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Sample records for requires mesenchymal contact

  1. Epithelial growth by rat vibrissae follicles in vitro requires mesenchymal contact via native extracellular matrix

    International Nuclear Information System (INIS)

    Link, R.E.; Paus, R.; Stenn, K.S.; Kuklinska, E.; Moellmann, G.

    1990-01-01

    An in vitro assay utilizing the rat vibrissa anagen follicle as a model for studying the epithelial-mesenchymal interactions (EMI) in hair growth is described. Through selective disruption of the epithelial-mesenchymal interface, we investigate whether the specialized extracellular matrix (ECM) of the dermal papilla and basement membrane zone (BMZ) serves a crucial function in hair follicle EMI. Epithelial bulbs incubated intact within their follicular sheaths incorporate thymidine primarily into cells of the hair matrix and outer root sheath, as shown by autoradiography. However, after removal of its mesenchymal associations (dermal papilla and extrabulbar connective tissue), the epithelial bulb showed no incorporation. Neither externally added collagen (type I or IV) nor the basement membrane components in Matrigel could substitute for the growth supporting influence of native surrounding stroma. Mechanical separation of the bulb from the dermal papilla in the basement membrane zone inhibited thymidine incorporation by the epithelium even though mesenchyme was still in close proximity. Enzymatic digestion of the dermal papilla ECM and the basal lamina by Dispase, a fibronectinase and type IV collagenase, also inhibited bulb growth without evidence of cytotoxicity. These experiments suggest that direct epithelial to mesenchymal contact is required for the support of follicular epithelial growth in vitro and that specific ECM components, possibly fibronectin and/or type IV collagen, rather than diffusable factors alone, play a crucial role in the mechanism of hair follicle EMI. The in vitro system described here provides an alternative to developmental EMI models and may serve as a valuable tool for studying EMI in the adult mammalian organism

  2. Mesenchymal Stem Cells Induce Epithelial to Mesenchymal Transition in Colon Cancer Cells through Direct Cell-to-Cell Contact

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    Hidehiko Takigawa

    2017-05-01

    Full Text Available We previously reported that in an orthotopic nude mouse model of human colon cancer, bone marrow–derived mesenchymal stem cells (MSCs migrated to the tumor stroma and promoted tumor growth and metastasis. Here, we evaluated the proliferation and migration ability of cancer cells cocultured with MSCs to elucidate the mechanism of interaction between cancer cells and MSCs. Proliferation and migration of cancer cells increased following direct coculture with MSCs but not following indirect coculture. Thus, we hypothesized that direct contact between cancer cells and MSCs was important. We performed a microarray analysis of gene expression in KM12SM colon cancer cells directly cocultured with MSCs. Expression of epithelial-mesenchymal transition (EMT–related genes such as fibronectin (FN, SPARC, and galectin 1 was increased by direct coculture with MSCs. We also confirmed the upregulation of these genes with real-time polymerase chain reaction. Gene expression was not elevated in cancer cells indirectly cocultured with MSCs. Among the EMT-related genes upregulated by direct coculture with MSCs, we examined the immune localization of FN, a well-known EMT marker. In coculture assay in chamber slides, expression of FN was seen only at the edges of cancer clusters where cancer cells directly contacted MSCs. FN expression in cancer cells increased at the tumor periphery and invasive edge in orthotopic nude mouse tumors and human colon cancer tissues. These results suggest that MSCs induce EMT in colon cancer cells via direct cell-to-cell contact and may play an important role in colon cancer metastasis.

  3. Sliding contact loading enhances the tensile properties of mesenchymal stem cell-seeded hydrogels

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    AH Huang

    2012-07-01

    Full Text Available The primary goal of cartilage tissue engineering is to recapitulate the functional properties and structural features of native articular cartilage. While there has been some success in generating near-native compressive properties, the tensile properties of cell-seeded constructs remain poor, and key features of cartilage, including inhomogeneity and anisotropy, are generally absent in these engineered constructs. Therefore, in an attempt to instill these hallmark properties of cartilage in engineered cell-seeded constructs, we designed and characterized a novel sliding contact bioreactor to recapitulate the mechanical stimuli arising from physiologic joint loading (two contacting cartilage layers. Finite element modeling of this bioreactor system showed that tensile strains were direction-dependent, while both tensile strains and fluid motion were depth-dependent and highest in the region closest to the contact surface. Short-term sliding contact of mesenchymal stem cell (MSC-seeded agarose improved chondrogenic gene expression in a manner dependent on both the axial strain applied and transforming growth factor-β supplementation. Using the optimized loading parameters derived from these short-term studies, long-term sliding contact was applied to MSC-seeded agarose constructs for 21 d. After 21 d, sliding contact significantly improved the tensile properties of MSC-seeded constructs and elicited alterations in type II collagen and proteoglycan accumulation as a function of depth; staining for these matrix molecules showed intense localization in the surface regions. These findings point to the potential of sliding contact to produce engineered cartilage constructs that begin to recapitulate the complex mechanical features of the native tissue.

  4. 28 CFR 810.1 - Supervision contact requirements.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Supervision contact requirements. 810.1 Section 810.1 Judicial Administration COURT SERVICES AND OFFENDER SUPERVISION AGENCY FOR THE DISTRICT OF COLUMBIA COMMUNITY SUPERVISION: ADMINISTRATIVE SANCTIONS § 810.1 Supervision contact requirements. If you are an offender under supervision by th...

  5. Requirements for VICTORIA Class Fire Control System: Contact Management Function

    Science.gov (United States)

    2014-07-01

    Requirements for VICTORIA Class Fire Control System Contact Management Function Tab Lamoureux CAE Integrated Enterprise Solutions...Contract Report DRDC-RDDC-2014-C190 July 2014 © Her Majesty the Queen in Right of Canada, as represented by the...i Abstract …….. The VICTORIA Class Submarines (VCS) are subject to a continuing program of technical upgrades. One such program is

  6. Neural Crest-Derived Mesenchymal Cells Require Wnt Signaling for Their Development and Drive Invagination of the Telencephalic Midline

    Science.gov (United States)

    Choe, Youngshik; Zarbalis, Konstantinos S.; Pleasure, Samuel J.

    2014-01-01

    Embryonic neural crest cells contribute to the development of the craniofacial mesenchyme, forebrain meninges and perivascular cells. In this study, we investigated the function of ß-catenin signaling in neural crest cells abutting the dorsal forebrain during development. In the absence of ß-catenin signaling, neural crest cells failed to expand in the interhemispheric region and produced ectopic smooth muscle cells instead of generating dermal and calvarial mesenchyme. In contrast, constitutive expression of stabilized ß-catenin in neural crest cells increased the number of mesenchymal lineage precursors suggesting that ß-catenin signaling is necessary for the expansion of neural crest-derived mesenchymal cells. Interestingly, the loss of neural crest-derived mesenchymal stem cells (MSCs) leads to failure of telencephalic midline invagination and causes ventricular system defects. This study shows that ß-catenin signaling is required for the switch of neural crest cells to MSCs and mediates the expansion of MSCs to drive the formation of mesenchymal structures of the head. Furthermore, loss of these structures causes striking defects in forebrain morphogenesis. PMID:24516524

  7. Neural crest-derived mesenchymal cells require Wnt signaling for their development and drive invagination of the telencephalic midline.

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    Youngshik Choe

    Full Text Available Embryonic neural crest cells contribute to the development of the craniofacial mesenchyme, forebrain meninges and perivascular cells. In this study, we investigated the function of ß-catenin signaling in neural crest cells abutting the dorsal forebrain during development. In the absence of ß-catenin signaling, neural crest cells failed to expand in the interhemispheric region and produced ectopic smooth muscle cells instead of generating dermal and calvarial mesenchyme. In contrast, constitutive expression of stabilized ß-catenin in neural crest cells increased the number of mesenchymal lineage precursors suggesting that ß-catenin signaling is necessary for the expansion of neural crest-derived mesenchymal cells. Interestingly, the loss of neural crest-derived mesenchymal stem cells (MSCs leads to failure of telencephalic midline invagination and causes ventricular system defects. This study shows that ß-catenin signaling is required for the switch of neural crest cells to MSCs and mediates the expansion of MSCs to drive the formation of mesenchymal structures of the head. Furthermore, loss of these structures causes striking defects in forebrain morphogenesis.

  8. 78 FR 77608 - Requirements for Contacts with Federal Credit Unions

    Science.gov (United States)

    2013-12-24

    ... an FCU official, NCUA has no way of ensuring the environment is safe for its employees or conducive to working efficiently and securely. NCUA staff who have conducted on-site contacts in homes have... other FCU contacts occur in a professional and safe setting. \\5\\ Id. 1766(j)(1). \\6\\ Id. 1789(a)(4). 3...

  9. Inflammasome-independent NLRP3 is required for epithelial-mesenchymal transition in colon cancer cells.

    Science.gov (United States)

    Wang, Hong; Wang, Yajing; Du, Qianming; Lu, Ping; Fan, Huimin; Lu, Jinrong; Hu, Rong

    2016-03-15

    Inflammasome NLRP3 plays a crucial role in the process of colitis and colitis--associated colon cancer. Even though much is known regarding the NLRP3 inflammasome that regulates pro-inflammatory cytokine release in innate immune cells, the role of NLRP3 in non-immune cells is still unclear. In this study, we showed that NLRP3 was highly expressed in mesenchymal-like colon cancer cells (SW620), and was upregulated by tumor necrosis factors-α (TNF-α) and transforming growth factor-β1 (TGF-β1) respectively, during EMT in colon cancer epithelial cells HCT116 and HT29. Knockdown of NLRP3 retained epithelial spindle-like morphology of HCT116 and HT29 cells and reversed the mesenchymal characteristic of SW620 cells, indicated by the decreased expression of vimentin and MMP9 and increased expression of E-cadherin. In addition, knockdown of NLRP3 in colorectal carcinoma cells displayed diminished cell migration and invasion. Interestingly, during the EMT process induced by TNF-α or TGF-β1, the cleaved caspase-1 and ASC speck were not detected, indicating that NLRP3 functions in an inflammasome-independent way. Further studies demonstrated that NLRP3 protein expression was regulated by NF-κB signaling in TNF-α or TGF-β1-induced EMT, as verified by the NF-κB inhibitor Bay 11-7082. Moreover, NLRP3 knockdown reduced the expression of Snail1, indicating that NLRP3 may promote EMT through regulating Snail1. In summary, our results showed that the NLRP3 expression, not the inflammasome activation, was required for EMT in colorectal cancer cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Pdlim7 is required for maintenance of the mesenchymal/epidermal Fgf signaling feedback loop during zebrafish pectoral fin development

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    Klosowiak Julian

    2010-10-01

    Full Text Available Abstract Background Vertebrate limb development involves a reciprocal feedback loop between limb mesenchyme and the overlying apical ectodermal ridge (AER. Several gene pathways participate in this feedback loop, including Fgf signaling. In the forelimb lateral plate mesenchyme, Tbx5 activates Fgf10 expression, which in turn initiates and maintains the mesenchyme/AER Fgf signaling loop. Recent findings have revealed that Tbx5 transcriptional activity is regulated by dynamic nucleocytoplasmic shuttling and interaction with Pdlim7, a PDZ-LIM protein family member, along actin filaments. This Tbx5 regulation is critical in heart formation, but the coexpression of both proteins in other developing tissues suggests a broader functional role. Results Knock-down of Pdlim7 function leads to decreased pectoral fin cell proliferation resulting in a severely stunted fin phenotype. While early gene induction and patterning in the presumptive fin field appear normal, the pectoral fin precursor cells display compaction and migration defects between 18 and 24 hours post-fertilization (hpf. During fin growth fgf24 is sequentially expressed in the mesenchyme and then in the apical ectodermal ridge (AER. However, in pdlim7 antisense morpholino-treated embryos this switch of expression is prevented and fgf24 remains ectopically active in the mesenchymal cells. Along with the lack of fgf24 in the AER, other critical factors including fgf8 are reduced, suggesting signaling problems to the underlying mesenchyme. As a consequence of perturbed AER function in the absence of Pdlim7, pathway components in the fin mesenchyme are misregulated or absent, indicating a breakdown of the Fgf signaling feedback loop, which is ultimately responsible for the loss of fin outgrowth. Conclusion This work provides the first evidence for the involvement of Pdlim7 in pectoral fin development. Proper fin outgrowth requires fgf24 downregulation in the fin mesenchyme with subsequent

  11. Endometrial stromal beta-catenin is required for steroid-dependent mesenchymal-epithelial cross talk and decidualization

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    Zhang Ling

    2012-09-01

    Full Text Available Abstract Background Beta-catenin is part of a protein complex associated with adherens junctions. When allowed to accumulate to sufficient levels in its dephosphorylated form, beta-catenin serves as a transcriptional co-activator associated with a number of signaling pathways, including steroid hormone signaling pathways. Methods To investigate the role of beta-catenin in progesterone (P4 signaling and female reproductive physiology, conditional ablation of Ctnnb1 from the endometrial mesenchymal (i.e. stromal and myometrial, but not epithelial, compartment was accomplished using the Amhr2-Cre mice. Experiments were conducted to assess the ability of mutant female mice to undergo pregnancy and pseudopregnancy by or through oil-induced decidualization. The ability of uteri from mutant female mice to respond to estrogen (E2 and P4 was also determined. Results Conditional deletion of Ctnnb1 from the mesenchymal compartment of the uterus resulted in infertility stemming, in part, from complete failure of the uterus to decidualize. E2-stimulated epithelial cell mitosis and edematization were not altered in mutant uteri indicating that the mesenchyme is capable of responding to E2. However, exposure of ovariectomized mutant female mice to a combined E2 and P4 hormone regimen consistent with early pregnancy revealed that mesenchymal beta-catenin is essential for indirectly opposing E2-induced epithelial proliferation by P4 and in some mice resulted in development of endometrial metaplasia. Lastly, beta-catenin is also required for the induced expression of genes that are known to play a fundamental role in decidualization such as Ihh, Ptch1, Gli1 and Muc1 Conclusions Three salient points derive from these studies. First, the findings demonstrate a mechanistic linkage between the P4 and beta-catenin signaling pathways. Second, they highlight an under appreciated role for the mesenchymal compartment in indirectly mediating P4 signaling to the epithelium

  12. Reactive Oxygen Species Are Required for Human Mesenchymal Stem Cells to Initiate Proliferation after the Quiescence Exit

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    O. G. Lyublinskaya

    2015-01-01

    Full Text Available The present study focuses on the involvement of reactive oxygen species (ROS in the process of mesenchymal stem cells “waking up” and entering the cell cycle after the quiescence. Using human endometrial mesenchymal stem cells (eMSCs, we showed that intracellular basal ROS level is positively correlated with the proliferative status of the cell cultures. Our experiments with the eMSCs synchronized in the G0 phase of the cell cycle revealed a transient increase in the ROS level upon the quiescence exit after stimulation of the cell proliferation. This increase was registered before the eMSC entry to the S-phase of the cell cycle, and elimination of this increase by antioxidants (N-acetyl-L-cysteine, Tempol, and Resveratrol blocked G1–S-phase transition. Similarly, a cell cycle arrest which resulted from the antioxidant treatment was observed in the experiments with synchronized human mesenchymal stem cells derived from the adipose tissue. Thus, we showed that physiologically relevant level of ROS is required for the initiation of human mesenchymal stem cell proliferation and that low levels of ROS due to the antioxidant treatment can block the stem cell self-renewal.

  13. Adenosinergic Immunosuppression by Human Mesenchymal Stromal Cells Requires Co-Operation with T cells.

    Science.gov (United States)

    Kerkelä, Erja; Laitinen, Anita; Räbinä, Jarkko; Valkonen, Sami; Takatalo, Maarit; Larjo, Antti; Veijola, Johanna; Lampinen, Milla; Siljander, Pia; Lehenkari, Petri; Alfthan, Kaija; Laitinen, Saara

    2016-03-01

    Mesenchymal stem/stromal cells (MSCs) have the capacity to counteract excessive inflammatory responses. MSCs possess a range of immunomodulatory mechanisms, which can be deployed in response to signals in a particular environment and in concert with other immune cells. One immunosuppressive mechanism, not so well-known in MSCs, is mediated via adenosinergic pathway by ectonucleotidases CD73 and CD39. In this study, we demonstrate that adenosine is actively produced from adenosine 5'-monophosphate (AMP) by CD73 on MSCs and MSC-derived extracellular vesicles (EVs). Our results indicate that although MSCs express CD39 at low level and it colocalizes with CD73 in bulge areas of membranes, the most efficient adenosine production from adenosine 5'-triphosphate (ATP) requires co-operation of MSCs and activated T cells. Highly CD39 expressing activated T cells produce AMP from ATP and MSCs produce adenosine from AMP via CD73 activity. Furthermore, adenosinergic signaling plays a role in suppression of T cell proliferation in vitro. In conclusion, this study shows that adenosinergic signaling is an important immunoregulatory mechanism of MSCs, especially in situations where ATP is present in the extracellular environment, like in tissue injury. An efficient production of immunosuppressive adenosine is dependent on the concerted action of CD39-positive immune cells with CD73-positive cells such as MSCs or their EVs. © 2016 AlphaMed Press.

  14. Neural crest stem cell multipotency requires Foxd3 to maintain neural potential and repress mesenchymal fates.

    Science.gov (United States)

    Mundell, Nathan A; Labosky, Patricia A

    2011-02-01

    Neural crest (NC) progenitors generate a wide array of cell types, yet molecules controlling NC multipotency and self-renewal and factors mediating cell-intrinsic distinctions between multipotent versus fate-restricted progenitors are poorly understood. Our earlier work demonstrated that Foxd3 is required for maintenance of NC progenitors in the embryo. Here, we show that Foxd3 mediates a fate restriction choice for multipotent NC progenitors with loss of Foxd3 biasing NC toward a mesenchymal fate. Neural derivatives of NC were lost in Foxd3 mutant mouse embryos, whereas abnormally fated NC-derived vascular smooth muscle cells were ectopically located in the aorta. Cranial NC defects were associated with precocious differentiation towards osteoblast and chondrocyte cell fates, and individual mutant NC from different anteroposterior regions underwent fate changes, losing neural and increasing myofibroblast potential. Our results demonstrate that neural potential can be separated from NC multipotency by the action of a single gene, and establish novel parallels between NC and other progenitor populations that depend on this functionally conserved stem cell protein to regulate self-renewal and multipotency.

  15. Hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage.

    Science.gov (United States)

    Frid, Maria G; Brunetti, Jacqueline A; Burke, Danielle L; Carpenter, Todd C; Davie, Neil J; Reeves, John T; Roedersheimer, Mark T; van Rooijen, Nico; Stenmark, Kurt R

    2006-02-01

    Vascular remodeling in chronic hypoxic pulmonary hypertension includes marked fibroproliferative changes in the pulmonary artery (PA) adventitia. Although resident PA fibroblasts have long been considered the primary contributors to these processes, we tested the hypothesis that hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage, termed fibrocytes. Using two neonatal animal models (rats and calves) of chronic hypoxic pulmonary hypertension, we demonstrated a dramatic perivascular accumulation of mononuclear cells of a monocyte/macrophage lineage (expressing CD45, CD11b, CD14, CD68, ED1, ED2). Many of these cells produced type I collagen, expressed alpha-smooth muscle actin, and proliferated, thus exhibiting mesenchymal cell characteristics attributed to fibrocytes. The blood-borne origin of these cells was confirmed in experiments wherein circulating monocytes/macrophages of chronically hypoxic rats were in vivo-labeled with DiI fluorochrome via liposome delivery and subsequently identified in the remodeled pulmonary, but not systemic, arterial adventitia. The DiI-labeled cells that appeared in the vessel wall expressed monocyte/macrophage markers and procollagen. Selective depletion of this monocytic cell population, using either clodronate-liposomes or gadolinium chloride, prevented pulmonary adventitial remodeling (ie, production of collagen, fibronectin, and tenascin-C and accumulation of myofibroblasts). We conclude that circulating mesenchymal precursors of a monocyte/macrophage lineage, including fibrocytes, are essential contributors to hypoxia-induced pulmonary vascular remodeling.

