energy Technology Data Exchange (ETDEWEB)

    Eum, Sung Yong, E-mail: seum@miami.edu; Jaraki, Dima; András, Ibolya E.; Toborek, Michal

    2015-09-15

    Occludin is an essential integral transmembrane protein regulating tight junction (TJ) integrity in brain endothelial cells. Phosphorylation of occludin is associated with its localization to TJ sites and incorporation into intact TJ assembly. The present study is focused on the role of lipid rafts in polychlorinated biphenyl (PCB)-induced disruption of occludin and endothelial barrier function. Exposure of human brain endothelial cells to 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB153) induced dephosphorylation of threonine residues of occludin and displacement of occludin from detergent-resistant membrane (DRM)/lipid raft fractions within 1 h. Moreover, lipid rafts modulated the reduction of occludin level through activation of matrix metalloproteinase 2 (MMP-2) after 24 h PCB153 treatment. Inhibition of protein phosphatase 2A (PP2A) activity by okadaic acid or fostriecin markedly protected against PCB153-induced displacement of occludin and increased permeability of endothelial cells. The implication of lipid rafts and PP2A signaling in these processes was further defined by co-immunoprecipitation of occludin with PP2A and caveolin-1, a marker protein of lipid rafts. Indeed, a significant MMP-2 activity was observed in lipid rafts and was increased by exposure to PCB153. The pretreatment of MMP-2 inhibitors protected against PCB153-induced loss of occludin and disruption of lipid raft structure prevented the increase of endothelial permeability. Overall, these results indicate that lipid raft-associated processes, such as PP2A and MMP-2 activation, participate in PCB153-induced disruption of occludin function in brain endothelial barrier. This study contributes to a better understanding of the mechanisms leading to brain endothelial barrier dysfunction in response to exposure to environmental pollutants, such as ortho-substituted PCBs. - Highlights: • PCB153 disturbed human brain endothelial barrier through disruption of occludin. • Lipid raft-associated PP

  19. Nanoscale characterization of the evolution of the twin–matrix orientation in Fe–Mn–C twinning-induced plasticity steel by means of transmission electron microscopy orientation mapping

    International Nuclear Information System (INIS)

    Albou, A.; Galceran, M.; Renard, K.; Godet, S.; Jacques, P.J.

    2013-01-01

    The evolution of the orientation relationship between mechanical twins and the surrounding matrix with the degree of plastic deformation has been characterized at the nanoscale in twinning-induced plasticity steel. The recently developed automated crystal orientation mapping in transmission electron microscopy revealed that the ideal twin relationship is retained up to large levels of strain, while large orientation gradients are built up within the matrix. This particular evolution undoubtedly plays a role in the large work hardening rate of these steels.

  20. Matrix calculus

    CERN Document Server

    Bodewig, E

    1959-01-01

    Matrix Calculus, Second Revised and Enlarged Edition focuses on systematic calculation with the building blocks of a matrix and rows and columns, shunning the use of individual elements. The publication first offers information on vectors, matrices, further applications, measures of the magnitude of a matrix, and forms. The text then examines eigenvalues and exact solutions, including the characteristic equation, eigenrows, extremum properties of the eigenvalues, bounds for the eigenvalues, elementary divisors, and bounds for the determinant. The text ponders on approximate solutions, as well

  1. Effects of rosuvastatin on the production and activation of matrix metalloproteinase-2 and migration of cultured rat vascular smooth muscle cells induced by homocysteine*

    Science.gov (United States)

    Shi, Ya-fei; Chi, Ju-fang; Tang, Wei-liang; Xu, Fu-kang; Liu, Long-bin; Ji, Zheng; Lv, Hai-tao; Guo, Hang-yuan

    2013-01-01

    Objective: To test the influence of homocysteine on the production and activation of matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of matrix metalloproteinase-2 (TIMP-2) and on cell migration of cultured rat vascular smooth muscle cells (VSMCs). Also, to explore whether rosuvastatin can alter the abnormal secretion and activation of MMP-2 and TIMP-2 and migration of VSMCs induced by homocysteine. Methods: Rat VSMCs were incubated with different concentrations of homocysteine (50–5 000 μmol/L). Western blotting and gelatin zymography were used to investigate the expressions and activities of MMP-2 and TIMP-2 in VSMCs in culture medium when induced with homocysteine for 24, 48, and 72 h. Transwell chambers were employed to test the migratory ability of VSMCs when incubated with homocysteine for 48 h. Different concentrations of rosuvastatin (10−9–10−5 mol/L) were added when VSMCs were induced with 1 000 μmol/L homocysteine. The expressions and activities of MMP-2 and TIMP-2 were examined after incubating for 24, 48, and 72 h, and the migration of VSMCs was also examined after incubating for 48 h. Results: Homocysteine (50–1 000 μmol/L) increased the production and activation of MMP-2 and expression of TIMP-2 in a dose-dependent manner. However, when incubated with 5 000 μmol/L homocysteine, the expression of MMP-2 was up-regulated, but its activity was down-regulated. Increased homocysteine-induced production and activation of MMP-2 were reduced by rosuvastatin in a dose-dependent manner whereas secretion of TIMP-2 was not significantly altered by rosuvastatin. Homocysteine (50–5 000 μmol/L) stimulated the migration of VSMCs in a dose-dependent manner, but this effect was eliminated by rosuvastatin. Conclusions: Homocysteine (50–1 000 μmol/L) significantly increased the production and activation of MMP-2, the expression of TIMP-2, and the migration of VSMCs in a dose-dependent manner. Additional extracellular rosuvastatin can decrease

  2. Lipid-soluble cigarette smoking particles induce expression of inflammatory and extracellular-matrix-related genes in rat cerebral arteries

    DEFF Research Database (Denmark)

    Vikman, Petter; Xu, Cang-Bao; Edvinsson, Lars

    2009-01-01

    levels, suggesting that a transcriptional mechanism is most likely involved in the DSP effects. This is further supported by the findings that DSP induced phosphorylation of p38 mitogen-activated protein kinases inflammatory signal protein in parallel with activation of its downstream transcription...

  3. Hydrogel is Superior to Fibrin Gel as Matrix of Stem Cells in Alleviating Antigen-Induced Arthritis

    Directory of Open Access Journals (Sweden)

    He Liu

    2016-05-01

    Full Text Available Recently, therapy with bone marrow mesenchymal stem cells (BMMSCs has been attempted to relieve rheumatoid arthritis (RA and reconstruct cartilage injury. However, treatment has been unsuccessful in complete prevention of persistent cartilage destruction and resulted in inferior outcomes of cartilage regeneration. Scaffolds are an important construct in the field of cartilage tissue engineering, but their role in arthritis treatment has not yet been fully examined. Here, we transplanted two types of scaffold-assisted BMMSCs: fibrin gel- and poly(l-lactide-co-glycolide−poly(ethylene glycol−poly(l-lactide-co-glycolide (PLGA−PEG−PLGA hydrogel-assisted BMMSCs referred as FGB and HGB groups, respectively, into subchondral defects for the treatment of antigen-induced arthritis. The administration of exogenous BMMSCs ameliorated joint swelling and decreased both joint surface temperature and inflammatory cytokine levels in both groups. Immune cell composition of the inflammation of surrounding synovium, protection of adjacent cartilage, and improved cartilage repair were also observed. Overall, the HGB group had a better therapeutic efficacy than the FGB group. In conclusion, local transplantation of BMMSCs in subchondral defects presents a novel approach in inducing RA remission and recovery of RA-induced cartilage injury. To induce these changes, the selection of scaffold for cell support is exceedingly important. Further studies are needed regarding the treatment options of subchondral defects in arthritis based on modified scaffold development, application of defined MSCs sources, combination of pharmacotherapeutics, and the addition of factors that inhibit the processes of RA remission, promote the recovery of RA-induced cartilage injury and the relationship between these factors.

  4. Wnt16 Signaling Is Required for IL-1β-Induced Matrix Metalloproteinase-13-Regulated Proliferation of Human Stem Cell-Derived Osteoblastic Cells.

    Science.gov (United States)

    Ozeki, Nobuaki; Mogi, Makio; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki; Kawai, Rie; Kondo, Ayami; Nakata, Kazuhiko

    2016-02-06

    We established a differentiation method for homogeneous α7 integrin-positive human skeletal muscle stem cell (α7⁺hSMSC)-derived osteoblast-like (α7⁺hSMSC-OB) cells, and found that interleukin (IL)-1β induces matrix metalloproteinase (MMP)-13-regulated proliferation of these cells. These data suggest that MMP-13 plays a potentially unique physiological role in the regeneration of osteoblast-like cells. Here, we examined whether up-regulation of MMP-13 activity by IL-1β was mediated by Wingless/int1 (Wnt) signaling and increased the proliferation of osteoblast-like cells. IL-1β increased the mRNA and protein levels of Wnt16 and the Wnt receptor Lrp5/Fzd2. Exogenous Wnt16 was found to increase MMP-13 mRNA, protein and activity, and interestingly, the proliferation rate of these cells. Treatment with small interfering RNAs against Wnt16 and Lrp5 suppressed the IL-1β-induced increase in cell proliferation. We revealed that a unique signaling cascade IL-1β→Wnt16→Lrp5→MMP-13, was intimately involved in the proliferation of osteoblast-like cells, and suggest that IL-1β-induced MMP-13 expression and changes in cell proliferation are regulated by Wnt16.

  5. Recovery of extracellular matrix components by enalapril maleate during the repair process of ultraviolet B-induced wrinkles in mouse skin.

    Science.gov (United States)

    Matsuura-Hachiya, Yuko; Nakai, Yuji; Abe, Keiko; Nishiyama, Toshio; Arai, Koji Y

    2015-12-01

    The renin-angiotensin system is known to be involved in skin remodeling and inflammation. Previously, we reported that ultraviolet B (UVB) irradiation enhanced angiotensin-converting enzyme (ACE) expression and angiotensin II levels in hairless mouse skin, and an ACE inhibitor, enalapril maleate (EM), accelerated repair of UVB-induced wrinkles. In this study, we analyzed gene expression profiles by DNA microarray and protein distribution patterns using an immunofluorescence method to clarify the process of EM-accelerated wrinkle repair in UVB-irradiated hairless mouse skin. In the microarray analysis, we detected EM-induced up-regulation of various extracellular matrix (ECM)-related genes in the UVB-irradiated skin. In the immunofluorescence, we confirmed that type I collagen α1 chain, fibrillin 1, elastin and dystroglycan 1 in the skin decreased after repeated UVB irradiation but staining for these proteins was improved by EM treatment. In addition, ADAMTS2 and MMP-14 also increased in the EM-treated skin. Although the relationship between these molecules and wrinkle formation is not clear yet, our present data suggest that the molecules are involved in the repair of UVB-induced wrinkles.

  6. The Effector Protein BPE005 from Brucella abortus Induces Collagen Deposition and Matrix Metalloproteinase 9 Downmodulation via Transforming Growth Factor β1 in Hepatic Stellate Cells.

    Science.gov (United States)

    Arriola Benitez, Paula Constanza; Rey Serantes, Diego; Herrmann, Claudia Karina; Pesce Viglietti, Ayelén Ivana; Vanzulli, Silvia; Giambartolomei, Guillermo Hernán; Comerci, Diego José; Delpino, María Victoria

    2016-02-01

    The liver is frequently affected in patients with active brucellosis. In the present study, we identified a virulence factor involved in the modulation of hepatic stellate cell function and consequent fibrosis during Brucella abortus infection. This study assessed the role of BPE005 protein from B. abortus in the fibrotic phenotype induced on hepatic stellate cells during B. abortus infection in vitro and in vivo. We demonstrated that the fibrotic phenotype induced by B. abortus on hepatic stellate (LX-2) cells was dependent on BPE005, a protein associated with the type IV secretion system (T4SS) VirB from B. abortus. Our results indicated that B. abortus inhibits matrix metalloproteinase 9 (MMP-9) secretion through the activity of the BPE005-secreted protein and induces concomitant collagen deposition by LX-2 cells. BPE005 is a small protein containing a cyclic nucleotide monophosphate binding domain (cNMP) that modulates the LX-2 cell phenotype through a mechanism that is dependent on the cyclic AMP (cAMP)/protein kinase A (PKA) signaling pathway. Altogether, these results indicate that B. abortus tilts LX-2 cells to a profibrogenic phenotype employing a functional T4SS and the secreted BPE005 protein through a mechanism that involves the cAMP and PKA signaling pathway. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  7. Protective Effects of LSGYGP from Fish Skin Gelatin Hydrolysates on UVB-Induced MEFs by Regulation of Oxidative Stress and Matrix Metalloproteinase Activity

    Directory of Open Access Journals (Sweden)

    Qingyu Ma

    2018-03-01

    Full Text Available A previous study has shown that tilapia fish skin gelatin hydrolysates inhibited photoaging in vivo, and that, Leu-Ser-Gly-Tyr-Gly-Pro (LSGYGP identified in the hydrolysate had a high hydroxyl radical scavenging activity. In this study, activities of LSGYGP were further evaluated using ultraviolet B (UVB-induced mouse embryonic fibroblasts (MEFs. UVB irradiation significantly increased the intercellular reactive oxygen species (ROS production and matrix metalloproteinases (MMPs activities and decreased the content of collagen in MEFs. LSGYGP reduced the intercellular ROS generation in UVB-induced MEFs. Meanwhile, the decrease of superoxide dismutase (SOD activity and the increase of malondiaidehyde (MDA content were inhibited by LSGYGP. LSGYGP reduced MMP-1 and MMP-9 activities in a dose-dependent manner. Molecular docking simulation indicated that LSGYGP inhibited MMPs activities by docking the active sites of MMP-1 and MMP-9. Furthermore, LSGYGP also affected the intercellular phosphorylation of UVB-induced the mitogen-activated protein kinase pathway. LSGYGP could protect collagen synthesis in MEFs under UVB irradiation by inhibiting oxidative stress and regulating MMPs activities.

  8. Caffeic acid and ferulic acid inhibit UVA-induced matrix metalloproteinase-1 through regulation of antioxidant defense system in keratinocyte HaCaT cells.

    Science.gov (United States)

    Pluemsamran, Thanyawan; Onkoksoong, Tasanee; Panich, Uraiwan

    2012-01-01

    Ultraviolet A (UVA) plays a vital role in the pathogenesis of premature skin aging through keratinocyte cytotoxicity and degradation of collagen, a main component of the extracellular matrix providing structural support. Oxidative stress caused by UVA irradiation can mediate induction of matrix metalloprotease-1 (MMP-1), a major enzyme responsible for collagen damage. Protection against UV-mediated disturbance of antioxidant defense system has been proposed as a possible mechanism by which botanical compounds slow down skin aging process. This study therefore aimed to assess inhibitory effects of caffeic acid (CA) and ferulic acid (FA), powerful plant-based phenolic antioxidants, on UVA-induced cytotoxicity and MMP-1 activity and mRNA level through modulation of antioxidant defense mechanism in immortalized human keratinocyte (HaCaT) cells. Pretreatment of the cells with CA or FA prior to UVA irradiation inhibited cytotoxicity, induction of MMP-1 activity and mRNA and oxidant formation. Moreover, CA and FA were able to up-regulate glutathione (GSH) content, γ-glutamate cysteine ligase (γ-GCL) mRNA as well as activities and mRNA expression of catalase and glutathione peroxidase (GPx) in irradiated cells. In conclusion, CA and FA provided protective effects on UVA-mediated MMP-1 induction in HaCaT cells possibly through restoration of antioxidant defense system at the cellular and molecular level. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  9. Matrix superpotentials

    Science.gov (United States)

    Nikitin, Anatoly G.; Karadzhov, Yuri

    2011-07-01

    We present a collection of matrix-valued shape invariant potentials which give rise to new exactly solvable problems of SUSY quantum mechanics. It includes all irreducible matrix superpotentials of the generic form W=kQ+\\frac{1}{k} R+P, where k is a variable parameter, Q is the unit matrix multiplied by a real-valued function of independent variable x, and P and R are the Hermitian matrices depending on x. In particular, we recover the Pron'ko-Stroganov 'matrix Coulomb potential' and all known scalar shape invariant potentials of SUSY quantum mechanics. In addition, five new shape invariant potentials are presented. Three of them admit a dual shape invariance, i.e. the related Hamiltonians can be factorized using two non-equivalent superpotentials. We find discrete spectrum and eigenvectors for the corresponding Schrödinger equations and prove that these eigenvectors are normalizable.

  10. Effect of pioglitazone, quercetin and hydroxy citric acid on extracellular matrix components in experimentally induced non-alcoholic steatohepatitis

    Directory of Open Access Journals (Sweden)

    Surapaneni Krishna Mohan

    2015-08-01

    Results:The experimental NASH rats treated with pioglitazone showed significant decrease in the levels of hyaluronic acid and significant increase in adiponectin levels when compared to experimentally induced NASH group, but did not show any effect on the levels of leptin. Contrary to these two drugs, viz. pioglitazone and hydroxy citric acid, the group treated with quercetin showedsignificant decrease in the levels of hyaluronic acid and leptin and significant decrease in adiponectin levels compared with that of experimentally induced NASH NASH group, offering maximum protection against NASH. Conclusion: Considering our findings, it could be concluded that quercetin may offer maximum protection against NASH by significantly increasing the levels of adiponectin, when compared to pioglitazone and hydroxy citric acid.

  11. Ethyl group as matrix modifier and inducer of ordered domains in hybrid xerogels synthesised in acidic media using ethyltriethoxysilane (ETEOS) and tetraethoxysilane (TEOS) as precursors

    International Nuclear Information System (INIS)

    Rios, Xabier; Moriones, Paula; Echeverría, Jesús C.; Luquin, Asunción; Laguna, Mariano; Garrido, Julián J.

    2013-01-01

    Hybrid silica xerogels favourably combine the properties of organic and inorganic components in one material; consequently these materials are useful for multiple applications. The versatility and mild synthetic conditions provided by the sol-gel process are ideal for the synthesis of hybrid materials. The specific aims of this study were to synthesise hybrid xerogels in acidic media using tetraethoxysilane (TEOS) and ethyltriethoxysilane (ETEOS) as silica precursors, and to assess the role of the ethyl group as a matrix modifier and inducer of ordered domains in xerogels. All xerogels were synthesised at pH 4.5, at 60 °C, with 1:4.75:5.5 TEOS:EtOH:H 2 O molar ratio. Gelation time exponentially increased with the ETEOS molar ratio. Incorporation of the ethyl groups into the structure of xerogels reduced cross-linking, increased the average siloxane bond length, and promoted the formation of ordered domains. As a result, a transition from Q n to T n signals detected in the 29 Si NMR spectra, the Si–O structural band in the FTIR spectra shifted to lower wavelength, and a new peak in the XRD pattern at 2θ < 10° appeared in the XRD patterns. Mass spectroscopy detected fragments with high numbers of silicon atoms and a polymeric distribution. - Graphical abstract: Display Omitted - Highlights: • Hybrid xerogels were synthesised for ETEOS/TEOS mixtures up to 80% ETEOS. • The gelification time exponentially increased with ETEOS content. • FTIR, XRD and MAS NMR demonstrated the presence of ethyl groups into xerogels. • For ETEOS contents ≤30%, ethyl group acted as matrix modifier. • For ETEOS contents ≥30%, ethyl groups induced the formation of ordered domains

  12. Influence of acute and chronic streptozotocin-induced diabetes on the rat tendon extracellular matrix and mechanical properties

    DEFF Research Database (Denmark)

    Volper, Brent D; Huynh, Richard T; Arthur, Kathryn A

    2015-01-01

    Diabetes is a major risk factor for tendinopathy, and tendon abnormalities are common in diabetic patients. The purpose of the present study was to evaluate the effect of streptozotocin (60 mg/kg)-induced diabetes and insulin therapy on tendon mechanical and cellular properties. Sprague-Dawley rats....... Future studies could attempt to further address the mechanisms contributing to the increase in tendon problems noted in diabetic patients, especially since our data suggest that hyperglycemia per se does not alter tendon mechanical properties....

  13. Matrix-Induced Autologous Chondrocyte Implantation (MACI) Using a Cell-Seeded Collagen Membrane Improves Cartilage Healing in the Equine Model.

    Science.gov (United States)

    Nixon, Alan J; Sparks, Holly D; Begum, Laila; McDonough, Sean; Scimeca, Michael S; Moran, Nance; Matthews, Gloria L

    2017-12-06

    Autologous chondrocyte implantation (ACI) using a collagen scaffold (matrix-induced ACI; MACI) is a next-generation approach to traditional ACI that provides the benefit of autologous cells and guided tissue regeneration using a biocompatible collagen scaffold. The MACI implant also has inherent advantages including surgical implantation via arthroscopy or miniarthrotomy, the elimination of periosteal harvest, and the use of tissue adhesive in lieu of sutures. This study evaluated the efficacy of the MACI implant in an equine full-thickness cartilage defect model at 1 year. Autologous chondrocytes were seeded onto a collagen type-I/III membrane and implanted into one of two 15-mm defects in the femoral trochlear ridge of 24 horses. Control defects either were implanted with cell-free collagen type-I/III membrane (12 horses) or were left ungrafted as empty defects (12 horses). An additional 3 horses had both 15-mm defects remain empty as nonimplanted joints. The repair was scored by second-look arthroscopy (12 weeks), and necropsy examination (53 weeks). Healing was assessed by arthroscopic scoring, gross assessment, histology and immunohistology, cartilage matrix component assay, and gene expression determination. Toxicity was examined by prostaglandin E2 formation in joint fluid, and lymph node morphology combined with histologic screening of organs. MACI-implanted defects had improved gross healing and composite histologic scores, as well as increases in chondrocyte predominance, toluidine blue-stained matrix, and collagen type-II content compared with scaffold-only implanted or empty defects. There was minimal evidence of reaction to the implant in the synovial membrane (minor perivascular cuffing), subchondral bone, or cartilage. There were no adverse clinical effects, signs of organ toxicity, or evidence of chondrocytes or collagen type-I/III membrane in draining lymph nodes. The MACI implant appeared to improve cartilage healing in a critical-sized defect in

  14. Histamine induces the production of matrix metalloproteinase-9 in human astrocytic cultures via H1-receptor subtype.

    Science.gov (United States)

    Patel, Aarti; Vasanthan, Vishnu; Fu, Wen; Fahlman, Richard P; MacTavish, David; Jhamandas, Jack H

    2016-05-01

    Accumulation of β-amyloid (Aβ) protein within the brain is a neuropathological hallmark of Alzheimer's disease (AD). One strategy to facilitate Aβ clearance from the brain is to promote Aβ catabolism. Matrix metalloproteinase-9 (MMP-9), a member of the family of Zn(+2)-containing endoproteases, known to be expressed and secreted by astrocytes, is capable of degrading Aβ. Histamine, a major aminergic brain neurotransmitter, stimulates the production of MMP-9 in keratinocytes through the histamine H1 receptor (H1R). In the present study, we show that histamine evokes a concentration- and calcium-dependent release of MMP-9 from human astrocytic U373 cells and primary cultures of human and rat astrocytes through the H1R subtype. Activation of H1R on astrocytes elevated intracellular levels of Ca(2+) that was accompanied by time-dependent increases in MAP kinase p44/p42 and PKC. In-cell western blots revealed dose-dependent increases in both enzymes, confirming involvement of these signal transduction pathways. We next investigated the extent of recombinant human MMP-9 (rhMMP-9) proteolytic activity on soluble oligomeric Aβ (soAβ). Mass spectrometry demonstrated time-dependent cleavage of soAβ (20 μM), but not another amyloidogenic protein amylin, upon incubation with rhMMP-9 (100 nM) at 1, 4 and 17 h. Furthermore, Western blots showed a shift in soAβ equilibrium toward lower order, less toxic monomeric species. In conclusion, both MAPK p44/p42 and PKC pathways appear to be involved in histamine-upregulated MMP-9 release via H1Rs in astrocytes. Furthermore, MMP-9 appears to cleave soAβ into less toxic monomeric species. Given the key role of histamine in MMP-9 release, this neurotransmitter may serve as a potential therapeutic target for AD.

  15. Inhibition of matrix metalloproteinases-2 and -9 prevents cognitive impairment induced by pneumococcal meningitis in Wistar rats.