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

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    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.

  17. Mortalin antibody-conjugated quantum dot transfer from human mesenchymal stromal cells to breast cancer cells requires cell–cell interaction

    Energy Technology Data Exchange (ETDEWEB)

    Pietilä, Mika [National Institute of Advanced industrial Sciences and Technology, Tsukuba, Ibaraki 305 8562 (Japan); Lehenkari, Petri [Institute of Biomedicine, Department of Anatomy and Cell Biology, University of Oulu, Aapistie 7, P.O. Box 5000, FIN-90014 (Finland); Institute of Clinical Medicine, Division of Surgery, University of Oulu and Clinical Research Centre, Department of Surgery and Intensive Care, Oulu University Hospital, Aapistie 5a, P.O. Box 5000, FIN-90014 (Finland); Kuvaja, Paula [Institute of Biomedicine, Department of Anatomy and Cell Biology, University of Oulu, Aapistie 7, P.O. Box 5000, FIN-90014 (Finland); Department of Pathology, Oulu University Hospital, P.O. Box 50, FIN-90029 OYS, Oulu (Finland); Kaakinen, Mika [Biocenter Oulu, University of Oulu, P.O. Box 5000, FI-90014 (Finland); Kaul, Sunil C.; Wadhwa, Renu [National Institute of Advanced industrial Sciences and Technology, Tsukuba, Ibaraki 305 8562 (Japan); Uemura, Toshimasa, E-mail: t.uemura@aist.go.jp [National Institute of Advanced industrial Sciences and Technology, Tsukuba, Ibaraki 305 8562 (Japan)

    2013-11-01

    The role of tumor stroma in regulation of breast cancer growth has been widely studied. However, the details on the type of heterocellular cross-talk between stromal and breast cancer cells (BCCs) are still poorly known. In the present study, in order to investigate the intercellular communication between human mesenchymal stromal cells (hMSCs) and breast cancer cells (BCCs, MDA-MB-231), we recruited cell-internalizing quantum dots (i-QD) generated by conjugation of cell-internalizing anti-mortalin antibody and quantum dots (QD). Co-culture of illuminated and color-coded hMSCs (QD655) and BCCs (QD585) revealed the intercellular transfer of QD655 signal from hMSCs to BCCs. The amount of QD double positive BCCs increased gradually within 48 h of co-culture. We found prominent intercellular transfer of QD655 in hanging drop co-culture system and it was non-existent when hMSCs and BBCs cells were co-cultured in trans-well system lacking imminent cell–cell contact. Fluorescent and electron microscope analyses also supported that the direct cell-to-cell interactions may be required for the intercellular transfer of QD655 from hMSCs to BCCs. To the best of our knowledge, the study provides a first demonstration of transcellular crosstalk between stromal cells and BCCs that involve direct contact and may also include a transfer of mortalin, an anti-apoptotic and growth-promoting factor enriched in cancer cells.

  18. Epithelial mesenchymal transition is required for acquisition of anoikis resistance and metastatic potential in adenoid cystic carcinoma.

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    Jun Jia

    Full Text Available Human adenoid cystic carcinoma (ACC is characterized by diffused invasion of the tumor into adjacent organs and early distant metastasis. Anoikis resistance and epithelial mesenchymal transition (EMT are considered prerequisites for cancer cells to metastasize. Exploring the relationship between these processes and their underlying mechanism of action is a promising way to better understand ACC tumors. We initially established anoikis-resistant sublines of ACC cells; the variant cells revealed a mesenchymal phenotype through Slug-mediated EMT-like transformation and displayed enhanced metastatic potential both in vitro and in vivo. Suppression of EMT by knockdown of Slug significantly impaired anoikis resistance, migration, and invasion of the variant cells. With overexpression of Slug and Twist, we determined that induction of EMT in normal ACC cells could prevent anoikis, albeit partially. These findings strongly suggest that EMT is indispensable in anoikis resistance, at least in ACC cells. Furthermore, we found that the EGFR/PI3K/Akt pathway acts as the common regulator for EMT-like transformation and anoikis resistance, as confirmed by their specific inhibitors. Gefitinib and LY294003 restored the sensibilities of anoikis-resistant cells to anoikis and simultaneously impaired their metastatic potential. In addition, the results from our in vivo model of metastasis suggest that pretreatment with gefitinib promotes mouse survival by alleviating pulmonary metastasis. Most importantly, immunohistochemistry of human ACC specimens showed a correlation between the overexpression of Slug and EGFR staining. This study has demonstrated that Slug-mediated EMT-like transformation is required by human ACC cells to achieve anoikis resistance and their metastatic potential. Targeting the EGFR/PI3K/Akt pathway holds potential as a preventive strategy against distant metastasis of ACC.

  19. Bone marrow-derived mesenchymal stem cells propagate immunosuppressive/anti-inflammatory macrophages in cell-to-cell contact-independent and -dependent manners under hypoxic culture.

    Science.gov (United States)

    Takizawa, Naoki; Okubo, Naoto; Kamo, Masaharu; Chosa, Naoyuki; Mikami, Toshinari; Suzuki, Keita; Yokota, Seiji; Ibi, Miho; Ohtsuka, Masato; Taira, Masayuki; Yaegashi, Takashi; Ishisaki, Akira; Kyakumoto, Seiko

    2017-09-15

    Immunosuppressive/anti-inflammatory macrophage (Mφ), M2-Mφ that expressed the typical M2-Mφs marker, CD206, and anti-inflammatory cytokine, interleukin (IL)-10, is beneficial and expected tool for the cytotherapy against inflammatory diseases. Here, we demonstrated that bone marrow-derived lineage-positive (Lin+) blood cells proliferated and differentiated into M2-Mφs by cooperation with the bone marrow-derived mesenchymal stem cells (MSCs) under hypoxic condition: MSCs not only promoted proliferation of undifferentiated M2-Mφs, pre-M2-Mφs, in the Lin+ fraction via a proliferative effect of the MSCs-secreted macrophage colony-stimulating factor, but also promoted M2-Mφ polarization of the pre-M2-Mφs through cell-to-cell contact with the pre-M2-Mφs. Intriguingly, an inhibitor for intercellular adhesion molecule (ICAM)-1 receptor/lymphocyte function-associated antigen (LFA)-1, Rwj50271, partially suppressed expression of CD206 in the Lin+ blood cells but an inhibitor for VCAM-1 receptor/VLA-4, BIO5192, did not, suggesting that the cell-to-cell adhesion through LFA-1 on pre-M2-Mφs and ICAM-1 on MSCs was supposed to promoted the M2-Mφ polarization. Thus, the co-culture system consisting of bone marrow-derived Lin+ blood cells and MSCs under hypoxic condition was a beneficial supplier of a number of M2-Mφs, which could be clinically applicable to inflammatory diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Lactobacilli require physical contact to reduce staphylococcal TSST-1 secretion and vaginal epithelial inflammatory response.

    Science.gov (United States)

    Younes, Jessica A; Reid, Gregor; van der Mei, Henny C; Busscher, Henk J

    2016-06-01

    ITALIC! Staphylococcus aureusbiofilms can be found on vaginal epithelia, secreting toxins and causing inflammation. The co-vaginal species ITALIC! Lactobacilluscan alter staphylococcal-induced epithelial secretion of inflammatory cytokines and quench staphylococcal toxic shock syndrome toxin-1 secretion. It is hypothesized that these effects of lactobacilli require direct physical contact between lactobacilli, staphylococci and the epithelium. Indeed, lactobacilli only reduced ITALIC! S. aureus-induced inflammatory cytokine expression when allowed physical contact with vaginal epithelial cells. Furthermore, a reduction in toxic shock syndrome toxin-1 secretion only occurred when a probiotic ITALIC! Lactobacillusstrain was allowed contact, but not when being physically separated from ITALIC! S. aureus Bacterial-probe atomic force microscopy demonstrated that lactobacilli and staphylococci strongly adhere to epithelial cells, while lactobacilli adhere stronger to staphylococci than staphylococci to each other, giving lactobacilli opportunity to penetrate and reside in staphylococcal biofilms, as visualized using confocal laser scanning microscopy with fluorescence ITALIC! in situhybridization probes. These results identify that physical contact and biochemical signaling by lactobacilli are intrinsically linked mechanisms that reduce virulence of ITALIC! S. aureusbiofilm. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Streptococcus pneumoniae eradicates preformed Staphylococcus aureus biofilms through a mechanism requiring physical contact

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    Faidad Khan

    2016-09-01

    Full Text Available Staphylococcus aureus (Sau strains are a main cause of disease, including nosocomial infections which have been linked to the production of biofilms and the propagation of antibiotic resistance strains such as methicillin-resistant Staphylococcus aureus (MRSA. A previous study found that Streptococcus pneumoniae (Spn strains kill planktonic cultures of Sau strains. In this work, we have further evaluated in detail the eradication of Sau biofilms and investigated ultrastructural interactions of the biofilmicidal effect. Spn strain D39, which produces the competence stimulating peptide 1 (CSP1, reduced Sau biofilms within 8 h of inoculation, while TIGR4, producing CSP2, eradicated Sau biofilms and planktonic cells within 4 h. Differences were not attributed to pherotypes as other Spn strains producing different pheromones eradicated Sau within 4 h. Experiments using Transwell devices, which physically separated both species growing in the same well, demonstrated that direct contact between Spn and Sau was required to efficiently eradicate Sau biofilms and biofilm-released planktonic cells. Physical contact-mediated killing of Sau was not related to production of hydrogen peroxide as an isogenic TIGR4spxB mutant eradicated Sau bacteria within 4 h. Confocal micrographs confirmed eradication of Sau biofilms by TIGR4 and allowed us to visualize ultrastructural point of contacts between Sau and Spn. A time-course study further demonstrated spatial colocalization of Spn chains and Sau tetrads as early as 30 min post-inoculation (Pearson’s coefficient >0.72. Finally, precolonized biofilms produced by Sau strain Newman, or MRSA strain USA300, were eradicated by mid-log phase cultures of washed TIGR4 bacteria within 2 h post-inoculation. In conclusion, Spn strains rapidly eradicate pre-colonized Sau aureus biofilms, including those formed by MRSA strains, by a mechanism(s requiring bacterium-bacterium contact, but independent from the production of

  2. Uterine mesenchymal tumors

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    Nikhil A Sangle

    2011-01-01

    Full Text Available Uterine mesenchymal tumors are a heterogeneous group of neoplasms that can frequently be diagnostically challenging. Differentiation between the benign and malignant counterparts of mesenchymal tumors is significant due to differences in clinical outcome, and the role of the surgical pathologist in making this distinction (especially in the difficult cases cannot be underestimated. Although immunohistochemical stains are supportive toward establishing a final diagnosis, the morphologic features trump all the other ancillary techniques for this group of neoplasms. This review therefore emphasizes the key morphologic features required to diagnose and distinguish uterine mesenchymal tumors from their mimics, with a brief description of the relevant immunohistochemical features.

  3. Suppression of IL-10 production by activated B cells via a cell contact-dependent cyclooxygenase-2 pathway upregulated in IFN-γ-treated mesenchymal stem cells

    Czech Academy of Sciences Publication Activity Database

    Heřmánková, Barbora; Zajícová, Alena; Javorková, Eliška; Chudíčková, Milada; Trošan, Peter; Hájková, Michaela; Krulová, Magdaléna; Holáň, Vladimír

    2016-01-01

    Roč. 221, č. 2 (2016), s. 129-136 ISSN 0171-2985 R&D Projects: GA MŠk(CZ) LO1309; GA ČR(CZ) GA14-12580S; GA MZd NT14102; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:68378041 Keywords : B cells * Cyclooxygenase-2 * IL-10 production * Mesenchymal stem cells * Cyclooxygenase-2 * Immunosuppression Subject RIV: FF - HEENT, Dentistry Impact factor: 2.720, year: 2016

  4. Non-Contact Temperature Requirements (NCTM) for drop and bubble physics

    Science.gov (United States)

    Hmelo, Anthony B.; Wang, Taylor G.

    1989-01-01

    Many of the materials research experiments to be conducted in the Space Processing program require a non-contaminating method of manipulating and controlling weightless molten materials. In these experiments, the melt is positioned and formed within a container without physically contacting the container's wall. An acoustic method, which was developed by Professor Taylor G. Wang before coming to Vanderbilt University from the Jet Propulsion Laboratory, has demonstrated the capability of positioning and manipulating room temperature samples. This was accomplished in an earth-based laboratory with a zero-gravity environment of short duration. However, many important facets of high temperature containerless processing technology have not been established yet, nor can they be established from the room temperature studies, because the details of the interaction between an acoustic field an a molten sample are largely unknown. Drop dynamics, bubble dynamics, coalescence behavior of drops and bubbles, electromagnetic and acoustic levitation methods applied to molten metals, and thermal streaming are among the topics discussed.

  5. Direct Cell-Cell Contact between Mesenchymal Stem Cells and Endothelial Progenitor Cells Induces a Pericyte-Like Phenotype In Vitro

    Directory of Open Access Journals (Sweden)

    Markus Loibl

    2014-01-01

    Full Text Available Tissue engineering techniques for the regeneration of large bone defects require sufficient vascularisation of the applied constructs to ensure a sufficient supply of oxygen and nutrients. In our previous work, prevascularised 3D scaffolds have been successfully established by coculture of bone marrow derived stem cells (MSCs and endothelial progenitor cells (EPCs. We identified stabilising pericytes (PCs as part of newly formed capillary-like structures. In the present study, we report preliminary data on the interactions between MSCs and EPCs, leading to the differentiation of pericyte-like cells. MSCs and EPCs were seeded in transwell cultures, direct cocultures, and single cultures. Cells were cultured for 10 days in IMDM 10% FCS or IMDM 5% FCS 5% platelet lysate medium. Gene expression of PC markers, CD146, NG2, αSMA, and PDGFR-β, was analysed using RT-PCR at days 0, 3, 7, and 10. The upregulation of CD146, NG2, and αSMA in MSCs in direct coculture with EPCs advocates the MSCs’ differentiation towards a pericyte-like phenotype in vitro. These results suggest that pericyte-like cells derive from MSCs and that cell-cell contact with EPCs is an important factor for this differentiation process. These findings emphasise the concept of coculture strategies to promote angiogenesis for cell-based tissue engineered bone grafts.

  6. Recent trends in epidemiology, sensitization and legal requirements of selected relevant contact allergens

    DEFF Research Database (Denmark)

    Schwensen, Jakob F; Bregnbak, David; Johansen, Jeanne Duus

    2016-01-01

    the last 5 years, a comprehensive review of methylisothiazolinone, chromium, cobalt, rubber accelerators and fragrance ingredients were conducted. Of each allergen we discuss in detail the temporal trend of prevalence, source of exposure, clinical manifestation of allergic contact dermatitis...

  7. Determination of Waste Isolation Pilot Plant (WIPP) management and institutional requirements documents for contact-handled (CH) critical systems

    International Nuclear Information System (INIS)

    1990-01-01

    This document lists the critical requirements documents applicable to the receipt of contact-handled waste at the Waste Isolation Pilot Plant. It also describes the processes used to determine the applicability of each document. This analysis is based on the applicable documents that were in effect in the February 1988 time frame. 2 refs

  8. Hematopoietic Stem and Progenitor Cell Expansion in Contact with Mesenchymal Stromal Cells in a Hanging Drop Model Uncovers Disadvantages of 3D Culture

    Directory of Open Access Journals (Sweden)

    Olga Schmal

    2016-01-01

    Full Text Available Efficient ex vivo expansion of hematopoietic stem cells with a concomitant preservation of stemness and self-renewal potential is still an unresolved ambition. Increased numbers of methods approaching this issue using three-dimensional (3D cultures were reported. Here, we describe a simplified 3D hanging drop model for the coculture of cord blood-derived CD34+ hematopoietic stem and progenitor cells (HSPCs with bone marrow-derived mesenchymal stromal cells (MSCs. When seeded as a mixed cell suspension, MSCs segregated into tight spheroids. Despite the high expression of niche-specific extracellular matrix components by spheroid-forming MSCs, HSPCs did not migrate into the spheroids in the initial phase of coculture, indicating strong homotypic interactions of MSCs. After one week, however, HSPC attachment increased considerably, leading to spheroid collapse as demonstrated by electron microscopy and immunofluorescence staining. In terms of HSPC proliferation, the conventional 2D coculture system was superior to the hanging drop model. Furthermore, expansion of primitive hematopoietic progenitors was more favored in 2D than in 3D, as analyzed in colony-forming assays. Conclusively, our data demonstrate that MSCs, when arranged with a spread (monolayer shape, exhibit better HSPC supportive qualities than spheroid-forming MSCs. Therefore, 3D systems are not necessarily superior to traditional 2D culture in this regard.

  9. Hematopoietic Stem and Progenitor Cell Expansion in Contact with Mesenchymal Stromal Cells in a Hanging Drop Model Uncovers Disadvantages of 3D Culture.

    Science.gov (United States)

    Schmal, Olga; Seifert, Jan; Schäffer, Tilman E; Walter, Christina B; Aicher, Wilhelm K; Klein, Gerd

    2016-01-01

    Efficient ex vivo expansion of hematopoietic stem cells with a concomitant preservation of stemness and self-renewal potential is still an unresolved ambition. Increased numbers of methods approaching this issue using three-dimensional (3D) cultures were reported. Here, we describe a simplified 3D hanging drop model for the coculture of cord blood-derived CD34(+) hematopoietic stem and progenitor cells (HSPCs) with bone marrow-derived mesenchymal stromal cells (MSCs). When seeded as a mixed cell suspension, MSCs segregated into tight spheroids. Despite the high expression of niche-specific extracellular matrix components by spheroid-forming MSCs, HSPCs did not migrate into the spheroids in the initial phase of coculture, indicating strong homotypic interactions of MSCs. After one week, however, HSPC attachment increased considerably, leading to spheroid collapse as demonstrated by electron microscopy and immunofluorescence staining. In terms of HSPC proliferation, the conventional 2D coculture system was superior to the hanging drop model. Furthermore, expansion of primitive hematopoietic progenitors was more favored in 2D than in 3D, as analyzed in colony-forming assays. Conclusively, our data demonstrate that MSCs, when arranged with a spread (monolayer) shape, exhibit better HSPC supportive qualities than spheroid-forming MSCs. Therefore, 3D systems are not necessarily superior to traditional 2D culture in this regard.

  10. HEAD INJURIES IN FULL CONTACT KARATE COMPETITION! IS THE PREJUDICE IN MANAGEMENT MINIMISING THE REQUIRED INVESTIGATION?

    OpenAIRE

    Michael R. Graham; Bruce Davies; Julien S. Baker

    2007-01-01

    A 33 year old male karate practitioner presented himself for a full-contact national karate competition. This individual competed for approximately 2 minutes and received a kick to the head. He collapsed in the competitive arena, and suffered a tonic-clonic seizure, lasting for 3 minutes 25 seconds. Examination in the competitive arena revealed an individual who was unconscious. First aid, and paramedic support was provided immediately. Medical assessment identified the presence of vital sign...

  11. Follow-the-leader cell migration requires biased cell-cell contact and local microenvironmental signals

    Science.gov (United States)

    Wynn, Michelle L.; Rupp, Paul; Trainor, Paul A.; Schnell, Santiago; Kulesa, Paul M.