    Science.gov (United States)

    Barichello, Tatiana; Generoso, Jaqueline S; Michelon, Cleonice M; Simões, Lutiana R; Elias, Samuel G; Vuolo, Franciele; Comim, Clarissa M; Dal-Pizzol, Felipe; Quevedo, João

    2014-02-01

    Pneumococcal meningitis is a relevant clinical disease characterized by an intense inflammatory reaction into the subarachnoid and ventricular spaces, leading to blood-brain barrier breakdown, hearing loss, and cognitive impairment. Matrix metalloproteinases (MMPs) are capable of degrading components of the basal laminin, thus contributing to BBB damage and neuronal injury. In the present study, we evaluated the effects of MMP-2, MMP-9, and MMP-2/9 inhibitors on BBB integrity, learning, and memory in Wistar rats subjected to pneumococcal meningitis. The animals underwent a magna cistern tap and received either 10 µL sterile saline as a placebo or an equivalent volume of a Streptococcus pneumoniae suspension at a concentration of 5 × 10(9)cfu/mL. The rats were randomized into different groups that received adjuvant treatment with MMP-2, MMP-9 or MMP-2/9 inhibitors. The BBB integrity was evaluated, and the animals were habituated to open-field and object recognition tasks 10 days after meningitis induction. Adjuvant treatments with inhibitors of MMP-2 or MMP-2/9 prevented BBB breakdown in the hippocampus, and treatments with inhibitors of MMP-2, MMP-9 or MMP-2/9 prevented BBB breakdown in the cortex. Ten days after meningitis induction, the animals that received adjuvant treatment with the inhibitor of MMP-2/9 demonstrated that animals habituated to the open-field task faster and enhanced memory during short-term and long-term retention test sessions in the object recognition task. Further investigation is necessary to provide support for MMP inhibitors as an alternative treatment for bacterial meningitis; however, these findings suggest that the meningitis model could be a good research tool for studying the biological mechanisms involved in the behavioral alterations associated with pneumococcal meningitis.

  16. Cadmium induces matrix metalloproteinase-9 expression via ROS-dependent EGFR, NF-kB, and AP-1 pathways in human endothelial cells

    International Nuclear Information System (INIS)

    Lian, Sen; Xia, Yong; Khoi, Pham Ngoc; Ung, Trong Thuan; Yoon, Hyun Joong; Kim, Nam Ho; Kim, Kyung Keun; Jung, Young Do

    2015-01-01

    Highlights: • Cadmium induces MMP-9 expression through NADPH oxidase-derived ROS. • Cadmium induces MMP-9 through EGFR-mediated Akt, Erk1/2 and JNK1/2 signaling pathways. • Akt, MAPKs (Erk1/2 and JNK1/2) functioned as upstream signals of NF-kB and AP-1 respectively, in cadmium-induced MMP-9 in endothelial cells. • ROS production by NADPH oxidase is the furthest upstream signal in MMP-9 expression in ECV304 cells. - Abstract: Cadmium (Cd), a widespread cumulative pollutant, is a known human carcinogen, associated with inflammation and tumors. Matrix metalloproteinase-9 (MMP-9) plays a pivotal role in tumor metastasis; however, the mechanisms underlying the MMP-9 expression induced by Cd remain obscure in human endothelial cells. Here, Cd elevated MMP-9 expression in dose- and time-dependent manners in human endothelial cells. Cd increased ROS production and the ROS-producing NADPH oxidase. Cd translocates p47 phox , a key subunit of NADPH oxidase, to the cell membrane. Cd also activated the phosphorylation of EGFR, Akt, Erk1/2, and JNK1/2 in addition to promoting NF-kB and AP-1 binding activities. Specific inhibitor and mutagenesis studies showed that EGFR, Akt, Erk1/2, JNK1/2 and transcription factors NF-κB and AP-1 were related to Cd-induced MMP-9 expression in endothelial cells. Akt, Erk1/2, and JNK1/2 functioned as upstream signals in the activation of NF-κB and AP-1, respectively. In addition, N-acetyl-L-cystein (NAC), diphenyleneiodonium chloride (DPI) and apocynin (APO) inhibited the Cd-induced activation of EGFR, Akt, Erk1/2, JNK1/2, and p38 MAPK, indicating that ROS production by NADPH oxidase is the furthest upstream signal in MMP-9 expression. At present, it states that Cd displayed marked invasiveness in ECV304 cells, which was partially abrogated by MMP-9 neutralizing antibodies. These results demonstrated that Cd induces MMP-9 expression via ROS-dependent EGFR- > Erk1/2, JNK1/2- > AP-1 and EGFR- > Akt- > NF-κB signaling pathways and, in turn

  17. Role of the Autotaxin-LPA Pathway in Dexamethasone-Induced Fibrotic Responses and Extracellular Matrix Production in Human Trabecular Meshwork Cells.

    Science.gov (United States)

    Honjo, Megumi; Igarashi, Nozomi; Nishida, Junko; Kurano, Makoto; Yatomi, Yutaka; Igarashi, Koji; Kano, Kuniyuki; Aoki, Junken; Aihara, Makoto

    2018-01-01

    Dexamethasone (Dex) regulates aqueous humor outflow by inducing reorganization of the cytoskeleton and extracellular matrix (ECM) production. Rho kinase (ROCK) has an important role in this process, but the upstream pathway leading to its activation remains elusive. The purpose of the study was to determine the role of autotaxin (ATX), an enzyme involved in the generation of lysophosphatidic acid (LPA), in the Dex-induced fibrotic response and ECM production in human trabecular meshwork (HTM) cells. The expression of ATX in specimens from glaucoma patients was investigated by immunohistochemistry. Regulation of ATX expression and the changes in actin cytoskeleton, ECM production, myosin light chain (MLC) and cofilin phosphorylation, ATX secretion, and lysophospholipase D (lysoPLD) activity induced by Dex treatment in HTM cells were determined by immunofluorescence, real-time quantitative PCR, immunoblot, and the two-site immunoenzymetric and lysoPLD assays. Significant ATX expression was found in conventional outflow pathway specimens from glaucoma patients. Dex treatment induced increases in ATX mRNA levels, protein expression, and secretion in HTM cells in association with reorganization of cytoskeleton and ECM accumulation. Significant suppression of these aforementioned changes was observed after ATX/LPA-receptor/ROCK inhibition as well as suppression of fibrotic changes and MLC and cofilin phosphorylation in HTM cells. The results of this study, including the robust induction of ATX by Dex treatment, in association with fibrotic changes and ECM production in HTM cells, collectively suggest a potential role for ATX-LPA pathway in the regulation of aqueous humor outflow and IOP in glaucomatous eyes.

  18. Matrix-isolation studies on the radiation-induced chemistry in H₂O/CO₂ systems: reactions of oxygen atoms and formation of HOCO radical.

    Science.gov (United States)

    Ryazantsev, Sergey V; Feldman, Vladimir I

    2015-03-19

    The radiation-induced transformations occurring upon X-ray irradiation of solid CO2/H2O/Ng systems (Ng = Ar, Kr, Xe) at 8-10 K and subsequent annealing up to 45 K were studied by Fourier transform infrared spectroscopy. The infrared (IR) spectra of deposited matrices revealed the presence of isolated monomers, dimers, and intermolecular H2O···CO2 complexes. Irradiation resulted in effective decomposition of matrix-isolated carbon dioxide and water yielding CO molecules and OH radicals, respectively. Annealing of the irradiated samples led to formation of O3, HO2, and a number of xenon hydrides of HXeY type (in the case of xenon matrices). The formation of these species was used for monitoring of the postirradiation thermally induced chemical reactions involving O and H atoms generated by radiolysis. It was shown that the radiolysis of CO2 in noble-gas matrices produced high yields of stabilized oxygen atoms. In all cases, the temperatures at which O atoms become mobile and react are lower than those of H atoms. Dynamics and reactivity of oxygen atoms was found to be independent of the precursor nature. In addition, the formation of HOCO radicals was observed in all the noble-gas matrices at remarkably low temperatures. The IR spectra of HOCO and DOCO were first characterized in krypton and xenon matrices. It was concluded that the formation of HOCO was mainly due to the radiation-induced evolution of the weakly bound H2O···CO2 complexes. This result indicates the significance of weak intermolecular interactions in the radiation-induced chemical processes in inert low-temperature media.

  19. Identification and partial characterization of two inducible gelatin-cleavage activities localized to the sea urchin extraembryonic matrix, the hyaline layer.

    Science.gov (United States)

    Robinson, John J; Sharpe, Christopher; Calloway, Carolyn

    2003-04-07

    We have identified two inducible, gelatin-cleaving activities in the sea urchin extraembryonic matrix, the hyaline layer. Isolated hyaline layers, incubated in the presence of benzamidine, were devoid of gelatin-cleavage activities with apparent molecular mass less then 80k. However, when layers were incubated for 9-11 h in the absence of benzamidine, gelatin-cleavage activities, with apparent molecular mass 40- and 50k, were detected. Induction required the presence of NaCl and CaCl(2) at concentrations similar to those found in seawater and readdition of the reversible serine protease inhibitor benzamidine prevented induction. Both gelatin-cleaving activities were activated by calcium at a concentration similar to the calcium concentration found in seawater. Magnesium, also a major cationic species present in seawater, could not replace calcium as the activating ion. In addition, magnesium could not compete with calcium for binding to the gelatinases. Both cleavage activities showed substrate specificity and each failed to cleave bovine serum albumin, bovine hemoglobin or casein. Cleavage activity towards gelatin was inhibited by benzamidine and aminoethyl benzenesulfonyl fluoride, indicating that both activities belonged to the serine class of proteases. The induced 40-kDa activity displayed similar properties to those of a comigrating, gelatin-cleaving activity present in 69-h-old embryos.

  20. Irradiation by pulsed Nd:YAG laser induces the production of extracellular matrix molecules by cells of the connective tissues: a tool for tissue repair

    Science.gov (United States)

    Monici, Monica; Basile, Venere; Cialdai, Francesca; Romano, Giovanni; Fusi, Franco; Conti, Antonio

    2008-04-01

    Many studies demonstrated that mechanical stress is a key factor for tissue homeostasis, while unloading induce loss of mass and impairment of function. Because of their physiological function, muscle, connective tissue, bone and cartilage dynamically interact with mechanical and gravitational stress, modifying their properties through the continuous modification of their composition. Indeed, it is known that mechanical stress increases the production of extracellular matrix (ECM) components by cells, but the mechanotransduction mechanisms and the optimal loading conditions required for an optimal tissue homeostasis are still unknown. Considering the importance of cell activation and ECM production in tissue regeneration, a proper use of mechanical stimulation could be a powerful tool in tissue repair and tissue engineering. Studies exploring advanced modalities for supplying mechanical stimuli are needed to increase our knowledge on mechanobiology and to develop effective clinical applications. Here we describe the effect of photomechanical stress, supplied by a pulsed Nd:YAG laser on ECM production by cells of connective tissues. Cell morphology, production of ECM molecules (collagens, fibronectin, mucopolysaccharides), cell adhesion and cell energy metabolism have been studied by using immunofluorescence and autofluorescence microscopy. The results show that photomechanical stress induces cytoskeleton remodelling, redistribution of membrane integrins, increase in production of ECM molecules. These results could be of consequence for developing clinical protocols for the treatment of connective tissue dideases by pulsed Nd:YAG laser.

  1. Inhibition of matrix metalloproteinase-9 by a barbiturate-nitrate hybrid ameliorates dextran sulphate sodium-induced colitis: effect on inflammation-related genes.

    Science.gov (United States)

    O'Sullivan, Shane; Wang, Jun; Pigott, Maria T; Docherty, Neil; Boyle, Noreen; Lis, Samuel Kana; Gilmer, John F; Medina, Carlos

    2017-04-01

    Matrix metalloproteinase-9 (MMP-9) is up-regulated in ulcerative colitis and implicated in the pathology of the disease. In this study, we have examined the effects of a barbiturate-based MMP inhibitor incorporating a nitric oxide donor/mimetic group (dinitrate-barbiturate) on the intestinal injury induced by dextran sulphate sodium (DSS). In vivo experiments were carried out using male Wistar rats given 5% DSS ad libitum in drinking water. The dinitrate-barbiturate, non-nitrate equivalent, nitrate side chains alone or vehicle were administered rectally, twice daily. MMP-9 release was measured by gelatin zymography, and analysis of gene expression was carried out using RT-qPCR. TaqMan low density arrays were used to evaluate the expression of 91 inflammatory genes in the rat colon. The dinitrate-barbiturate inhibited the induction and activity of MMP-9 during DSS colitis in the rat. This occurred in association with significant reductions in the colitic response to DSS as assessed by an established clinical disease activity index and a pathological colitis grade score. The compound modified expression rates of numerous inflammation-related genes in the colon. This study demonstrated the efficacy of the dinitrate-barbiturate in DSS-induced colitis. Therefore, barbiturate-nitrate hybrids may be developed as a promising anti-inflammatory approach to the treatment of inflammatory bowel disease. © 2017 The British Pharmacological Society.

  2. Infrared spectra and ultraviolet-tunable laser induced photochemistry of matrix-isolated phenol and phenol-d5.

    Science.gov (United States)

    Giuliano, Barbara Michela; Reva, Igor; Lapinski, Leszek; Fausto, Rui

    2012-01-14

    Monomers of phenol and its ring-perdeuterated isotopologue phenol-d(5) were isolated in argon matrices at 15 K. The infrared (IR) spectra of these species were recorded and analyzed. In situ photochemical transformations of phenol and phenol-d(5) were induced by tunable UV laser light. The photoproducts have been characterized by IR spectroscopy supported by theoretical calculations of the infrared spectra. The primary product photogenerated from phenol was shown to be the phenoxyl radical. The analysis of the progress of the observed phototransformations led to identification of 2,5-cyclohexadienone as one of the secondary photoproducts. Spectral indications of other secondary products, such as the Dewar isomer and the open-ring ketene, were also detected. Identification of the photoproducts provided a guide for the interpretation of the mechanisms of the observed photoreactions.

  3. Matrix thermalization

    Energy Technology Data Exchange (ETDEWEB)

    Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University, Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Nguyen, Kévin [Theoretische Natuurkunde, Vrije Universiteit Brussel (VUB), and International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium)

    2017-02-08

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  4. VERY LOW-DOSE (FEMTOMOLAR) 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) DISRUPTS STEROIDOGENIC ENZYME mRNAs AND STEROID SECRETION BY HUMAN LUTEINIZING GRANULOSA CELLS

    Science.gov (United States)

    Baldridge, MG; Marks, GT; Rawlins, RG; Hutz, RJ

    2015-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic congener of the polyhalogenated aromatic hydrocarbons (PAH), which causes anatomical abnormalities and developmental defects, impairs ovulation and reduces fertility. TCDD’s endocrine-disrupting effects are, in part, caused by a direct action at the ovary. Herein we investigated the in-vitro effects of environmentally relevant doses of TCDD on estradiol-17β (E2) production by human luteinizing granulosa cells (hLGC) obtained from women stimulated for in-vitro fertilization (IVF). TCDD at all concentrations tested (3.1 fM, 3.1 pM and 3.1 nM) significantly decreased E2 secretion when assayed for by radioimmunoassay (RIA). Herein we confirm that TCDD alters E2 secretion by hLGC in a time-, not dose-dependent fashion and are the first to show decreases in E2 secretion with fM concentrations of TCDD. Using real-time quantitative PCR (RT-qPCR), the decreased E2 secretion correlates with a decrease in the mRNA expression levels two enzymes in the estrogen biosynthesis pathway: CYP11A1 and CYP19A1. PMID:25697571

  5. House Dust Mites Induce Production of Endothelin-1 and Matrix Metalloproteinase-9 in Keratinocytes via Proteinase-Activated Receptor-2 Activation.

    Science.gov (United States)

    Yamada, Yoshihito; Matsumoto, Tatsumi

    2017-01-01

    Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by skin barrier dysfunction and abnormal immune response. House dust mites (HDM) are a major source of allergens, some of which have cysteine and serine protease activities. Keratinocytes stimulated by HDM-derived proteases have been suggested to contribute to the pathogenesis of AD by producing various cytokines. However, whether keratinocytes contribute to the induction of pruritus in AD, especially by producing pruritus-related mediators upon stimulation with HDM-derived proteases, has not been fully elucidated. We examined whether the production of endothelin-1 (ET-1), matrix metalloproteinase (MMP)-2, and MMP-9 in keratinocytes can be induced by stimulation with Dermatophagoides farinae extracts, and if so, whether pretreatment with a protease inhibitor or proteinase-activated receptor-2 (PAR-2) antagonist affects the production of these mediators in keratinocytes. Although MMP-2 levels were undetectable in the culture supernatants, the production of ET-1 and MMP-9 was increased upon stimulation with HDM extracts in a concentration- and time-dependent manner and suppressed by pretreatment of HDM extracts with serine protease inhibitor, but not with cysteine protease inhibitor. Mite-derived serine proteases also induced ET-1 and MMP-9 production in a concentration- and time-dependent manner. Moreover, pretreatment with a PAR-2 antagonist inhibited the production of ET-1 and MMP-9 in keratinocytes. These results suggest that the activation of PAR-2 on keratinocytes by HDM-derived serine proteases induces the production of ET-1 and MMP-9, and may contribute to the induction of pruritus in AD. © 2017 S. Karger AG, Basel.

  6. Characterization of spray-dried microalgal oil encapsulated in cross-linked sodium caseinate matrix induced by microbial transglutaminase.

    Science.gov (United States)

    Bao, Shan-Shan; Hu, Xue-Chao; Zhang, Ka; Xu, Xiao-Kang; Zhang, Hong-Man; Huang, He

    2011-01-01

    Sodium caseinate (SC) cross-linked by microbial transglutaminase (MTGase) for encapsulating microalgal oil was investigated. Protein cross-linking was evidenced in the SDS-PAGE graph. The emulsifying properties of SC depended on the cross-linked time with MTGase. The emulsifying activity and stability indexes of SC increased with the cross-linking time of 30 to 90 min (P30 to P90), and then declined with longer cross-linked time of 180 to 420 min (P180 to P420). The P30 to P90 as wall material for microencapsulation was superior to P180 to P420 and control sample. The microcapsules prepared with P30 to P90 showed more than 97% of microencapsulation efficiency in contrast to about 90% with the P180 to P420. During storage, the microcapsules prepared with P30 to P90 exhibited higher oxidative stability as compared with other microcapsules. A sustained release of microalgal oil was observed, and core release was time dependent and affected by cross-linking degree. Results showed that the powdered microalgal oil prepared with P30 to P90 demonstrated enhanced physicochemical properties and oxidative stability. Practical Application: The novel method using cross-linked proteins as wall material induced by microbial transglutaminase in food industry for sensitive ingredients could convert microcapsules into a stable form, which would lead to its more widespread utilization as a kind of food additive.

  7. Chondrocytes Derived From Mesenchymal Stromal Cells and Induced Pluripotent Cells of Patients With Familial Osteochondritis Dissecans Exhibit an Endoplasmic Reticulum Stress Response and Defective Matrix Assembly

    Science.gov (United States)

    Xu, Maojia; Stattin, Eva-Lena; Shaw, Georgina; Heinegård, Dick; Sullivan, Gareth; Wilmut, Ian; Colman, Alan; Önnerfjord, Patrik; Khabut, Areej; Aspberg, Anders; Dockery, Peter; Hardingham, Timothy; Murphy, Mary

    2016-01-01

    Familial osteochondritis dissecans (FOCD) is an inherited skeletal defect characterized by the development of large cartilage lesions in multiple joints, short stature, and early onset of severe osteoarthritis. It is associated with a heterozygous mutation in the ACAN gene, resulting in a Val-Met replacement in the C-type lectin domain of aggrecan. To understand the cellular pathogenesis of this condition, we studied the chondrogenic differentiation of patient bone marrow mesenchymal stromal cells (BM-MSCs). We also looked at cartilage derived from induced pluripotent stem cells (iPSCs) generated from patient fibroblasts. Our results revealed several characteristics of the differentiated chondrocytes that help to explain the disease phenotype and susceptibility to cartilage injury. First, patient chondrogenic pellets had poor structural integrity but were rich in glycosaminoglycan. Second, it was evident that large amounts of aggrecan accumulated within the endoplasmic reticulum of chondrocytes differentiated from both BM-MSCs and iPSCs. In turn, there was a marked absence of aggrecan in the extracellular matrix. Third, it was evident that matrix synthesis and assembly were globally dysregulated. These results highlight some of the abnormal aspects of chondrogenesis in these patient cells and help to explain the underlying cellular pathology. The results suggest that FOCD is a chondrocyte aggrecanosis with associated matrix dysregulation. The work provides a new in vitro model of osteoarthritis and cartilage degeneration based on the use of iPSCs and highlights how insights into disease phenotype and pathogenesis can be uncovered by studying differentiation of patient stem cells. Significance The isolation and study of patient stem cells and the development of methods for the generation of iPSCs have opened up exciting opportunities in understanding causes and exploring new treatments for major diseases. This technology was used to unravel the cellular phenotype in

  8. Aryl Hydrocarbon Receptor (AhR Modulates Cockroach Allergen-Induced Immune Responses through Active TGFβ1 Release

    Directory of Open Access Journals (Sweden)

    Yufeng Zhou

    2014-01-01

    Full Text Available Background. Aryl hydrocarbon receptor (AhR, a multifunctional regulator that senses and responds to environmental stimuli, plays a role in normal cell development and immune regulation. Recent evidence supports a significant link between environmental exposure and AhR in the development of allergic diseases. We sought to investigate whether AhR plays a role in mediating cockroach allergen-induced allergic immune responses. Methods. AhR expression in human lung fibroblasts from asthmatic and healthy individuals and in cockroach extract (CRE treated human lung fibroblasts (WI-38 was examined. The role of AhR in modulating CRE induced TGFβ1 production was investigated by using AhR agonist, TCDD, antagonist CH122319, and knockdown of AhR. The role of latent TGFβ1 binding protein-1 (LTBP1 in mediating TCDD induced active TGFβ1 release was also examined. Results. AhR expression was higher in airway fibroblasts from asthmatic subjects as compared to healthy controls. AhR in fibroblasts was activated by TCDD with an increased expression of cyp1a1 and cyp1b1. Increased AhR expression was observed in CRE-treated fibroblasts. Importantly, CRE induced TGFβ1 production in fibroblasts was significantly enhanced by TCDD but inhibited by CH122319. Reduced TGFβ1 production was further confirmed in fibroblasts with AhR knockdown. Moreover, AhR knockdown inhibited CRE induced fibroblast differentiation. Furthermore, TCDD induced active TGFβ1 release was significantly inhibited by LTBP1 knockdown. Conclusion. These results provide evidence for the role of AhR in modulating cockroach allergen-induced immune responses through controlling the active TGFβ1 release, suggesting a possible synergistic effect between exposure to allergens and environmental chemicals on the development of allergic diseases.

  9. Duration of immunity induced by an equine influenza and tetanus combination vaccine formulation adjuvanted with ISCOM-Matrix.

    Science.gov (United States)

    Heldens, J G M; Pouwels, H G W; Derks, C G G; Van de Zande, S M A; Hoeijmakers, M J H

    2010-10-08

    Equine influenza is a contagious disease caused by equine influenza virus which belongs to the orthomyxovirus family. Outbreaks of equine influenza cause severe economic loses to the horse industry and consequently horses in competition are required to be regularly vaccinated against equine influenza. Unlike the existing inactivated vaccines, Equilis Prequenza Te is the only one able to induce protection against clinical disease and virus excretion after a primary vaccination course consisting of two vaccine applications 4-6 weeks apart until the recommended time of the third vaccination. In this paper we describe the duration of immunity profile, tested in an experimental setting according to European legislation, of this inactivated equine influenza and tetanus combination vaccine. In addition to influenza antigen, the formulation contains a second generation ISCOM (the so called ISCOMatrix) as an adjuvant. The vaccine aims at the induction of protection from the primary vaccination course until the time of annual revaccination 12 months later, against challenge with a virulent equine influenza strain. The protection against A/equine/Kentucky/95 (H3N8) at the time of annual revaccination was evidenced by a significant reduction of clinical signs of influenza, a significant reduction of virus excretion and a significant reduction of fever. The effect of the annual revaccination on the duration of immunity against influenza and tetanus was also studied by serology. For tetanus, as a consequence of the 24 months duration of immunity, an alternating annual vaccination schedule consisting of Prequenza and Prequenza Te is proposed after the first three doses of Prequenza Te. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Interleukin-1beta-induced release of matrix proteins into culture media causes inhibition of mineralization of nodules formed by periodontal ligament cells in vitro.

    Science.gov (United States)

    Chien, H H; Lin, W L; Cho, M I

    1999-05-01

    The mechanism by which interleukin-1beta (IL-1) inhibits the formation of mineralized tissue nodules by periodontal ligament (PDL) cells in vitro was investigated through the processes of morphological analysis, immunoprecipitation, and Northern blot analysis. PDL cells were obtained from a 2-day-old coagulum in tooth socket and cultured in Dulbecco's Modified Eagle Medium (DMEM) containing 10% fetal bone serum (FBS) and antibiotics. Confluent cells were grown for up to 3 weeks in the presence of ascorbic acid (AA), beta-glycerophosphate (GP), and dexamethasone (Dex), or IL-1. PDL cells cultured in the presence of GP and AA did not differentiate, but those treated with Dex, GP, and AA (Dex group) underwent differentiation, showing four stages (confluent, multilayer, nodule, and mineralization) of disparate morphological characteristics. In contrast, the cells treated with IL-1, Dex, GP, and AA (IL-1 group) did form multilayers but failed to form mineralized nodules. Electron microscopy demonstrated that the Dex-induced mineralized nodules contain multilayers of fibroblastic cells, numerous collagen fibrils, and dense globular as well as fused electron dense patches that are associated with numerous apatite crystals. The nodule-like structures in the IL-1 group were also comprised of multilayered fibroblastic cells, but they contained only a small number of collagen fibrils, and no dense globular or fused patches. Von Kossa staining confirmed the presence of numerous mineralized nodules in the Dex group and their scarceness in the IL-1 group. Northern blot analysis of IL-1-treated cells, however, revealed the presence of mRNAs for type I collagen (Col I), secreted protein, acidic and rich in cysteine (SPARC), osteopontin (OPN), alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteocalcin (OC), whose expression patterns and levels were comparable to those of the Dex group. Immunoprecipitation analysis of OPN and BSP in the cell/matrix layers and the culture

  11. The Reciprocal Pascal Matrix

    OpenAIRE

    Richardson, Thomas M.

    2014-01-01

    The reciprocal Pascal matrix is the Hadamard inverse of the symmetric Pascal matrix. We show that the ordinary matrix inverse of the reciprocal Pascal matrix has integer elements. The proof uses two factorizations of the matrix of super Catalan numbers.

  12. Matrix inequalities

    CERN Document Server

    Zhan, Xingzhi

    2002-01-01

    The main purpose of this monograph is to report on recent developments in the field of matrix inequalities, with emphasis on useful techniques and ingenious ideas. Among other results this book contains the affirmative solutions of eight conjectures. Many theorems unify or sharpen previous inequalities. The author's aim is to streamline the ideas in the literature. The book can be read by research workers, graduate students and advanced undergraduates.

  13. Experimental study on inhibitory effect of niacinamide on tumor necrosis factor-alpha-induced matrix degradation of annulus fibrous tissue in vitro.

    Science.gov (United States)

    Xu, Runbing; Shao, Zengwu; Xiong, Liming

    2008-10-01

    The inhibitory effect of niacinamide on tumor necrosis factor-alpha (TNF-alpha) induced annulus fibrous (AF) degradation was assessed, and the mechanism of the inhibition was investigated. Chiba's intervertebral disc (IVD) culture model was established. Forty-eight IVDs from 12 adult Japanese white rabbits were randomly divided into 4 groups (12 IVDs in each group), and various concentrations of niacinamide and TNF-alpha were added to the medium for intervention: negative control group, niacinamide control group (0.5 mg/mL niacinamide), degeneration group (10 ng/mL TNF-alpha), and treatment group (0.5 mg/mL niacinamide and 10 ng/mL TNF-alpha). After one week's culture, AFs were collected for glycosaminoglycan (GS) content measurement, safranin O-fast green staining, and immunohistochemical staining for type I, II collagen and cysteine containing aspartate specific protease-3 (Caspase-3). It was found that the GS content in treatment group was increased by about 48% as compared with degeneration group (t=16.93, Pniacinamide control group (t=0.71, P=0.667). Safranine O-fast green staining exhibited higher staining density and better histological structure of AF in the treatment group as compared with the degeneration group. Immunohistochemical staining for both Type I and II collagen demonstrated that lamellar structure and continuity of collagen in treatment group were better reserved than in degeneration group. Positive staining rate of Caspase-3 in AFs of negative control group, niacinamide control group, degeneration group and treatment group was 3.4%, 4.3%, 17.9% and 10.3% respectively. The positive rate in treatment group was significantly lower than in degeneration group (Pniacinamide could effectively alleviate TNF-alpha induced destruction and synthesis inhibition of matrix ingredients in AFs. The inhibition may be related with reduction of expression of Caspase-3. Thus, niacinamide is of potential for IVD degeneration clinical treatment.

  14. Aliskiren attenuates bleomycin-induced pulmonary fibrosis in rats: focus on oxidative stress, advanced glycation end products, and matrix metalloproteinase-9.

    Science.gov (United States)

    Abuelezz, Sally A; Hendawy, Nevien; Osman, Wesam M

    2016-08-01

    Pulmonary fibrosis is a progressive lung disorder with high mortality rate and limited successful treatment. This study was designed to assess the potential anti-oxidant and anti-fibrotic effects of aliskiren (Alsk) during bleomycin (BLM)-induced pulmonary fibrosis. Male Wistar rats were used as control untreated or treated with the following: a single dose of 2.5 mg/kg of BLM endotracheally and BLM and Alsk (either low dose 30 mg/kg/day or high dose 60 mg/kg/day), and another group was given Alsk 60 mg/kg/day alone. Alsk was given by gavage. Alsk anti-oxidant and anti-fibrotic effects were assessed. BLM significantly increased relative lung weight and the levels of lactate dehydrogenase and total and differential leucocytic count in bronchoalveolar lavage that was significantly ameliorated by high-dose Alsk treatment. As markers of oxidative stress, BLM caused a significant increase in the levels of lipid peroxides and nitric oxide accompanied with a significant decrease of superoxide dismutase and glutathione transferase enzymes. High-dose Alsk treatment restored these markers toward normal values. Alsk counteracted the overexpression of advanced glycation end products, matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinases-1 in lung tissue induced by BLM. Fibrosis assessed by measuring hydroxyproline content, which markedly increased in the BLM group, was also significantly reduced by Alsk. These were confirmed by histopathological and immunohistochemical examination which revealed that Alsk attenuates signs of pulmonary fibrosis and decreased the overexpressed MMP-9 and transforming growth factor β1. Collectively, these findings indicate that Alsk has a potential anti-fibrotic effect beside its anti-oxidant activity.

  15. M2 macrophages induce ovarian cancer cell proliferation via a heparin binding epidermal growth factor/matrix metalloproteinase 9 intercellular feedback loop.

    Science.gov (United States)

    Carroll, Molly J; Kapur, Arvinder; Felder, Mildred; Patankar, Manish S; Kreeger, Pamela K

    2016-12-27

    In ovarian cancer, a high ratio of anti-inflammatory M2 to pro-inflammatory M1 macrophages correlates with poor patient prognosis. The mechanisms driving poor tumor outcome as a result of the presence of M2 macrophages in the tumor microenvironment remain unclear and are challenging to study with current techniques. Therefore, in this study we utilized a micro-culture device previously developed by our lab to model concentrated paracrine signaling in order to address our hypothesis that interactions between M2 macrophages and ovarian cancer cells induce tumor cell proliferation. Using the micro-culture device, we determined that co-culture with M2-differentiated primary macrophages or THP-1 increased OVCA433 proliferation by 10-12%. This effect was eliminated with epidermal growth factor receptor (EGFR) or heparin-bound epidermal growth factor (HB-EGF) neutralizing antibodies and HBEGF expression in peripheral blood mononuclear cells from ovarian cancer patients was 9-fold higher than healthy individuals, suggesting a role for HB-EGF in tumor progression. However, addition of HB-EGF at levels secreted by macrophages or macrophage-conditioned media did not induce proliferation to the same extent, indicating a role for other factors in this process. Matrix metalloproteinase-9, MMP-9, which cleaves membrane-bound HB-EGF, was elevated in co-culture and its inhibition decreased proliferation. Utilizing inhibitors and siRNA against MMP9 in each population, we determined that macrophage-secreted MMP-9 released HB-EGF from macrophages, which increased MMP9 in OVCA433, resulting in a positive feedback loop to drive HB-EGF release and increase proliferation in co-culture. Identification of multi-cellular interactions such as this may provide insight into how to most effectively control ovarian cancer progression.

  16. Ovarian matrix metalloproteinases are differentially regulated during the estrous cycle but not during short photoperiod induced regression in Siberian hamsters (Phodopus sungorus

    Directory of Open Access Journals (Sweden)

    Vrooman Lisa A

    2010-06-01

    Full Text Available Abstract Background Matrix metalloproteinases (MMPs are implicated as mediators for ovarian remodeling events, and are involved with ovarian recrudescence during seasonal breeding cycles in Siberian hamsters. However, involvement of these proteases as the photoinhibited ovary undergoes atrophy and regression had not been assessed. We hypothesized that 1 MMPs and their tissue inhibitors, the TIMPs would be present and differentially regulated during the normal estrous cycle in Siberian hamsters, and that 2 MMP/TIMP mRNA and protein levels would increase as inhibitory photoperiod induced ovarian degeneration. Methods MMP-2, -9, -14 and TIMP-1 and -2 mRNA and protein were examined in the stages of estrous (proestrus [P], estrus [E], diestrus I [DI], and diestrus II [DII] in Siberian hamsters, as well as after exposure to 3, 6, 9, and 12 weeks of inhibitory short photoperiod (SD. Results MMP-9 exhibited a 1.6-1.8 fold decrease in mRNA expression in DII (p Conclusions Although MMPs appear to be involved in the normal ovarian estrus cycle at the protein level in hamsters, those examined in the present study are unlikely to be key players in the slow atrophy of tissue as seen in Siberian hamster ovarian regression.

  17. In Vitro and In Vivo Dentinogenic Efficacy of Human Dental Pulp-Derived Cells Induced by Demineralized Dentin Matrix and HA-TCP

    Science.gov (United States)

    Kang, Kyung-Jung; Lee, Min Suk; Moon, Chan-Woong; Lee, Jae-Hoon

    2017-01-01

    Human dental pulp cells have been known to have the stem cell features such as self-renewal and multipotency. These cells are differentiated into hard tissue by addition of proper cytokines and biomaterials. Hydroxyapatite-tricalcium phosphates (HA-TCPs) are essential components of hard tissue and generally used as a biocompatible material in tissue engineering of bone. Demineralized dentin matrix (DDM) has been reported to increase efficiency of bone induction. We compared the efficiencies of osteogenic differentiation and in vivo bone formation of HA-TCP and DDM on human dental pulp stem cells (hDPSCs). DDM contains inorganic components as with HA-TCP, and organic components such as collagen type-1. Due to these components, osteoinduction potential of DDM on hDPSCs was remarkably higher than that of HA-TCP. However, the efficiencies of in vivo bone formation are similar in HA-TCP and DDM. Although osteogenic gene expression and bone formation in immunocompromised nude mice were similar levels in both cases, dentinogenic gene expression level was slightly higher in DDM transplantation than in HA-TCP. All these results suggested that in vivo osteogenic potentials in hDPSCs are induced with both HA-TCP and DDM by osteoconduction and osteoinduction, respectively. In addition, transplantation of hDPSCs/DDM might be more effective for differentiation into dentin. PMID:28761445

  18. In Vitro and In Vivo Dentinogenic Efficacy of Human Dental Pulp-Derived Cells Induced by Demineralized Dentin Matrix and HA-TCP

    Directory of Open Access Journals (Sweden)

    Kyung-Jung Kang

    2017-01-01

    Full Text Available Human dental pulp cells have been known to have the stem cell features such as self-renewal and multipotency. These cells are differentiated into hard tissue by addition of proper cytokines and biomaterials. Hydroxyapatite-tricalcium phosphates (HA-TCPs are essential components of hard tissue and generally used as a biocompatible material in tissue engineering of bone. Demineralized dentin matrix (DDM has been reported to increase efficiency of bone induction. We compared the efficiencies of osteogenic differentiation and in vivo bone formation of HA-TCP and DDM on human dental pulp stem cells (hDPSCs. DDM contains inorganic components as with HA-TCP, and organic components such as collagen type-1. Due to these components, osteoinduction potential of DDM on hDPSCs was remarkably higher than that of HA-TCP. However, the efficiencies of in vivo bone formation are similar in HA-TCP and DDM. Although osteogenic gene expression and bone formation in immunocompromised nude mice were similar levels in both cases, dentinogenic gene expression level was slightly higher in DDM transplantation than in HA-TCP. All these results suggested that in vivo osteogenic potentials in hDPSCs are induced with both HA-TCP and DDM by osteoconduction and osteoinduction, respectively. In addition, transplantation of hDPSCs/DDM might be more effective for differentiation into dentin.

  19. Solar-simulated ultraviolet radiation induces histone 3 methylation changes in the gene promoters of matrix metalloproteinases 1 and 3 in primary human dermal fibroblasts.

    Science.gov (United States)

    Gesumaria, Lisa; Matsui, Mary S; Kluz, Thomas; Costa, Max

    2015-05-01

    Molecular signalling pathways delineating the induction of matrix metalloproteinases (MMPs) by ultraviolet radiation (UVR) are currently well-defined; however, the effects of UVR on epigenetic mechanisms of MMP induction are not as well understood. In this study, we examined solar-simulated UVR (ssUVR)-induced gene expression changes and alterations to histone methylation in the promoters of MMP1 and MMP3 in primary human dermal fibroblasts (HDF). Gene expression changes, including the increased expression of MMP1 and MMP3, were observed using Affymetrix GeneChip arrays and confirmed by qRT-PCR. Using ChIP-PCR, we showed for the first time that in HDF irradiated with 12 J/cm(2) ssUVR, the H3K4me3 transcriptional activating mark increased and the H3K9me2 transcriptional silencing mark decreased in abundance in promoters, correlating with the observed elevation of MMP1 and MMP3 mRNA levels following ssUVR exposure. Changes in mRNA levels due to a single exposure were transient and decreased 5 days after exposure. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. In Vitro and In Vivo Dentinogenic Efficacy of Human Dental Pulp-Derived Cells Induced by Demineralized Dentin Matrix and HA-TCP.

    Science.gov (United States)

    Kang, Kyung-Jung; Lee, Min Suk; Moon, Chan-Woong; Lee, Jae-Hoon; Yang, Hee Seok; Jang, Young-Joo

    2017-01-01

    Human dental pulp cells have been known to have the stem cell features such as self-renewal and multipotency. These cells are differentiated into hard tissue by addition of proper cytokines and biomaterials. Hydroxyapatite-tricalcium phosphates (HA-TCPs) are essential components of hard tissue and generally used as a biocompatible material in tissue engineering of bone. Demineralized dentin matrix (DDM) has been reported to increase efficiency of bone induction. We compared the efficiencies of osteogenic differentiation and in vivo bone formation of HA-TCP and DDM on human dental pulp stem cells (hDPSCs). DDM contains inorganic components as with HA-TCP, and organic components such as collagen type-1. Due to these components, osteoinduction potential of DDM on hDPSCs was remarkably higher than that of HA-TCP. However, the efficiencies of in vivo bone formation are similar in HA-TCP and DDM. Although osteogenic gene expression and bone formation in immunocompromised nude mice were similar levels in both cases, dentinogenic gene expression level was slightly higher in DDM transplantation than in HA-TCP. All these results suggested that in vivo osteogenic potentials in hDPSCs are induced with both HA-TCP and DDM by osteoconduction and osteoinduction, respectively. In addition, transplantation of hDPSCs/DDM might be more effective for differentiation into dentin.

  1. Matrix effects in ion-induced emission as observed in Ne collisions with Cu-Mg and Cu-Al alloys

    Science.gov (United States)

    Ferrante, J.; Pepper, S. V.

    1983-01-01

    Ion induced Auger electron emission is used to study the surfaces of Al, Mg, Cu - 10 at. % Al, Cu - 19.6 at. % Al, and Cu - 7.4 at. % Mg. A neon (Ne) ion beam whose energy is varied from 0.5 to 3 keV is directed at the surface. Excitation of the lighter Ne occurs by the promotion mechanism of Barat and Lichten in asymmetric collisions with Al or Mg atoms. Two principal Auger peaks are observed in the Ne spectrum: one at 22 eV and one at 25 eV. Strong matrix effects are observed in the alloys as a function of energy in which the population of the second peak is greatly enhanced relative to the first over the pure materials. For the pure material over this energy range this ratio is 1.0. For the alloys it can rise to the electronic structure of alloys and to other surface tools such as secondary ion mass spectroscopy.

  2. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells.

    Directory of Open Access Journals (Sweden)

    Zhenya Gao

    Full Text Available All-trans retinoic acid (ATRA plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2 and matrix metalloproteinase 2 (MMP-2 and to explore the signaling pathway of retinoic acid in cultured acute retinal pigment epithelial 19 (ARPE-19 cells.The effects of ATRA (concentrations from 10-9 to 10-5 mol/l on the expression of retinoic acid receptors (RARs in ARPE-19 cells were examined at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR and western blot assay, respectively. The effects of treating ARPE-19 cells with ATRA concentrations ranging from 10-9 to 10-5 mol/l for 24 h and 48 h or with 10-6mol/l ATRA at different times ranging from 6h to 72h were assessed using real-time quantitative PCR (qPCR and enzyme-linked immunosorbent assay (ELISA. The contribution of RARβ-induced activation of ARPE-19 cells was confirmed using LE135, an antagonist of RARβ.RARβ mRNA levels significantly increased in the ARPE-19 cells treated with ATRA for 24h and 48h. These increases in RARβ mRNA levels were dose dependent (at concentrations of 10-9 to 10-5 mol/l with a maximum effect observed at 10-6 mol/l. There were no significant changes in the mRNA levels of RARα and RARγ. Western blot assay revealed that RARβ protein levels were increased significantly in a time-dependent manner in ARPE-19 cells treated with 10-6 mol/l ATRA from 12 h to 72 h, with a marked increase observed at 24 h and 48 h. The upregulation of RARβ and the ATRA-induced secretion in ARPE-19 cells could be inhibited by the RARβ antagonist LE135.ATRA induced upregulation of RARβ in ARPE-19 cells and stimulated these cells to secrete BMP-2 and MMP-2.

  3. 2,3,7,8-Tetrachlorodibenzo-p-dioxin modulates estradiol-induced aldehydic DNA lesions in human breast cancer cells through alteration of CYP1A1 and CYP1B1 expression.

    Science.gov (United States)

    Chen, Shou-Tung; Chen, Dar-Ren; Fang, Ju-Pin; Lin, Po-Hsiung

    2015-05-01

    Many genes responsible for the bioactivation of endogenous estrogen to reactive quinonoid metabolites, including cytochrome P450 (CYP) 1A1, 1A2, and 1B1, are well-known target genes of the aryl hydrocarbon receptor agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The purpose of this research was to investigate the roles of TCDD-mediated altered gene expression in the induction of aldehydic DNA lesions (ADLs) by 17β-estradiol (E2) in human MDA-MB-231 and MCF-7 breast cancer cells. We demonstrated that increases in the number of oxidant-mediated ADLs, including abasic sites and aldehydic base/sugar lesions, were detected in MDA-MB-231 cells exposed to E2. The DNA-damaging effects of E2 in MDA-MB-231 cells were prevented by pretreatment of cells with TCDD. In contrast, we did not observe statistically significant increases in the number of ADLs in MCF-7 cells exposed to E2. However, with TCDD pretreatment, an approximately twofold increase in the number of ADLs was detected in MCF-7 cells exposed to E2. TCDD pretreatment induces disparity in the disposition of E2 to reactive quinonoid metabolites and the subsequent formation of oxidative DNA lesions through alteration of CYP1A1 and CYP1B1 expression in human breast cancer cells.

  4. Histopathological, Ultrastructural, and Immunohistochemical Assessment of Hippocampus Structures of Rats Exposed to TCDD and High Doses of Tocopherol and Acetylsalicylic Acid

    Directory of Open Access Journals (Sweden)

    Joanna Rosińczuk

    2015-01-01

    Full Text Available The effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD on central nervous system consists of changing expression of estrogen receptors, whereas the result of chronic inflammatory reaction caused by dioxin is occurrence of destructive changes in various organs connected with disturbed metabolism of connective tissue and damage of cells. The aim of the study was to determine the effect of dioxins on function, ultrastructure, and cytological and histological structure of hippocampus, particularly on expression of estrogen receptors in central nervous system as well as to define protective influence of tocopherol (TCP and acetylsalicylic acid (ASA on the decrease in activity of proinflammatory effects in central nervous system. It was shown that TCDD contributes to destructive and inflammatory changes along with demyelization of myelin sheaths and atrophy of estrogen receptors in hippocampus. Dioxin contributes to atrophy of estrogen receptors in hippocampus, in which also destructive and inflammatory changes were found along with demyelination of myelin sheaths. Histopathological and ultrastructural image of hippocampus areas in rats, in which both TCP and ASA were used, is characterized by poorly expressed degenerative changes and smaller inflammatory reactivity. Using both TCP and ASA has a protective effect on functions of central nervous system.

  5. Identification of Serine Conformers by Matrix-Isolation IR Spectroscopy Aided by Near-Infrared Laser-Induced Conformational Change, 2D Correlation Analysis, and Quantum Mechanical Anharmonic Computations.

    Science.gov (United States)

    Najbauer, Eszter E; Bazsó, Gábor; Apóstolo, Rui; Fausto, Rui; Biczysko, Malgorzata; Barone, Vincenzo; Tarczay, György

    2015-08-20

    The conformers of α-serine were investigated by matrix-isolation IR spectroscopy combined with NIR laser irradiation. This method, aided by 2D correlation analysis, enabled unambiguously grouping the spectral lines to individual conformers. On the basis of comparison of at least nine experimentally observed vibrational transitions of each conformer with empirically scaled (SQM) and anharmonic (GVPT2) computed IR spectra, six conformers were identified. In addition, the presence of at least one more conformer in Ar matrix was proved, and a short-lived conformer with a half-life of (3.7 ± 0.5) × 10(3) s in N2 matrix was generated by NIR irradiation. The analysis of the NIR laser-induced conversions revealed that the excitation of the stretching overtone of both the side chain and the carboxylic OH groups can effectively promote conformational changes, but remarkably different paths were observed for the two kinds of excitations.

  6. Matrix analysis

    CERN Document Server

    Bhatia, Rajendra

    1997-01-01

    A good part of matrix theory is functional analytic in spirit. This statement can be turned around. There are many problems in operator theory, where most of the complexities and subtleties are present in the finite-dimensional case. My purpose in writing this book is to present a systematic treatment of methods that are useful in the study of such problems. This book is intended for use as a text for upper division and gradu­ ate courses. Courses based on parts of the material have been given by me at the Indian Statistical Institute and at the University of Toronto (in collaboration with Chandler Davis). The book should also be useful as a reference for research workers in linear algebra, operator theory, mathe­ matical physics and numerical analysis. A possible subtitle of this book could be Matrix Inequalities. A reader who works through the book should expect to become proficient in the art of deriving such inequalities. Other authors have compared this art to that of cutting diamonds. One first has to...

  7. Cytochrome P4501A1 is Required for Vascular Dysfunction and Hypertension Induced by 2,3,7,8-Tetrachlorodibenzo-p-dioxin

    Science.gov (United States)

    National Health and Nutrition Examination Survey data show an association between hypertension and exposure to dioxin-like halogenated aromatic hydrocarbons (HAH). Further, chronic exposure of mice to the prototypical HAH, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), induces reactive oxygen species (...

  8. Matrix-induced autologous chondrocyte implantation of the knee: mid-term and long-term follow-up by MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Genovese, Eugenio; Angeretti, Maria Gloria; Leonardi, Anna; Callegari, Leonardo; Fugazzola, Carlo [Insubria University, Department of Radiology, Varese (Italy); Ronga, Mario [Insubria University, Department of Orthopaedics and Traumatology, Varese (Italy); Novario, Raffaele [Insubria University, Department of Clinical and Biological Sciences, Varese (Italy); Albrizio, Mauro [Pavia University, Department of Radiology, Pavia (Italy)

    2011-01-15

    To define magnetic resonance (MR) arthrography imaging findings of matrix-induced autologous chondrocyte implantation (MACI) grafts of the knee in order to describe implant behaviour and to compare findings with validated clinical scores 30 and 60 months after MACI implant. Thirteen patients were recruited (10 male, 3 female) with a total number of 15 chondral lesions. Each patient underwent an MACI procedure and MR arthrography 30 and 60 months after surgery. MR arthrography was performed using a dedicated coil with a 1.5-Tesla unit. The status of the chondral implant was evaluated with the modified MOCART scoring scale. The lining of the implant, the integration to the border zone, the surface and structure of the repaired tissue were assessed, and the presence of bone marrow oedema and effusion was evaluated. For clinical assessment, the Cincinnati score was used. At 60 months, the abnormality showed worsening in 1 out of 15 cases. Integration showed improvement in 3 out of 15 cases, and worsening in 3 out of 15 cases. Two surfaces of the implant showed further deterioration at 60 months, and 1 afflicted implant fully recovered after the same time interval. Implant contrast enhancement at 30 months was seen in 2 out of 15 cases, 1 of which recovered at 60 months. According to the MOCART score, 4 cases were rated 68.4 out of 75 at 30 months and 65 out of 75 at 60 months. The mean clinical score decreased from 8.6 out of 10 at 30 months to 8.1 out of 10 at 60 months. Magnetic resonance arthrography improved the evaluation of implants and facilitated the characterisation of MACI integration with contiguous tissues. The follow-up showed significant changes in MACI, even at 60 months, allowing for useful long-term MR evaluations. (orig.)