    2013-06-01

    Directed cell migration often involves at least two types of cell motility that include multicellular streaming and chain migration. However, what is unclear is how cell contact dynamics and the distinct microenvironments through which cells travel influence the selection of one migratory mode or the other. The embryonic and highly invasive neural crest (NC) are an excellent model system to study this question since NC cells have been observed in vivo to display both of these types of cell motility. Here, we present data from tissue transplantation experiments in chick and in silico modeling that test our hypothesis that cell contact dynamics with each other and the microenvironment promote and sustain either multicellular stream or chain migration. We show that when premigratory cranial NC cells (at the pre-otic level) are transplanted into a more caudal region in the head (at the post-otic level), cells alter their characteristic stream behavior and migrate in chains. Similarly, post-otic NC cells migrate in streams after transplantation into the pre-otic hindbrain, suggesting that local microenvironmental signals dictate the mode of NC cell migration. Simulations of an agent-based model (ABM) that integrates the NC cell behavioral data predict that chain migration critically depends on the interplay of biased cell-cell contact and local microenvironment signals. Together, this integrated modeling and experimental approach suggests new experiments and offers a powerful tool to examine mechanisms that underlie complex cell migration patterns.

  12. Follow-the-leader cell migration requires biased cell–cell contact and local microenvironmental signals

    International Nuclear Information System (INIS)

    Wynn, Michelle L; Rupp, Paul; Trainor, Paul A; Kulesa, Paul M; Schnell, Santiago

    2013-01-01

    Directed cell migration often involves at least two types of cell motility that include multicellular streaming and chain migration. However, what is unclear is how cell contact dynamics and the distinct microenvironments through which cells travel influence the selection of one migratory mode or the other. The embryonic and highly invasive neural crest (NC) are an excellent model system to study this question since NC cells have been observed in vivo to display both of these types of cell motility. Here, we present data from tissue transplantation experiments in chick and in silico modeling that test our hypothesis that cell contact dynamics with each other and the microenvironment promote and sustain either multicellular stream or chain migration. We show that when premigratory cranial NC cells (at the pre-otic level) are transplanted into a more caudal region in the head (at the post-otic level), cells alter their characteristic stream behavior and migrate in chains. Similarly, post-otic NC cells migrate in streams after transplantation into the pre-otic hindbrain, suggesting that local microenvironmental signals dictate the mode of NC cell migration. Simulations of an agent-based model (ABM) that integrates the NC cell behavioral data predict that chain migration critically depends on the interplay of biased cell–cell contact and local microenvironment signals. Together, this integrated modeling and experimental approach suggests new experiments and offers a powerful tool to examine mechanisms that underlie complex cell migration patterns. (paper)

  13. 76 FR 14825 - Core Principles and Other Requirements for Designated Contact Markets

    Science.gov (United States)

    2011-03-18

    .... All comments must be submitted in English, or if not, accompanied by an English translation. Comments... percentage requirement.'' Discussion of this proposed requirement is available in the notice of proposed...

  14. HEAD INJURIES IN FULL CONTACT KARATE COMPETITION! IS THE PREJUDICE IN MANAGEMENT MINIMISING THE REQUIRED INVESTIGATION?

    Directory of Open Access Journals (Sweden)

    Michael R. Graham

    2007-10-01

    Full Text Available A 33 year old male karate practitioner presented himself for a full-contact national karate competition. This individual competed for approximately 2 minutes and received a kick to the head. He collapsed in the competitive arena, and suffered a tonic-clonic seizure, lasting for 3 minutes 25 seconds. Examination in the competitive arena revealed an individual who was unconscious. First aid, and paramedic support was provided immediately. Medical assessment identified the presence of vital signs. Glasgow coma scale (GCS, post trauma was recorded as 3/15 until the fifth minute. A patent airway was established and a neck brace was applied. Blood pressure within 1 minute of trauma was 195/98 mm.Hg, heart rate was 185 bpm and respiratory rate was 40 breaths·min-1. Oxygen was administered via a ventimask. The patient was conveyed to the medical area. The patient regained consciousness one minute after the seizure had resolved, but had amnesia concerning the event. GCS at five minutes was recorded as 13/15. The patient was transferred by ambulance to the nearest Hospital. The patient was discharged, following examination without further investigation. The finding of this study suggests that an individual with a history of head injury should have received computerised tomography as a minimum investigation. This may help eleviate the risk of further medical complications

  15. Ihh and PTH1R signaling in limb mesenchyme is required for proper segmentation and subsequent formation and growth of digit bones.

    Science.gov (United States)

    Amano, Katsuhiko; Densmore, Michael; Fan, Yi; Lanske, Beate

    2016-02-01

    Digit formation is a process, which requires the proper segmentation, formation and growth of phalangeal bones and is precisely regulated by several important factors. One such factor is Ihh, a gene linked to BDA1 and distal symphalangism in humans. In existing mouse models, mutations in Ihh have been shown to cause multiple synostosis in the digits but lead to perinatal lethality. To better study the exact biological and pathological events which occur in these fused digits, we used a more viable Prx1-Cre;Ihh(fl/fl) model in which Cre recombinase is expressed during mesenchymal condensation in the earliest limb buds at E9.5 dpc and found that mutant digits continuously fuse postnatally until phalanges are finally replaced by an unsegmented "one-stick bone". Mutant mice displayed osteocalcin-positive mature osteoblasts, but had reduced proliferation and abnormal osteogenesis. Because of the close interaction between Ihh and PTHrP during endochondral ossification, we also examined the digits of Prx1-Cre;PTH1R(fl/fl) mice, where the receptor for PTHrP was conditionally deleted. Surprisingly, we found PTH1R deletion caused symphalangism, demonstrating another novel function of PTH1R signaling in digit formation. We characterized the symphalangism process whereby initial cartilaginous fusion prevented epiphyseal growth plate formation, resulting in resorption and replacement of the remaining cartilage by bony tissue. Chondrocyte differentiation displayed abnormal directionality in both mutants. Lastly, Prx1-Cre;Ihh(fl/fl);Jansen Tg mice, in which a constitutively active PTH1R allele was introduced into Ihh mutants, were established to address the possible involvement of PTH1R signaling in Ihh mutant digits. These rescue mice failed to show significantly improved phenotype, suggesting that PTH1R signaling in chondrocytes is not sufficient to restore digit formation. Our results demonstrate that Ihh and PTH1R signaling in limb mesenchyme are both essential to regulate

  16. Differential marker expression by cultures rich in mesenchymal stem cells

    Science.gov (United States)

    2013-01-01

    Background Mesenchymal stem cells have properties that make them amenable to therapeutic use. However, the acceptance of mesenchymal stem cells in clinical practice requires standardized techniques for their specific isolation. To date, there are no conclusive marker (s) for the exclusive isolation of mesenchymal stem cells. Our aim was to identify markers differentially expressed between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. We compared and contrasted the phenotype of tissue cultures in which mesenchymal stem cells are rich and rare. By initially assessing mesenchymal stem cell differentiation, we established that bone marrow and breast adipose cultures are rich in mesenchymal stem cells while, in our hands, foreskin fibroblast and olfactory tissue cultures contain rare mesenchymal stem cells. In particular, olfactory tissue cells represent non-stem cell mesenchymal cells. Subsequently, the phenotype of the tissue cultures were thoroughly assessed using immuno-fluorescence, flow-cytometry, proteomics, antibody arrays and qPCR. Results Our analysis revealed that all tissue cultures, regardless of differentiation potential, demonstrated remarkably similar phenotypes. Importantly, it was also observed that common mesenchymal stem cell markers, and fibroblast-associated markers, do not discriminate between mesenchymal stem cell and non-stem cell mesenchymal cell cultures. Examination and comparison of the phenotypes of mesenchymal stem cell and non-stem cell mesenchymal cell cultures revealed three differentially expressed markers – CD24, CD108 and CD40. Conclusion We indicate the importance of establishing differential marker expression between mesenchymal stem cells and non-stem cell mesenchymal cells in order to determine stem cell specific markers. PMID:24304471

  17. Pancreatic mesenchyme regulates epithelial organogenesis throughout development.

    Directory of Open Access Journals (Sweden)

    Limor Landsman

    2011-09-01

    Full Text Available The developing pancreatic epithelium gives rise to all endocrine and exocrine cells of the mature organ. During organogenesis, the epithelial cells receive essential signals from the overlying mesenchyme. Previous studies, focusing on ex vivo tissue explants or complete knockout mice, have identified an important role for the mesenchyme in regulating the expansion of progenitor cells in the early pancreas epithelium. However, due to the lack of genetic tools directing expression specifically to the mesenchyme, the potential roles of this supporting tissue in vivo, especially in guiding later stages of pancreas organogenesis, have not been elucidated. We employed transgenic tools and fetal surgical techniques to ablate mesenchyme via Cre-mediated mesenchymal expression of Diphtheria Toxin (DT at the onset of pancreas formation, and at later developmental stages via in utero injection of DT into transgenic mice expressing the Diphtheria Toxin receptor (DTR in this tissue. Our results demonstrate that mesenchymal cells regulate pancreatic growth and branching at both early and late developmental stages by supporting proliferation of precursors and differentiated cells, respectively. Interestingly, while cell differentiation was not affected, the expansion of both the endocrine and exocrine compartments was equally impaired. To further elucidate signals required for mesenchymal cell function, we eliminated β-catenin signaling and determined that it is a critical pathway in regulating mesenchyme survival and growth. Our study presents the first in vivo evidence that the embryonic mesenchyme provides critical signals to the epithelium throughout pancreas organogenesis. The findings are novel and relevant as they indicate a critical role for the mesenchyme during late expansion of endocrine and exocrine compartments. In addition, our results provide a molecular mechanism for mesenchymal expansion and survival by identifying β-catenin signaling as an

  18. Scribble is required for normal epithelial cell–cell contacts and lumen morphogenesis in the mammalian lung

    Science.gov (United States)

    Yates, Laura L.; Schnatwinkel, Carsten; Hazelwood, Lee; Chessum, Lauren; Paudyal, Anju; Hilton, Helen; Romero, M. Rosario; Wilde, Jonathan; Bogani, Debora; Sanderson, Jeremy; Formstone, Caroline; Murdoch, Jennifer N.; Niswander, Lee A.; Greenfield, Andy; Dean, Charlotte H.

    2013-01-01

    During lung development, proper epithelial cell arrangements are critical for the formation of an arborized network of tubes. Each tube requires a lumen, the diameter of which must be tightly regulated to enable optimal lung function. Lung branching and lumen morphogenesis require close epithelial cell–cell contacts that are maintained as a result of adherens junctions, tight junctions and by intact apical–basal (A/B) polarity. However, the molecular mechanisms that maintain epithelial cohesion and lumen diameter in the mammalian lung are unknown. Here we show that Scribble, a protein implicated in planar cell polarity (PCP) signalling, is necessary for normal lung morphogenesis. Lungs of the Scrib mouse mutant Circletail (Crc) are abnormally shaped with fewer airways, and these airways often lack a visible, ‘open’ lumen. Mechanistically we show that Scrib genetically interacts with the core PCP gene Vangl2 in the developing lung and that the distribution of PCP pathway proteins and Rho mediated cytoskeletal modification is perturbed in ScribCrc/Crc lungs. However A/B polarity, which is disrupted in Drosophila Scrib mutants, is largely unaffected. Notably, we find that Scrib mediates functions not attributed to other PCP proteins in the lung. Specifically, Scrib localises to both adherens and tight junctions of lung epithelia and knockdown of Scrib in lung explants and organotypic cultures leads to reduced cohesion of lung epithelial cells. Live imaging of Scrib knockdown lungs shows that Scrib does not affect bud bifurcation, as previously shown for the PCP protein Celsr1, but is required to maintain epithelial cohesion. To understand the mechanism leading to reduced cell–cell association, we show that Scrib associates with β-catenin in embryonic lung and the sub-cellular distribution of adherens and tight junction proteins is perturbed in mutant lung epithelia. Our data reveal that Scrib is required for normal lung epithelial organisation and lumen

  19. TRU [transuranic] waste certification compliance requirements for acceptance of newly generated contact-handled wastes to be shipped to the Waste Isolation Pilot Plant: Revision 2

    International Nuclear Information System (INIS)

    1989-01-01

    Compliance requirements are presented for certifying that unclassified, newly generated (NG), contact-handled (CH) transuranic (TRU) solid wastes from defense programs meet the Waste Isolation Pilot Plant (WIPP) Waste Acceptance Criteria (WAC). Where appropriate, transportation and interim storage requirements are incorporated; however, interim storage sites may have additional requirements consistent with these requirements. All applicable Department of Energy (DOE) orders must continue to be met. The compliance requirements for stored or buried waste are not addressed in this document. The compliance requirements are divided into four sections, primarily determined by the general feature that the requirements address. These sections are General Requirements, Waste Container Requirements, Waste Form Requirements, and Waste Package Requirements. The waste package is the combination of waste container and waste. 10 refs., 1 fig

  20. Mesenchymal stem cells induce dermal fibroblast responses to injury

    International Nuclear Information System (INIS)

    Smith, Andria N.; Willis, Elise; Chan, Vincent T.; Muffley, Lara A.; Isik, F. Frank; Gibran, Nicole S.; Hocking, Anne M.

    2010-01-01

    Although bone marrow-derived mesenchymal stem cells have been shown to promote repair when applied to cutaneous wounds, the mechanism for this response remains to be determined. The aim of this study was to determine the effects of paracrine signaling from mesenchymal stem cells on dermal fibroblast responses to injury including proliferation, migration and expression of genes important in wound repair. Dermal fibroblasts were co-cultured with bone marrow-derived mesenchymal stem cells grown in inserts, which allowed for paracrine interactions without direct cell contact. In this co-culture model, bone marrow-derived mesenchymal stem cells regulate dermal fibroblast proliferation, migration and gene expression. When co-cultured with mesenchymal stem cells, dermal fibroblasts show increased proliferation and accelerated migration in a scratch assay. A chemotaxis assay also demonstrated that dermal fibroblasts migrate towards bone marrow-derived mesenchymal stem cells. A PCR array was used to analyze the effect of mesenchymal stem cells on dermal fibroblast gene expression. In response to mesenchymal stem cells, dermal fibroblasts up-regulate integrin alpha 7 expression and down-regulate expression of ICAM1, VCAM1 and MMP11. These observations suggest that mesenchymal stem cells may provide an important early signal for dermal fibroblast responses to cutaneous injury.

  1. Mesenchymal cells reactivate Snail1 expression to drive three-dimensional invasion programs

    DEFF Research Database (Denmark)

    Rowe, R.G.; Li, X.Y.; Hu, Y.

    2009-01-01

    Epithelial-mesenchymal transition (EMT) is required for mesodermal differentiation during development. The zinc-finger transcription factor, Snail1, can trigger EMT and is sufficient to transcriptionally reprogram epithelial cells toward a mesenchymal phenotype during neoplasia and fibrosis. Whet...

  2. Effects of contact network structure on epidemic transmission trees: implications for data required to estimate network structure.

    Science.gov (United States)

    Carnegie, Nicole Bohme

    2018-01-30

    Understanding the dynamics of disease spread is key to developing effective interventions to control or prevent an epidemic. The structure of the network of contacts over which the disease spreads has been shown to have a strong influence on the outcome of the epidemic, but an open question remains as to whether it is possible to estimate contact network features from data collected in an epidemic. The approach taken in this paper is to examine the distributions of epidemic outcomes arising from epidemics on networks with particular structural features to assess whether that structure could be measured from epidemic data and what other constraints might be needed to make the problem identifiable. To this end, we vary the network size, mean degree, and transmissibility of the pathogen, as well as the network feature of interest: clustering, degree assortativity, or attribute-based preferential mixing. We record several standard measures of the size and spread of the epidemic, as well as measures that describe the shape of the transmission tree in order to ascertain whether there are detectable signals in the final data from the outbreak. The results suggest that there is potential to estimate contact network features from transmission trees or pure epidemic data, particularly for diseases with high transmissibility or for which the relevant contact network is of low mean degree. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... not require the same level of care or consideration as a standard contact lens because they can ... sell contacts without a prescription are breaking the law, and may be fined $11,000 per violation. " ...

  4. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... the United States. All contact lenses are medical devices that require a prescription and proper fitting by an eye-care professional. Retailers that sell contacts without a ...

  5. Occupational contact urticaria and protein contact dermatitis.

    Science.gov (United States)

    Doutre, Marie-Sylvie

    2005-01-01

    Irritant dermatitis and eczema are the most prevalent occupational skin diseases. Less common are immediate contact reactions such as contact urticaria and protein contact dermatitis. Occupational contact urticaria can be subdivided into two categories, immunological and non immunological. However, some agents can induce these two types of reactions. Contact urticaria to natural rubber latex is particularly frequent among health care personnel, but contact urticaria to a wide variety of other substances occurs in many other occupations. Among those at risk are cooks, bakers, butchers, restaurant personnel, veterinarians, hairdressers, florists, gardeners, and forestry workers. Protein contact dermatitis in some of these occupations is caused principally by proteins of animal or plant origin, especially among individuals with a history of atopic dermatitis. Diagnosis requires careful interrogation, clinical examination and skin tests (open tests and prick tests with immediate lecture) to identify a particular contact allergen.

  6. Activation of β-adrenergic receptors is required for elevated α1A-adrenoreceptors expression and signaling in mesenchymal stromal cells

    Science.gov (United States)

    Tyurin-Kuzmin, Pyotr A.; Fadeeva, Julia I.; Kanareikina, Margarita A.; Kalinina, Natalia I.; Sysoeva, Veronika Yu.; Dyikanov, Daniyar T.; Stambolsky, Dmitriy V.; Tkachuk, Vsevolod A.

    2016-01-01

    Sympathetic neurons are important components of mesenchymal stem cells (MSCs) niche and noradrenaline regulates biological activities of these cells. Here we examined the mechanisms of regulation of MSCs responsiveness to noradrenaline. Using flow cytometry, we demonstrated that α1A adrenergic receptors isoform was the most abundant in adipose tissue-derived MSCs. Using calcium imaging in single cells, we demonstrated that only 6.9 ± 0.8% of MSCs responded to noradrenaline by intracellular calcium release. Noradrenaline increases MSCs sensitivity to catecholamines in a transitory mode. Within 6 hrs after incubation with noradrenaline the proportion of cells responding by Ca2+ release to the fresh noradrenaline addition has doubled but declined to the baseline after 24 hrs. Increased sensitivity was due to the elevated quantities of α1A-adrenergic receptors on MSCs. Such elevation depended on the stimulation of β-adrenergic receptors and adenylate cyclase activation. The data for the first time clarify mechanisms of regulation of MSCs sensitivity to noradrenaline. PMID:27596381

  7. Chromatin organization regulated by EZH2-mediated H3K27me3 is required for OPN-induced migration of bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Liu, Lingling; Luo, Qing; Sun, Jinghui; Ju, Yang; Morita, Yasuyuki; Song, Guanbin

    2018-03-01

    Osteopontin (OPN) is a chemokine-like extracellular matrix-associated protein involved in the migration of bone marrow-derived mesenchymal stem cells (BMSCs). An increasing number of studies have found that chromatin organization may affect cellular migration. However, whether OPN regulates chromatin organization is not understood, nor are the underlying molecular mechanisms. In this study, we investigated the link between chromatin organization and BMSC migration and demonstrated that OPN-mediated BMSC migration leads to elevated levels of heterochromatin marker histone H3 lysine 27 trimethylation (H3K27me3) through the methyltransferase EZH2. The expression of EZH2 reorganizes the chromatin structure of BMSCs. Pharmacological inhibition or depletion of EZH2 blocks BMSC migration. Moreover, using an atomic force microscope (AFM), we found that chromatin decondensation alters the mechanical properties of the nucleus. In addition, inhibition of extracellular signal-regulated kinase 1/2 (ERK1/2) signals represses OPN-promoted chromatin condensation and cell migration. Thus, our results identify a mechanism by which ERK1/2 signalling drives specific chromatin modifications in BMSCs, which alters chromatin organization and thereby enables OPN-mediated BMSC migration. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Language Contact.

    Science.gov (United States)

    Nelde, Peter Hans

    1995-01-01

    Examines the phenomenon of language contact and recent trends in linguistic contact research, which focuses on language use, language users, and language spheres. Also discusses the role of linguistic and cultural conflicts in language contact situations. (13 references) (MDM)

  9. A CD8 T Cell/Indoleamine 2,3-Dioxygenase Axis Is Required for Mesenchymal Stem Cell Suppression of Human Systemic Lupus Erythematosus

    Science.gov (United States)

    Wang, Dandan; Feng, Xuebing; Lu, Lin; Konkel, Joanne E; Zhang, Huayong; Chen, Zhiyong; Li, Xia; Gao, Xiang; Lu, Liwei; Shi, Songtao; Chen, Wanjun; Sun, Lingyun

    2014-01-01

    Objective Allogeneic mesenchymal stem cells (MSCs) exhibit therapeutic effects in human autoimmune diseases such as systemic lupus erythematosus (SLE), but the underlying mechanisms remain largely unknown. The aim of this study was to investigate how allogeneic MSCs mediate immunosuppression in lupus patients. Methods The effects of allogeneic umbilical cord–derived MSCs (UC-MSCs) on inhibition of T cell proliferation were determined. MSC functional molecules were stimulated with peripheral blood mononuclear cells from healthy controls and SLE patients and examined by real-time polymerase chain reaction. CD4+ and CD8+ T cells were purified using microbeads to stimulate MSCs in order to determine cytokine expression by MSCs and to further determine which cell subset(s) or which molecule(s) is involved in inhibition of MSC–mediated T cell proliferation. The related signaling pathways were assessed. We determined levels of serum cytokines in lupus patients before and after UC-MSC transplantation. Results Allogeneic UC-MSCs suppressed T cell proliferation in lupus patients by secreting large amounts of indoleamine 2,3-dioxygenase (IDO). We further found that interferon-γ (IFNγ), which is produced predominantly by lupus CD8+ T cells, is the key factor that enhances IDO activity in allogeneic MSCs and that it is associated with IFNGR1/JAK-2/STAT signaling pathways. Intriguingly, bone marrow–derived MSCs from patients with active lupus demonstrated defective IDO production in response to IFNγ and allogeneic CD8+ T cell stimulation. After allogeneic UC-MSC transplantation, serum IDO activity increased in lupus patients. Conclusion We found a previously unrecognized CD8+ T cell/IFNγ/IDO axis that mediates the therapeutic effects of allogeneic MSCs in lupus patients. PMID:24756936

  10. Synthesis of embryonic tendon-like tissue by human marrow stromal/mesenchymal stem cells requires a three-dimensional environment and transforming growth factor β3.

    Science.gov (United States)

    Kapacee, Zoher; Yeung, Ching-Yan Chloé; Lu, Yinhui; Crabtree, David; Holmes, David F; Kadler, Karl E

    2010-10-01

    Tendon-like tissue generated from stem cells in vitro has the potential to replace tendons and ligaments lost through injury and disease. However, thus far, no information has been available on the mechanism of tendon formation in vitro and how to accelerate the process. We show here that human mesenchymal stem cells (MSCs) and bone marrow-derived mononuclear cells (BM-MNCs) can generate tendon-like tissue in 7days mediated by transforming growth factor (TGF) β3. MSCs cultured in fixed-length fibrin gels spontaneously synthesized narrow-diameter collagen fibrils and exhibited fibripositors (actin-rich, collagen fibril-containing plasma membrane protrusions) identical to those that occur in embryonic tendon. In contrast, BM-MNCs did not synthesize tendon-like tissue under these conditions. We performed real-time PCR analysis of MSCs and BM-MNCs. MSCs upregulated genes encoding type I collagen, TGFβ3, and Smad2 at the time of maximum contraction of the tendon-like tissue (7days). Western blot analysis showed phosphorylation of Smad2 at maximum contraction. The TGFβ inhibitor SB-431542, blocked the phosphorylation of Smad2 and stopped the formation of tendon-like tissue. Quantitative PCR showed that BM-MNCs expressed very low levels of TGFβ3 compared to MSCs. Therefore we added exogenous TGFβ3 protein to BM-MNCs in fibrin gels, which resulted in phosphorylation of Smad2, synthesis of collagen fibrils, the appearance of fibripositors at the plasma membrane, and the formation of tendon-like tissue. In conclusion, MSCs that self-generate TGFβ signaling or the addition of TGFβ3 protein to BM-MNCs in fixed-length fibrin gels spontaneously make embryonic tendon-like tissue in vitro within 7days. Copyright © 2010 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

  11. Immunological characteristics of mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Cíntia de Vasconcellos Machado

    2013-01-01

    Full Text Available Although bone marrow is the main source, mesenchymal stem cells have already been isolated from various other tissues, such as the liver, pancreas, adipose tissue, peripheral blood and dental pulp. These plastic adherent cells are morphologically similar to fibroblasts and have a high proliferative potential. This special group of cells possesses two essential characteristics: self-renewal and differentiation, with appropriate stimuli, into various cell types. Mesenchymal stem cells are considered immunologically privileged, since they do not express costimulatory molecules, required for complete T cell activation, on their surface. Several studies have shown that these cells exert an immunosuppressive effect on cells from both innate and acquired immunity systems. Mesenchymal stem cells can regulate the immune response in vitro by inhibiting the maturation of dendritic cells, as well as by suppressing the proliferation and function of T and B lymphocytes and natural killer cells. These special properties of mesenchymal stem cells make them a promising strategy in the treatment of immune mediated disorders, such as graft-versus-host disease and autoimmune diseases, as well as in regenerative medicine. The understanding of immune regulation mechanisms of mesenchymal stem cells, and also those involved in the differentiation of these cells in various lineages is primordial for their successful and safe application in different areas of medicine.

  12. Co-Culturing of Multipotent Mesenchymal Stromal Cells with Autological and Allogenic Lymphocytes.

    Science.gov (United States)

    Kapranov, N M; Davydova, Yu O; Gal'tseva, I V; Petinati, N A; Bakshinskaitė, M V; Drize, N I; Kuz'mina, L A; Parovichnikova, E N; Savchenko, V G

    2018-03-01

    We studied the effect of autologous and allogeneic lymphocytes on multipotent mesenchymal stromal cells in co-culture. It is shown that changes in multipotent mesenchymal stromal cells and in lymphocytes did not depend on the source of lymphocytes. Contact with lymphocytes triggers expression of HLA-DR molecules on multipotent mesenchymal stromal cells and these cells lose their immune privilege. In multipotent mesenchymal stromal cells, the relative level of expression of factors involved in immunomodulation (IDO1, PTGES, and IL-6) and expression of adhesion molecule ICAM1 increased, while expression of genes involved in the differentiation of multipotent mesenchymal stromal cells remained unchanged. Priming of multipotent mesenchymal stromal cells with IFN did not affect these changes. In turn, lymphocytes underwent activation, expression of HLA-DR increased, subpopulation composition of lymphocytes changed towards the increase in the content of naïve T cells. These findings are important for cell therapy.

  13. Deletion of a conserved regulatory element required for Hmx1 expression in craniofacial mesenchyme in the dumbo rat: a newly identified cause of congenital ear malformation

    Directory of Open Access Journals (Sweden)

    Lely A. Quina

    2012-11-01

    Hmx1 is a homeodomain transcription factor expressed in the developing eye, peripheral ganglia, and branchial arches of avian and mammalian embryos. Recent studies have identified a loss-of-function allele at the HMX1 locus as the causative mutation in the oculo-auricular syndrome (OAS in humans, characterized by ear and eye malformations. The mouse dumbo (dmbo mutation, with similar effects on ear and eye development, also results from a loss-of-function mutation in the Hmx1 gene. A recessive dmbo mutation causing ear malformation in rats has been mapped to the chromosomal region containing the Hmx1 gene, but the nature of the causative allele is unknown. Here we show that dumbo rats and mice exhibit similar neonatal ear and eye phenotypes. In midgestation embryos, dumbo rats show a specific loss of Hmx1 expression in neural-crest-derived craniofacial mesenchyme (CM, whereas Hmx1 is expressed normally in retinal progenitors, sensory ganglia and in CM, which is derived from mesoderm. High-throughput resequencing of 1 Mb of rat chromosome 14 from dmbo/dmbo rats, encompassing the Hmx1 locus, reveals numerous divergences from the rat genomic reference sequence, but no coding changes in Hmx1. Fine genetic mapping narrows the dmbo critical region to an interval of ∼410 kb immediately downstream of the Hmx1 transcription unit. Further sequence analysis of this region reveals a 5777-bp deletion located ∼80 kb downstream in dmbo/dmbo rats that is not apparent in 137 other rat strains. The dmbo deletion region contains a highly conserved domain of ∼500 bp, which is a candidate distal enhancer and which exhibits a similar relationship to Hmx genes in all vertebrate species for which data are available. We conclude that the rat dumbo phenotype is likely to result from loss of function of an ultraconserved enhancer specifically regulating Hmx1 expression in neural-crest-derived CM. Dysregulation of Hmx1 expression is thus a candidate mechanism for congenital ear

  14. Human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem; Kassem, Moustapha

    2008-01-01

    Mesenchymal stem cells (MSC) are a group of clonogenic cells present among the bone marrow stroma and capable of multilineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. Due to their ease of isolation and their differentiation potential, MSC are being...... introduced into clinical medicine in variety of applications and through different ways of administration. Here, we discuss approaches for isolation, characterization and directing differentiation of human mesenchymal stem cells (hMSC). An update of the current clinical use of the cells is also provided....

  15. SAM Technical Contacts

    Science.gov (United States)

    These technical contacts are available to help with questions regarding method deviations, modifications, sample problems or interferences, quality control requirements, the use of alternative methods, or the need to address analytes or sample types.

  16. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... contacto de color Sep. 26, 2013 It started as an impulsive buy from a souvenir shop, but ... require the same level of care or consideration as a standard contact lens because they can be ...

  17. Colored Contact Lens Dangers

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    Full Text Available ... that decorative lenses do not require the same level of care or consideration as a standard contact ... By Kate Rauch In a small but intriguing study, scientists in England have given blind patients some ...

  18. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... had not been properly fitted by an eye care professional, the lenses stuck to my eye like ... lenses do not require the same level of care or consideration as a standard contact lens because ...

  19. Colored Contact Lens Dangers

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    Full Text Available ... the United States. All contact lenses are medical devices that require a prescription and proper fitting by ... Care Apr 23, 2018 How long does it take the eye to go back to its original ...

  20. Colored Contact Lens Dangers

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    Full Text Available ... not require the same level of care or consideration as a standard contact lens because they can ... Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms ...

  1. MicroRNA expression in a phosphaturic mesenchymal tumour

    Directory of Open Access Journals (Sweden)

    Darrell Green

    2017-12-01

    Full Text Available Phosphaturic mesenchymal tumours are a heterogeneous set of bone and soft tissue neoplasms that can cause a number of paraneoplastic syndromes such as tumour induced osteomalacia. The term phosphaturic comes from the common finding that these tumours secrete high levels of fibroblast growth factor 23 which causes renal phosphate wasting leading to hypophosphatemia. Phosphaturic mesenchymal tumours are rare and diagnosis is difficult. A very active 68 year old male presented with bone pain and muscle weakness. He was hypophosphataemic and total alkaline phosphatase was markedly elevated. The patient was placed on vitamin D supplementation but his condition progressed. In the fifth year of presentation the patient required the use of a wheelchair and described “explosive” bone pain on physical contact. Serum 1,25 dihydroxyvitamin D was low and serum fibroblast growth factor 23 was significantly elevated, raising suspicion of a phosphaturic mesenchymal tumour. A lesion was detected in his left femoral head and the patient underwent a total hip replacement. The patient displayed a rapid improvement to his condition and during a three year follow up period he returned to an active lifestyle. As molecular testing may help provide a robust diagnosis and is particularly useful in rare diseases we took a next generation sequencing approach to identify a differential expression of small RNAs in the resected tumour. Small RNAs are non-coding RNA molecules that play a key role in regulation of gene expression and can be used as specific biomarkers. We found an upregulation of miR-197. We also found a downregulation of miR-20b, miR-144 and miR-335 which is a small RNA profile typical of osteosarcoma. MiR-21, the most frequently upregulated microRNA in cancer, was downregulated. We conclude that the specific small RNA profile is typical of osteosarcoma except for the downregulation of oncogenic miR-21. Transcriptional plasticity of miR-197, which is

  2. A Framework for Better Understanding and Enhancing Direct Contact Membrane Distillation (DCMD) in Terms of Module Design, Cost Analysis and Energy Required

    KAUST Repository

    AbuHannoud, Ali

    2011-07-01

    Water is becoming scarcer and several authors have highlighted the upcoming problem of higher water salinity and the difficulty of treating and discharging water. Moreover, current discoveries of problems with chemicals that have been used for pretreating or post-treating water alerted scientists to research better solutions to treat water. Membrane distillation (MD) is a promising technology that might replace current processes as it has lower pretreatment requirements combined with a tremendous ability to treat a wide range of feed sources while producing very high product quality. If it enters the market, it will have a big influence on all products, from food industry to spaceflight. However, there are several problems which make MD a hot topic for research. One of them is the question about the real cost of MD in terms of heating feed and cooling distillate over time with respect to product quantity and quality. In this work, extensive heating and cooling analyses are covered to answer this question in order to enhance the MD process. Results show energy cost to produce water and the main source of energy loss for direct contact membrane distillation (DCMD), and several suggestions are made in order to better understand and hence enhance the process.

  3. Intercellular transfer of P-glycoprotein from the drug resistant human bladder cancer cell line BIU-87 does not require cell-to-cell contact.

    Science.gov (United States)

    Zhou, Hui-liang; Zheng, Yong-jun; Cheng, Xiao-zhi; Lv, Yi-song; Gao, Rui; Mao, Hou-ping; Chen, Qin

    2013-09-01

    The efflux activity of transmembrane P-glycoprotein prevents various therapeutic drugs from reaching lethal concentrations in cancer cells, resulting in multidrug resistance. We investigated whether drug resistant bladder cancer cells could transfer functional P-glycoprotein to sensitive parental cells. Drug sensitive BIU-87 bladder cancer cells were co-cultured for 48 hours with BIU-87/ADM, a doxorubicin resistant derivative of the same cell line, in a Transwell® system that prevented cell-to-cell contact. The presence of P-glycoprotein in recipient cell membranes was established using fluorescein isothiocyanate, laser scanning confocal microscopy and Western blot. P-glycoprotein mRNA levels were compared between cell types. Rhodamine 123 efflux assay was done to confirm that P-glycoprotein was biologically active. The amount of P-glycoprotein protein in BIU-87 cells co-cultured with BIU-87/ADM was significantly higher than in BIU-87 cells (0.44 vs 0.25) and BIU-87/H33342 cells (0.44 vs 0.26, each p transfer. P-glycoprotein mRNA expression was significantly higher in BIU-87/ADM cells than in co-cultured BIU-87 cells (1.28 vs 0.30), BIU-87/H33342 (0.28) and BIU-87 cells (0.25, each p <0.001), ruling out a genetic mechanism. After 30 minutes of efflux, rhodamine 123 fluorescence intensity was significantly lower in BIU-87/ADM cells (5.55 vs 51.45, p = 0.004) and co-cultured BIU-87 cells than in BIU-87 cells (14.22 vs 51.45, p <0.001), indicating that P-glycoprotein was functional. Bladder cancer cells can acquire functional P-glycoprotein through a nongenetic mechanism that does not require direct cell contact. This mechanism is consistent with a microparticle mediated process. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  4. Allergic Contact Dermatitis

    Directory of Open Access Journals (Sweden)

    Meltem Önder

    2009-03-01

    Full Text Available Allergic contact dermatitis is the delayed type hypersensitivity reaction to exogenous agents. Allergic contact dermatitis may clinically present acutely after allergen exposure and initial sensitization in a previously sensitized individual. Acute phase is characterized by erythematous, scaly plaques. In severe cases vesiculation and bullae in exposed areas are very characteristic. Repeated or continuous exposure of sensitized individual with allergen result in chronic dermatitis. Lichenification, erythematous plaques, hyperkeratosis and fissuring may develop in chronic patients. Allergic contact dermatitis is very common dermatologic problem in dermatology daily practice. A diagnosis of contact dermatitis requires the careful consideration of patient history, physical examination and patch testing. The knowledge of the clinical features of the skin reactions to various contactans is important to make a correct diagnosis of contact dermatitis. It can be seen in every age, in children textile product, accessories and touch products are common allergens, while in adults allergic contact dermatitis may be related with topical medicaments. The contact pattern of contact dermatitis depends on fashion and local traditions as well. The localization of allergic reaction should be evaluated and patients’ occupation and hobbies should be asked. The purpose of this review is to introduce to our collaques up dated allergic contact dermatitis literatures both in Turkey and in the World.

  5. Electric contact arcing

    International Nuclear Information System (INIS)

    Cuthrell, R.E.

    1976-01-01

    Electrical contacts must function properly in many types of components used in nuclear weapon systems. Design, application, and testing of these components require detailed knowledge of chemical and physical phenomena associated with stockpile storage, stockpile testing, and operation. In the past, investigation of these phenomena has led to significant discoveries on the effects of surface contaminants, friction and wear, and the mechanics of closure on contact performance. A recent investigation of contact arcing phenomena which revealed that, preceding contact closure, arcs may occur at voltages lower than had been previously known is described. This discovery is important, since arcing may damage contacts, and repetitive testing of contacts performed as part of a quality assurance program might produce cumulative damage that would yield misleading life-test data and could prevent proper operation of the contacts at some time in the future. This damage can be avoided by determining the conditions under which arcing occurs, and ensuring that these conditions are avoided in contact testing

  6. [Sport injuries in full contact and semi-contact karate].

    Science.gov (United States)

    Greier, K; Riechelmann, H; Ziemska, J

    2014-03-01

    Karate enjoys great popularity both in professional and recreational sports and can be classified into full, half and low contact styles. The aim of this study was the analysis of sports injuries in Kyokushinkai (full contact) and traditional Karate (semi-contact). In a retrospective study design, 215 active amateur karateka (114 full contact, 101 semi-contact) were interviewed by means of a standardised questionnaire regarding typical sport injuries during the last 36 months. Injuries were categorised into severity grade I (not requiring medical treatment), grade II (single medical treatment), grade III (several outpatient medical treatments) and grade IV (requiring hospitalisation). In total, 217 injuries were reported in detail. 125 injuries (58%) occurred in full contact and 92 (42%) in semi-contact karate. The time related injury rate of full contact karateka was 1.9/1000 h compared to 1.3/1000 h of semi-contact karateka (p injuries were musculoskeletal contusions (33% full contact, 20% semi-contact), followed by articular sprains with 19% and 16%. The lower extremity was affected twice as often in full contact (40%) as in semi-contact (20%) karate. Training injuries were reported by 80% of the full contact and 77% of the semi-contact karateka. Most injuries, both in training and competition, occurred in kumite. 75% of the reported injuries of full contact and 70% of semi-contact karateka were classified as low grade (I or II). The high rate of injuries during training and kumite (sparring) points to specific prevention goals. The emphasis should be put on proprioceptive training and consistent warm-up. In the actual competition the referees play a vital role regarding prevention. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Interactions between human mesenchymal stem cells and natural killer cells.