  9. Effect of Tissue-Culture Substratum and Extracellular Matrix Overlay on Liver-Selective and Xenobiotic Inducible Gene Expression in Primary Rat Hepatocytes

    Science.gov (United States)

    SIDHU, J.S.; FARIN, F.M.; KAVANAGH, T.J.; OMIECINSKI, C.J.

    2012-01-01

    In a previous study (Sidhu et al., 1993), we demonstrated that a combination of certain cell culture media, hormone addition, and extracellular matrix (ECM) overlay coordinately modulated the expression of certain liver-selective genes in primary rat hepatocyte cultures, including the responsiveness of genes to phenobarbital. However, little is known about the interactions between the type of substratum upon which hepatocytes are adhered and the ECM overlay, as codeterminants of liver-selective gene expression. The present study was undertaken to compare specific substrata, including tissue culture-grade plastic, Primaria, and type 1 collagen-coated plastic, in combination with the presence or absence of standard ECM or a growth-factor-reduced ECM overlay. Hepatocyte cultures were assessed either as control cultures or subsequent to treatment for 24 h with phenobarbital (0.1 or 1 mM), or beta-naphthoflavone (22 μM), to monitor responses of hepatocytes to two prototypic gene-inducing agents. Analyses of maintenance and induction of cytochrome P450 and liver-selective gene expression included measures of mRNA levels using Northern blot and slot-blot hybridization and single cell immunofluorescence assays to measure levels of specific cytochrome P450 proteins. The results of these experiments demonstrated that hepatocyte-selective expression, including the absolute level of induction response (relative to those observed in the rat liver in vivo) was highly dependent on the presence of ECM overlay but independent of the substratum employed. As studied herein, the establishment of optimal conditions for primary hepatocyte culture, enabling reproduction of responses observed in vivo, is important to further prospects for in vitro toxicity testing and for investigating molecular mechanisms of phenobarbital-mediated gene regulation. PMID:24817786

  10. Gene expression profiling of fixed tissues identified hypoxia-inducible factor-1α, VEGF, and matrix metalloproteinase-2 as biomarkers of lymph node metastasis in hepatocellular carcinoma.

    Science.gov (United States)

    Xiang, Zuo-Lin; Zeng, Zhao-Chong; Fan, Jia; Tang, Zhao-You; Zeng, Hai-Ying; Gao, Dong-Mei

    2011-08-15

    Hepatocellular carcinoma (HCC) most often develops in patients infected with hepatitis B or hepatitis C virus. Differential gene expression profiling is useful for investigating genes associated with lymph node metastasis (LNM). We screened genes to identify potential biomarkers for LNM in HCC. RNA was extracted from formalin-fixed specimens of paired intratumoral and peritumoral tissues of patients with lymph node-positive (n = 36) or negative (n = 36) HCC. A cDNA-mediated annealing, selection, extension, and ligation assay was done with an array of 502 known cancer-related genes to identify differentially expressed genes in 20 pairs of patients with or without LNM. Candidate biomarkers were evaluated by using immunohistochemistry and tissue microarrays in an independent cohort of 309 HCC patients who had undergone hepatectomy. Of the 309 patients, 235 (76.1%) patients were infected with hepatitis B. Compared with lymph node-negative patients, lymph node-positive patients had 17 overexpressed genes and 19 underexpressed genes in intratumoral tissues, and 25 overexpressed genes and 22 underexpressed genes in peritumoral tissues. Hypoxia-inducible factor (HIF)-1α, VEGF, and matrix metalloproteinase (MMP)-2 were selected for analysis in the cohort of 309 HCC patients. We found that intratumoral protein levels of HIF-1α, VEGF, and MMP-2 were independent risk factors for developing LNM. We identified 83 cancer genes that were differentially expressed in lymph node-positive and lymph node-negative HCC. Our findings show that the combination of intratumoral HIF-1α, VEGF, and MMP-2 may be useful as a molecular prediction model for LNM. ©2011 AACR.

  11. Protective effect of Calendula officinalis extract against UVB-induced oxidative stress in skin: evaluation of reduced glutathione levels and matrix metalloproteinase secretion.

    Science.gov (United States)

    Fonseca, Yris Maria; Catini, Carolina Dias; Vicentini, Fabiana T M C; Nomizo, Auro; Gerlach, Raquel Fernanda; Fonseca, Maria José Vieira

    2010-02-17

    Calendula officinalis flowers have long been employed time in folk therapy, and more than 35 properties have been attributed to decoctions and tinctures from the flowers. The main uses are as remedies for burns (including sunburns), bruises and cutaneous and internal inflammatory diseases of several origins. The recommended doses are a function both of the type and severity of the condition to be treated and the individual condition of each patient. Therefore, the present study investigated the potential use of Calendula officinalis extract to prevent UV irradiation-induced oxidative stress in skin. Firstly, the physico-chemical composition of marigold extract (ME) (hydroalcoholic extract) was assessed and the in vitro antioxidant efficacy was determined using different methodologies. Secondly, the cytotoxicity was evaluated in L929 and HepG2 cells with the MTT assay. Finally, the in vivo protective effect of ME against UVB-induced oxidative stress in the skin of hairless mice was evaluated by determining reduced glutathione (GSH) levels and monitoring the secretion/activity of metalloproteinases. The polyphenol, flavonoid, rutin and narcissin contents found in ME were 28.6 mg/g, 18.8 mg/g, 1.6 mg/g and 12.2mg/g, respectively and evaluation of the in vitro antioxidant activity demonstrated a dose-dependent effect of ME against different radicals. Cytoxicity experiments demonstrated that ME was not cytotoxic for L929 and HepG2 cells at concentrations less than or equal to of 15 mg/mL. However, concentrations greater than or equal to 30 mg/mL, toxic effects were observed. Finally, oral treatment of hairless mice with 150 and 300 mg/kg of ME maintained GSH levels close to non-irradiated control mice. In addition, this extract affects the activity/secretion of matrix metalloproteinases 2 and 9 (MMP-2 and -9) stimulated by exposure to UVB irradiation. However, additional studies are required to have a complete understanding of the protective effects of ME for skin

  12. [The role of disequilibrium of expression of matrix metalloproteinase-2/9 and their tissue inhibitors in pathogenesis of hyperoxia-induced acute lung injury in mice].

    Science.gov (United States)

    Zhang, Xiang-feng; Zhu, Guang-fa; Liu, Shuang; Foda, Hussein D

    2008-10-01

    To investigate the role of matrix metalloproteinase-2/9 (MMP-2/9) and their tissue inhibitors (TIMP-1/2) in pathogenesis of acute lung injury (ALI) induced by hyperoxia. Seventy-two C57BL/6 mice were randomly divided into normal control group, hyperoxia for 24 hours group, hyperoxia for 48 hours group, and hyperoxia for 72 hours group, with 18 mice in each group. The mice in hyperoxia groups were exposed to >98% oxygen in sealed cages, and the normal control group were placed outside of the cage to breathe room air. At the end of the exposure time the animals were euthanized, the right lung was removed and phosphate buffer solution (PBS) was used to lavage the lung through the endotracheal catheter. The wet/dry weight ratio, broncho-alveolar lavage fluid (BALF) protein content and the volume of pleural fluid were measured, the severity of lung injury was assessed; the expression of MMP-2/9 and TIMP-1/2 mRNA in lung tissue at 24, 48 and 72 hours of hyperoxia were assessed by reverse transcript-polymerase chain reaction (RT-PCR); the amount of MMP-2/9 and TIMP-1/2 protein in lung tissue were measured by enzyme-linked immunosorbent assay (ELISA). Hyperoxia caused ALI as evidenced by the increase in lung wet/dry weight ratio, BALF protein content and the volume of pleural fluid as compared with the normal control group (P<0.05 or P<0.01). RT-PCR study showed increased expression of MMP-2/9 and TIMP-1 mRNA in lung tissues (P<0.05 or P<0.01), and ELISA assay also demonstrated upregulation of MMP-2/9 and an increase in TIMP-1 amount in BALF compared with their normal control group (P<0.05 or P<0.01). The ratios of both MMP-2 mRNA/TIMP-2 mRNA and MMP-2 protein/TIMP-2 protein were all increased in hyperoxia groups as compared with their normal control group (all P<0.01). Hyperoxia causes ALI in mice, and disturbance of MMP-2/TIMP-2 balance plays an important role in the development of hyperoxia-induced ALI in mice.

  13. Matrix pentagons

    Science.gov (United States)

    Belitsky, A. V.

    2017-10-01

    The Operator Product Expansion for null polygonal Wilson loop in planar maximally supersymmetric Yang-Mills theory runs systematically in terms of multi-particle pentagon transitions which encode the physics of excitations propagating on the color flux tube ending on the sides of the four-dimensional contour. Their dynamics was unraveled in the past several years and culminated in a complete description of pentagons as an exact function of the 't Hooft coupling. In this paper we provide a solution for the last building block in this program, the SU(4) matrix structure arising from internal symmetry indices of scalars and fermions. This is achieved by a recursive solution of the Mirror and Watson equations obeyed by the so-called singlet pentagons and fixing the form of the twisted component in their tensor decomposition. The non-singlet, or charged, pentagons are deduced from these by a limiting procedure.

  14. Matrix pentagons

    Directory of Open Access Journals (Sweden)

    A.V. Belitsky

    2017-10-01

    Full Text Available The Operator Product Expansion for null polygonal Wilson loop in planar maximally supersymmetric Yang–Mills theory runs systematically in terms of multi-particle pentagon transitions which encode the physics of excitations propagating on the color flux tube ending on the sides of the four-dimensional contour. Their dynamics was unraveled in the past several years and culminated in a complete description of pentagons as an exact function of the 't Hooft coupling. In this paper we provide a solution for the last building block in this program, the SU(4 matrix structure arising from internal symmetry indices of scalars and fermions. This is achieved by a recursive solution of the Mirror and Watson equations obeyed by the so-called singlet pentagons and fixing the form of the twisted component in their tensor decomposition. The non-singlet, or charged, pentagons are deduced from these by a limiting procedure.

  15. Matrix metalloproteinase-2 and -9 are induced differently by metal nanoparticles in human monocytes: The role of oxidative stress and protein tyrosine kinase activation

    International Nuclear Information System (INIS)

    Wan Rong; Mo Yiqun; Zhang Xing; Chien Sufan; Tollerud, David J.; Zhang Qunwei

    2008-01-01

    Recently, many studies have shown that nanoparticles can translocate from the lungs to the circulatory system. As a particulate foreign body, nanoparticles could induce host responses such as reactive oxygen species (ROS) generation, inflammatory cytokine and matrix metalloproteinase (MMP) release which play a major role in tissue destruction and remodeling. However, the direct effects of nanoparticles on leukocytes, especially monocytes, are still unclear. The objective of the present study was to compare the ability of Nano-Co and Nano-TiO 2 to cause alteration of transcription and activity of MMPs and to explore possible mechanisms. We hypothesized that non-toxic doses of some transition metal nanoparticles stimulate an imbalance of MMP/TIMP that cause MMP production that may contribute to their health effects. To test this hypothesis, U937 cells were treated with Nano-Co and Nano-TiO 2 and cytotoxic effects and ROS generation were measured. The alteration of MMP-2 and MMP-9 expression and activity of MMP-2 and MMP-9 after exposure to these metal nanoparticles were subsequently determined. To investigate the potential signaling pathways involved in the Nano-Co-induced MMP activation, the ROS scavengers or inhibitors, AP-1 inhibitor, and protein tyrosine kinase (PTK) inhibitors were also used to pre-treat U937 cells. Our results demonstrated that exposure of U937 cells to Nano-Co, but not to Nano-TiO 2 , at a dose that does not cause cytotoxicity, resulted in ROS generation and up-regulation of MMP-2 and MMP-9 mRNA expression .. Our results also showed dose- and time-related increases in pro-MMP-2 and pro-MMP-9 gelatinolytic activities in conditioned media after exposure of U937 cells to Nano-Co, but not to Nano-TiO 2 . Nano-Co-induced pro-MMP-2 and pro-MMP-9 activity increases were inhibited by pre-treatment with ROS scavengers or inhibitors. We also demonstrated dose- and time-related decreases in tissue inhibitors of metalloproteinases 2 (TIMP-2) in U937 cells

  16. INFLUENCE OF TYPE II DIABETES, OBESITY, AND EXPOSURE TO 2, 3, 7, 8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) EXPOSURE ON THE EXPRESSION OF HEPATIC CYP1A2 IN A MURIN MODEL OF TYPE II DIABETES

    Science.gov (United States)

    Influence of type II diabetes, obesity and exposure 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure on the expression of hepatic CYPIA2 in a murine model of type II diabetes. SJ Godin', VM Richardson2, JJ Diliberto2, LS Birnbaum', MJ DeVito2; 'Curriculum In Toxicology, UNC-CH...

  17. Compound- and sex-specific effects on programming of energy and immune homeostasis in adult C57BL/6JxFVB mice after perinatal TCDD and PCB 153

    International Nuclear Information System (INIS)

    Esterik, J.C.J. van; Verharen, H.W.; Hodemaekers, H.M.; Gremmer, E.R.; Nagarajah, B.; Kamstra, J.H.; Dollé, M.E.T.; Legler, J.; Ven, L.T.M. van der

    2015-01-01

    Early life exposure to endocrine disrupting compounds has been linked to chronic diseases later in life, like obesity and related metabolic disorders. We exposed C57BL/6JxFVB hybrid mice to the aryl hydrocarbon receptor agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the constitutive androstane receptor/pregnane X receptor agonist polychlorinated biphenyl 153 (PCB 153) in an experimental design relevant for human exposure. Exposure occurred during gestation and lactation via maternal feed to a wide dose range (TCDD: 10–10,000 pg/kg body weight/day; PCB 153: 0.09–1406 μg/kg body weight/d). Then exposure was ceased and offspring were followed up to 1 year of age. Metabolic parameters like body weight, fat pad weights, glucose tolerance, endocrine serum profile, and neurobehavioral and immunological parameters were determined. Body weight was transiently affected by both compounds throughout the follow-up. TCDD-exposed males showed decreased fat pad and spleen weights and an increase in IL-4 production of splenic immune cells. In contrast, females showed increased fat pad weights and production of IFNγ. PCB 153-exposed males showed an increase in glucose, whereas females showed an increase in glucagon, a decrease in pancreas weight, and an increase in thymus weight. In conclusion, early life exposure to TCDD appears to affect programming of energy and immune homeostasis in offspring, whereas the effects of perinatal PCB 153 were mainly on programming of glucose homeostasis. Both compounds act sex-specifically. Lowest derived BMDLs (lower bounds of the (two sided) 90%-confidence interval for the benchmark dose) for both compounds are not lower than current tolerable daily intakes. - Highlights: • Early life exposure to TCDD affects programming of energy and immune homeostasis. • Early life exposure to PCB 153 affects programming of energy homeostasis. • Both compounds act sex-specifically. • Lowest derived BMDLs for both TCDD and PCB 153 are not

  18. The effect of a single nucleotide polymorphism in the matrix metalloproteinase-1 (MMP-1) promoter on force-induced MMP-1 expression in human periodontal ligament cells

    NARCIS (Netherlands)

    Huang, Sheng-Fu; Li, Yu-Hong; Ren, Yi-Jin; Cao, Zheng-Guo; Long, Xing

    Matrix metalloproteinase-1 (MMP-1) 1G/2G (-1,607) polymorphisms have been identified and shown to influence the transcription of the MMP-1 gene. In order to compare the expression of MMP-1 with different MMP-1 gene promoter alleles after force loading, human periodontal ligament (PDL) cells were

  19. Cytokine-induced endogenous procollagenase stored in the extracellular matrix of soft connective tissue results in a burst of collagen breakdown following its activation

    NARCIS (Netherlands)

    van der Zee, E.; Everts, V.; Beertsen, W.

    1996-01-01

    Numerous data strongly suggest the involvement of cytokines and the matrix metalloproteinase collagenase (MMP-1) in the pathogenesis of periodontitis. Recently, we have demonstrated that, upon culturing under the influence of IL-1 alpha + EGF, a large amount of inactive procollagenase (MMP-1) is

  20. Human galectins induce conversion of dermal fibroblasts into myofibroblasts and production of extracellular matrix: potential application in tissue engineering and wound repair

    Czech Academy of Sciences Publication Activity Database

    Dvořánková, B.; Szabo, P.; Lacina, L.; Gál, P.; Uhrová, J.; Zima, T.; Kaltner, H.; André, S.; Gabius, H. J.; Syková, Eva; Smetana Jr., K.

    2011-01-01

    Roč. 194, č. 6 (2011), s. 469-480 ISSN 1422-6405 Grant - others:GA MŠk(CZ) 1M0538 Program:1M Institutional research plan: CEZ:AV0Z50390703 Keywords : extracellular matrix * fibronectin * keratinocyte Subject RIV: FH - Neurology Impact factor: 2.203, year: 2011

  1. The methylotrophic yeast Hansenula polymorpha contains an inducible import pathway for peroxisomal matrix proteins with an N-terminal targeting signal (PTS2 proteins)

    NARCIS (Netherlands)

    Faber, Klaas Nico; Haima, Pieter; Gietl, Christine; Harder, Willem; Ab, Geert; Veenhuis, Marten

    1994-01-01

    Two main types of peroxisomal targeting signals have been identified that reside either at the extreme C terminus (PTS1) or the N terminus (PTS2) of the protein. In the methylotrophic yeast Hansenula polymorpha the majority of peroxisomal matrix proteins are of the PTS1 type. Thus far, for H.

  2. A survey of matrix theory and matrix inequalities

    CERN Document Server

    Marcus, Marvin

    2010-01-01

    Written for advanced undergraduate students, this highly regarded book presents an enormous amount of information in a concise and accessible format. Beginning with the assumption that the reader has never seen a matrix before, the authors go on to provide a survey of a substantial part of the field, including many areas of modern research interest.Part One of the book covers not only the standard ideas of matrix theory, but ones, as the authors state, ""that reflect our own prejudices,"" among them Kronecker products, compound and induced matrices, quadratic relations, permanents, incidence

  3. Resistance training improves body composition and increases matrix metalloproteinase 2 activity in biceps and gastrocnemius muscles of diet-induced obese rats.

    Science.gov (United States)

    Souza, Markus Vinicius Campos; Leite, Richard Diego; Souza Lino, Anderson Diogo de; Marqueti, Rita de Cássia; Bernardes, Celene Fernandes; Araújo, Heloisa Sobreiro Selistre de; Bouskela, Eliete; Bouskella, Eliete; Shiguemoto, Gilberto Eiji; Andrade Perez, Sérgio Eduardo de; Kraemer-Aguiar, Luiz Guilherme

    2014-01-01

    We investigated the influence of resistance training on body composition and matrix metalloproteinase 2 activity in skeletal muscles of rats fed a high-fat diet. Thirty-two Wistar rats were divided into four experimental groups (n = 8/each) according to diet and exercise status: Control (standard diet), Obese Control (high-fat diet), Resistance Training (standard diet) and Obese Resistance Training (high-fat diet) groups. Animals were fed a high-fat diet for 12 weeks to promote excessive weight gain. Resistance Training groups performed 12 weeks of training periods after this period in a vertical ladder three times/week. Fat percentage, fat-free mass and fat mass were assessed using dual-energy X-ray absorptiometry, and matrix metalloproteinase 2 activity in biceps and gastrocnemius muscles was analyzed using zymography. Resistance training significantly reduced body and fat masses and fat percentages in both trained groups (pmuscles of both trained groups (pmuscle matrix metalloproteinase 2 activity promoted by excessive weight gain were positively modified by resistance training.

  4. Correntropy Based Matrix Completion

    Directory of Open Access Journals (Sweden)

    Yuning Yang

    2018-03-01

    Full Text Available This paper studies the matrix completion problems when the entries are contaminated by non-Gaussian noise or outliers. The proposed approach employs a nonconvex loss function induced by the maximum correntropy criterion. With the help of this loss function, we develop a rank constrained, as well as a nuclear norm regularized model, which is resistant to non-Gaussian noise and outliers. However, its non-convexity also leads to certain difficulties. To tackle this problem, we use the simple iterative soft and hard thresholding strategies. We show that when extending to the general affine rank minimization problems, under proper conditions, certain recoverability results can be obtained for the proposed algorithms. Numerical experiments indicate the improved performance of our proposed approach.

  5. OASIS/CREB3L1 is induced by endoplasmic reticulum stress in human glioma cell lines and contributes to the unfolded protein response, extracellular matrix production and cell migration.

    Directory of Open Access Journals (Sweden)

    Ravi N Vellanki

    Full Text Available OASIS is a transcription factor similar to ATF6 that is activated by endoplasmic reticulum stress. In this study we investigated the expression of OASIS in human glioma cell lines and the effect of OASIS knock-down on the ER stress response and cell migration. OASIS mRNA was detected in three distinct glioma cell lines (U373, A172 and U87 and expression levels were increased upon treatment with ER stress-inducing compounds in the U373 and U87 lines. OASIS protein, which is glycosylated on Asn-513, was detected in the U373 and U87 glioma lines at low levels in control cells and protein expression was induced by ER stress. Knock-down of OASIS in human glioma cell lines resulted in an attenuated unfolded protein response to ER stress (reduced GRP78/BiP and GRP94 induction and decreased expression of chondroitin sulfate proteoglycan extracellular matrix proteins, but induction of the collagen gene Col1a1 was unaffected. Cells in which OASIS was knocked-down exhibited altered cell morphology and reduced cell migration. These results suggest that OASIS is important for the ER stress response and maintenance of some extracellular matrix proteins in human glioma cells.

  6. The influence of type I diabetes mellitus on the expression and activity of gelatinases (matrix metalloproteinases-2 and -9) in induced periodontal disease.

    Science.gov (United States)

    Silva, J A F; Lorencini, M; Peroni, L A; De La Hoz, C L R; Carvalho, H F; Stach-Machado, D R

    2008-02-01

    Periodontal disease corresponds to a group of lesions that affect the tooth-supporting tissues present in the dental follicle. Although bacterial plaque is important, the immune response also contributes to the destruction of periodontal tissues. Diabetes mellitus is closely associated with the development, progression and severity of periodontal disease because it not only affects extracellular matrix organization but also the tissue response to inflammation. The objective of the present investigation was to study the influence of diabetes on experimental periodontal disease by evaluating the degradation of extracellular matrix through the analysis of matrix metalloproteinase (MMP)-2 and MMP-9 expression and activity, using immunofluorescence, zymography and real-time reverse transcription-polymerase chain reaction. Wistar rats were divided into normal and diabetic groups and evaluated 0, 15 and 30 d after the induction of periodontal disease by ligature. MMP-2 and -9 were detected in epithelial cells, in the blood vessel endothelium and in connective tissue cells. The same profile of enzymatic expression of MMP-2 and -9 was observed in normal and diabetic animals, with a peak in activity at day 15 of inflammation. However, in diabetic animals, MMP-2 gelatinolytic activity was reduced after the inflammatory stimulus, whereas that of MMP-9 was increased. MMP-2 gene expression decreased with inflammation in both normal groups and groups with diabetes. In contrast, MMP-9 expression increased in normal animals and decreased in diabetic animals after inflammation. The results suggest the involvement of MMP-2 and -9 in the dynamics of periodontal disease and that variation in their expression levels results in differences in tissue organization and wound healing in normal and diabetic animals.