    Science.gov (United States)

    Sotiropoulou, Panagiota A; Perez, Sonia A; Gritzapis, Angelos D; Baxevanis, Constantin N; Papamichail, Michael

    2006-01-01

    Mesenchymal stem cells (MSCs) are multipotent progenitor cells representing an attractive therapeutic tool for regenerative medicine. They possess unique immunomodulatory properties, being capable of suppressing T-cell responses and modifying dendritic cell differentiation, maturation, and function, whereas they are not inherently immunogenic, failing to induce alloreactivity to T cells and freshly isolated natural killer (NK) cells. To clarify the generation of host immune responses to implanted MSCs in tissue engineering and their potential use as immunosuppressive elements, the effect of MSCs on NK cells was investigated. We demonstrate that at low NK-to-MSC ratios, MSCs alter the phenotype of NK cells and suppress proliferation, cytokine secretion, and cyto-toxicity against HLA-class I- expressing targets. Some of these effects require cell-to-cell contact, whereas others are mediated by soluble factors, including transforming growth factor-beta1 and prostaglandin E2, suggesting the existence of diverse mechanisms for MSC-mediated NK-cell suppression. On the other hand, MSCs are susceptible to lysis by activated NK cells. Overall, these data improve our knowledge of interactions between MSCs and NK cells and consequently of their effect on innate immune responses and their contribution to the regulation of adaptive immunity, graft rejection, and cancer immunotherapy.

  8. LANL Contacts

    Science.gov (United States)

    : (505) 665-3664 ethics@lanl.gov Journalist queries Communications Office (505) 667-7000 Media contacts programs and employee resources. General Employee directory Emergency communication Communications Office (505) 667-7000 Ethics & Audits Internal Audit: (505) 665-3104 Ethics Office: (505) 667-7506 Fax

  9. Mesenchymal Stem Cells

    DEFF Research Database (Denmark)

    Horwood, Nicole J.; Dazzi, Francesco; Zaher, Walid

    2012-01-01

    Mesenchymal stem cells (MSC) are stem cell populations present among the bone marrow stroma and a number of other tissues that are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. MSC provide supportive stroma for growth...... and differentiation of hematopoietic stem cells (HSC) and hematopoiesis. These cells have been described as important immunoregulators due to their ability to suppress T cells proliferation. MSC can also directly contribute to tissue repair by migrating to sites of injury and providing a source of cells...... for differentiation and/or providing bystander support for resident stromal cells. This chapter discusses the cellular and molecular properties of MSC, the mechanisms by which they can modulate immune responses and the clinical applications of MSC in disorders such as graft-versus-host disease and aplastic anaemia...

  10. [Gastric mesenchymal tumours (GIST)].

    Science.gov (United States)

    Spivach, Arrigo; Fezzi, Margherita; Sartori, Alberto; Belgrano, Manuel; Rimondini, Alessandra; Cuttin-Zernich, Roberto; Covab, Maria Assunta; Bonifacio, Daniela; Buri, Luigi; Pagani, Carlo; Zanconati, Fabrizio

    2008-01-01

    The incidence of gastrointestinal stromal tumours (GIST) has increased in recent years. A number of authors have attempted to define the actual nature of these tumours. Immunohistochemistry highlighting the positivity of tyrosine-kinase (CD117/c-Kit) has revealed the difference between gastrointestinal stromal tumours and other mesenchymal tumours and, therefore, the possibility of medical rather than surgical therapy. We retrospectively reviewed 19 patients affected by primary gastric GIST, who underwent surgery in recent years with subsequent follow-up. Gastroscopy and gastrointestinal tract radiography were used not only to obtain the diagnosis but also to establish the size, density, contours, ulceration, regional lymphadenopathy, mesenteric infiltration and the presence of metastases. The aim of this study was to evaluate the roles of endoscopy and radiology in this pathology and the advantages and limitations of each individual technique.

  11. Recruiting former melanoma patients via hospitals in comparison to office-based dermatologists in a register-based cohort study that required indirect contact

    Directory of Open Access Journals (Sweden)

    S. R. Zeissig

    2017-11-01

    Full Text Available Abstract Background There are detailed reviews about different recruitment strategies, but not with regard to differences between recruitment of hospital-based versus office-based physicians. Within this study, the two different recruitment schemes are compared. Advantages and disadvantages of different ways of recruitment in registry-based studies are discussed. Methods In a cross-sectional cancer-registry-based study, long-term melanoma patients were contacted by dermatologists rather than directly by the registry on the basis of the legal situation. Logistic regression models and generalized estimating equations were used to assess effects of various patient and physician characteristics on participation and data quality. Especially differences between hospital-based versus office-based dermatologists are evaluated. Results Seventy two out of 112 contacted dermatologists took part in the study (64.3%. The cooperation proportion was 52.2% (689 participants/1320 contacted patients. Participants and non-participants differed regarding age and sex, but not regarding other social demographic factors and cancer stage. We did not observe a difference in patient participation between hospital-based versus office-based dermatologists (OR 1.08 [CI 0.84–1.39]; p = 0.57. However, medical data provided by the cancer registry were better for participants registered and recruited by hospitals. Conclusions In cohort studies with epidemiological cancer registries, recruitment via physicians has potential disadvantages and is more complex. If this indirect way of contact is mandatory, we recommend recruitment procedures including hospital-based rather than office-based physicians. However, physician characteristics were not associated with outcome.

  12. Fermilab Education Office - Contacts

    Science.gov (United States)

    Search The Office of Education and Public Outreach: Contacts All telephone numbers require area code Presentations for Presenters 840-3094 Office of Education and Public Outreach Spencer Pasero spasero@fnal.gov Education Office 840-3076 Fermilab Friends for Science Education General Questions Susan Dahl sdahl@fnal.gov

  13. Brain mesenchymal stem cells: physiology and pathological implications.

    Science.gov (United States)

    Pombero, Ana; Garcia-Lopez, Raquel; Martinez, Salvador

    2016-06-01

    Mesenchymal stem cells (MSCs) are defined as progenitor cells that give rise to a number of unique, differentiated mesenchymal cell types. This concept has progressively evolved towards an all-encompassing concept including multipotent perivascular cells of almost any tissue. In central nervous system, pericytes are involved in blood-brain barrier, and angiogenesis and vascular tone regulation. They form the neurovascular unit (NVU) together with endothelial cells, astrocytes and neurons. This functional structure provides an optimal microenvironment for neural proliferation in the adult brain. Neurovascular niche include both diffusible signals and direct contact with endothelial and pericytes, which are a source of diffusible neurotrophic signals that affect neural precursors. Therefore, MSCs/pericyte properties such as differentiation capability, as well as immunoregulatory and paracrine effects make them a potential resource in regenerative medicine. © 2016 Japanese Society of Developmental Biologists.

  14. Prioritized Contact Transport Stream

    Science.gov (United States)

    Hunt, Walter Lee, Jr. (Inventor)

    2015-01-01

    A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

  15. Rough Surface Contact

    Directory of Open Access Journals (Sweden)

    T Nguyen

    2017-06-01

    Full Text Available This paper studies the contact of general rough curved surfaces having nearly identical geometries, assuming the contact at each differential area obeys the model proposed by Greenwood and Williamson. In order to account for the most general gross geometry, principles of differential geometry of surface are applied. This method while requires more rigorous mathematical manipulations, the fact that it preserves the original surface geometries thus makes the modeling procedure much more intuitive. For subsequent use, differential geometry of axis-symmetric surface is considered instead of general surface (although this “general case” can be done as well in Chapter 3.1. The final formulas for contact area, load, and frictional torque are derived in Chapter 3.2.

  16. Contact dermatitis

    Science.gov (United States)

    ... may need to change your job or job habits if the disorder is caused by exposure at work. For example, jobs requiring frequent hand washing may be bad choices for people with hand dermatitis. Sometimes, the ...

  17. Reducing contact resistance in graphene devices through contact area patterning.

    Science.gov (United States)

    Smith, Joshua T; Franklin, Aaron D; Farmer, Damon B; Dimitrakopoulos, Christos D

    2013-04-23

    Performance of graphene electronics is limited by contact resistance associated with the metal-graphene (M-G) interface, where unique transport challenges arise as carriers are injected from a 3D metal into a 2D-graphene sheet. In this work, enhanced carrier injection is experimentally achieved in graphene devices by forming cuts in the graphene within the contact regions. These cuts are oriented normal to the channel and facilitate bonding between the contact metal and carbon atoms at the graphene cut edges, reproducibly maximizing "edge-contacted" injection. Despite the reduction in M-G contact area caused by these cuts, we find that a 32% reduction in contact resistance results in Cu-contacted, two-terminal devices, while a 22% reduction is achieved for top-gated graphene transistors with Pd contacts as compared to conventionally fabricated devices. The crucial role of contact annealing to facilitate this improvement is also elucidated. This simple approach provides a reliable and reproducible means of lowering contact resistance in graphene devices to bolster performance. Importantly, this enhancement requires no additional processing steps.

  18. Controlling laser-induced jet formation for bioprinting mesenchymal stem cells with high viability and high resolution

    International Nuclear Information System (INIS)

    Ali, Muhammad; Pages, Emeline; Ducom, Alexandre; Fontaine, Aurelien; Guillemot, Fabien

    2014-01-01

    Laser-assisted bioprinting is a versatile, non-contact, nozzle-free printing technique which has demonstrated high potential for cell printing with high resolution. Improving cell viability requires determining printing conditions which minimize shear stress for cells within the jet and cell impact at droplet landing. In this context, this study deals with laser-induced jet dynamics to determine conditions from which jets arise with minimum kinetic energies. The transition from a sub-threshold regime to jetting regime has been associated with a geometrical parameter (vertex angle) which can be harnessed to print mesenchymal stem cells with high viability using slow jet conditions. Finally, hydrodynamic jet stability is also studied for higher laser pulse energies which give rise to supersonic but turbulent jets. (paper)

  19. Feasibility of mesenchymal stem cell culture expansion for a phase I clinical trial in multiple sclerosis.

    Science.gov (United States)

    Planchon, Sarah M; Lingas, Karen T; Reese Koç, Jane; Hooper, Brittney M; Maitra, Basabi; Fox, Robert M; Imrey, Peter B; Drake, Kylie M; Aldred, Micheala A; Lazarus, Hillard M; Cohen, Jeffrey A

    2018-01-01

    Multiple sclerosis is an inflammatory, neurodegenerative disease of the central nervous system for which therapeutic mesenchymal stem cell transplantation is under study. Published experience of culture-expanding multiple sclerosis patients' mesenchymal stem cells for clinical trials is limited. To determine the feasibility of culture-expanding multiple sclerosis patients' mesenchymal stem cells for clinical use. In a phase I trial, autologous, bone marrow-derived mesenchymal stem cells were isolated from 25 trial participants with multiple sclerosis and eight matched controls, and culture-expanded to a target single dose of 1-2 × 10 6 cells/kg. Viability, cell product identity and sterility were assessed prior to infusion. Cytogenetic stability was assessed by single nucleotide polymorphism analysis of mesenchymal stem cells from 18 multiple sclerosis patients and five controls. One patient failed screening. Mesenchymal stem cell culture expansion was successful for 24 of 25 multiple sclerosis patients and six of eight controls. The target dose was achieved in 16-62 days, requiring two to three cell passages. Growth rate and culture success did not correlate with demographic or multiple sclerosis disease characteristics. Cytogenetic studies identified changes on one chromosome of one control (4.3%) after extended time in culture. Culture expansion of mesenchymal stem cells from multiple sclerosis patients as donors is feasible. However, culture time should be minimized for cell products designated for therapeutic administration.

  20. PDGF controls contact inhibition of locomotion by regulating N-cadherin during neural crest migration.

    Science.gov (United States)

    Bahm, Isabel; Barriga, Elias H; Frolov, Antonina; Theveneau, Eric; Frankel, Paul; Mayor, Roberto

    2017-07-01

    A fundamental property of neural crest (NC) migration is contact inhibition of locomotion (CIL), a process by which cells change their direction of migration upon cell contact. CIL has been proven to be essential for NC migration in amphibians and zebrafish by controlling cell polarity in a cell contact-dependent manner. Cell contact during CIL requires the participation of the cell adhesion molecule N-cadherin, which starts to be expressed by NC cells as a consequence of the switch between E- and N-cadherins during epithelial-to-mesenchymal transition (EMT). However, the mechanism that controls the upregulation of N-cadherin remains unknown. Here, we show that platelet-derived growth factor receptor alpha (PDGFRα) and its ligand platelet-derived growth factor A (PDGF-A) are co-expressed in migrating cranial NC. Inhibition of PDGF-A/PDGFRα blocks NC migration by inhibiting N-cadherin and, consequently, impairing CIL. Moreover, we identify phosphatidylinositol-3-kinase (PI3K)/AKT as a downstream effector of the PDGFRα cellular response during CIL. Our results lead us to propose PDGF-A/PDGFRα signalling as a tissue-autonomous regulator of CIL by controlling N-cadherin upregulation during EMT. Finally, we show that once NC cells have undergone EMT, the same PDGF-A/PDGFRα works as an NC chemoattractant, guiding their directional migration. © 2017. Published by The Company of Biologists Ltd.

  1. Contact Lens Care

    Science.gov (United States)

    ... Consumers Consumer Information by Audience For Women Contact Lens Care Share Tweet Linkedin Pin it More sharing ... www.fda.gov/medwatch Learn More about Contact Lens Care Other Tips on Contact Lenses Decorative Contact ...

  2. Cloning of regions required for contact hemolysis and entry into LLC-MK2 cells from Shigella sonnei form I plasmid: virF is a positive regulator gene for these phenotypes.

    OpenAIRE

    Kato, J; Ito, K; Nakamura, A; Watanabe, H

    1989-01-01

    Two distinct regions required for both contact hemolysis and entry into LLC-MK2 cells were cloned into Escherichia coli from the Shigella sonnei form I plasmid, pSS120. The first region was cloned into an E. coli HB101 strain containing noninvasive Tn1 insertion mutants of the form I plasmid, and expression of ipa (invasion plasmid antigen) gene products was restored. The plasmid carrying the first region was then transformed into E. coli lacking the form I plasmid, and additional DNA fragmen...

  3. Proliferation of Peripheral Blood Lymphocytes and Mesenchymal Stromal Cells Derived from Wharton's Jelly in Mixed and Membrane-Separated Cultures.

    Science.gov (United States)

    Poltavtsev, A M; Poltavtseva, R A; Yushina, M N; Pavlovich, S V; Svirshchevskaya, E V

    2017-08-01

    We studied the effect of mesenchymal stromal cells on proliferation of CFSE-stained T cells in mixed and membrane-separated (Transwell) cultures and in 3D culture of mesenchymal stromal cells from Wharton's jelly. The interaction of mesenchymal stromal cells with mitogen-activated peripheral blood lymphocytes from an allogeneic donor was followed by suppression of T-cell proliferation in a wide range of cell proportions. Culturing in the Transwell system showed the absence of suppression assessed by the fraction of proliferating cells and by the cell cycle analysis. In 3D cultures, contact interaction of mesenchymal stromal cells and lymphocytes was demonstrated that led to accumulation of G2/M phase lymphocytes and G0/G1 phase mesenchymal stromal cells. The suppressive effect of mesenchymal stromal cells from Wharton's jelly is mediated by two mechanisms. The effects are realized within 6 days, which suggests that the therapeutic effects of mesenchymal stromal cells persist until their complete elimination from the body.

  4. A Molecular Staple: D-Loops in the I Domain of Bacteriophage P22 Coat Protein Make Important Intercapsomer Contacts Required for Procapsid Assembly

    Science.gov (United States)

    D'Lima, Nadia G.

    2015-01-01

    ABSTRACT Bacteriophage P22, a double-stranded DNA (dsDNA) virus, has a nonconserved 124-amino-acid accessory domain inserted into its coat protein, which has the canonical HK97 protein fold. This I domain is involved in virus capsid size determination and stability, as well as protein folding. The nuclear magnetic resonance (NMR) solution structure of the I domain revealed the presence of a D-loop, which was hypothesized to make important intersubunit contacts between coat proteins in adjacent capsomers. Here we show that amino acid substitutions of residues near the tip of the D-loop result in aberrant assembly products, including tubes and broken particles, highlighting the significance of the D-loops in proper procapsid assembly. Using disulfide cross-linking, we showed that the tips of the D-loops are positioned directly across from each other both in the procapsid and the mature virion, suggesting their importance in both states. Our results indicate that D-loop interactions act as “molecular staples” at the icosahedral 2-fold symmetry axis and significantly contribute to stabilizing the P22 capsid for DNA packaging. IMPORTANCE Many dsDNA viruses have morphogenic pathways utilizing an intermediate capsid, known as a procapsid. These procapsids are assembled from a coat protein having the HK97 fold in a reaction driven by scaffolding proteins or delta domains. Maturation of the capsid occurs during DNA packaging. Bacteriophage HK97 uniquely stabilizes its capsid during maturation by intercapsomer cross-linking, but most virus capsids are stabilized by alternate means. Here we show that the I domain that is inserted into the coat protein of bacteriophage P22 is important in the process of proper procapsid assembly. Specifically, the I domain allows for stabilizing interactions across the capsid 2-fold axis of symmetry via a D-loop. When amino acid residues at the tip of the D-loop are mutated, aberrant assembly products, including tubes, are formed instead

  5. The disruption of the epithelial mesenchymal trophic unit in COPD.

    Science.gov (United States)

    Behzad, Ali R; McDonough, John E; Seyednejad, Nazgol; Hogg, James C; Walker, David C

    2009-12-01

    Progression of COPD is associated with a measurable increase in small airway wall thickness resulting from a repair and remodeling process that involves fibroblasts of the epithelial mesenchymal trophic unit (EMTU). The present study was designed to examine the organization of fibroblasts within the lamina propria of small airways with respect to their contacts with the epithelium and with each other in persons with COPD. Transmission electron microcopy (TEM) and three-dimensional (3D) reconstructions of serial TEM sections were used to estimate the frequency and determine the nature of the contacts between the epithelium and fibroblasts within the EMTU in small airways from 5 controls (smokers with normal lung function), from 6 persons with mild (GOLD-1) and 5 with moderate (GOLD-2) COPD. In airways from control lungs fibroblasts make frequent contact with cytoplasmic extensions of epithelial cells through apertures in the epithelial basal lamina, but the frequency of these fibroblast-epithelial contacts is reduced in both mild and moderate COPD compared to controls (p < 0.01). The 3D reconstructions showed that the cytoplasmic extensions of lamina propria fibroblasts form a reticulum with fibroblast-fibroblast contacts in an airway from a control subject but this reticulum may be reorganized in airways of COPD patients. Development of COPD is associated with significant disruption of the EMTU due to a reduction of contacts between fibroblasts and the epithelium.

  6. Enhanced human bone marrow mesenchymal stem cell functions on cathodic arc plasma-treated titanium

    Directory of Open Access Journals (Sweden)

    Zhu W

    2015-12-01

    Full Text Available Wei Zhu,1 George Teel,1 Christopher M O’Brien,1 Taisen Zhuang,1 Michael Keidar,1 Lijie Grace Zhang1–3 1Department of Mechanical and Aerospace Engineering, 2Department of Biomedical Engineering, 3Department of Medicine, The George Washington University, Washington, DC, USA Abstract: Surface modification of titanium for use in orthopedics has been explored for years; however, an ideal method of integrating titanium with native bone is still required to this day. Since human bone cells directly interact with nanostructured extracellular matrices, one of the most promising methods of improving titanium’s osseointegration involves inducing biomimetic nanotopography to enhance cell–implant interaction. In this regard, we explored an approach to functionalize the surface of titanium by depositing a thin film of textured titanium nanoparticles via a cathodic arc discharge plasma. The aim is to improve human bone marrow mesenchymal stem cell (MSC attachment and differentiation and to reduce deleterious effects of more complex surface modification methods. Surface functionalization was analyzed by scanning electron microscopy, atomic force microscopy, contact angle testing, and specific protein adsorption. Scanning electron microscopy and atomic force microscopy examination demonstrate the deposition of titanium nanoparticles and the surface roughness change after coating. The specific fibronectin adsorption was enhanced on the modified titanium surface that associates with the improved hydrophilicity. MSC adhesion and proliferation were significantly promoted on the nanocoated surface. More importantly, compared to bare titanium, greater production of total protein, deposition of calcium mineral, and synthesis of alkaline phosphatase were observed from MSCs on nanocoated titanium after 21 days. The method described herein presents a promising alternative method for inducing more cell favorable nanosurface for improved orthopedic applications

  7. Mesenchymal progenitor cells for the osteogenic lineage.

    Science.gov (United States)

    Ono, Noriaki; Kronenberg, Henry M

    2015-09-01

    Mesenchymal progenitors of the osteogenic lineage provide the flexibility for bone to grow, maintain its function and homeostasis. Traditionally, colony-forming-unit fibroblasts (CFU-Fs) have been regarded as surrogates for mesenchymal progenitors; however, this definition cannot address the function of these progenitors in their native setting. Transgenic murine models including lineage-tracing technologies based on the cre-lox system have proven to be useful in delineating mesenchymal progenitors in their native environment. Although heterogeneity of cell populations of interest marked by a promoter-based approach complicates overall interpretation, an emerging complexity of mesenchymal progenitors has been revealed. Current literatures suggest two distinct types of bone progenitor cells; growth-associated mesenchymal progenitors contribute to explosive growth of bone in early life, whereas bone marrow mesenchymal progenitors contribute to the much slower remodeling process and response to injury that occurs mainly in adulthood. More detailed relationships of these progenitors need to be studied through further experimentation.

  8. EGF does not induce Msx-1 and Msx-2 in dental mesenchyme.

    Science.gov (United States)

    Wang, Y H; Kollar, E J; Upholt, W B; Mina, M

    1998-01-01

    Previous heterospecific tissue recombinations indicate that mandibular epithelium exerts the first known inductive signal for odontogenesis in mouse embryos. BMP-4 and EGF are two growth factors implicated as signaling molecules mediating the initial inductive epithelial-mesenchymal interactions during odontogenesis. The purpose of the present study was to examine and compare the effects of these growth factors and mouse mandibular epithelium on expression of Msx-1 and Msx-2 genes in molar-forming mesenchyme. Agarose beads soaked in growth factors or pieces of mouse mandibular epithelium (E11) were placed in contact with E11 molar-forming mesenchyme and cultured for 24 h. Whole-mount in situ hybridization analysis revealed that, in contrast to mouse mandibular epithelium and BMP-4-releasing beads, EGF-releasing beads did not induce the expression of Msx-1 and Msx-2 in E11 molar-forming mesenchyme. These observations suggest that whereas BMP-4 may be involved in activation of Msx-1 and Msx-2 in the underlying mesenchyme, EGF may regulate events involved in the formation of dental lamina.

  9. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... Costume Contact Lenses Can Ruin Vision Eye Makeup Safety In fact, it is illegal to sell colored ...

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ...

  11. Occupational protein contact dermatitis.

    Science.gov (United States)

    Barbaud, Annick; Poreaux, Claire; Penven, Emmanuelle; Waton, Julie

    2015-01-01

    Occupational contact dermatitis is generally caused by haptens but can also be induced by proteins causing mainly immunological contact urticaria (ICU); chronic hand eczema in the context of protein contact dermatitis (PCD). In a monocentric retrospective study, from our database, only 31 (0.41%) of patients with contact dermatitis had positive skin tests with proteins: 22 had occupational PCD, 3 had non-occupational PCD, 5 occupational ICU and 1 cook had a neutrophilic fixed food eruption (NFFE) due to fish. From these results and analysis of literature, the characteristics of PCD can be summarized as follows. It is a chronic eczematous dermatitis, possibly exacerbated by work, suggestive if associated with inflammatory perionyxix and immediate erythema with pruritis, to be investigated when the patient resumes work after a period of interruption. Prick tests with the suspected protein-containing material are essential, as patch tests have negative results. In case of multisensitisation revealed by prick tests, it is advisable to analyse IgE against recombinant allergens. A history of atopy, found in 56 to 68% of the patients, has to be checked for. Most of the cases are observed among food-handlers but PCD can also be due to non-edible plants, latex, hydrolysed proteins or animal proteins. Occupational exposure to proteins can thus lead to the development of ICU. Reflecting hypersensitivity to very low concentrations of allergens, investigating ICU therefore requires caution and prick tests should be performed with a diluted form of the causative protein-containing product. Causes are food, especially fruit peel, non-edible plants, cosmetic products, latex, animals.

  12. Adipose-derived mesenchymal stem cells and regenerative medicine.

    Science.gov (United States)

    Konno, Masamitsu; Hamabe, Atsushi; Hasegawa, Shinichiro; Ogawa, Hisataka; Fukusumi, Takahito; Nishikawa, Shimpei; Ohta, Katsuya; Kano, Yoshihiro; Ozaki, Miyuki; Noguchi, Yuko; Sakai, Daisuke; Kudoh, Toshihiro; Kawamoto, Koichi; Eguchi, Hidetoshi; Satoh, Taroh; Tanemura, Masahiro; Nagano, Hiroaki; Doki, Yuichiro; Mori, Masaki; Ishii, Hideshi

    2013-04-01

    Adipose tissue-derived mesenchymal stem cells (ADSCs) are multipotent and can differentiate into various cell types, including osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β-cells, and hepatocytes. Compared with the extraction of other stem cells such as bone marrow-derived mesenchymal stem cells (BMSCs), that of ADSCs requires minimally invasive techniques. In the field of regenerative medicine, the use of autologous cells is preferable to embryonic stem cells or induced pluripotent stem cells. Therefore, ADSCs are a useful resource for drug screening and regenerative medicine. Here we present the methods and mechanisms underlying the induction of multilineage cells from ADSCs. © 2013 The Authors Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.

  13. Human stromal (mesenchymal) stem cells

    DEFF Research Database (Denmark)

    Aldahmash, Abdullah; Zaher, Walid; Al-Nbaheen, May

    2012-01-01

    Human stromal (mesenchymal) stem cells (hMSC) represent a group of non-hematopoietic stem cells present in the bone marrow stroma and the stroma of other organs including subcutaneous adipose tissue, placenta, and muscles. They exhibit the characteristics of somatic stem cells of self......-renewal and multi-lineage differentiation into mesoderm-type of cells, e.g., to osteoblasts, adipocytes, chondrocytes and possibly other cell types including hepatocytes and astrocytes. Due to their ease of culture and multipotentiality, hMSC are increasingly employed as a source for cells suitable for a number...

  14. Nordic project food contact materials

    DEFF Research Database (Denmark)

    Li, Ågot; Tesdal Håland, Julie; Petersen, Jens Højslev

    Denmark, Finland, Faroe Islands, Iceland, Norway and Sweden have in 2013––2015 conducted a Nordic project on food contact materials. Food contact materials are used in all stages of food production and can be a general source of contamination. The food safety authorities in most of the Nordic...... countries have had a limited focus on the FCM area with the exception of Denmark and Finland. The aim of the project was therefore to control establishments producing, importing or using plastic food contact materials as well as to increase the knowledge of the inspectors performing these controls....... The focus of the inspections was to control the declaration of compliance (DoC) for plastic food contact materials. The requirement for a Doc is mandatory in order to ensure that the FCM complies with the legislation. In addition some products were analyzed for phthalates....

  15. Contact Dermatitis in Pediatrics.

    Science.gov (United States)

    Pelletier, Janice L; Perez, Caroline; Jacob, Sharon E

    2016-08-01

    Contact dermatitis is an umbrella term that describes the skin's reaction to contacted noxious or allergenic substances. The two main categories of contact dermatitis are irritant type and allergic type. This review discusses the signs, symptoms, causes, and complications of contact dermatitis. It addresses the testing, treatment, and prevention of contact dermatitis. Proper management of contact dermatitis includes avoidance measures for susceptible children. Implementation of a nickel directive (regulating the use of nickel in jewelry and other products that come into contact with the skin) could further reduce exposure to the most common allergens in the pediatric population. [Pediatr Ann. 2016;45(8):e287-e292.]. Copyright 2016, SLACK Incorporated.

  16. Central nervous system mesenchymal chondrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Salvati, M.; Frati, A.; Piccirilli, M.; Agrillo, A.; Brogna, C.; Occhiogrosso, G.; Giangaspero, F. [INM Neuromed IRCCS, Pozzilli (Italy). Dept. of Neurosurgery; Caroli, E. [Policlinico S. Andrea, Rome (Italy). Dept. of Neurological Sciences, Neurosurgery

    2005-06-15

    Central nervous system mesenchymal chondrosarcomas are rare malignant tumors that constitute a separate entity from the classical chondrosarcoma and myxoid variant. Clinical behaviour of central nervous system chondrosarcomas is still unknown. We describe two rare examples of intracranial mesenchymal chondrosarcoma with a review of the literature, in an attempt to clarify the clinical characteristics, prognosis and treatment of choice of these unusual tumors. Among the 55 reported cases, 23 had postoperative radiotherapy. Although there is no statistical significance according to the Log-Rank test (p=0.7), the patients treated with radiation therapy seem to have a better chance of survival. Patients who had adjuvant chemotherapy (only 5) showed survival times similar to those patients who had none. Although clinical behaviour of central nervous system chondrosarcomas remains to be defined, data from our series as well as literature show that radical removal is the best therapeutic choice. In addition, patients treated with postoperative radiotherapy seem to show a trend toward increased survival.

  17. Central nervous system mesenchymal chondrosarcoma

    International Nuclear Information System (INIS)

    Salvati, M.; Frati, A.; Piccirilli, M.; Agrillo, A.; Brogna, C.; Occhiogrosso, G.; Giangaspero, F.; Caroli, E.

    2005-01-01

    Central nervous system mesenchymal chondrosarcomas are rare malignant tumors that constitute a separate entity from the classical chondrosarcoma and myxoid variant. Clinical behaviour of central nervous system chondrosarcomas is still unknown. We describe two rare examples of intracranial mesenchymal chondrosarcoma with a review of the literature, in an attempt to clarify the clinical characteristics, prognosis and treatment of choice of these unusual tumors. Among the 55 reported cases, 23 had postoperative radiotherapy. Although there is no statistical significance according to the Log-Rank test (p=0.7), the patients treated with radiation therapy seem to have a better chance of survival. Patients who had adjuvant chemotherapy (only 5) showed survival times similar to those patients who had none. Although clinical behaviour of central nervous system chondrosarcomas remains to be defined, data from our series as well as literature show that radical removal is the best therapeutic choice. In addition, patients treated with postoperative radiotherapy seem to show a trend toward increased survival

  18. The influence of scaffold microstructure on chondrogenic differentiation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Zhang, Jingjing; Ge, Zigang; Wu, Yingnan; Lee, Eng Hin; Thote, Tanushree; Yang, Zheng

    2014-01-01

    Different forms of biomaterials, including microspheres, sponges, hydrogels and nanofibres have been broadly used in cartilage regeneration; however, effects of internal structures of biomaterials on chondrogenesis of mesenchymal stem cells (MSCs) remain largely unexplored. Here we investigated the effect of physical microenvironments of sponges and hydrogels on chondrogenic differentiation of MSCs. MSCs, cultured in these two scaffold systems, were induced with TGF-β 3  in chondrogeneic differentiation medium and the chondrogenic differentiation was evaluated and compared after three weeks. MSCs in the sponges clustered with spindle morphologies, while they distributed homogenously with round morphologies in the hydrogel. The MSCs proliferated faster in the sponge compared to that in the hydrogel. Significantly higher glycosaminoglycan and collagen II were found in the sponges but not in the hydrogels. The different tissue formation ability of MSCs in these two systems could be attributed to the different metabolic requirements and the cellular events prerequisite in the chondrogenic process of MSCs. It is reasonable to conclude that sponges with relatively active microenvironments that facilitate cell–cell contacts and cell–matrix interaction are optimal for early stage of chondrogeneic differentiation. (paper)

  19. Biocompatibility and favorable response of mesenchymal stem cells on fibronectin-gold nanocomposites.

    Directory of Open Access Journals (Sweden)

    Huey-Shan Hung

    Full Text Available A simple surface modification method, comprising of a thin coating with gold nanoparticles (AuNPs and fibronectin (FN, was developed to improve the biocompatibility required for cardiovascular devices. The nanocomposites from FN and AuNPs (FN-Au were characterized by the atomic force microscopy (AFM, UV-Vis spectrophotometry (UV-Vis, and Fourier transform infrared spectroscopy (FTIR. The biocompatibility of the nanocomposites was evaluated by the response of monocytes and platelets to the material surface in vitro. FN-Au coated surfaces demonstrated low monocyte activation and platelet activation. The behavior of human umbilical cord-derived mesenchymal stem cells (MSCs on FN-Au was further investigated. MSCs on FN-Au nanocomposites particularly that containing 43.5 ppm of AuNPs (FN-Au 43.5 ppm showed cell proliferation, low ROS generation, as well as increases in the protein expression levels of matrix metalloproteinase-9 (MMP-9 and endothelial nitric oxide synthase (eNOS, which may account for the enhanced MSC migration on the nanocomposites. These results suggest that the FN-Au nanocomposite thin film coating may serve as a potential and simple solution for the surface modification of blood-contacting devices such as vascular grafts.

  20. Contact mechanics: contact area and interfacial separation from small contact to full contact

    International Nuclear Information System (INIS)

    Yang, C; Persson, B N J

    2008-01-01

    We present a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. The numerical calculations mainly focus on the contact area and the interfacial separation from small contact (low load) to full contact (high load). For a small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load. For a high load the contact area approaches the nominal contact area (i.e. complete contact), and the interfacial separation approaches zero. The numerical results have been compared with analytical theory and experimental results. They are in good agreement with each other. The present findings may be very important for soft solids, e.g. rubber, or for very smooth surfaces, where complete contact can be reached at moderately high loads without plastic deformation of the solids

  1. Epithelial-to-mesenchymal transition in the development of endometriosis.

    Science.gov (United States)

    Yang, Yan-Meng; Yang, Wan-Xi

    2017-06-20

    Endometriosis, an estrogen-dependent chronic gynecological disease, is common in reproductive-age women and profoundly affects their life quality. Although various pathogenic theories have been proposed, the origin of endometriosis remains unclear. Epithelial to mesenchymal transition (EMT) is a process that epithelial cells lose polarized organization of the cytoskeleton and cell-to-cell contacts, acquiring the high motility of mesenchymal cells. These changes are thought to be prerequisites for the original establishment of endometriotic lesions. However, no study exactly indicates which type of EMT occurs in endometriosis. In this review, we conclude that two different types of EMT may participate in this disease. Besides, two stimulating signals, hypoxia and estrogen, can through different pathways to activate the EMT process in endometriosis. Those pathways involve many cellular factors such as TGF-beta and Wnt, ultimately leading to cell proliferation and migration. As infertility is becoming a serious and intractable issue for women, EMT, during the implantation process, is gaining attention. In this review, we will describe the known functions of EMT in endometriosis, and suggest further studies that may aid in the development of medical therapy.

  2. Insight into the Role of Long Non-coding RNAs During Osteogenesis in Mesenchymal Stem Cells.

    Science.gov (United States)

    Huo, Sibei; Zhou, Yachuan; He, Xinyu; Wan, Mian; Du, Wei; Xu, Xin; Ye, Ling; Zhou, Xuedong; Zheng, Liwei

    2018-01-01

    Long non-coding RNAs (LncRNAs) are non-protein coding transcripts longer than 200 nucleotides in length. Instead of being "transcriptional noise", lncRNAs are emerging as a key modulator in various biological processes and disease development. Mesenchymal stem cells can be isolated from various adult tissues, such as bone marrow and dental tissues. The differentiation processes into multiple lineages, such as osteogenic differentiation, are precisely orchestrated by molecular signals in both genetic and epigenetic ways. Recently, several lines of evidence suggested the role of lncRNAs participating in cell differentiation through the regulation of gene transcriptions. And the involvement of lncRNAs may be associated with initiation and progression of mesenchymal stem cell-related diseases. We aimed at addressing the role of lncRNAs in the regulation of osteogenesis of mesenchymal stem cells derived from bone marrow and dental tissues, and discussing the potential utility of lncRNAs as biomarkers and therapeutic targets for mesenchymal stem cell-related diseases. Numerous lncRNAs were differentially expressed during osteogenesis or odontogenesis of mesenchymal stem cells, and some of them were confirmed to be able to regulate the differentiation processes through the modifications of chromatin, transcriptional and post-transcriptional processes. LncRNAs were also associated with some diseases related with pathologic differentiation of mesenchymal stem cells. LncRNAs involve in the osteogenic differentiation of bone marrow and dental tissuederived mesenchymal stem cells, and they could become promising therapeutic targets and prognosis parameters. However, the mechanisms of the role of lncRNAs are still enigmatic and require further investigation. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Cleveland. "This is far from the truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager ... about the members of the eye-care team . Consumer warning about the improper use of colored contact ...

  4. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... One Use Facts About Colored Contacts and Halloween Safety Colored Contact Lens Facts Over-the-Counter Costume ... new application of artificial intelligence shows whether a patient’s eyes point to high blood pressure or risk ...

  5. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Costume Contacts May Contain Chemicals Harmful to Eyes Four Ways Over-the-Counter Costume Contact Lenses Can ... was in severe pain and on medication for four weeks, and couldn't see well enough to ...

  6. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... sell contacts without a prescription are breaking the law, and may be fined $11,000 per violation. " ... wear any kind of contact lens. In Butler's case, the lenses caused an infection and left her ...

  7. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Hazard: The Hidden Dangers of Buying Decorative Contact Lenses Without a Prescription Leer en Español: Peligros asociados ... truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager Blinded In One Eye By Non- ...

  8. Colored Contact Lens Dangers

    Science.gov (United States)

    ... Hazard: The Hidden Dangers of Buying Decorative Contact Lenses Without a Prescription Leer en Español: Peligros asociados ... truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager Blinded In One Eye By Non- ...

  9. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Cleveland. "This is far from the truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager ... the lenses. Never share contact lenses with another person. Get follow up exams with your eye care ...

  10. Contact Angle Goniometer

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The FTA32 goniometer provides video-based contact angle and surface tension measurement. Contact angles are measured by fitting a mathematical expression...

  11. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... like a suction cup." Halloween is a popular time for people to use colored contact lenses to ... wear costume contact lenses for Halloween or any time of year, follow these guidelines: Get an eye ...

  12. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... glow-in-the-dark lizard lenses, costume contacts can certainly add a spooky, eye-popping touch. But ... consideration as a standard contact lens because they can be purchased over-the-counter or on the ...

  13. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering ... Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at ...

  14. Dermatitis, contact (image)

    Science.gov (United States)

    This picture shows a skin inflammation (dermatitis) caused by contact with a material that causes an allergic reaction in this person. Contact dermatitis is a relatively common condition, and can be caused ...

  15. Contact materials for nanoelectronics

    KAUST Repository

    Alshareef, Husam N.; Quevedo-Ló pez, Manuel Angel Quevedo; Majhi, Prashant

    2011-01-01

    In this article, we review current research activities in contact material development for electronic and nanoelectronic devices. A fundamental issue in contact materials research is to understand and control interfacial reactions and phenomena

  16. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... prescription. Follow the contact lens care directions for cleaning, disinfecting, and wearing the lenses. Never share contact ... with Industry Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American ...

  17. Mesenchymal chondrosarcoma--a case report.

    Directory of Open Access Journals (Sweden)

    Tyagi S

    1992-01-01

    Full Text Available A Case of extraosseous mesenchymal chondrosarcoma occurring in the occipital region in a 26 year old male is being reported. The patient remained free from recurrence on any metastasis even after 2 years of the tumor resection.