  7. Lung tissue remodelling in MCT-induced pulmonary hypertension: a proposal for a novel scoring system and changes in extracellular matrix and fibrosis associated gene expression

    Science.gov (United States)

    Franz, Marcus; Grün, Katja; Betge, Stefan; Rohm, Ilonka; Ndongson-Dongmo, Bernadin; Bauer, Reinhard; Schulze, P. Christian; Lichtenauer, Michael; Petersen, Iver; Neri, Dario; Berndt, Alexander; Jung, Christian

    2016-01-01

    Pulmonary hypertension (PH) is associated with vasoconstriction and remodelling. We studied lung tissue remodelling in a rat model of PH with special focus on histology and extracellular matrix (ECM) remodelling. After induction of PH by monocrotaline, lung tissue was analysed histologically, by gene expression analysis and immunofluorescence labelling of ED-A domain containing fibronectin (ED-A+ Fn), B domain containing tenascin-C (B+ Tn-C) as well as alpha-smooth muscle actin (α-SMA). Serum concentrations of ED-A+ Fn were determined by ELISA. Systolic right ventricular pressure (RVPsys) values were significantly elevated in PH (n = 18; 75 ± 26.4 mmHg) compared to controls (n = 10; 29 ± 19.3 mmHg; p = 0.015). The histological sum-score was significantly increased in PH (8.0 ± 2.2) compared to controls (2.5 ± 1.6; p < 0.001). Gene expression analysis revealed relevant induction of several key genes of extracellular matrix remodelling. Increased protein deposition of ED-A+ Fn but not of B+ Tn-C and α-SMA in lung tissue was found in PH (2.88 ± 3.19 area%) compared to controls (1.32 ± 0.16 area%; p = 0.030). Serum levels of ED-A+ Fn were significantly higher in PH (p = 0.007) positively correlating with RVPsys (r = 0.618, p = 0.019). We here present a novel histological scoring system to assess lung tissue remodelling in PH. Gene expression analysis revealed induction of candidate genes involved in collagen matrix turnover, fibrosis and vascular remodelling. The stable increased tissue deposition of ED-A+ Fn in PH as well as its dynamics in serum suggests a role as a promising novel biomarker and potential therapeutic target. PMID:27835899

  8. CO-releasing molecules CORM2 attenuates angiotensin II-induced human aortic smooth muscle cell migration through inhibition of ROS/IL-6 generation and matrix metalloproteinases-9 expression

    Directory of Open Access Journals (Sweden)

    Ming-Horng Tsai

    2017-08-01

    Full Text Available Ang II has been involved in the pathogenesis of cardiovascular diseases, and matrix metalloproteinase-9 (MMP-9 induced migration of human aortic smooth muscle cells (HASMCs is the most common and basic pathological feature. Carbon monoxide (CO, a byproduct of heme breakdown by heme oxygenase, exerts anti-inflammatory effects in various tissues and organ systems. In the present study, we aimed to investigate the effects and underlying mechanisms of carbon monoxide releasing molecule-2 (CORM-2 on Ang II-induced MMP-9 expression and cell migration of HASMCs. Ang II significantly up-regulated MMP-9 expression and cell migration of HASMCs, which was inhibited by transfection with siRNA of p47phox, Nox2, Nox4, p65, angiotensin II type 1 receptor (AT1R and pretreatment with the inhibitors of NADPH oxidase, ROS, and NF-κB. In addition, Ang II also induced NADPH oxidase/ROS generation and p47phox translocation from the cytosol to the membrane. Moreover, Ang II-induced oxidative stress and MMP-9-dependent cell migration were inhibited by pretreatment with CORM-2. Finally, we observed that Ang II induced IL-6 release in HASMCs via AT1R, but not AT2R, which could further caused MMP-9 secretion and cell migration. Pretreatment with CORM-2 reduced Ang II-induced IL-6 release. In conclusion, CORM-2 inhibits Ang II-induced HASMCs migration through inactivation of suppression of NADPH oxidase/ROS generation, NF-κB inactivation and IL-6/MMP-9 expression. Thus, application of CO, especially CORM-2, is a potential countermeasure to reverse the pathological changes of various cardiovascular diseases. Further effects aimed at identifying novel antioxidant and anti-inflammatory substances protective for heart and blood vessels that targeting CO and establishment of well-designed in vivo models properly evaluating the efficacy of these agents are needed.

  9. Efficiency criterion for teleportation via channel matrix, measurement matrix and collapsed matrix

    Directory of Open Access Journals (Sweden)

    Xin-Wei Zha

    Full Text Available In this paper, three kinds of coefficient matrixes (channel matrix, measurement matrix, collapsed matrix associated with the pure state for teleportation are presented, the general relation among channel matrix, measurement matrix and collapsed matrix is obtained. In addition, a criterion for judging whether a state can be teleported successfully is given, depending on the relation between the number of parameter of an unknown state and the rank of the collapsed matrix. Keywords: Channel matrix, Measurement matrix, Collapsed matrix, Teleportation

  10. Extended biorthogonal matrix polynomials

    Directory of Open Access Journals (Sweden)

    Ayman Shehata

    2017-01-01

    Full Text Available The pair of biorthogonal matrix polynomials for commutative matrices were first introduced by Varma and Tasdelen in [22]. The main aim of this paper is to extend the properties of the pair of biorthogonal matrix polynomials of Varma and Tasdelen and certain generating matrix functions, finite series, some matrix recurrence relations, several important properties of matrix differential recurrence relations, biorthogonality relations and matrix differential equation for the pair of biorthogonal matrix polynomials J(A,B n (x, k and K(A,B n (x, k are discussed. For the matrix polynomials J(A,B n (x, k, various families of bilinear and bilateral generating matrix functions are constructed in the sequel.

  11. A matrix lower bound

    Energy Technology Data Exchange (ETDEWEB)

    Grcar, Joseph F.

    2002-02-04

    A matrix lower bound is defined that generalizes ideas apparently due to S. Banach and J. von Neumann. The matrix lower bound has a natural interpretation in functional analysis, and it satisfies many of the properties that von Neumann stated for it in a restricted case. Applications for the matrix lower bound are demonstrated in several areas. In linear algebra, the matrix lower bound of a full rank matrix equals the distance to the set of rank-deficient matrices. In numerical analysis, the ratio of the matrix norm to the matrix lower bound is a condition number for all consistent systems of linear equations. In optimization theory, the matrix lower bound suggests an identity for a class of min-max problems. In real analysis, a recursive construction that depends on the matrix lower bound shows that the level sets of continuously differential functions lie asymptotically near those of their tangents.

  12. Matrix completion by deep matrix factorization.

    Science.gov (United States)

    Fan, Jicong; Cheng, Jieyu

    2018-02-01

    Conventional methods of matrix completion are linear methods that are not effective in handling data of nonlinear structures. Recently a few researchers attempted to incorporate nonlinear techniques into matrix completion but there still exists considerable limitations. In this paper, a novel method called deep matrix factorization (DMF) is proposed for nonlinear matrix completion. Different from conventional matrix completion methods that are based on linear latent variable models, DMF is on the basis of a nonlinear latent variable model. DMF is formulated as a deep-structure neural network, in which the inputs are the low-dimensional unknown latent variables and the outputs are the partially observed variables. In DMF, the inputs and the parameters of the multilayer neural network are simultaneously optimized to minimize the reconstruction errors for the observed entries. Then the missing entries can be readily recovered by propagating the latent variables to the output layer. DMF is compared with state-of-the-art methods of linear and nonlinear matrix completion in the tasks of toy matrix completion, image inpainting and collaborative filtering. The experimental results verify that DMF is able to provide higher matrix completion accuracy than existing methods do and DMF is applicable to large matrices. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Heavy ion induced damage in MgAl sub 2 O sub 4 , an inert matrix candidate for the transmutation of minor actinides

    CERN Document Server

    Wiss, T

    1999-01-01

    Magnesium aluminum spinel (MgAl sub 2 O sub 4) is a material selected as a possible matrix for transmutation of minor actinides by neutron capture or fission in nuclear reactors. To study the radiation stability of this inert matrix, especially against fission product impact, irradiations with heavy energetic ions or clusters have been performed. The high electronic energy losses of the heavy ions in this material led to the formation of visible tracks as evidenced by transmission electron microscopy for 30 MeV C sub 6 sub 0 -Buckminster fullerenes and for ions of energy close to or higher than fission energy ( sup 2 sup 0 sup 9 Bi with 120 MeV and 2.38 GeV energy). The irradiations at high energies showed a pronounced degradation of the spinel. Additionally, MgAl sub 2 O sub 4 exhibited a large swelling for irradiation at high fluences with fission products of fission energy (here I-ions of 72 MeV) and at temperatures <= 500 deg. C. These observations are discussed from the technological point of view in ...

  14. Matrix-M Adjuvated Seasonal Virosomal Influenza Vaccine Induces Partial Protection in Mice and Ferrets against Avian H5 and H7 Challenge.

    Directory of Open Access Journals (Sweden)

    Freek Cox

    Full Text Available There is a constant threat of zoonotic influenza viruses causing a pandemic outbreak in humans. It is virtually impossible to predict which virus strain will cause the next pandemic and it takes a considerable amount of time before a safe and effective vaccine will be available once a pandemic occurs. In addition, development of pandemic vaccines is hampered by the generally poor immunogenicity of avian influenza viruses in humans. An effective pre-pandemic vaccine is therefore required as a first line of defense. Broadening of the protective efficacy of current seasonal vaccines by adding an adjuvant may be a way to provide such first line of defense. Here we evaluate whether a seasonal trivalent virosomal vaccine (TVV adjuvated with the saponin-based adjuvant Matrix-M (MM can confer protection against avian influenza H5 and H7 virus strains in mice and ferrets. We demonstrate that mice were protected from death against challenges with H5N1 and H7N7, but that the protection was not complete as evidenced by severe clinical signs. In ferrets, protection against H7N9 was not observed. In contrast, reduced upper and lower respiratory tract viral loads and reduced lung pathology, was achieved in H5N1 challenged ferrets. Together these results suggest that, at least to some extent, Matrix-M adjuvated seasonal virosomal influenza vaccine can serve as an interim measure to decrease morbidity and mortality associated with a pandemic outbreak.

  15. Near-infrared laser induced conformational change of alanine in low-temperature matrixes and the tunneling lifetime of its conformer VI.

    Science.gov (United States)

    Bazsó, Gábor; Najbauer, Eszter E; Magyarfalvi, Gábor; Tarczay, György

    2013-03-07

    The near- and mid-IR spectra of α-alanine isolated in low-temperature Ar, Kr, and N2 matrixes were measured. Production of the short-lived conformer VI at the expense of the predominant conformer I was observed upon short irradiation with NIR laser light at the first O-H stretching overtone band of conformer I. Conformer VI decays by H-atom tunneling at 12 K with half-lives of 5.7 ± 1 s, 2.8 ± 1 s in Ar (two different sites), 7.0 ± 1 s in Kr, and 2.8 × 10(3) ± 1.2 × 10(3) s in N2. Upon prolonged irradiation, conformer I slowly transformed into conformer IIa. On the basis of these irradiation experiments, the unambiguous vibrational assignments of conformers I, IIa, and VI are given. In contrast to similar experiments for glycine, the irradiation experiments did not lead to the formation of conformer IIIb. This is explained by a very low IIIb → I barrier height computed for alanine, which results in a very fast depletion of conformer IIIb even in low-temperature matrixes.

  16. [Osteochondritis Dissecans of the Talus with Hindfoot Malalignment--Autologous Matrix-Induced Chondrogenesis with Lateral Calcaneal Distraction Osteotomy in an Internationally Successful Young Female Ski Racer].

    Science.gov (United States)

    Hotfiel, T; Engelhardt, M

    2015-06-01

    Osteochondritis dissecans of the talus (ODT) describes a special entity of osteochondral lesions of the talus (OLT). In the case of an advanced stage or failure of conservative treatment, a wide variety of surgical treatment strategies for osteochondral defects of the ankle have been described. In most cases, the ODT leads to a loss in sports time and competition. In the following case report we describe a case dealing with a young alpine ski racer who competes in international races. An osteochondritis dissecans of the talus was observed and led to pain and loss of sports function. We decided for an operative treatment with an autologous matrix-associated chondrogenesis (AMIC). In addition to the AMIC we performed a lateral calcaneal distraction osteotomy, based on the findings of a flatfoot in order to correct the hindfoot malalignment. At an early time pain relief could be detected. Step by step, the presented ski racer could increase the intensity of training sessions. Based on the findings in the MRI at the follow-up, an integrated repair tissue could be detected. The following case report describes a positive course after an autologous matrix-associated chondrogenesis (AMIC) combined with a lateral calcaneal distraction osteotomy. At this time the athlete is reintegrated in elite sports and takes part in the normal training programmes. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Curcumin inhibits phorbol ester-induced up-regulation of cyclooxygenase-2 and matrix metalloproteinase-9 by blocking ERK1/2 phosphorylation and NF-kappaB transcriptional activity in MCF10A human breast epithelial cells.

    Science.gov (United States)

    Lee, Ki Won; Kim, Jung-Hwan; Lee, Hyong Joo; Surh, Young-Joon

    2005-01-01

    Elevated levels of cyclooxygenase-2 (COX-2) and matrix metalloproteinases (MMPs) are often observed in various types of cancerous and transformed cells, and hence recognized as potential molecular targets for the chemoprevention. In the present study, we investigated the possible inhibitory effects of curcumin on the expression of COX-2 and MMP-9 induced by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA) in MCF10A human breast epithelial (MCF10A) cells and the underlying mechanisms. Curcumin inhibited the TPA-induced COX-2 expression at both transcriptional and post-transcriptional levels, and reduced the synthesis of prostaglandin E(2), one of the major products of COX-2. Likewise, curcumin attenuated invasiveness and motility of MCF10A cells stimulated with TPA through suppression of MMP expression. Curcumin blocked TPA-induced activation of extracellular signal-regulated protein kinase (ERK1/2) and nuclear factor kappaB (NF-kappaB) transcriptional activity. Overexpression of the dominant negative forms of ERK2 abrogated the TPA-induced NF-kappaB transcriptional activity. Treatment of MCF10A cells with U0126, which is a pharmacological inhibitor of ERK1/2, reduced TPA-induced up-regulation of COX-2 and MMP-9. Taken together, these findings suggest that curcumin inhibits the TPA-induced up-regulation of COX-2 and MMP-9 by suppressing ERK1/2 phosphorylation and NF-kappaB trans-activation in human breast epithelial cells, which may contribute to its chemopreventive potential. Antioxid. Redox Signal. 7, 1612-1620.

  18. Uncovering the local inelastic interactions during manufacture of ductile cast iron: How the substructure of the graphite particles can induce residual stress concentrations in the matrix

    DEFF Research Database (Denmark)

    Andriollo, Tito; Hellström, Kristina; Sonne, Mads Rostgaard

    2018-01-01

    Recent X-ray diffraction (XRD) measurements have revealed that plastic deformation and a residual elastic strain field can be present around the graphite particles in ductile cast iron after manufacturing, probably due to some local mismatch in thermal contraction. However, as only one component...... of the elastic strain tensor could be obtained from the XRD data, the shape and magnitude of the associated residual stress field have remained unknown. To compensate for this and to provide theoretical insight into this unexplored topic, a combined experimental-numerical approach is presented in this paper....... First, a ma terial equivalent to the ductile cast iron matrix is manufactured and subjected to dilato- metric and high-temperature tensile tests. Subsequently, a two-scale hierarchical top-down model is devised, calibrated on the basis of the collected data and used to simulate the interaction between...

  19. Tissue inhibitor of matrix metalloproteinase-1 is required for high-fat diet-induced glucose intolerance and hepatic steatosis in mice

    DEFF Research Database (Denmark)

    Fjære, Even; Andersen, Charlotte; Myrmel, Lene Secher

    2015-01-01

    -induced glucose intolerance and hepatic steatosis using the Timp1 null mice. METHODS: Timp1 knockout (TKO) and wild type (TWT) mice were fed chow, high-fat diet (HFD) or intermediate fat and sucrose diet (IFSD). We determined body weight, body composition, lipid content of the liver, energy intake, energy...... and had lower energy efficiency than TWT mice when fed HFD, but not when fed chow or IFSD. Importantly, TKO mice were protected from development of HFD- as well as IFSD-induced glucose intolerance, hepatic steatosis, and altered expression of genes involved in hepatic lipid metabolism and inflammation....... CONCLUSION: Collectively, our results indicate that TIMP-1 contributes to the development of diet-induced hepatic steatosis and glucose intolerance and may be a potential therapeutic target....

  20. Transition Matrix Cluster Algorithms

    OpenAIRE

    Yevick, David; Lee, Yong Hwan

    2018-01-01

    We demonstrate that a series of simple procedures for increasing the efficiency of transition matrix calculations can be realized by integrating the standard single-spin reversal transition matrix method with global cluster inversion techniques.

  1. The Matrix Cookbook

    DEFF Research Database (Denmark)

    Petersen, Kaare Brandt; Pedersen, Michael Syskind

    Matrix identities, relations and approximations. A desktop reference for quick overview of mathematics of matrices.......Matrix identities, relations and approximations. A desktop reference for quick overview of mathematics of matrices....

  2. Specific Caleosin/Peroxygenase and Lipoxygenase Activities Are Tissue-Differentially Expressed in Date Palm (Phoenix dactyliferaL.) Seedlings and Are Further Induced Following Exposure to the Toxin 2,3,7,8-tetrachlorodibenzo-p-dioxin.

    Science.gov (United States)

    Hanano, Abdulsamie; Almousally, Ibrahem; Shaban, Mouhnad; Rahman, Farzana; Hassan, Mehedi; Murphy, Denis J

    2016-01-01

    Two caleosin/peroxygenase isoforms from date palm, Phoenix dactylifera L., PdCLO2 and PdCLO4, were characterized with respect to their tissue expression, subcellular localization, and oxylipin pathway substrate specificities in developing seedlings. Both PdCLO2 and PdCLO4 had peroxygenase activities that peaked at the mid-stage (radicle length of 2.5 cm) of seedling growth and were associated with the lipid droplet (LD) and microsomal fractions. Recombinant PdCLO2 and PdCLO4 proteins heterologously expressed in yeast cells were localized in both LD and microsomal fractions. Each of the purified recombinant proteins exhibited peroxygenase activity but they were catalytically distinct with respect to their specificity and product formation from fatty acid epoxide and hydroxide substrates. We recently showed that date palm CLO genes were upregulated following exposure to the potent toxin, 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) (Hanano et al., 2016), and we show here that transcripts of 9- and 13-lipoxygenase (LOX) genes were also induced by TCDD exposure. At the enzyme level, 9-LOX and 13-LOX activities were present in a range of seedling tissues and responded differently to TCDD exposure, as did the 9- and 13-fatty acid hydroperoxide reductase activities. This demonstrates that at least two branches of the oxylipin pathway are involved in responses to the environmental organic toxin, TCDD in date palm.

  3. Specific Caleosin/Peroxygenase and Lipoxygenase Activities Are Tissue-Differentially Expressed in Date Palm (Phoenix dactylifera L.) Seedlings and Are Further Induced Following Exposure to the Toxin 2,3,7,8-tetrachlorodibenzo-p-dioxin

    Science.gov (United States)

    Hanano, Abdulsamie; Almousally, Ibrahem; Shaban, Mouhnad; Rahman, Farzana; Hassan, Mehedi; Murphy, Denis J.

    2017-01-01

    Two caleosin/peroxygenase isoforms from date palm, Phoenix dactylifera L., PdCLO2 and PdCLO4, were characterized with respect to their tissue expression, subcellular localization, and oxylipin pathway substrate specificities in developing seedlings. Both PdCLO2 and PdCLO4 had peroxygenase activities that peaked at the mid-stage (radicle length of 2.5 cm) of seedling growth and were associated with the lipid droplet (LD) and microsomal fractions. Recombinant PdCLO2 and PdCLO4 proteins heterologously expressed in yeast cells were localized in both LD and microsomal fractions. Each of the purified recombinant proteins exhibited peroxygenase activity but they were catalytically distinct with respect to their specificity and product formation from fatty acid epoxide and hydroxide substrates. We recently showed that date palm CLO genes were upregulated following exposure to the potent toxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (Hanano et al., 2016), and we show here that transcripts of 9- and 13-lipoxygenase (LOX) genes were also induced by TCDD exposure. At the enzyme level, 9-LOX and 13-LOX activities were present in a range of seedling tissues and responded differently to TCDD exposure, as did the 9- and 13-fatty acid hydroperoxide reductase activities. This demonstrates that at least two branches of the oxylipin pathway are involved in responses to the environmental organic toxin, TCDD in date palm. PMID:28111588

  4. Stochastic Matrix Factorization

    OpenAIRE

    Adams, Christopher

    2016-01-01

    This paper considers a restriction to non-negative matrix factorization in which at least one matrix factor is stochastic. That is, the elements of the matrix factors are non-negative and the columns of one matrix factor sum to 1. This restriction includes topic models, a popular method for analyzing unstructured data. It also includes a method for storing and finding pictures. The paper presents necessary and sufficient conditions on the observed data such that the factorization is unique. I...

  5. Matrix with Prescribed Eigenvectors

    Science.gov (United States)

    Ahmad, Faiz

    2011-01-01

    It is a routine matter for undergraduates to find eigenvalues and eigenvectors of a given matrix. But the converse problem of finding a matrix with prescribed eigenvalues and eigenvectors is rarely discussed in elementary texts on linear algebra. This problem is related to the "spectral" decomposition of a matrix and has important technical…

  6. High-dose stabilized chlorite matrix WF10 prolongs cardiac xenograft survival in the hamster-to-rat model without inducing ultrastructural or biochemical signs of cardiotoxicity

    DEFF Research Database (Denmark)

    Hansen, A; Kemp, K; Kemp, E

    2001-01-01

    of high dose WF10 as a single drug regimen in the hamster-to-rat xenotransplantation model and searched for possible cardiotoxic side effects. WF10 prolonged cardiac xenograft survival, but did not induce tolerence or inhibit pathological signs of acute rejection. Hamsters from the donor population...

  7. Involvement of the nuclear progestin receptor in LH-induced expression of membrane type 2-matrix metalloproteinase required for follicle rupture during ovulation in the medaka, Oryzias latipes.

    Science.gov (United States)

    Ogiwara, Katsueki; Takahashi, Takayuki

    2017-07-15

    Hormonal regulation of the expression of Mmp15, a proteolytic enzyme indispensable for ovulation in the teleost medaka, was investigated. In an in vitro culture system using preovulatory follicles, Mmp15 expression and ovulation were induced in the presence of recombinant luteinizing hormone (rLh). Both rLh-induced Mmp15 expression and ovulation were 17α, 20β-dihydroxy-4-pregnen-3-one-dependent, suggesting the involvement of a nuclear progestin receptor (Pgr). In vitro follicle ovulation and Mmp15 expression were reduced by treatment with the Pgr antagonist RU-486. Like Pgr, the transcription factor CCAAT/enhancer-binding protein β (Cebpb) was induced by rLh. ChIP analyses indicated that Pgr and Cebpb bound to the mmp15 promoter region. These results indicate that the rLh-induced expression of Mmp15 is mediated by Pgr and Cebpb. A differential timing of expression of Pgr and Cebpb in the preovulatory follicles appears to explain the considerably long time-lag from the pgr gene activation to mmp15 gene expression. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Basic fibroblast growth factor induces matrix metalloproteinase-13 via ERK MAP kinase-altered phosphorylation and sumoylation of Elk-1 in human adult articular chondrocytes

    Directory of Open Access Journals (Sweden)

    Hee-Jeong Im

    2009-10-01

    Full Text Available Hee-Jeong Im,1–4 Andrew D Sharrocks,5 Xia Lin,6 Dongyao Yan,1 Jaesung Kim,1 Andre J van Wijnen,7 Robert A Hipskind81Departments of Biochemistry, 2Internal Medicine, 3Section of Rheumatology, Orthopedic Surgery, 4Rush University Medical Center, and Department of Bioengineering; University of Illinois at Chicago, IL USA; 5Faculty of Life Sciences, University of Manchester, Oxford Rd, Manchester, UK; 6Michael D DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas, USA; 7Department of Cell Biology, University of Massachusetts Medical School, Worcester, MA, USA; 8Institute De Genetique Moleculaire de Montpellier, FranceAbstract: Degradation of the extracellular matrix (ECM by matrix metalloproteinases (MMPs and release of basic fibroblast growth factor (bFGF are principal aspects of the pathology of osteoarthritis (OA. ECM disruption leads to bFGF release, which activates the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK pathway and its downstream target the Ets-like transcription factor Elk-1. Previously we demonstrated that the bFGF-ERK-Elk-1 signaling axis is responsible for the potent induction of MMP-13 in human primary articular chondrocytes. Here we report that, in addition to phosphorylation of Elk-1, dynamic posttranslational modification of Elk-1 by small ubiquitin-related modifier (SUMO serves as an important mechanism through which MMP-13 gene expression is regulated. We show that bFGF activates Elk-1 mainly through the ERK pathway and that increased phosphorylation of Elk-1 is accompanied by decreased conjugation of SUMO to Elk-1. Reporter gene assays reveal that phosphorylation renders Elk-1 competent for induction of MMP-13 gene transcription, while sumoylation has the opposite effect. Furthermore, we demonstrate that the SUMO-conjugase Ubc9 acts as a key mediator for Elk-1 sumoylation. Taken together, our results suggest that sumoylation antagonizes the phosphorylation

  9. Structure and end-group analysis of complex hexanediol-neopentylglycol-adipic acid copolyesters by matrix-assisted laser desorption/ionization collision-induced dissociation tandem mass spectrometry.

    Science.gov (United States)

    Weidner, Steffen M; Falkenhagen, Jana; Knop, Karin; Thünemann, Andreas

    2009-09-01

    Sequences and end groups of complex copolyesters were determined by fragmentation analysis by means of matrix-assisted laser desorption/ionization collision-induced dissociation tandem mass spectrometry (MALDI CID MS/MS). The complexity of the crude copolyester mixture was reduced by a chromatographic separation followed by a MALDI time-of-flight (TOF) investigation of fractions. Due to overlapping compositional and end-group information a clear assignment of end groups was very difficult. However, the fragmentation of suitable precursor ions resulted in typical fragment ion patterns and, therefore, enabled a fast and unambiguous determination of the end groups and composition of this important class of polymers. Copyright (c) 2009 John Wiley & Sons, Ltd.