  18. Regulation of pulmonary inflammation by mesenchymal cells

    NARCIS (Netherlands)

    Alkhouri, Hatem; Poppinga, Wilfred Jelco; Tania, Navessa Padma; Ammit, Alaina; Schuliga, Michael

    2014-01-01

    Pulmonary inflammation and tissue remodelling are common elements of chronic respiratory diseases such as asthma, chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and pulmonary hypertension (PH). In disease, pulmonary mesenchymal cells not only contribute to tissue

  19. Mesenchymal stem cell therapy for laryngotracheal stenosis

    DEFF Research Database (Denmark)

    Jakobsen, Kathrine Kronberg; Grønhøj, Christian; Jensen, David H

    2017-01-01

    BACKGROUND: Laryngotracheal stenosis (LTS) can be either congenital or acquired. Laryngeal stenosis is most often encountered after prolonged intubation. The mechanism for stenosis following intubation is believed to be hypertrophic scarring. Mesenchymal stem cells (MSCs) therapy has shown...

  20. Contact Lens Risks

    Science.gov (United States)

    ... There is a risk of eye infection from bacteria in swimming pool water, hot tubs, lakes and the ocean Replace your contact lens storage case every 3 months or as directed by your eye care professional. Other Risks of Contact Lenses Other risks of contact lenses include pink eye ( ...

  1. Hydrogenation of passivated contacts

    Energy Technology Data Exchange (ETDEWEB)

    Nemeth, William; Yuan, Hao-Chih; LaSalvia, Vincenzo; Stradins, Pauls; Page, Matthew R.

    2018-03-06

    Methods of hydrogenation of passivated contacts using materials having hydrogen impurities are provided. An example method includes applying, to a passivated contact, a layer of a material, the material containing hydrogen impurities. The method further includes subsequently annealing the material and subsequently removing the material from the passivated contact.

  2. Mixed Lubricated Line Contacts

    NARCIS (Netherlands)

    Faraon, I.C.

    2005-01-01

    The present work deals with friction in mixed lubricated line contacts. Components in systems are becoming smaller and due to, for instance power transmitted, partial contact may occur. In industrial applications, friction between the moving contacting surfaces cannot be avoided, therefore it is

  3. New Cosmetic Contact Allergens

    Directory of Open Access Journals (Sweden)

    An Goossens

    2015-02-01

    Full Text Available Allergic and photo-allergic contact dermatitis, and immunologic contact urticaria are potential immune-mediated adverse effects from cosmetics. Fragrance components and preservatives are certainly the most frequently observed allergens; however, all ingredients must be considered when investigating for contact allergy.

  4. Superstring amplitudes and contact interactions

    International Nuclear Information System (INIS)

    Greensite, J.

    1987-08-01

    We show that scattering amplitudes computed from light-cone superstring field theory are divergent at tree level. The divergences can be eliminated, and supersymmetry restored, by the addition of certain counter terms to the light-cone Hamiltonian. These counter terms have the form of local contact interactions, whose existence we had previously deduced on grounds of vacuum stability, and closure of the super-Poincare algebra. The quartic contact interactions required in Type I and Type IIB superstring theories are constructed in detail. (orig.)

  5. The Disintegrin and Metalloprotease ADAM12 Is Associated with TGF-β-Induced Epithelial to Mesenchymal Transition.

    Directory of Open Access Journals (Sweden)

    Michaël Ruff

    Full Text Available The increased expression of the Disintegrin and Metalloprotease ADAM12 has been associated with human cancers, however its role remain unclear. We have previously reported that ADAM12 expression is induced by the transforming growth factor, TGF-β and promotes TGF-β-dependent signaling through interaction with the type II receptor of TGF-β. Here we explore the implication of ADAM12 in TGF-β-mediated epithelial to mesenchymal transition (EMT, a key process in cancer progression. We show that ADAM12 expression is correlated with EMT markers in human breast cancer cell lines and biopsies. Using a non-malignant breast epithelial cell line (MCF10A, we demonstrate that TGF-β-induced EMT increases expression of the membrane-anchored ADAM12L long form. Importantly, ADAM12L overexpression in MCF10A is sufficient to induce loss of cell-cell contact, reorganization of actin cytoskeleton, up-regulation of EMT markers and chemoresistance. These effects are independent of the proteolytic activity but require the cytoplasmic tail and are specific of ADAM12L since overexpression of ADAM12S failed to induce similar changes. We further demonstrate that ADAM12L-dependent EMT is associated with increased phosphorylation of Smad3, Akt and ERK proteins. Conversely, inhibition of TGF-β receptors or ERK activities reverses ADAM12L-induced mesenchymal phenotype. Together our data demonstrate that ADAM12L is associated with EMT and contributes to TGF-β-dependent EMT by favoring both Smad-dependent and Smad-independent pathways.

  6. Mesenchymal Stem Cells in Tissue Repair

    Directory of Open Access Journals (Sweden)

    Amy M DiMarino

    2013-09-01

    Full Text Available The advent of mesenchymal stem cell (MSC based therapies for clinical therapeutics has been an exciting and new innovation for the treatment of a variety of diseases associated with inflammation, tissue damage and subsequent regeneration and repair. Application-based ability to measure MSC potency and fate of the cells post-MSC therapy are the variables that confound the use of MSCs therapeutics in human diseases. An evaluation of MSC function and applications with attention to detail in the preparation as well as quality control (QC and quality assurance (QA are only as good as the assays that are developed. In vivo measures of efficacy and potency require an appreciation of the overall pathophysiology of the model and standardization of outcome measures. The new concepts of how MSC’s participate in the tissue regeneration and wound repair process and further, how this is impacted by estimates of efficacy and potency Are important new topics. In this regard,,, this chapter will review some of the in vitro and in vivo assays for MSC function and activity and their application to the clinical arena.

  7. LIX1 regulates YAP1 activity and controls the proliferation and differentiation of stomach mesenchymal progenitors.

    Science.gov (United States)

    McKey, Jennifer; Martire, Delphine; de Santa Barbara, Pascal; Faure, Sandrine

    2016-04-28

    Smooth muscle cell (SMC) plasticity maintains the balance between differentiated SMCs and proliferative mesenchymal progenitors, crucial for muscular tissue homeostasis. Studies on the development of mesenchymal progenitors into SMCs have proven useful in identifying molecular mechanisms involved in digestive musculature plasticity in physiological and pathological conditions. Here, we show that Limb Expression 1 (LIX1) molecularly defines the population of mesenchymal progenitors in the developing stomach. Using in vivo functional approaches in the chick embryo, we demonstrate that LIX1 is a key regulator of stomach SMC development. We show that LIX1 is required for stomach SMC determination to regulate the expression of the pro-proliferative gene YAP1 and mesenchymal cell proliferation. However, as stomach development proceeds, sustained LIX1 expression has a negative impact on further SMC differentiation and this is associated with a decrease in YAP1 activity. We demonstrate that expression of LIX1 must be tightly regulated to allow fine-tuning of the transcript levels and state of activation of the pro-proliferative transcriptional coactivator YAP1 to regulate proliferation rates of stomach mesenchymal progenitors and their differentiation. Our data highlight dual roles for LIX1 and YAP1 and provide new insights into the regulation of cell density-dependent proliferation, which is essential for the development and homeostasis of organs.

  8. Antibacterial surface design - Contact kill

    Science.gov (United States)

    Kaur, Rajbir; Liu, Song

    2016-08-01

    Designing antibacterial surfaces has become extremely important to minimize Healthcare Associated Infections which are a major cause of mortality worldwide. A previous biocide-releasing approach is based on leaching of encapsulated biocides such as silver and triclosan which exerts negative impacts on the environment and potentially contributes to the development of bacterial resistance. This drawback of leachable compounds led to the shift of interest towards a more sustainable and environmentally friendly approach: contact-killing surfaces. Biocides that can be bound onto surfaces to give the substrates contact-active antibacterial activity include quaternary ammonium compounds (QACs), quaternary phosphoniums (QPs), carbon nanotubes, antibacterial peptides, and N-chloramines. Among the above, QACs and N-chloramines are the most researched contact-active biocides. We review the engineering of contact-active surfaces using QACs or N-chloramines, the modes of actions as well as the test methods. The charge-density threshold of cationic surfaces for desired antibacterial efficacy and attempts to combine various biocides for the generation of new contact-active surfaces are discussed in detail. Surface positive charge density is identified as a key parameter to define antibacterial efficacy. We expect that this research field will continue to attract more research interest in view of the potential impact of self-disinfective surfaces on healthcare-associated infections, food safety and corrosion/fouling resistance required on industrial surfaces such as oil pipes and ship hulls.

  9. CONTACT RESISTANCE MODELING

    Directory of Open Access Journals (Sweden)

    S. V. LOSKUTOV

    2018-05-01

    Full Text Available Purpose. To determine the contribution of the real contact spots distribution in the total conductivity of the conductors contact. Methodology. The electrical contact resistance research was carried out on models. The experimental part of this work was done on paper with a graphite layer with membranes (the first type and conductive liquids with discrete partitions (the second type. Findings. It is shown that the contact electrical resistance is mainly determined by the real area of metal contact. The experimental dependence of the electrical resistance of the second type model on the distance between the electrodes and the potential distribution along the sample surface for the first type model were obtained. The theoretical model based on the principle of electric field superposition was considered. The dependences obtained experimentally and calculated by using the theoretical model are in good agreement. Originality. The regularity of the electrical contact resistance formation on a large number of membranes was researched for the first time. A new model of discrete electrical contact based on the liquid as the conducting environment with nuclear membrane partitions was developed. The conclusions of the additivity of contact and bulk electrical resistance were done. Practical value. Based on these researches, a new experimental method of kinetic macroidentation that as a parameter of the metal surface layer deformation uses the real contact area was developed. This method allows to determine the value of average contact stresses, yield point, change of the stress on the depth of deformation depending on the surface treatment.

  10. Possible mechanism of disintegrin/like domain in mesenchymal ...

    African Journals Online (AJOL)

    Possible mechanism of disintegrin/like domain in mesenchymal stem cells homing in mice liver injury ... PROMOTING ACCESS TO AFRICAN RESEARCH ... Mesenchymal Stem cells have opened a new approach to deal with liver fibrosis.

  11. Dose-related estrogen effects on gene expression in fetal mouse prostate mesenchymal cells.

    Directory of Open Access Journals (Sweden)

    Julia A Taylor

    Full Text Available Developmental exposure of mouse fetuses to estrogens results in dose-dependent permanent effects on prostate morphology and function. Fetal prostatic mesenchyme cells express estrogen receptor alpha (ERα and androgen receptors and convert stimuli from circulating estrogens and androgens into paracrine signaling to regulate epithelial cell proliferation and differentiation. To obtain mechanistic insight into the role of different doses of estradiol (E2 in regulating mesenchymal cells, we examined E2-induced transcriptomal changes in primary cultures of fetal mouse prostate mesenchymal cells. Urogenital sinus mesenchyme cells were obtained from male mouse fetuses at gestation day 17 and exposed to 10 pM, 100 pM or 100 nM E2 in the presence of a physiological concentration of dihydrotestosterone (0.69 nM for four days. Gene ontology studies suggested that low doses of E2 (10 pM and 100 pM induce genes involved in morphological tissue development and sterol biosynthesis but suppress genes involved in growth factor signaling. Genes involved in cell adhesion were enriched among both up-regulated and down-regulated genes. Genes showing inverted-U-shape dose responses (enhanced by E2 at 10 pM E2 but suppressed at 100 pM were enriched in the glycolytic pathway. At the highest dose (100 nM, E2 induced genes enriched for cell adhesion, steroid hormone signaling and metabolism, cytokines and their receptors, cell-to-cell communication, Wnt signaling, and TGF- β signaling. These results suggest that prostate mesenchymal cells may regulate epithelial cells through direct cell contacts when estrogen level is low whereas secreted growth factors and cytokines might play significant roles when estrogen level is high.

  12. Contact and symplectic topology

    CERN Document Server

    Colin, Vincent; Stipsicz, András

    2014-01-01

    Symplectic and contact geometry naturally emerged from the mathematical description of classical physics. The discovery of new rigidity phenomena and properties satisfied by these geometric structures launched a new research field worldwide. The intense activity of many European research groups in this field is reflected by the ESF Research Networking Programme "Contact And Symplectic Topology" (CAST). The lectures of the Summer School in Nantes (June 2011) and of the CAST Summer School in Budapest (July 2012) provide a nice panorama of many aspects of the present status of contact and symplectic topology. The notes of the minicourses offer a gentle introduction to topics which have developed in an amazing speed in the recent past. These topics include 3-dimensional and higher dimensional contact topology, Fukaya categories, asymptotically holomorphic methods in contact topology, bordered Floer homology, embedded contact homology, and flexibility results for Stein manifolds.

  13. ERK2 protein regulates the proliferation of human mesenchymal stem cells without affecting their mobilization and differentiation potential

    International Nuclear Information System (INIS)

    Carcamo-Orive, Ivan; Tejados, Naiara; Delgado, Jesus; Gaztelumendi, Ainhoa; Otaegui, David; Lang, Valerie; Trigueros, Cesar

    2008-01-01

    Human Mesenchymal Stem Cells (hMSC), derived mainly from adult bone marrow, are valuable models for the study of processes involved in stem cell self-renewal and differentiation. As the Extracellular signal-Regulated Kinase (ERK) signalling pathway is a major contributor to cellular growth, differentiation and survival, we have studied the functions of this kinase in hMSC activity. Ablation of ERK2 gene expression (but not ERK1) by RNA interference significantly reduced proliferation of hMSC. This reduction was due to a defect in Cyclin D1 expression and subsequent arrest in the G0/G1 phase of the cell cycle. hMSC growth is enhanced through culture medium supplementation with growth factors (GFs) such as Platelet-Derived Growth Factor (PDGF), basic Fibroblast Growth Factor (bFGF) or Epidermal Growth Factor (EGF). However, these supplements could not rescue the defect observed after ERK2 knockdown, suggesting a common signalling pathway used by these GFs for proliferation. In contrast, ERK1/2 may be dissociated from chemotactic signalling induced by the same GFs. Additionally, hMSCs were capable of differentiating into adipocytes even in the absence of either ERK1 or ERK2 proteins. Our data show that hMSCs do not require cell division to enter the adipogenic differentiation process, indicating that clonal amplification of these cells is not a critical step. However, cell-cell contact seems to be an essential requirement to be able to differentiate into mature adipocytes

  14. Introduction to contact mechanics

    CERN Document Server

    Fischer-Cripps, Anthony C

    2000-01-01

    Contact mechanics deals with the elastic or plastic contact between two solid objects, and is thus intimately connected with such topics as fracture, hardness, and elasticity.This text, intended for advanced undergraduates, begins with an introduction to the mechanical properties of materials, general fracture mechanics, and fractures in brittle solids.This is followed by a detailed discussion of stresses and the nature of elastic and elastic-plastic contact.

  15. A thermodynamic model of contact angle hysteresis.

    Science.gov (United States)

    Makkonen, Lasse

    2017-08-14

    When a three-phase contact line moves along a solid surface, the contact angle no longer corresponds to the static equilibrium angle but is larger when the liquid is advancing and smaller when the liquid is receding. The difference between the advancing and receding contact angles, i.e., the contact angle hysteresis, is of paramount importance in wetting and capillarity. For example, it determines the magnitude of the external force that is required to make a drop slide on a solid surface. Until now, fundamental origin of the contact angle hysteresis has been controversial. Here, this origin is revealed and a quantitative theory is derived. The theory is corroborated by the available experimental data for a large number of solid-liquid combinations. The theory is applied in modelling the contact angle hysteresis on a textured surface, and these results are also in quantitative agreement with the experimental data.

  16. New aspects in allergic contact dermatitis

    DEFF Research Database (Denmark)

    Mørtz, Charlotte G; Andersen, Klaus Ejner

    2008-01-01

    PURPOSE OF REVIEW: To give selected new information on contact allergy and allergic contact dermatitis with focus on diagnostic procedures and pitfalls. RECENT FINDINGS: Recent studies dealing with common contact allergens have improved our understanding of the relationship between positive patch...... contact dermatitis. The main culprits include fragrance chemicals, preservatives, and hair dyes. We are all more or less exposed to cosmetics and topical drugs on a daily basis. The labelling requirements given in the Cosmetics Directive is of great help in tracing the causative allergenic ingredients...... tests and the clinical interpretation and consequences for the patient. SUMMARY: Nickel allergy is still the most common contact allergy in Europe in spite of full implementation of the EU Nickel Directive in 2001. Contact allergens in cosmetics and topical drugs are another common cause of allergic...

  17. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... also available in Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at the Academy Financial ...

  18. Colors and contact dermatitis.

    Science.gov (United States)

    Bonamonte, Domenico; Foti, Caterina; Romita, Paolo; Vestita, Michelangelo; Angelini, Gianni

    2014-01-01

    The diagnosis of skin diseases relies on several clinical signs, among which color is of paramount importance. In this review, we consider certain clinical presentations of both eczematous and noneczematous contact dermatitis in which color plays a peculiar role orientating toward the right diagnosis. The conditions that will be discussed include specific clinical-morphologic subtypes of eczematous contact dermatitis, primary melanocytic, and nonmelanocytic contact hyperchromia, black dermographism, contact chemical leukoderma, and others. Based on the physical, chemical, and biologic factors underlying a healthy skin color, the various skin shades drawing a disease picture are thoroughly debated, stressing their etiopathogenic origins and histopathologic aspects.

  19. Mesenchymal Stem Cells in Cardiology

    Science.gov (United States)

    White, Ian A.; Sanina, Cristina; Balkan, Wayne; Hare, Joshua M.

    2017-01-01

    Cardiovascular disease (CVD) accounts for more deaths globally than any other single disease. There are on average 1.5 million episodes of myocardial infarction (heart attack) each year in the United States alone with roughly one third resulting in death. There is therefore a major need for developing new and effective strategies to promote cardiac repair. Intramyocardial transplantation of mesenchymal stem cells (MSCs) has emerged as a leading contender in the pursuit of clinical intervention and therapy. MSCs are potent mediators of cardiac repair and are therefore an attractive tool in the development of pre-clinical and clinical trials. MSCs are capable of secreting a large array of soluble factors, which have had demonstrated effects on pathogenic cardiac remolding, fibrosis, immune activation and cardiac stem cell proliferation within the damaged heart. MSCs are also capable of differentiation into cardiomyocytes, endothelial cells and vascular smooth muscle cells, although the relative contribution of trilineage differentiation and paracrine effectors on cardiac repair remains the subject of active investigation. PMID:27236666

  20. Contact dermatitis caused by preservatives.

    Science.gov (United States)

    Yim, Elizabeth; Baquerizo Nole, Katherine L; Tosti, Antonella

    2014-01-01

    Preservatives are biocidal chemicals added to food, cosmetics, and industrial products to prevent the growth of microorganisms. They are usually nontoxic and inexpensive and have a long shelf life. Unfortunately, they commonly cause contact dermatitis. This article reviews the most important classes of preservatives physicians are most likely to encounter in their daily practice, specifically isothiazolinones, formaldehyde and formaldehyde-releasers, iodopropynyl butylcarbamate, methyldibromoglutaronitrile, and parabens. For each preservative mentioned, the prevalence of sensitization, clinical presentation of contact dermatitis, patch testing concentrations, cross reactions, and related legislation will be discussed. Mandatory labeling of preservatives is required in some countries, but not required in others. Until policies are made, physicians and patients must be proactive in identifying potential sensitizers and removing their use. We hope that this article will serve as a guide for policy makers in creating legislation and future regulations on the use and concentration of certain preservatives in cosmetics and industrial products.

  1. Chromosomal contact permits transcription between coregulated genes

    CSIR Research Space (South Africa)

    Fanucchi, Stephanie

    2013-10-01

    Full Text Available . To ask whether chromosomal contacts are required for cotranscription in multigene complexes, we devised a strategy using TALENs to cleave and disrupt gene loops in a well-characterized multigene complex. Monitoring this disruption using RNA FISH...