  10. NADPH oxidase/ROS-dependent PYK2 activation is involved in TNF-α-induced matrix metalloproteinase-9 expression in rat heart-derived H9c2 cells

    International Nuclear Information System (INIS)

    Yang, Chuen-Mao; Lee, I-Ta; Hsu, Ru-Chun; Chi, Pei-Ling; Hsiao, Li-Der

    2013-01-01

    TNF-α plays a mediator role in the pathogenesis of chronic heart failure contributing to cardiac remodeling and peripheral vascular disturbances. The implication of TNF-α in inflammatory responses has been shown to be mediated through up-regulation of matrix metalloproteinase-9 (MMP-9). However, the detailed mechanisms of TNF-α-induced MMP-9 expression in rat embryonic-heart derived H9c2 cells are largely not defined. We demonstrated that in H9c2 cells, TNF-α induced MMP-9 mRNA and protein expression associated with an increase in the secretion of pro-MMP-9. TNF-α-mediated responses were attenuated by pretreatment with the inhibitor of ROS (N-acetyl-L-cysteine, NAC), NADPH oxidase [apocynin (APO) or diphenyleneiodonium chloride (DPI)], MEK1/2 (U0126), p38 MAPK (SB202190), JNK1/2 (SP600125), NF-κB (Bay11-7082), or PYK2 (PF-431396) and transfection with siRNA of TNFR1, p47 phox , p42, p38, JNK1, p65, or PYK2. Moreover, TNF-α markedly induced NADPH oxidase-derived ROS generation in these cells. TNF-α-enhanced p42/p44 MAPK, p38 MAPK, JNK1/2, and NF-κB (p65) phosphorylation and in vivo binding of p65 to the MMP-9 promoter were inhibited by U0126, SB202190, SP600125, NAC, DPI, or APO. In addition, TNF-α-mediated PYK2 phosphorylation was inhibited by NAC, DPI, or APO. PYK2 inhibition could reduce TNF-α-stimulated MAPKs and NF-κB activation. Thus, in H9c2 cells, we are the first to show that TNF-α-induced MMP-9 expression is mediated through a TNFR1/NADPH oxidase/ROS/PYK2/MAPKs/NF-κB cascade. We demonstrated that NADPH oxidase-derived ROS generation is involved in TNF-α-induced PYK2 activation in these cells. Understanding the regulation of MMP-9 expression and NADPH oxidase activation by TNF-α on H9c2 cells may provide potential therapeutic targets of chronic heart failure. - Highlights: • TNF-α induces MMP-9 secretion and expression via a TNFR1-dependent pathway. • TNF-α induces ROS/PYK2-dependent MMP-9 expression in H9c2 cells. • TNF-α induces

  11. Omentin-1 prevents cartilage matrix destruction by regulating matrix metalloproteinases.

    Science.gov (United States)

    Li, Zhigang; Liu, Baoyi; Zhao, Dewei; Wang, BenJie; Liu, Yupeng; Zhang, Yao; Li, Borui; Tian, Fengde

    2017-08-01

    Matrix metalloproteinases (MMPs) play a crucial role in the degradation of the extracellular matrix and pathological progression of osteoarthritis (OA). Omentin-1 is a newly identified anti-inflammatory adipokine. Little information regarding the protective effects of omentin-1 in OA has been reported before. In the current study, our results indicated that omentin-1 suppressed expression of MMP-1, MMP-3, and MMP-13 induced by the proinflammatory cytokine interleukin-1β (IL-1β) at both the mRNA and protein levels in human chondrocytes. Importantly, administration of omentin-1 abolished IL-1β-induced degradation of type II collagen (Col II) and aggrecan, the two major extracellular matrix components in articular cartilage, in a dose-dependent manner. Mechanistically, omentin-1 ameliorated the expression of interferon regulatory factor 1 (IRF-1) by blocking the JAK-2/STAT3 pathway. Our results indicate that omentin-1 may have a potential chondroprotective therapeutic capacity. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Ablation of EIF5A2 induces tumor vasculature remodeling and improves tumor response to chemotherapy via regulation of matrix metalloproteinase 2 expression.

    Science.gov (United States)

    Wang, Feng-Wei; Cai, Mu-Yan; Mai, Shi-Juan; Chen, Jie-Wei; Bai, Hai-Yan; Li, Yan; Liao, Yi-Ji; Li, Chang-Peng; Tian, Xiao-Peng; Kung, Hsiang-Fu; Guan, Xin-Yuan; Xie, Dan

    2014-08-30

    Hepatocellular carcinoma (HCC) is a highly vascularized tumor with poor clinical outcome. Our previous work has shown that eukaryotic initiation factor 5A2 (EIF5A2) over-expression enhances HCC cell metastasis. In this study, EIF5A2 was identified to be an independent risk factor for poor disease-specific survival among HCC patients. Both in vitro and in vivo assays indicated that ablation of endogenous EIF5A2 inhibited tumor angiogenesis by reducing matrix metalloproteinase 2 (MMP-2) expression. Given that MMP-2 degrades collagen IV, a main component of the vascular basement membrane (BM), we subsequently investigated the effect of EIF5A2 on tumor vasculature remodeling using complementary approaches, including fluorescent immunostaining, transmission electron microscopy, tumor perfusion assays and tumor hypoxia assays. Taken together, our results indicate that EIF5A2 silencing increases tumor vessel wall continuity, increases blood perfusion and improves tumor oxygenation. Additionally, we found that ablation of EIF5A2 enhanced the chemosensitivity of HCC cells to 5-Fluorouracil (5-FU). Finally, we demonstrated that EIF5A2 might exert these functions by enhancing MMP-2 activity via activation of p38 MAPK and JNK/c-Jun pathways. This study highlights an important role of EIF5A2 in HCC tumor vessel remodeling and indicates that EIF5A2 represents a potential therapeutic target in the treatment of HCC.

  13. Fundamental studies of shock-wave-induced degradation of superconductivity in explosively fabricated, bulk, metal-matrix, copper oxide, high-temperature superconductors

    International Nuclear Information System (INIS)

    Niou, Chornyg-Shyr.

    1991-01-01

    Explosive fabrication involves the simultaneous consolidation and encapsulation of superconducting powders within a metal-matrix monolith. However, the residual superconducting properties are found to be degraded as a result of the shock-wave pressure effect. In this study shock pressure varying from 4 GPa to 19 GPa revealed that the degradation of superconductivity increased with increasing peak pressures, and exhibited a steep increase in normal-state resistance (resistance-temperature or R-T curve) and broad superconducting resistance transitions, with decreasing critical temperature. Complete recovery of superconductivity could be achieved for all shock-loaded or explosively fabricated Y-Ba-Cu-O materials above 930 degree C, and above 860 degree C for Bi-Pb-Sr-Ca-Cu-O. Detailed kinetic studies on Y-Ba-Cu-O revealed a two-stage recovery process having different activation energies which were also sensitive to the peak pressure, and therefore to the densities of defects. In the context of the experimental results, a materials engineering strategy was investigated for optimizing the explosive fabrication of superconducting monoliths

  14. Activation of PPARβ/δ protects cardiac myocytes from oxidative stress-induced apoptosis by suppressing generation of reactive oxygen/nitrogen species and expression of matrix metalloproteinases.

    Science.gov (United States)

    Barlaka, Eleftheria; Görbe, Anikó; Gáspár, Renáta; Pálóczi, János; Ferdinandy, Péter; Lazou, Antigone

    2015-01-01

    Heart failure still remains one of the leading causes of morbidity and mortality worldwide. A major contributing factor is reactive oxygen/nitrogen species (RONS) overproduction which is associated with cardiac remodeling partly through cardiomyocyte apoptosis. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that belong to the nuclear receptor superfamily and have been implicated in cardioprotection. However, the molecular mechanisms are largely unexplored. In this study we sought to investigate the potential beneficial effects evoked by activation of PPARβ/δ under the setting of oxidative stress induced by H2O2 in adult rat cardiac myocytes. The selective PPARβ/δ agonist GW0742 inhibited the H2O2-induced apoptosis and increased cell viability. In addition, generation of RONS was attenuated in cardiac myocytes in the presence of PPARβ/δ agonist. These effects were abolished in the presence of the PPARβ/δ antagonist indicating that the effect was through PPARβ/δ receptor activation. Treatment with PPARβ/δ agonist was also associated with attenuation of caspase-3 and PARP cleavage, upregulation of anti-apoptotic Bcl-2 and concomitant downregulation of pro-apoptotic Bax. In addition, activation of PPARβ/δ inhibited the oxidative-stress-induced MMP-2 and MMP-9 mRNA upregulation. It is concluded that PPARβ/δ activation exerts a cytoprotective effect in adult rat cardiac myocytes subjected to oxidative stress via inhibition of oxidative stress, MMP expression, and apoptosis. Our data suggest that the novel connection between PPAR signaling and MMP down-regulation in cardiac myocytes might represent a new target for the management of oxidative stress-induced cardiac dysfunction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Immortalization of human melanocytes does not alter the de novo properties of nitric oxide to induce cell detachment from extracellular matrix components via cGMP.

    Science.gov (United States)

    Ivanova, Krassimira; Lambers, Britta; van den Wijngaard, Rene; Le Poole, I Caroline; Grigorieva, Olga; Gerzer, Rupert; Das, Pranab K

    2008-01-01

    Nitric oxide (NO) is an important mediator in many (patho)physiological processes including inflammation and skin cancer. A key transducer in NO signaling is the soluble guanylyl cyclase (sGC) that catalyzes the formation of guanosine 3',5'-cyclic monophosphate (cGMP). The basic mechanism of NO-cGMP signaling in melanocytic cells is, however, not well elucidated. A setback for such studies is the limited availability of patient-derived melanocytes. Here, we report that immortalized human normal and vitiliginous cell lines generated via cell transfection with human papilloma virus 16 genes E6 and E7 express NO synthase and guanylyl cyclase isoforms and the multidrug resistance-associated proteins 4 and 5 as selective cGMP exporters. Donors of NO (e.g., the NONOate (Z)-1-[N-(3-ammoniopropyl)-N-(n-propyl)amino]diazen-1-ium-1,2-diolate (PAPA-NO) and reactive nitrogen oxygen species (RNOS) like 3-morpholino-sydnonimine (SIN-1) as a donor of peroxynitrite as well as YC-1 as a NO-independent sGC stimulator increased intracellular cGMP levels in immortalized melanocytes (up to eightfold over controls), indicating the expression of functional sGC in these cells. PAPA-NO and SIN-1 also reduced the attachment of immortalized melanocytes to extracellular matrix (ECM) components like fibronectin which was dependent on cellular melanin content and cGMP. Such effects on melanoma cells were positively related to metastatic potential and were cGMP independent. Intriguingly, nonpigmented metastatic melanoma cells were more sensitive to exogenous sources of RNOS than of NO. Thus, immortalized melanocytes can be used as a tool for further research on differences in cell signaling between the different melanocytic lineages in particular towards impairment of cell-ECM adhesion by NO or RNOS, which may be important in metastasis and vitiligo pathogenesis.

  16. Noncommutative spaces from matrix models

    Science.gov (United States)

    Lu, Lei

    Noncommutative (NC) spaces commonly arise as solutions to matrix model equations of motion. They are natural generalizations of the ordinary commutative spacetime. Such spaces may provide insights into physics close to the Planck scale, where quantum gravity becomes relevant. Although there has been much research in the literature, aspects of these NC spaces need further investigation. In this dissertation, we focus on properties of NC spaces in several different contexts. In particular, we study exact NC spaces which result from solutions to matrix model equations of motion. These spaces are associated with finite-dimensional Lie-algebras. More specifically, they are two-dimensional fuzzy spaces that arise from a three-dimensional Yang-Mills type matrix model, four-dimensional tensor-product fuzzy spaces from a tensorial matrix model, and Snyder algebra from a five-dimensional tensorial matrix model. In the first part of this dissertation, we study two-dimensional NC solutions to matrix equations of motion of extended IKKT-type matrix models in three-space-time dimensions. Perturbations around the NC solutions lead to NC field theories living on a two-dimensional space-time. The commutative limit of the solutions are smooth manifolds which can be associated with closed, open and static two-dimensional cosmologies. One particular solution is a Lorentzian fuzzy sphere, which leads to essentially a fuzzy sphere in the Minkowski space-time. In the commutative limit, this solution leads to an induced metric that does not have a fixed signature, and have a non-constant negative scalar curvature, along with singularities at two fixed latitudes. The singularities are absent in the matrix solution which provides a toy model for resolving the singularities of General relativity. We also discussed the two-dimensional fuzzy de Sitter space-time, which has irreducible representations of su(1,1) Lie-algebra in terms of principal, complementary and discrete series. Field

  17. Baicalein, unlike 4-hydroxytamoxifen but similar to G15, suppresses 17β-estradiol-induced cell invasion, and matrix metalloproteinase-9 expression and activation in MCF-7 human breast cancer cells.

    Science.gov (United States)

    Chen, Yan; Hong, Duan-Yang; Wang, Jing; Ling-Hu, Jun; Zhang, Yan-Yan; Pan, Di; Xu, Yi-Ni; Tao, Ling; Luo, Hong; Shen, Xiang-Chun

    2017-08-01

    Estrogen performs an important role in the growth and development of breast cancer. There are at least three major receptors, including estrogen receptor (ER)α and β, and G protein-coupled receptor 30 (GPR30), which mediate the actions of estrogen through using transcriptional and rapid non-genomic signaling pathways. Flavonoids have been considered candidates for chemopreventive agents in breast cancer. Baicalein, the primary flavonoid derived from the root of Scutellaria baicalensis Georgi, has been reported to exert an anti-estrogenic effect. In the present study, the effects of baicalein on 17β-estradiol (E2)-induced cell invasion, and matrix metalloproteinase-9 (MMP-9) expression and activation were investigated. Furthermore, its effects were compared with that of the active form of the ER modulator tamoxifen 4-hydroxytamoxifen (OHT) and the GPR30 antagonist G15 in ERα- and GPR30-positive MCF-7 breast cancer cells. The results demonstrated that OHT failed to prevent E2-induced cell invasion, upregulation and proteolytic activity of MMP-9. However, baicalein was able to significantly suppress these E2-induced effects. Furthermore, E2-stimulated invasion, and MMP-9 expression and activation were significantly attenuated following G15 treatment. In addition, baicalein significantly inhibited G-1, a specific GPR30 agonist, induced invasion, and reduced G-1 promoted expression and activity of MMP-9, consistent with effects of G15. The results of the present study suggest that baicalein is a therapeutic candidate for GPR30-positive breast cancer treatment, and besides ERα targeting the GPR30 receptor it may achieve additional therapeutic benefits in breast cancer.

  18. Parallelism in matrix computations

    CERN Document Server

    Gallopoulos, Efstratios; Sameh, Ahmed H

    2016-01-01

    This book is primarily intended as a research monograph that could also be used in graduate courses for the design of parallel algorithms in matrix computations. It assumes general but not extensive knowledge of numerical linear algebra, parallel architectures, and parallel programming paradigms. The book consists of four parts: (I) Basics; (II) Dense and Special Matrix Computations; (III) Sparse Matrix Computations; and (IV) Matrix functions and characteristics. Part I deals with parallel programming paradigms and fundamental kernels, including reordering schemes for sparse matrices. Part II is devoted to dense matrix computations such as parallel algorithms for solving linear systems, linear least squares, the symmetric algebraic eigenvalue problem, and the singular-value decomposition. It also deals with the development of parallel algorithms for special linear systems such as banded ,Vandermonde ,Toeplitz ,and block Toeplitz systems. Part III addresses sparse matrix computations: (a) the development of pa...

  19. Histologic and histomorphometric evaluation of osteogenesis induced by octacalcium phosphate (OCP combined with bone matrix gelatin (BMG in rat skull defects

    Directory of Open Access Journals (Sweden)

    Sargolzaei F.

    2005-05-01

    Full Text Available Statement of Problem: Several methods are used to enhance bone repair and new bone formation, and bone matrix gelatin (BMG is recently introduced. Purpose: The purpose of this histologic and histomorphometric study was to assess the osteogenic potential and the quantity of new trabecular bone formation after implantation of OCP and BMG alone and in combination into the cranial defects in rat. Materials and Methods: In this experimental study, 100 young male Sprague Dawley rats (5-6 weeks age and 120-150gr weight were divided into four groups randomly. A full thickness standard trephine defect 5mm in diameter was made in the rat’s parietal bone, and 5mg of OCP, BMG alone and in combination were implanted into the defects. No OCP and BMG particles were implanted in control group which was otherwise treated identically. On the 5th, 7th, 14th, 21st and 56th days after implantation, the rats were killed and bone samples collected. After processing the samples by routine histological procedures, 5µm thick sections of bone were cut and stained with Haematoxyline & Eosin (H&E and Alcian Blue and studied histologically and histomorphometrically using light microscope and eyepiece graticule. The amount of newly formed bone was quantitatively measured by the use of histomorphometric methods. Data were analyzed with SAS statistical package using ANOVA and Duncan tests. Results: In the experimental groups, the new bone formation was initiated from the margin of defects during 5-14 days after implantation. During 14-21 days after implantation, bone marrow cavities and bone marrow tissues in newly formed bone were seen. By the end of the study, the newly formed bone increased and was relatively matured and almost all of the implanted materials were absorbed. In control group, at the end of the study, a few clusters of new bone were seen near to the defect margins and host bone. The histomorphometric analysis indicated statistical significant differences in

  20. IL-4 inhibition of IL-1 induced Matrix metalloproteinase-3 (MMP-3) expression in human fibroblasts involves decreased AP-1 activation via negative crosstalk involving of Jun N-terminal kinase (JNK).

    Science.gov (United States)

    Chambers, Mariah; Kirkpatrick, Garrett; Evans, Michel; Gorski, Grzegorz; Foster, Sara; Borghaei, Ruth C

    2013-06-10

    Matrix metalloproteinase-3 (MMP-3) over-expression is associated with tissue destruction in the context of chronic inflammation. Previous studies showed that IL-4 inhibits induction of MMP-3 by IL-1β, and suggested that AP-1 might be involved. Here we show that IL-1 induced binding of transcription factor AP-1 to the MMP-3 promoter consists primarily of c-Jun, JunB, and c-Fos and that binding of c-Jun and c-Fos is inhibited by the combination of cytokines while binding of Jun B is not. Mutation of the AP-1 site in the MMP-3 promoter decreased the ability of IL-4 to inhibit its transcription in transfected MG-63 cells. Western blotting showed that both cytokines activate Jun N-terminal kinase (JNK), but with somewhat different kinetics, and that activation of JNK by both cytokines individually is inhibited by the combination. These results indicate that IL-4 inhibition of MMP-3 expression is associated with reduction of IL-1 induced binding of active forms of the AP-1 dimer, while less active JunB-containing dimers remain, and suggest that these changes are associated with decreased activation of JNK. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Amyloid-beta (25-35) peptide induces the release of pro-matrix metalloprotease 9 (pro-MMP-9) from human neutrophils.

    Science.gov (United States)

    Achilli, Cesare; Ciana, Annarita; Minetti, Giampaolo

    2014-12-01

    Alzheimer's disease (AD) is a degenerative process of the brain, leading to increasing impairment of cognitive functions, and is associated with accumulation in the brain of several amyloid-beta (Aβ) peptides (as amyloid plaques), including Aβ25-35. Neutrophils, the most abundant immune cell type infiltrated in the brain of AD patients, accumulate behind amyloid plaques. Aβ peptides can trigger activation of chemotaxis and oxidative burst in neutrophils, suggesting a role in modulating the neuroinflammation process. We have shown that Aβ25-35 can induce the release from human neutrophils of pro-MMP-9, a metalloprotease involved in the onset of inflammation, corroborating the hypothesis of the involvement of infiltrated neutrophils in the inflammatory processes, which occur in the AD brain.

  2. Aryl hydrocarbon receptor suppresses the osteogenesis of mesenchymal stem cells in collagen-induced arthritic mice through the inhibition of β-catenin

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Yulong [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China); Niu, Menglin [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China); Department of Blood Transfusion, Peking University Cancer Hospital & Institute, No. 52 Fucheng Rd., Beijing 100142 (China); Du, Yuxuan; Mei, Wentong; Cao, Wei; Dou, Yunpeng [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China); Yu, Haitao [Department of Clinical Laboratory, The First Hospital of Lanzhou University, Lanzhou, Gansu Province 730000 (China); Du, Xiaonan [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China); Yuan, Huihui, E-mail: huihui_yuan@163.com [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China); Zhao, Wenming, E-mail: zhao-wenming@163.com [Department of Immunology, School of Basic Medical Sciences, Capital Medical University, No. 10 Xitoutiao, You An Men, Beijing 100069 (China)

    2017-01-15

    The contributions of aryl hydrocarbon receptor (Ahr) to the pathogenesis of rheumatoid arthritis (RA), particularly bone loss, have not been clearly explored. The imbalance between osteoblasts and osteoclasts is a major reason for bone loss. The dysfunction of osteoblasts, which are derived from mesenchymal stem cells (MSCs), induced bone erosion occurs earlier and is characterized as more insidious. Here, we showed that the nuclear expression and translocation of Ahr were both significantly increased in MSCs from collagen-induced arthritis (CIA) mice. The enhanced Ahr suppressed the mRNA levels of osteoblastic markers including Alkaline phosphatase (Alp) and Runt-related transcription factor 2 (Runx2) in the differentiation of MSCs to osteoblasts in CIA. The 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD)-mediated activation of Ahr dose-dependently suppressed the expression of osteoblastic markers. In addition, the expression of β-catenin was reduced in CIA MSCs compared with control, and the TCDD-mediated activation of the Ahr significantly inhibited β-catenin expression. The Wnt3a-induced the activation of Wnt/β-catenin pathway partly rescued the osteogenesis decline induced by TCDD. Taken together, these results indicate that activated Ahr plays a negative role in CIA MSCs osteogenesis, possibly by suppressing the expression of β-catenin. - Highlights: • The Ahr pathway displays an activated profile in CIA MSCs. • The activation of Ahr suppresses osteogenesis in CIA MSCs. • TCDD suppresses osteogenesis in a dose-dependent manner. • The activation of Ahr inhibits β-catenin expression to exacerbate bone erosion.

  3. TNF-α induces matrix metalloproteinase-9-dependent soluble intercellular adhesion molecule-1 release via TRAF2-mediated MAPKs and NF-κB activation in osteoblast-like MC3T3-E1 cells

    Science.gov (United States)

    2014-01-01

    Background Matrix metalloproteinase-9 (MMP-9) has been shown to be induced by cytokines including TNF-α and may contribute to bone inflammatory diseases. However, the mechanisms underlying MMP-9 expression induced by TNF-α in MC3T3-E1 cells remain unclear. Results We applied gelatin zymography, Western blot, RT-PCR, real-time PCR, selective pharmacological inhibitors of transcription (actinomycin D, Act.D), translation (cycloheximide, CHI), c-Src (PP1), MEK1/2 (U0126), p38 MAPK (SB202190), JNK1/2 (SP600125), and NF-κB (Bay11-7082), respective siRNAs transfection, promoter assay, immunofluorescence staining, and ELISA to investigate the MMP-9 expression and soluble ICAM-1 (sICAM-1) release induced by TNF-α in MC3T3-E1 cells. Here we demonstrated that TNF-α-induced MMP-9 expression was attenuated by Act.D, CHI, PP1, U0126, SB202190, SP600125, and Bay11-7082, and by the transfection with siRNAs for ERK2, p38 MAPK, and JNK2. TNF-α-stimulated TNFR1, TRAF2, and c-Src complex formation was revealed by immunoprecipitation and Western blot. Furthermore, TNF-α-stimulated NF-κB phosphorylation and translocation were blocked by Bay11-7082, but not by PP1, U0126, SB202190, or SP600125. TNF-α time-dependently induced MMP-9 promoter activity which was also inhibited by PP1, U0126, SB202190, SP600125, or Bay11-7082. Up-regulation of MMP-9 was associated with the release of sICAM-1 into the cultured medium, which was attenuated by the pretreatment with MMP-2/9i, an MMP-9 inhibitor. Conclusions In this study, we demonstrated that TNF-α up-regulates MMP-9 expression via c-Src, MAPKs, and NF-κB pathways. In addition, TNF-α-induced MMP-9 expression may contribute to the production of sICAM-1 by MC3T3-E1 cells. The interplay between MMP-9 expression and sICAM-1 release may exert an important role in the regulation of bone inflammatory diseases. PMID:24502696

  4. Patience of matrix games

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Ibsen-Jensen, Rasmus; Podolskii, Vladimir V.

    2013-01-01

    For matrix games we study how small nonzero probability must be used in optimal strategies. We show that for image win–lose–draw games (i.e. image matrix games) nonzero probabilities smaller than image are never needed. We also construct an explicit image win–lose game such that the unique optimal...

  5. Unitarity of CKM Matrix

    CERN Document Server

    Saleem, M

    2002-01-01

    The Unitarity of the CKM matrix is examined in the light of the latest available accurate data. The analysis shows that a conclusive result cannot be derived at present. Only more precise data can determine whether the CKM matrix opens new vistas beyond the standard model or not.

  6. Probability matrix decomposition models

    NARCIS (Netherlands)

    Maris, E.; DeBoeck, P.; Mechelen, I. van

    1996-01-01

    In this paper, we consider a class of models for two-way matrices with binary entries of 0 and 1. First, we consider Boolean matrix decomposition, conceptualize it as a latent response model (LRM) and, by making use of this conceptualization, generalize it to a larger class of matrix decomposition

  7. Triangularization of a Matrix

    Indian Academy of Sciences (India)

    ). From this one can see that this equality is als9 true for diagonalizable matrices; just note that eSAs-. 1 = SeAS-I. Finally, the equality car- ries over to all matrices since both sides are continuous functions of a matrix and every matrix is a limit ...

  8. Generation of virus-free induced pluripotent stem cell clones on a synthetic matrix via a single cell subcloning in the naive state.

    Directory of Open Access Journals (Sweden)

    Naoki Nishishita

    Full Text Available CD34+ cord blood cells can be reprogrammed effectively on dishes coated with a synthetic RGD motif polymer (PronectinF® using a temperature sensitive Sendai virus vector (SeV TS7 carrying reprogramming factors OCT3/4, SOX2, KLF4 and c-MYC. Dish-shaped human ES cell-like colonies emerged in serum-free primate ES cell medium (supplemented with bFGF in 20% O2 culture conditions. The copy numbers of SeV TS7 vectors in the cytoplasm were drastically reduced by a temperature shift at 38°C for three days. Then, single cells from colonies were seeded on PronectinF®-coated 96-well plates and cultured under naïve culture conditions (N2B27-based medium supplemented with LIF, forskolin, a MAPK inhibitor, and a GSK inhibitor in 5% O2 for cloning purpose. Dome-shaped mouse ES cell-like colonies from single cells emerged on PronectinF®-coated dishes. These cells were collected and cultured again in primate ES cell medium supplemented with bFGF in 20% O2 and maintained on PronectinF®-coated dishes. Cells were assessed for reprogramming, including the absence of residual SeV and their potential for three germ layer differentiation. Generation of virus-free induced pluripotent stem cell (iPSC clones from single cells under feeder-free conditions will solve some of the safety concerns related to use of xeno- or allogeneic-material in culture, and contribute to the characterization and the standardization of iPS cells intended for use in a clinical setting.

  9. Generation of virus-free induced pluripotent stem cell clones on a synthetic matrix via a single cell subcloning in the naïve state.

    Science.gov (United States)

    Nishishita, Naoki; Shikamura, Masayuki; Takenaka, Chiemi; Takada, Nozomi; Fusaki, Noemi; Fusak, Noemi; Kawamata, Shin

    2012-01-01

    CD34+ cord blood cells can be reprogrammed effectively on dishes coated with a synthetic RGD motif polymer (PronectinF®) using a temperature sensitive Sendai virus vector (SeV TS7) carrying reprogramming factors OCT3/4, SOX2, KLF4 and c-MYC. Dish-shaped human ES cell-like colonies emerged in serum-free primate ES cell medium (supplemented with bFGF) in 20% O2 culture conditions. The copy numbers of SeV TS7 vectors in the cytoplasm were drastically reduced by a temperature shift at 38°C for three days. Then, single cells from colonies were seeded on PronectinF®-coated 96-well plates and cultured under naïve culture conditions (N2B27-based medium supplemented with LIF, forskolin, a MAPK inhibitor, and a GSK inhibitor in 5% O2) for cloning purpose. Dome-shaped mouse ES cell-like colonies from single cells emerged on PronectinF®-coated dishes. These cells were collected and cultured again in primate ES cell medium supplemented with bFGF in 20% O2 and maintained on PronectinF®-coated dishes. Cells were assessed for reprogramming, including the absence of residual SeV and their potential for three germ layer differentiation. Generation of virus-free induced pluripotent stem cell (iPSC) clones from single cells under feeder-free conditions will solve some of the safety concerns related to use of xeno- or allogeneic-material in culture, and contribute to the characterization and the standardization of iPS cells intended for use in a clinical setting.

  10. Quantitative measurement of Au and Fe in ferromagnetic nanoparticles with Laser Induced Breakdown Spectroscopy using a polymer-based gel matrix

    International Nuclear Information System (INIS)

    Borowik, T.; Przybyło, M.; Pala, K.; Otlewski, J.; Langner, M.

    2011-01-01

    The medical applications of nanomaterials require substantial changes in the research and development stage, such as the introduction of new processes and methods, and adequate modifications of the national and international laws on the medical product registration. To accomplish this, proper parameterizations of nano-scaled products need to be developed and implemented, accompanied by suitable measuring methods. The introduction of metallic particles to medical practices requires the precise, quantitative evaluation of the production process and later quantification and characterization of the nanoparticles in biological matrices for the bioavailability and biodistribution evaluation. In order to address these issues we propose a method for the quantitative analysis of the metallic nanoparticles composition by Laser Induced Breakdown Spectroscopy (LIBS). Au/Fe ferro-magnetic nanoparticles were used to evaluate the method applicability. Since the powder form of nanoparticles spatters upon laser ablation, first we had to develop fast, convenient and quantitative method for the nano-powdered sample preparation. The proposed method is based on the polymer gelation of nanopowders or their water suspensions. It has been shown that nanopowders compositional changes throughout the production process, along with their final characterization, can be reliable performed with LIBS technique. The quantitative values obtained were successfully correlated with those derived with ICP technique. - Highlights: ► The atomic composition of nanoparticles was analyzed with LIBS. ► The amount of gold on ferromagnetic particles was quantified by the method. ► Gel fixation was used as new way of handling powdered samples. ► LIBS results are comparable with other equivalent methods (ICP). ► There was a difference between measured and assumed nanoparticle composition.

  11. Fuzzy vulnerability matrix

    International Nuclear Information System (INIS)

    Baron, Jorge H.; Rivera, S.S.

    2000-01-01

    The so-called vulnerability matrix is used in the evaluation part of the probabilistic safety assessment for a nuclear power plant, during the containment event trees calculations. This matrix is established from what is knows as Numerical Categories for Engineering Judgement. This matrix is usually established with numerical values obtained with traditional arithmetic using the set theory. The representation of this matrix with fuzzy numbers is much more adequate, due to the fact that the Numerical Categories for Engineering Judgement are better represented with linguistic variables, such as 'highly probable', 'probable', 'impossible', etc. In the present paper a methodology to obtain a Fuzzy Vulnerability Matrix is presented, starting from the recommendations on the Numerical Categories for Engineering Judgement. (author)

  12. Matrix comparison, Part 2

    DEFF Research Database (Denmark)

    Schneider, Jesper Wiborg; Borlund, Pia

    2007-01-01

    The present two-part article introduces matrix comparison as a formal means for evaluation purposes in informetric studies such as cocitation analysis. In the first part, the motivation behind introducing matrix comparison to informetric studies, as well as two important issues influencing...... such comparisons, matrix generation, and the composition of proximity measures, are introduced and discussed. In this second part, the authors introduce and thoroughly demonstrate two related matrix comparison techniques the Mantel test and Procrustes analysis, respectively. These techniques can compare...... and evaluate the degree of monotonicity between different proximity measures or their ordination results. In common with these techniques is the application of permutation procedures to test hypotheses about matrix resemblances. The choice of technique is related to the validation at hand. In the case...

  13. S-Matrix theory of laser-induced nonsequential double ionization: from electron-electron dynamics to absolute-phase diagnosis

    International Nuclear Information System (INIS)

    Figueira de Morisson Faria, C.; Sanpera, A.; Lewenstein, M.; Schomerus, H.; Liu, X.; Becker, W.

    2005-01-01

    Full text: We provide a summarizing account of a series of investigations, in which laser-induced nonsequential double ionization (NSDI) is described as the inelastic collision of an electron with its parent ion, and treated quantummechanically, within the strong-field approximation. In particular, we employ a specific uniform saddle-point approximation whose only validity requirement is that the saddles occur in pairs. As a first step, we address the question of how the type of the interaction by which the second electron is dislodged, as well as final-state electron-electron repulsion, influences the NDSI differential electron momentum distributions. We found that a contact-type interaction and uncorrelated final electron states yields the best agreement with the experimental results, namely circular-shaped distributions peaked at p 1II = p 2II = ±2 √U p , where p nII (n = 1,2) denotes the electron momentum components parallel to the laser-field polarization and U p the ponderomotive energy. Final-state repulsion leads to a broadening in such distributions, with respect to p 1II = p 2II , whereas a Coulomb-type interaction favors unequal momenta. The influence of the interaction and of final-state electron-electron repulsion is most extreme if at least one of the transverse momentum components is kept small, while, for large transverse momenta, different types of interaction or two-electron final states lead to minor discrepancies. In all cases, we obtain very similar results as compared to a classical ensemble computation, in which electrons are released with a quasi-static tunneling rate, apart from minor differences near the boundary of the momentum region for which the collision process in question is classically allowed. Such results suggest that the residual ion has a strong influence on the dynamics of both electrons in NSDI, screening the long-range interaction and the final-state Coulomb repulsion. This interpretation is strengthened by more recent

  14. The nuclear reaction matrix

    International Nuclear Information System (INIS)

    Krenciglowa, E.M.; Kung, C.L.; Kuo, T.T.S.; Osnes, E.; and Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794)

    1976-01-01

    Different definitions of the reaction matrix G appropriate to the calculation of nuclear structure are reviewed and discussed. Qualitative physical arguments are presented in support of a two-step calculation of the G-matrix for finite nuclei. In the first step the high-energy excitations are included using orthogonalized plane-wave intermediate states, and in the second step the low-energy excitations are added in, using harmonic oscillator intermediate states. Accurate calculations of G-matrix elements for nuclear structure calculations in the Aapprox. =18 region are performed following this procedure and treating the Pauli exclusion operator Q 2 /sub p/ by the method of Tsai and Kuo. The treatment of Q 2 /sub p/, the effect of the intermediate-state spectrum and the energy dependence of the reaction matrix are investigated in detail. The present matrix elements are compared with various matrix elements given in the literature. In particular, close agreement is obtained with the matrix elements calculated by Kuo and Brown using approximate methods

  15. Nuclear reaction matrix

    International Nuclear Information System (INIS)

    Krenciglowa, E.M.; Kung, C.L.; Kuo, T.T.S.; Osnes, E.

    1975-01-01

    Different definitions of the reaction matrix G appropriate to the calculation of nuclear structure are reviewed and discussed. Qualitative physical arguments are presented in support of a two-step calculation of the G-matrix for finite nuclei. In the first step the high-energy excitations are included using orthogonalized plane-wave intermediate states, and in the second step the low-energy excitations are added in, using harmonic oscillator intermediate states. Accurate calculations of G-matrix elements for nuclear structure calculations in the A approximately 18 region are performed following this procedure and treating the Pauli exclusion operator Q/sub 2p/ by the method of Tsai and Kuo. The treatment of Q/sub 2p/, the effect of the intermediate-state spectrum and the energy dependence of the reaction matrix are investigated in detail. The present matrix elements are compared with various matrix elements given in the literature. In particular, close argument is obtained with the matrix elements calculated by Kuo and Brown using approximate methods

  16. Matrix metalloproteinase-9 (MMP9) is involved in the TNF-α-induced fusion of human M13SV1-Cre breast epithelial cells and human MDA-MB-435-pFDR1 cancer cells.

    Science.gov (United States)

    Weiler, Julian; Mohr, Marieke; Zänker, Kurt S; Dittmar, Thomas

    2018-04-10

    In addition to physiological events such as fertilisation, placentation, osteoclastogenesis, or tissue regeneration/wound healing, cell fusion is involved in pathophysiological conditions such as cancer. Cell fusion, which applies to both the proteins and conditions that induce the merging of two or more cells, is not a fully understood process. Inflammation/pro-inflammatory cytokines might be a positive trigger for cell fusion. Using a Cre-LoxP-based cell fusion assay we demonstrated that the fusion between human M13SV1-Cre breast epithelial cells and human MDA-MB-435-pFDR1 cancer cells was induced by the pro-inflammatory cytokine tumour necrosis factor-α (TNF-α). The gene expression profile of the cells in the presence of TNF-α and under normoxic and hypoxic conditions was analysed by cDNA microarray analysis. cDNA microarray data were verified by qPCR, PCR, Western blot and zymography. Quantification of cell fusion events was determined by flow cytometry. Proteins of interest were either blocked or knocked-down using a specific inhibitor, siRNA or a blocking antibody. The data showed an up-regulation of various genes, including claudin-1 (CLDN1), ICAM1, CCL2 and MMP9 in M13SV1-Cre and/or MDA-MB-435-pFDR1 cells. Inhibition of these proteins using a blocking ICAM1 antibody, CLDN1 siRNA or an MMP9 inhibitor showed that only the blockage of MMP9 was correlated with a decreased fusion rate of the cells. Likewise, the tetracycline-based antibiotic minocycline, which exhibits anti-inflammatory properties, was also effective in both inhibiting the TNF-α-induced MMP9 expression in M13SV1-Cre cells and blocking the TNF-α-induced fusion frequency of human M13SV1-Cre breast epithelial cells and human MDA-MB-435-pFDR1 cancer cells. The matrix metalloproteinase-9 (MMP9) is most likely involved in the TNF-α-mediated fusion of human M13SV1-Cre breast epithelial cells and human MDA-MB-435-pFDR1 cancer cells. Likewise, our data indicate that the tetracycline

  17. N-matrix completion problem

    OpenAIRE

    Araújo, C. Mendes; Torregrosa, Juan R.; Urbano, Ana M.

    2003-01-01

    An n x n matrix is called an N-matrix if all principal minors are negative. In this paper, we are interested in N-matrix completion problems, that is, when a partial N-matrix hás an N-matrix completion. In general, a combinatorially or non-combinatorially symmetric partial N-matrix does not have an N-matrix completion. Here we prove that a combinatorially symmetric partial N-matrix has an N-matrix completion if the graph of its specified entries is a 1-chordal graph. We also prove that there ...

  18. Elementary matrix theory

    CERN Document Server

    Eves, Howard

    1980-01-01

    The usefulness of matrix theory as a tool in disciplines ranging from quantum mechanics to psychometrics is widely recognized, and courses in matrix theory are increasingly a standard part of the undergraduate curriculum.This outstanding text offers an unusual introduction to matrix theory at the undergraduate level. Unlike most texts dealing with the topic, which tend to remain on an abstract level, Dr. Eves' book employs a concrete elementary approach, avoiding abstraction until the final chapter. This practical method renders the text especially accessible to students of physics, engineeri

  19. Quantifying matrix product state

    Science.gov (United States)

    Bhatia, Amandeep Singh; Kumar, Ajay

    2018-03-01

    Motivated by the concept of quantum finite-state machines, we have investigated their relation with matrix product state of quantum spin systems. Matrix product states play a crucial role in the context of quantum information processing and are considered as a valuable asset for quantum information and communication purpose. It is an effective way to represent states of entangled systems. In this paper, we have designed quantum finite-state machines of one-dimensional matrix product state representations for quantum spin systems.

  20. The biofilm matrix.

    Science.gov (United States)

    Flemming, Hans-Curt; Wingender, Jost

    2010-09-01

    The microorganisms in biofilms live in a self-produced matrix of hydrated extracellular polymeric substances (EPS) that form their immediate environment. EPS are mainly polysaccharides, proteins, nucleic acids and lipids; they provide the mechanical stability of biofilms, mediate their adhesion to surfaces and form a cohesive, three-dimensional polymer network that interconnects and transiently immobilizes biofilm cells. In addition, the biofilm matrix acts as an external digestive system by keeping extracellular enzymes close to the cells, enabling them to metabolize dissolved, colloidal and solid biopolymers. Here we describe the functions, properties and constituents of the EPS matrix that make biofilms the most successful forms of life on earth.

  1. Severity of Plasma Leakage Is Associated With High Levels of Interferon γ-Inducible Protein 10, Hepatocyte Growth Factor, Matrix Metalloproteinase 2 (MMP-2), and MMP-9 During Dengue Virus Infection.

    Science.gov (United States)

    Her, Zhisheng; Kam, Yiu-Wing; Gan, Victor C; Lee, Bernett; Thein, Tun-Linn; Tan, Jeslin J L; Lee, Linda K; Fink, Katja; Lye, David C; Rénia, Laurent; Leo, Yee-Sin; Ng, Lisa F P

    2017-01-01

     Dengue virus infection typically causes mild dengue fever, but, in severe cases, life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) occur. The pathophysiological hallmark of DHF and DSS is plasma leakage that leads to enhanced vascular permeability, likely due to a cytokine storm.  Ninety patients with dengue during 2010-2012 in Singapore were prospectively recruited and stratified according to their disease phase, primary and secondary infection status, and disease severity, measured by plasma leakage. Clinical parameters were recorded throughout the disease progression. The levels of various immune mediators were quantified using comprehensive multiplex microbead-based immunoassays for 46 immune mediators.  Associations between clinical parameters and immune mediators were analyzed using various statistical methods. Potential immune markers, including interleukin 1 receptor antagonist, interferon γ-inducible protein 10, hepatocyte growth factor, soluble p75 tumor necrosis factor α receptor, vascular cell adhesion molecule 1, and matrix metalloproteinase 2, were significantly associated with significant plasma leakage. Secondary dengue virus infections were also shown to influence disease outcome in terms of disease severity.  This study identified several key markers for exacerbated dengue pathogenesis, notably plasma leakage. This will allow a better understanding of the molecular mechanisms of DHF and DSS in patients with dengue. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  2. Long-lasting humoral immune response induced in HIV-1-infected patients by a synthetic peptide (AT20) derived from the HIV-1 matrix protein p17 functional epitope.

    Science.gov (United States)

    Focà, Emanuele; Iaria, Maria Luisa; Caccuri, Francesca; Fiorentini, Simona; Motta, Davide; Giagulli, Cinzia; Castelli, Francesco; Caruso, Arnaldo

    2015-08-01

    A therapeutic vaccination based on a synthetic peptide (AT20) representative of the HIV-1 matrix protein p17 (p17) functional region, coupled to keyhole limpet hemocyanin (KLH) AT20-KLH was capable of inducing the production of high-avidity antibodies (Abs) toward a previous untargeted p17 hotspot of functional activity in highly active antiretroviral therapy (HAART)-treated HIV-1-infected patients. Since avidity of Abs after immunization and the retention of antigens are important in sustaining the long-lasting production of specific humoral responses, we asked whether AT20-KLH vaccination would result in development of a long-lived immune response. The long-term duration of Ab response to AT20-KLH has been evaluated in 10 patients previously enrolled for the AT20-KLH vaccination trial at day 898 post-immunization. Ab titer and their avidity was assessed using specifically designed ELISA assays, whereas their neutralizing capacity was estimated in vitro using a 'wound sealing assay'. Data obtained show that high titers of specific anti-AT20 Abs were maintained at more than 2 years after the last immunization. Furthermore, these Abs were capable to neutralize exogenous p17, as assessed by ability of sera derived from AT20-KLH-immunized patients to block the ability of p17 to promote cell migration in vitro. This finding attests for a successful AT20-KLH vaccine molecule formulation and for an effective HAART-dependent Ab persistence.

  3. Limit properties of monotone matrix functions

    NARCIS (Netherlands)

    Behrndt, Jussi; Hassi, Seppo; de Snoo, Henk; Wietsma, Rudi

    2012-01-01

    The basic objects in this paper are monotonically nondecreasing n x n matrix functions D(center dot) defined on some open interval l = (a, b) of R and their limit values D(a) and D(b) at the endpoints a and b which are, in general, selfadjoint relations in C-n. Certain space decompositions induced

  4. Tendon functional extracellular matrix.

    Science.gov (United States)

    Screen, Hazel R C; Berk, David E; Kadler, Karl E; Ramirez, Francesco; Young, Marian F

    2015-06-01

    This article is one of a series, summarizing views expressed at the Orthopaedic Research Society New Frontiers in Tendon Research Conference. This particular article reviews the three workshops held under the "Functional Extracellular Matrix" stream. The workshops focused on the roles of the tendon extracellular matrix, such as performing the mechanical functions of tendon, creating the local cell environment, and providing cellular cues. Tendon is a complex network of matrix and cells, and its biological functions are influenced by widely varying extrinsic and intrinsic factors such as age, nutrition, exercise levels, and biomechanics. Consequently, tendon adapts dynamically during development, aging, and injury. The workshop discussions identified research directions associated with understanding cell-matrix interactions to be of prime importance for developing novel strategies to target tendon healing or repair. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  5. Hacking the Matrix.

    Science.gov (United States)

    Czerwinski, Michael; Spence, Jason R

    2017-01-05

    Recently in Nature, Gjorevski et al. (2016) describe a fully defined synthetic hydrogel that mimics the extracellular matrix to support in vitro growth of intestinal stem cells and organoids. The hydrogel allows exquisite control over the chemical and physical in vitro niche and enables identification of regulatory properties of the matrix. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. The Matrix Organization Revisited

    DEFF Research Database (Denmark)

    Gattiker, Urs E.; Ulhøi, John Parm

    1999-01-01

    This paper gives a short overview of matrix structure and technology management. It outlines some of the characteristics and also points out that many organizations may actualy be hybrids (i.e. mix several ways of organizing to allocate resorces effectively).......This paper gives a short overview of matrix structure and technology management. It outlines some of the characteristics and also points out that many organizations may actualy be hybrids (i.e. mix several ways of organizing to allocate resorces effectively)....

  7. High-level inducible Smad4-reexpression in the cervical cancer cell line C4-II is associated with a gene expression profile that predicts a preferential role of Smad4 in extracellular matrix composition

    International Nuclear Information System (INIS)

    Klein-Scory, Susanne; Zapatka, Marc; Eilert-Micus, Christina; Hoppe, Sabine; Schwarz, Elisabeth; Schmiegel, Wolff; Hahn, Stephan A; Schwarte-Waldhoff, Irmgard

    2007-01-01

    Smad4 is a tumour suppressor frequently inactivated in pancreatic and colorectal cancers. We have recently reported loss of Smad4 in every fourth carcinoma of the uterine cervix. Smad4 transmits signals from the TGF-β superfamily of cytokines and functions as a versatile transcriptional co-modulator. The prevailing view suggests that the tumour suppressor function of Smad4 primarily resides in its capability to mediate TGF-β growth inhibitory responses. However, accumulating evidence indicates, that the acquisition of TGF-β resistance and loss of Smad4 may be independent events in the carcinogenic process. Through inducible reexpression of Smad4 in cervical cancer cells we wished to shed more light on this issue and to identify target genes implicated in Smad4 dependent tumor suppression. Smad4-deficient human C4-II cervical carcinoma cells were used to establish inducible Smad4 reexpression using the commercial Tet-on™ system (Clontech). The impact of Smad4 reexpression on cell growth was analysed in vitro and in vivo. Transcriptional responses were assessed through profiling on cDNA macroarrays (Clontech) and validated through Northern blotting. Clones were obtained that express Smad4 at widely varying levels from approximately physiological to 50-fold overexpression. Smad4-mediated tumour suppression in vivo was apparent at physiological expression levels as well as in Smad4 overexpressing clones. Smad4 reexpression in a dose-dependent manner was associated with transcriptional induction of the extracellular matrix-associated genes, BigH3, fibronectin and PAI-1, in response to TGF-β. Smad4-dependent regulation of these secreted Smad4 targets is not restricted to cervical carcinoma cells and was confirmed in pancreatic carcinoma cells reexpressing Smad4 after retroviral transduction and in a stable Smad4 knockdown model. On the other hand, the classical cell cycle-associated TGF-β target genes, c-myc, p21 and p15, remained unaltered. Our results show that

  8. Matrix Information Geometry

    CERN Document Server

    Bhatia, Rajendra

    2013-01-01

    This book is an outcome of the Indo-French Workshop on Matrix Information Geometries (MIG): Applications in Sensor and Cognitive Systems Engineering, which was held in Ecole Polytechnique and Thales Research and Technology Center, Palaiseau, France, in February 23-25, 2011. The workshop was generously funded by the Indo-French Centre for the Promotion of Advanced Research (IFCPAR).  During the event, 22 renowned invited french or indian speakers gave lectures on their areas of expertise within the field of matrix analysis or processing. From these talks, a total of 17 original contribution or state-of-the-art chapters have been assembled in this volume. All articles were thoroughly peer-reviewed and improved, according to the suggestions of the international referees. The 17 contributions presented  are organized in three parts: (1) State-of-the-art surveys & original matrix theory work, (2) Advanced matrix theory for radar processing, and (3) Matrix-based signal processing applications.  

  9. Extracellular matrix, cell skeletons, and embryonic development.

    Science.gov (United States)

    Hay, E D

    1989-09-01

    During embryonic development, the extracellular matrix (ECM) promotes the production of differentiated products by epithelial cells and the migration of mesenchymal cells, and probably also plays a role in epithelial-mesenchymal transformation. Here we examine the role of the cell skeleton (actin, microtubules, intermediate filaments) in mediating matrix effects on mesenchymal cell morphology, migration, and formation. The interaction of both epithelial cells and mesenchymal cells with ECM seems to involve the actin cortex, which is best developed in the base of the epithelial cell, where it attaches to underlying matrix via membrane-intercalated receptors. To interact with the matrix, the fibroblast has appropriate ECM receptors and an actin cortex around the whole cell. The actin cortex is absolutely required for assumption of bipolar shape, elongation, and movement through the matrix. Since the cortex seems to be anchored to the matrix, it is unlikely that it moves during cell migration. A new hypothesis states that the microtubule- and intermediate filament-rich endoplasm, containing the nucleus, moves past the actin cortex-receptor-matrix complex into the newly synthesized front end of the mesenchymal cell to effect forward movement. When epithelial cells transform into mesenchyme in the embryo, or when they are induced to do this in vitro, they switch from the keratin intermediate filament profile to one rich in vimentin, and the effect of cell matrix interaction on cell shape is profoundly altered. Vimentin-actin interactions with ECM may be a major factor in the ability of a cell to become mesenchymal.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Fast methods for resumming matrix polynomials and Chebyshev matrix polynomials

    International Nuclear Information System (INIS)

    Liang Wanzen; Baer, Roi; Saravanan, Chandra; Shao Yihan; Bell, Alexis T.; Head-Gordon, Martin

    2004-01-01

    Fast and effective algorithms are discussed for resumming matrix polynomials and Chebyshev matrix polynomials. These algorithms lead to a significant speed-up in computer time by reducing the number of matrix multiplications required to roughly twice the square root of the degree of the polynomial. A few numerical tests are presented, showing that evaluation of matrix functions via polynomial expansions can be preferable when the matrix is sparse and these fast resummation algorithms are employed

  11. Downregulation of reversion-inducing cysteine-rich protein with Kazal motifs in malignant melanoma: inverse correlation with membrane-type 1-matrix metalloproteinase and tissue inhibitor of metalloproteinase 2.

    Science.gov (United States)

    Jacomasso, Thiago; Trombetta-Lima, Marina; Sogayar, Mari C; Winnischofer, Sheila M B

    2014-02-01

    The invasive phenotype of many tumors is associated with an imbalance between the matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs), and the membrane-anchored reversion-inducing cysteine-rich protein with Kazal motifs (RECK). RECK inhibits MMP-2, MMP-9, and MT1-MMP, and has been linked to patient survival and better prognosis in several types of tumors. However, despite the wide implication of these MMPs in melanoma establishment and progression, the role of RECK in this type of tumor is still unknown. Here, we analyzed the expression of RECK, TIMP1, TIMP2, TIMP3, MT1MMP, MMP2, and MMP9 in two publicly available melanoma microarray datasets and in a panel of human melanoma cell lines. We found that RECK is downregulated in malignant melanoma, accompanied by upregulation of MT1MMP and TIMP2. In both datasets, we observed that the group of samples displaying higher RECK levels show lower median expression levels of MT1MMP and TIMP2 and higher levels of TIMP3. When tested in a sample-wise manner, these correlations were statistically significant. Inverse correlations between RECK, MT1MMP, and TIMP2 were verified in a panel of human melanoma cell lines and in a further reduced model that includes a pair of matched primary tumor-derived and metastasis-derived cell lines. Taken together, our data indicate a consistent correlation between RECK, MT1MMP, and TIMP2 across different models of clinical samples and cell lines and suggest evidence of the potential use of this subset of genes as a gene signature for diagnosing melanoma.

  12. Observation of Fermi Arc Surface States Induced by Organic Memristive/Memcapacitive Devices with a Double-Helical Polarized Single-Wall Nanotube Membrane for Direct Chelating with Matrix Matelloproteinase-2

    Directory of Open Access Journals (Sweden)

    E. T. CHEN

    2017-07-01

    Full Text Available Matrix Matelloproteinase-2 (MMP-2 plays a key role in many diseases. A new type of dual-functioning device was developed for fast, direct ultrasensitive detection of MMP-2. We report a memristive/memcapacitive device with vertex double-helical polarized biomimetic protein nanotubules forming double membranes with potential gradient mimicking mitochondria’s inner double membrane has developed. We also report Fermi arcs with nodes on the surface of the nanostructured membrane was observed at the first time by using a 3D real-time - energy-current dynamic mapping method based on data obtained from the Cyclic Voltammetry (CV method. The memristive/memcapacitive device comprises a cross- linked organic polymer having single-wall cross-bar polarized nanotube self-assembling membrane (SAM on a gold chip, under an applied potential, a pair of vertex double- helical circular current flow induced the Fermi arcs states occurrence and these Fermi arcs promoted a direct chelating with zinc ions of the MMP-2 to become possible without any antibody, tracer, or reagent used at room temperature was accomplished. We observed the pair of Dirac Cones became alignment and strengthened with each other in the presence of MMP-2 compared without MMP-2. The MMP-2 can be detected with ag/mL level sensitivity and the value of Detection of Limits (DOL reached orders of magnitude lower than published reports with simplified procedures by a Chronoamperometry (CA method and a Double Step Chronopotentiometry (DSCPO method using NIST SRM 965A standard human serum, respectively. The results show a feasible application for developing the commercial fast and real-time MMP monitoring devices for various diseases.

  13. 2016 MATRIX annals

    CERN Document Server

    Praeger, Cheryl; Tao, Terence

    2018-01-01

    MATRIX is Australia’s international, residential mathematical research institute. It facilitates new collaborations and mathematical advances through intensive residential research programs, each lasting 1-4 weeks. This book is a scientific record of the five programs held at MATRIX in its first year, 2016: Higher Structures in Geometry and Physics (Chapters 1-5 and 18-21); Winter of Disconnectedness (Chapter 6 and 22-26); Approximation and Optimisation (Chapters 7-8); Refining C*-Algebraic Invariants for Dynamics using KK-theory (Chapters 9-13); Interactions between Topological Recursion, Modularity, Quantum Invariants and Low-dimensional Topology (Chapters 14-17 and 27). The MATRIX Scientific Committee selected these programs based on their scientific excellence and the participation rate of high-profile international participants. Each program included ample unstructured time to encourage collaborative research; some of the longer programs also included an embedded conference or lecture series. The artic...

  14. Matrix interdiction problem

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Feng [Los Alamos National Laboratory; Kasiviswanathan, Shiva [Los Alamos National Laboratory

    2010-01-01

    In the matrix interdiction problem, a real-valued matrix and an integer k is given. The objective is to remove k columns such that the sum over all rows of the maximum entry in each row is minimized. This combinatorial problem is closely related to bipartite network interdiction problem which can be applied to prioritize the border checkpoints in order to minimize the probability that an adversary can successfully cross the border. After introducing the matrix interdiction problem, we will prove the problem is NP-hard, and even NP-hard to approximate with an additive n{gamma} factor for a fixed constant {gamma}. We also present an algorithm for this problem that achieves a factor of (n-k) mUltiplicative approximation ratio.

  15. Dynamic Matrix Rank

    DEFF Research Database (Denmark)

    Frandsen, Gudmund Skovbjerg; Frandsen, Peter Frands

    2009-01-01

    We consider maintaining information about the rank of a matrix under changes of the entries. For n×n matrices, we show an upper bound of O(n1.575) arithmetic operations and a lower bound of Ω(n) arithmetic operations per element change. The upper bound is valid when changing up to O(n0.575) entries...... in a single column of the matrix. We also give an algorithm that maintains the rank using O(n2) arithmetic operations per rank one update. These bounds appear to be the first nontrivial bounds for the problem. The upper bounds are valid for arbitrary fields, whereas the lower bound is valid for algebraically...... closed fields. The upper bound for element updates uses fast rectangular matrix multiplication, and the lower bound involves further development of an earlier technique for proving lower bounds for dynamic computation of rational functions....

  16. MiR-143-3p controls TGF-β1-induced cell proliferation and extracellular matrix production in airway smooth muscle via negative regulation of the nuclear factor of activated T cells 1.

    Science.gov (United States)

    Cheng, Wei; Yan, Kun; Xie, Li-Yi; Chen, Feng; Yu, Hong-Chuan; Huang, Yan-Xia; Dang, Cheng-Xue

    2016-10-01

    MicroRNAs (miRNAs) are small noncoding RNAs that function in diverse biological processes. However, little is known about the precise role of microRNAs in the functioning of airway smooth muscle cells (ASMCs). Here, we investigated the potential role and mechanisms of the miR-143 -3p on proliferation and the extracellular matrix (ECM) protein production of ASMCs. We demonstrated that miR-143-3p was aberrantly lower in ASMCs isolated from individuals with asthma than in individuals without asthma. Meanwhile, TGF-β1 caused a marked decrease in a time-dependent manner in miR-143-3p expression in ASMCs from asthmatics. Additionally, the overexpression of miR- 143-3p robustly reduced TGF-β1-induced ASMCs proliferation and downregulated CDK and cyclin expression, whereas the inhibition of miR-143-3p significantly enhanced ASMCs proliferation and upregulated the level of CDKs and cyclins. Re-expression of miR-143-3p attenuated ECM protein deposition reflected as a marked decrease in the expression of type I collagen and fibronectin, whereas miR-143-3p downregulation caused an opposite effect on the expression of type I collagen and fibronectin. Moreover, qRT-PCR and western blot analysis indicated that miR-143-3p negatively regulated the expression of nuclear factor of activated T cells 1 (NFATc1). Subsequent analyses demonstrated that NFATc1 was a direct and functional target of miR-143-3p, which was validated by the dual luciferase reporter assay. Most importantly, the overexpression of NFATc1 effectively reversed the inhibition of miR-143-3p on TGF-β1-induced proliferation, and strikingly abrogated the effect of miR-143-3p on the expression of CDK4 and Cyclin D1. Together, miR-143-3p may function as an inhibitor of asthma airway remodeling by suppressing proliferation and ECM protein deposition in TGF-β1-mediated ASMCs via the negative regulation of NFATc1 signaling, suggesting miR-143-3p as a potential therapeutic target for asthma. Copyright © 2016 Elsevier Ltd

  17. Elementary matrix algebra

    CERN Document Server

    Hohn, Franz E

    2012-01-01

    This complete and coherent exposition, complemented by numerous illustrative examples, offers readers a text that can teach by itself. Fully rigorous in its treatment, it offers a mathematically sound sequencing of topics. The work starts with the most basic laws of matrix algebra and progresses to the sweep-out process for obtaining the complete solution of any given system of linear equations - homogeneous or nonhomogeneous - and the role of matrix algebra in the presentation of useful geometric ideas, techniques, and terminology.Other subjects include the complete treatment of the structur

  18. Complex matrix model duality

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T.W.

    2010-11-15

    The same complex matrix model calculates both tachyon scattering for the c=1 non-critical string at the self-dual radius and certain correlation functions of half-BPS operators in N=4 super- Yang-Mills. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich- Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces. (orig.)

  19. R-matrix methods

    International Nuclear Information System (INIS)

    Robb, W.D.

    1978-01-01

    The procedures used in the application of R-matrix theory to atomic and molecular collision processes are presented. The computationally advantageous features of these methods are high-lighted, and some applications to electron scattering and photoionization are briefly discussed

  20. A Matrix Isolation Infrared

    Indian Academy of Sciences (India)

    The elusive ≡C-H· · ·O complex in the hydrogen bonded systems of Phenylacetylene: A Matrix Isolation Infrared and Ab Initio Study ... A comparison of the spectral shifts observed in the features of PhAc-MeOH and PhAc-DEE would therefore independently confirm the existence or not of n-σ* complex in both these systems.

  1. Challenging the CSCW matrix

    DEFF Research Database (Denmark)

    Jørnø, Rasmus Leth Vergmann; Gynther, Karsten; Christensen, Ove

    2014-01-01

    useful information, we question whether the axis of time and space comprising the matrix pertains to relevant defining properties of the tools, technology or learning environments to which they are applied. Subsequently we offer an example of an Adobe Connect e-learning session as an illustration...

  2. R-matrix analysis

    International Nuclear Information System (INIS)

    Dodder, D.C.

    1975-01-01

    Scattering and reaction processes involving very few nucleons are studied via the R matrix formalism of Wigner and Eisenbud. As examples, the d + 3 He, p + 4 He, 3 He + 4 He, and p + 6 Li are considered. (3 figures) (SDF)

  3. Combinatorial matrix theory

    CERN Document Server

    Mitjana, Margarida

    2018-01-01

    This book contains the notes of the lectures delivered at an Advanced Course on Combinatorial Matrix Theory held at Centre de Recerca Matemàtica (CRM) in Barcelona. These notes correspond to five series of lectures. The first series is dedicated to the study of several matrix classes defined combinatorially, and was delivered by Richard A. Brualdi. The second one, given by Pauline van den Driessche, is concerned with the study of spectral properties of matrices with a given sign pattern. Dragan Stevanović delivered the third one, devoted to describing the spectral radius of a graph as a tool to provide bounds of parameters related with properties of a graph. The fourth lecture was delivered by Stephen Kirkland and is dedicated to the applications of the Group Inverse of the Laplacian matrix. The last one, given by Ángeles Carmona, focuses on boundary value problems on finite networks with special in-depth on the M-matrix inverse problem.

  4. Matrix correction for PIXE in biomedical samples

    International Nuclear Information System (INIS)

    Heck, D.; Rokita, E.

    1985-03-01

    This report describes the programs MATRIX2, STPPWRF2 and MUROFIT, which are used for the calculation of the matrix correction factors, which must be applied to concentrations determined by PIXE (Proton induced X-ray emission). The correction takes into account the slowing down of the protons along their path through the specimen, which causes a decreasing X-ray production along this path. Moreover these X-rays are attenuated penetrating the specimen towards to the X-ray detector. The matrix correction factors regard these effects in dependence on the proton impact energy, the specimen and detector geometry, the specimen composition and the energies of the interesting X-rays. (orig.) [de

  5. Sparse matrix decompositions for clustering

    OpenAIRE

    Blumensath, Thomas

    2014-01-01

    Clustering can be understood as a matrix decomposition problem, where a feature vector matrix is represented as a product of two matrices, a matrix of cluster centres and a matrix with sparse columns, where each column assigns individual features to one of the cluster centres. This matrix factorisation is the basis of classical clustering methods, such as those based on non-negative matrix factorisation but can also be derived for other methods, such as k-means clustering. In this paper we de...

  6. Paths correlation matrix.

    Science.gov (United States)

    Qian, Weixian; Zhou, Xiaojun; Lu, Yingcheng; Xu, Jiang

    2015-09-15

    Both the Jones and Mueller matrices encounter difficulties when physically modeling mixed materials or rough surfaces due to the complexity of light-matter interactions. To address these issues, we derived a matrix called the paths correlation matrix (PCM), which is a probabilistic mixture of Jones matrices of every light propagation path. Because PCM is related to actual light propagation paths, it is well suited for physical modeling. Experiments were performed, and the reflection PCM of a mixture of polypropylene and graphite was measured. The PCM of the mixed sample was accurately decomposed into pure polypropylene's single reflection, pure graphite's single reflection, and depolarization caused by multiple reflections, which is consistent with the theoretical derivation. Reflection parameters of rough surface can be calculated from PCM decomposition, and the results fit well with the theoretical calculations provided by the Fresnel equations. These theoretical and experimental analyses verify that PCM is an efficient way to physically model light-matter interactions.

  7. Partially separable t matrix

    International Nuclear Information System (INIS)

    Sasakawa, T.; Okuno, H.; Ishikawa, S.; Sawada, T.

    1982-01-01

    The off-shell t matrix is expressed as a sum of one nonseparable and one separable terms so that it is useful for applications to more-than-two body problems. All poles are involved in this one separable term. Both the nonseparable and the separable terms of the kernel G 0 t are regular at the origin. The nonseparable term of this kernel vanishes at large distances, while the separable term behaves asymptotically as the spherical Hankel function. These properties make our expression free from defects inherent in the Jost or the K-matrix expressions, and many applications are anticipated. As the application, a compact expression of the many-level formula is presented. Also the application is suggested to the breakup threebody problem based on the Faddeev equation. It is demonstrated that the breakup amplitude is expressed in a simple and physically interesting form and we can calculate it in coordinate space

  8. A matrix contraction process

    Science.gov (United States)

    Wilkinson, Michael; Grant, John

    2018-03-01

    We consider a stochastic process in which independent identically distributed random matrices are multiplied and where the Lyapunov exponent of the product is positive. We continue multiplying the random matrices as long as the norm, ɛ, of the product is less than unity. If the norm is greater than unity we reset the matrix to a multiple of the identity and then continue the multiplication. We address the problem of determining the probability density function of the norm, \

  9. Holomorphic matrix integrals

    International Nuclear Information System (INIS)

    Felder, Giovanni; Riser, Roman

    2004-01-01

    We study a class of holomorphic matrix models. The integrals are taken over middle-dimensional cycles in the space of complex square matrices. As the size of the matrices tends to infinity, the distribution of eigenvalues is given by a measure with support on a collection of arcs in the complex planes. We show that the arcs are level sets of the imaginary part of a hyperelliptic integral connecting branch points

  10. Matrix groups for undergraduates

    CERN Document Server

    Tapp, Kristopher

    2016-01-01

    Matrix groups touch an enormous spectrum of the mathematical arena. This textbook brings them into the undergraduate curriculum. It makes an excellent one-semester course for students familiar with linear and abstract algebra and prepares them for a graduate course on Lie groups. Matrix Groups for Undergraduates is concrete and example-driven, with geometric motivation and rigorous proofs. The story begins and ends with the rotations of a globe. In between, the author combines rigor and intuition to describe the basic objects of Lie theory: Lie algebras, matrix exponentiation, Lie brackets, maximal tori, homogeneous spaces, and roots. This second edition includes two new chapters that allow for an easier transition to the general theory of Lie groups. From reviews of the First Edition: This book could be used as an excellent textbook for a one semester course at university and it will prepare students for a graduate course on Lie groups, Lie algebras, etc. … The book combines an intuitive style of writing w...

  11. Extracellular matrix structure.

    Science.gov (United States)

    Theocharis, Achilleas D; Skandalis, Spyros S; Gialeli, Chrysostomi; Karamanos, Nikos K

    2016-02-01

    Extracellular matrix (ECM) is a non-cellular three-dimensional macromolecular network composed of collagens, proteoglycans/glycosaminoglycans, elastin, fibronectin, laminins, and several other glycoproteins. Matrix components bind each other as well as cell adhesion receptors forming a complex network into which cells reside in all tissues and organs. Cell surface receptors transduce signals into cells from ECM, which regulate diverse cellular functions, such as survival, growth, migration, and differentiation, and are vital for maintaining normal homeostasis. ECM is a highly dynamic structural network that continuously undergoes remodeling mediated by several matrix-degrading enzymes during normal and pathological conditions. Deregulation of ECM composition and structure is associated with the development and progression of several pathologic conditions. This article emphasizes in the complex ECM structure as to provide a better understanding of its dynamic structural and functional multipotency. Where relevant, the implication of the various families of ECM macromolecules in health and disease is also presented. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Avaliação das metaloproteinases de matriz -2 e -9 em gatos com desmineralização óssea secundária à tirotoxicose induzida Evaluation of matrix metalloproteinases -2 and -9 in cats under bone demineralization secondary to induced thyrotoxicosis

    Directory of Open Access Journals (Sweden)

    F.S. Costa

    2008-10-01

    Full Text Available Observou-se significativo aumento de atividade das formas ativas das metaloproteinases -2 e -9 em gatos com tirotoxicose induzida e desmineralização óssea. As formas pró e intermediária da metaloproteinase -2 elevaram-se com 14 dias de administração hormonal, porém, posteriormente, houve uma tendência de queda. Observou-se correlação negativa entre a forma ativa das metaloproteinases de matriz -2 e -9 e a densidade mineral óssea da extremidade distal do rádio. Os resultados sugerem aumento da degradação da matriz colágena secundária com a elevação dos hormônios tiroidianos.Significant increase of activity of active forms of matrix metalloproteinases -2 and -9 in cats under induced thyrotoxicosis and bone demineralization was observed. Pro and intermediated forms of matrix metalloproteinases -2 and -9 increased at 14 days of hormonal treatment, followed by decrease tendency. A negative correlation between active forms of matrix metalloproteinases -2 and -9 and bone mineral density of radius distal extremity was also observed. The results suggest an increase of collagen matrix degradation secondary to high levels of thyroid hormones.

  13. Standard Errors for Matrix Correlations.

    Science.gov (United States)

    Ogasawara, Haruhiko

    1999-01-01

    Derives the asymptotic standard errors and intercorrelations for several matrix correlations assuming multivariate normality for manifest variables and derives the asymptotic standard errors of the matrix correlations for two factor-loading matrices. (SLD)

  14. The cellulose resource matrix.

    Science.gov (United States)

    Keijsers, Edwin R P; Yılmaz, Gülden; van Dam, Jan E G

    2013-03-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where large scale competition can be expected and already is observed for the traditional industries such as the paper industry. Cellulose and lignocellulosic raw materials (like wood and non-wood fibre crops) are being utilised in many industrial sectors. Due to the initiated transition towards biobased economy, these raw materials are intensively investigated also for new applications such as 2nd generation biofuels and 'green' chemicals and materials production (Clark, 2007; Lange, 2007; Petrus & Noordermeer, 2006; Ragauskas et al., 2006; Regalbuto, 2009). As lignocellulosic raw materials are available in variable quantities and qualities, unnecessary competition can be avoided via the choice of suitable raw materials for a target application. For example, utilisation of cellulose as carbohydrate source for ethanol production (Kabir Kazi et al., 2010) avoids the discussed competition with easier digestible carbohydrates (sugars, starch) deprived from the food supply chain. Also for cellulose use as a biopolymer several different competing markets can be distinguished. It is clear that these applications and markets will be influenced by large volume shifts. The world will have to reckon with the increase of competition and feedstock shortage (land use/biodiversity) (van Dam, de Klerk-Engels, Struik, & Rabbinge, 2005). It is of interest - in the context of sustainable development of the bioeconomy - to categorize the already available and emerging lignocellulosic resources in a matrix structure. When composing such "cellulose resource matrix" attention should be given to the quality aspects as well as to the available quantities and practical possibilities of processing the

  15. Bioengineering Human Myocardium on Native Extracellular Matrix

    Science.gov (United States)

    Guyette, Jacques P.; Charest, Jonathan M; Mills, Robert W; Jank, Bernhard J.; Moser, Philipp T.; Gilpin, Sarah E.; Gershlak, Joshua R.; Okamoto, Tatsuya; Gonzalez, Gabriel; Milan, David J.; Gaudette, Glenn R.; Ott, Harald C.

    2015-01-01

    Rationale More than 25 million individuals suffer from heart failure worldwide, with nearly 4,000 patients currently awaiting heart transplantation in the United States. Donor organ shortage and allograft rejection remain major limitations with only about 2,500 hearts transplanted each year. As a theoretical alternative to allotransplantation, patient-derived bioartificial myocardium could provide functional support and ultimately impact the treatment of heart failure. Objective The objective of this study is to translate previous work to human scale and clinically relevant cells, for the bioengineering of functional myocardial tissue based on the combination of human cardiac matrix and human iPS-derived cardiac myocytes. Methods and Results To provide a clinically relevant tissue scaffold, we translated perfusion-decellularization to human scale and obtained biocompatible human acellular cardiac scaffolds with preserved extracellular matrix composition, architecture, and perfusable coronary vasculature. We then repopulated this native human cardiac matrix with cardiac myocytes derived from non-transgenic human induced pluripotent stem cells (iPSCs) and generated tissues of increasing three-dimensional complexity. We maintained such cardiac tissue constructs in culture for 120 days to demonstrate definitive sarcomeric structure, cell and matrix deformation, contractile force, and electrical conduction. To show that functional myocardial tissue of human scale can be built on this platform, we then partially recellularized human whole heart scaffolds with human iPSC-derived cardiac myocytes. Under biomimetic culture, the seeded constructs developed force-generating human myocardial tissue, showed electrical conductivity, left ventricular pressure development, and metabolic function. Conclusions Native cardiac extracellular matrix scaffolds maintain matrix components and structure to support the seeding and engraftment of human iPS-derived cardiac myocytes, and enable