  2. Contact engineering for nano-scale CMOS

    KAUST Repository

    Hussain, Muhammad Mustafa; Fahad, Hossain M.; Qaisi, Ramy M.

    2012-01-01

    . One of the critical requirements of transistor structure and fabrication is efficient contact engineering. To catch up with high performance information processing, transistors are going through continuous scaling process. However, it also imposes new

  3. Biocompatibility of quantum dots (CdSe/ZnS ) in human amniotic membrane-derived mesenchymal stem cells in vitro.

    Science.gov (United States)

    Wang, Gongping; Zeng, Guangwei; Wang, Caie; Wang, Huasheng; Yang, Bo; Guan, Fangxia; Li, Dongpeng; Feng, Xiaoshan

    2015-06-01

    Amniotic membrane-derived mesenchymal stem cells (hAM-dMSCs) are a potential source of mesenchymal stem cells which could be used to repair skin damage. The use of mesenchymal stem cells to repair skin damage requires safe, effective and biocompatible agents to evaluate the effectiveness of the result. Quantum dots (QDs) composed of CdSe/ZnS are semiconductor nanocrystals with broad excitation and narrow emission spectra, which have been considered as a new chemical and fluorescent substance for non-invasively labeling different cells in vitro and in vivo. This study investigated the cytotoxic effects of QDs on hAM-dMSCs at different times following labeling. Using 0.75, 1.5 and 3.0 μL between quantum dots, labeled human amniotic mesenchymal stem cells were collected on days 1, 2 and 4 and observed morphological changes, performed an MTT cell growth assay and flow cytometry for mesenchymal stem cells molecular markers. Quantum dot concentration 0.75 μg/mL labeled under a fluorescence microscope, cell morphology was observed, The MTT assay showed cells in the proliferative phase. Flow cytometry expression CD29, CD31, CD34, CD44, CD90, CD105 and CD106. Within a certain range of concentrations between quantum dots labeled human amniotic mesenchymal stem cells has good biocompatibility.

  4. EGCG Suppresses ERK5 Activation to Reverse Tobacco Smoke-Triggered Gastric Epithelial-Mesenchymal Transition in BALB/c Mice

    Directory of Open Access Journals (Sweden)

    Ling Lu

    2016-07-01

    Full Text Available Tobacco smoke is an important risk factor of gastric cancer. Epithelial-mesenchymal transition is a crucial pathophysiological process in cancer development. ERK5 regulation of epithelial-mesenchymal transition may be sensitive to cell types and/or the cellular microenvironment and its role in the epithelial-mesenchymal transition process remain elusive. Epigallocatechin-3-gallate (EGCG is a promising chemopreventive agent for several types of cancers. In the present study we investigated the regulatory role of ERK5 in tobacco smoke-induced epithelial-mesenchymal transition in the stomach of mice and the preventive effect of EGCG. Exposure of mice to tobacco smoke for 12 weeks reduced expression of epithelial markers E-cadherin, ZO-1, and CK5, while the expression of mesenchymal markers Snail-1, Vimentin, and N-cadherin were increased. Importantly, we demonstrated that ERK5 modulated tobacco smoke-mediated epithelial-mesenchymal transition in mice stomach, as evidenced by the findings that tobacco smoke elevated ERK5 activation, and that tobacco smoke-triggered epithelial-mesenchymal transition was reversed by ERK5 inhibition. Treatment of EGCG (100 mg/kg BW effectively attenuated tobacco smoke-triggered activation of ERK5 and epithelial-mesenchymal transition alterations in mice stomach. Collectively, these data suggested that ERK5 was required for tobacco smoke-triggered gastric epithelial-mesenchymal transition and that EGCG suppressed ERK5 activation to reverse tobacco smoke-triggered gastric epithelial-mesenchymal transition in BALB/c mice. These findings provide new insights into the mechanism of tobacco smoke-associated gastric tumorigenesis and the chemoprevention of tobacco smoke-associated gastric cancer.

  5. Mesenchymal precursor cells maintain the differentiation and proliferation potentials of breast epithelial cells

    Science.gov (United States)

    2014-01-01

    Introduction Stromal-epithelial interactions play a fundamental role in tissue homeostasis, controlling cell proliferation and differentiation. Not surprisingly, aberrant stromal-epithelial interactions contribute to malignancies. Studies of the cellular and molecular mechanisms underlying these interactions require ex vivo experimental model systems that recapitulate the complexity of human tissue without compromising the differentiation and proliferation potentials of human primary cells. Methods We isolated and characterized human breast epithelial and mesenchymal precursors from reduction mammoplasty tissue and tagged them with lentiviral vectors. We assembled heterotypic co-cultures and compared mesenchymal and epithelial cells to cells in corresponding monocultures by analyzing growth, differentiation potentials, and gene expression profiles. Results We show that heterotypic culture of non-immortalized human primary breast epithelial and mesenchymal precursors maintains their proliferation and differentiation potentials and constrains their growth. We further describe the gene expression profiles of stromal and epithelial cells in co-cultures and monocultures and show increased expression of the tumor growth factor beta (TGFβ) family member inhibin beta A (INHBA) in mesenchymal cells grown as co-cultures compared with monocultures. Notably, overexpression of INHBA in mesenchymal cells increases colony formation potential of epithelial cells, suggesting that it contributes to the dynamic reciprocity between breast mesenchymal and epithelial cells. Conclusions The described heterotypic co-culture system will prove useful for further characterization of the molecular mechanisms mediating interactions between human normal or neoplastic breast epithelial cells and the stroma, and will provide a framework to test the relevance of the ever-increasing number of oncogenomic alterations identified in human breast cancer. PMID:24916766

  6. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... eye-care professional. Retailers that sell contacts without a prescription are breaking the law, and may be fined $11,000 per violation. "Many of the lenses found online or in beauty salons, novelty shops or in pop-up ... contact lenses from a retailer that does not ask for a prescription. ...

  7. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Get follow up exams with your eye care provider. If you notice redness, swelling, excessive discharge, pain or discomfort from wearing contact lenses, remove the lenses and seek immediate medical attention from an ophthalmologist. Related resources: Learn how to properly care for contact lenses . ...

  8. Sciences & Nature: Contact

    African Journals Online (AJOL)

    Principal Contact. Ehouan Etienne Ehile Professor University of Abobo-Adjamé 02 BP 801 Abidjan 02. Phone: (+225) 2030 4201. Fax: (+225) 2030 4203. Email: eh_ehile@yahoo.fr. Support Contact. Irie Zoro Bi Email: banhiakalou@yahoo.fr. ISSN: 1812-0741. AJOL African Journals Online. HOW TO USE AJOL.

  9. Contact Us | DOepatents

    Science.gov (United States)

    advance. Your help is appreciated. Contact us by email Email doepatentscomments@osti.gov NOTE: Email us by phone Phone Phone (865) 241-5275 Contact us in writing Mail U.S. Department of Energy Office of non-federal websites. Their policies may differ from this site. Javascript Not Enabled Email Link

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... eye-care team . Consumer warning about the improper use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering buying approved by the FDA? Check the FDA's database of approved contact lenses . Related Stories Prevent Infection ...

  11. Contact dermatitis. A review

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Benezra, C; Burrows, D

    1987-01-01

    In recent years, there has been a dramatic rise in our understanding of contact dermatitis. This paper is a review of our knowledge of the mechanisms involved in contact dermatitis and related phenomena, the investigation of these events and the emergence of significant new allergens during...

  12. Contact Hamiltonian mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Bravetti, Alessandro, E-mail: alessandro.bravetti@iimas.unam.mx [Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, A. P. 70543, México, DF 04510 (Mexico); Cruz, Hans, E-mail: hans@ciencias.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A. P. 70543, México, DF 04510 (Mexico); Tapias, Diego, E-mail: diego.tapias@nucleares.unam.mx [Facultad de Ciencias, Universidad Nacional Autónoma de México, A.P. 70543, México, DF 04510 (Mexico)

    2017-01-15

    In this work we introduce contact Hamiltonian mechanics, an extension of symplectic Hamiltonian mechanics, and show that it is a natural candidate for a geometric description of non-dissipative and dissipative systems. For this purpose we review in detail the major features of standard symplectic Hamiltonian dynamics and show that all of them can be generalized to the contact case.

  13. Contact Quality in Participation

    DEFF Research Database (Denmark)

    Simonsen, Jesper; Jensen, Olav Storm

    2016-01-01

    We investigate the concept of participation from the perspective of quality of the contact in the communicative interactions between participants. We argue for the need for an academic-personal competence that qualifies the human contact central in all Participatory Design (PD) activities as a way...

  14. Nigerian Food Journal: Contact

    African Journals Online (AJOL)

    Nigerian Food Journal. ... Nigerian Food Journal: Contact. Journal Home > About the Journal > Nigerian Food Journal: Contact. Log in or Register to get access to full text downloads. ... Mailing Address. Department of Food Science and Technology University of Agriculture, Makurdi, Nigeria ...

  15. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... like a suction cup." Halloween is a popular time for people to use colored contact lenses to enhance their costumes. From ... MD, professor of ophthalmology at Case Western Reserve University in Cleveland. "This is far ... Use Facts About Colored Contacts and Halloween Safety Colored ...

  16. Contact materials for nanoelectronics

    KAUST Repository

    Alshareef, Husam N.

    2011-02-01

    In this article, we review current research activities in contact material development for electronic and nanoelectronic devices. A fundamental issue in contact materials research is to understand and control interfacial reactions and phenomena that modify the expected device performance. These reactions have become more challenging and more difficult to control as new materials have been introduced and as device sizes have entered the deep nanoscale. To provide an overview of this field of inquiry, this issue of MRS Bulletin includes articles on gate and contact materials for Si-based devices, junction contact materials for Si-based devices, and contact materials for alternate channel substrates (Ge and III-V), nanodevices. © 2011 Materials Research Society.

  17. Noneczematous Contact Dermatitis

    Science.gov (United States)

    Foti, Caterina; Vestita, Michelangelo; Angelini, Gianni

    2013-01-01

    Irritant or allergic contact dermatitis usually presents as an eczematous process, clinically characterized by erythematoedematovesicous lesions with intense itching in the acute phase. Such manifestations become erythematous-scaly as the condition progresses to the subacute phase and papular-hyperkeratotic in the chronic phase. Not infrequently, however, contact dermatitis presents with noneczematous features. The reasons underlying this clinical polymorphism lie in the different noxae and contact modalities, as well as in the individual susceptibility and the various targeted cutaneous structures. The most represented forms of non-eczematous contact dermatitis include the erythema multiforme-like, the purpuric, the lichenoid, and the pigmented kinds. These clinical entities must obviously be discerned from the corresponding “pure” dermatitis, which are not associated with contact with exogenous agents. PMID:24109520

  18. Sources of adult mesenchymal stem cells for ligament and tendon tissue engineering.

    Science.gov (United States)

    Dhinsa, Baljinder S; Mahapatra, Anant N; Khan, Wasim S

    2015-01-01

    Tendon and ligament injuries are common, and repair slowly with reduced biomechanical properties. With increasing financial demands on the health service and patients to recover from tendon and ligament injuries faster, and with less morbidity, health professionals are exploring new treatment options. Tissue engineering may provide the answer, with its unlimited source of natural cells that in the correct environment may improve repair and regeneration of tendon and ligament tissue. Mesenchymal stem cells have demonstrated the ability to self renew and have multilineage differentiation potential. The use of bone marrow-derived mesenchymal stem cells has been reported, however significant in vitro culture expansion is required due to the low yield of cells, which has financial implications. Harvesting of bone marrow cells also has associated morbidity. Several studies have looked at alternative sources for mesenchymal stem cells. Reports in literature from animal studies have been encouraging, however further work is required. This review assesses the potential sources of mesenchymal stem cells for tissue engineering in tendons and ligaments.

  19. CD54-Mediated Interaction with Pro-inflammatory Macrophages Increases the Immunosuppressive Function of Human Mesenchymal Stromal Cells

    OpenAIRE

    Espagnolle, Nicolas; Balguerie, Ad?lie; Arnaud, Emmanuelle; Senseb?, Luc; Varin, Audrey

    2017-01-01

    Summary: Mesenchymal stromal cells (MSCs) sense and modulate inflammation and represent potential clinical treatment for immune disorders. However, many details of the bidirectional interaction of MSCs and the innate immune compartment are still unsolved. Here we describe an unconventional but functional interaction between pro-inflammatory classically activated macrophages (M1MΦ) and MSCs, with CD54 playing a central role. CD54 was upregulated and enriched specifically at the contact area be...

  20. Contact lens rehabilitation following repaired corneal perforations

    Science.gov (United States)

    Titiyal, Jeewan S; Sinha, Rajesh; Sharma, Namrata; Sreenivas, V; Vajpayee, Rasik B

    2006-01-01

    Background Visual outcome following repair of post-traumatic corneal perforation may not be optimal due to presence of irregular keratometric astigmatism. We performed a study to evaluate and compare rigid gas permeable contact lens and spectacles in visual rehabilitation following perforating corneal injuries. Method Eyes that had undergone repair for corneal perforating injuries with or without lens aspiration were fitted rigid gas permeable contact lenses. The fitting pattern and the improvement in visual acuity by contact lens over spectacle correction were noted. Results Forty eyes of 40 patients that had undergone surgical repair of posttraumatic corneal perforations were fitted rigid gas permeable contact lenses for visual rehabilitation. Twenty-four eyes (60%) required aphakic contact lenses. The best corrected visual acuity (BCVA) of ≥ 6/18 in the snellen's acuity chart was seen in 10 (25%) eyes with spectacle correction and 37 (92.5%) eyes with the use of contact lens (p < 0.001). The best-corrected visual acuity with spectacles was 0.20 ± 0.13 while the same with contact lens was 0.58 ± 0.26. All the patients showed an improvement of ≥ 2 lines over spectacles in the snellen's acuity chart with contact lens. Conclusion Rigid gas permeable contact lenses are better means of rehabilitation in eyes that have an irregular cornea due to scars caused by perforating corneal injuries. PMID:16536877

  1. Contacts to semiconductors

    International Nuclear Information System (INIS)

    Tove, P.A.

    1975-08-01

    Contacts to semiconductors play an important role in most semiconductor devices. These devices range from microelectronics to power components, from high-sensitivity light or radiation detectors to light-emitting of microwave-generating components. Silicon is the dominating material but compound semiconductors are increasing in importance. The following survey is an attempt to classify contact properties and the physical mechanisms involved, as well as fabrication methods and methods of investigation. The main interest is in metal-semiconductor type contacts where a few basic concepts are dealt with in some detail. (Auth.)

  2. Hypoxia activated EGFR signaling induces epithelial to mesenchymal transition (EMT.

    Directory of Open Access Journals (Sweden)

    Ashish Misra

    Full Text Available Metastasis is a multi-step process which requires the conversion of polarized epithelial cells to mesenchymal cells, Epithelial-Mesenchymal Transition (EMT. EMT is essential during embryonic morphogenesis and has been implicated in the progression of primary tumors towards metastasis. Hypoxia is known to induce EMT; however the molecular mechanism is still poorly understood. Using the A431 epithelial cancer cell line, we show that cells grown under hypoxic conditions migrated faster than cells grown under normal oxygen environment. Cells grown under hypoxia showed reduced adhesion to the extracellular matrix (ECM probably due to reduced number of Vinculin patches. Growth under hypoxic conditions also led to down regulation of E-cadherin and up regulation of vimentin expression. The increased motility of cells grown under hypoxia could be due to redistribution of Rac1 to the plasma membrane as opposed to increased expression of Rac1. EGF (Epidermal Growth Factor is a known inducer of EMT and growth of A431 cells in the absence of oxygen led to increased expression of EGFR (EGF Receptor. Treatment of A431 cells with EGF led to reduced cell adhesion to ECM, increased cell motility and other EMT characteristics. Furthermore, this transition was blocked by the monoclonal antibody Cetuximab. Cetuximab also blocked the hypoxia-induced EMT suggesting that cell growth under hypoxic conditions led to activation of EGFR signaling and induction of EMT phenotype.

  3. A case of intracranial mesenchymal chondrosarcoma

    International Nuclear Information System (INIS)

    Hoshino, Masami; Tanji, Hiroyuki; Watanabe, Masakazu

    1981-01-01

    Intracranial mesenchymal chondrosarcoma is very rare, only 14 cases being reported in Europe and in the United States of America. Recently we experienced a case in which the follow-up indicating computed tomograms (CT) demonstrated interesting data on the radiosensitivity of this tumor. The patient, a 14-year-old female was admitted to our hospital with the complaint of left hemiplegia which had gradually progressed. CT revealed an area spreading upward from the right median base of the skull and consisted of two components showing (A) a density as high as that of calcium and (B) a density higher than that of surrounding brain tissue, but much lower than that of calcium. Temporoparietal craniotomy was performed to resect approximately one-half of the tumor. Histological finding revealed mesenchymal chondrosarcoma. The component-A was though to be a cartilaginous tissue, and-B to be an undifferentiated mesenchymal tissue. Postoperative irradiation of 7,000 rad was initiated. The effect of radiotherapy as seen on computed tomograms is as follows, (1) decrease in the volume of the tumor by 26%, (2) decrease in density and enhancement of the area which is considered to be the undifferentiated mesenchymal cells, (3) mild reduction of the area which is considered to be the caltilaginous tissue, and (4) a very high density of the entire tumor similar in degree to that of the bone one year later. These results suggested that radiotherapy is effective for this tumor. (author)

  4. Andrographolide suppresses epithelial mesenchymal transition by ...

    Indian Academy of Sciences (India)

    Epithelial mesenchymal transition (EMT) of lens epithelial cells (LECs) may contribute to the development of posterior capsular opacification (PCO), which leads to visual impairment. Andrographolide has been shown to have therapeutic potential against various cancers. However, its effect on human LECs is still unknown.

  5. Mesenchymal stem cells in oral reconstructive surgery

    DEFF Research Database (Denmark)

    Jakobsen, C; Sørensen, J A; Kassem, M

    2013-01-01

    This study evaluated clinical outcomes following intraoperative use of adult mesenchymal stem cells (MSCs) in various oral reconstructive procedures. PubMed was searched without language restrictions from 2000 to 2011 using the search words stem cell, oral surgery, tissue engineering, sinus lift...

  6. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... not been properly fitted by an eye care professional, the lenses stuck to my eye like a ... prescription and proper fitting by an eye-care professional. Retailers that sell contacts without a prescription are ...

  7. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... about the members of the eye-care team . Consumer warning about the improper use of colored contact ... About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of ...

  8. Contact Line Dynamics

    Science.gov (United States)

    Kreiss, Gunilla; Holmgren, Hanna; Kronbichler, Martin; Ge, Anthony; Brant, Luca

    2017-11-01

    The conventional no-slip boundary condition leads to a non-integrable stress singularity at a moving contact line. This makes numerical simulations of two-phase flow challenging, especially when capillarity of the contact point is essential for the dynamics of the flow. We will describe a modeling methodology, which is suitable for numerical simulations, and present results from numerical computations. The methodology is based on combining a relation between the apparent contact angle and the contact line velocity, with the similarity solution for Stokes flow at a planar interface. The relation between angle and velocity can be determined by theoretical arguments, or from simulations using a more detailed model. In our approach we have used results from phase field simulations in a small domain, but using a molecular dynamics model should also be possible. In both cases more physics is included and the stress singularity is removed.

  9. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ... away without suffering an eye injury. However, the natural protective mechanisms of the eye – such as the ...

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... about the members of the eye-care team . Consumer warning about the improper use of colored contact ... a laser pointer several times, according to a report published this month in the New England Journal ...

  11. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are ... this month in the New England Journal of Medicine. Unfortunately, this kind of injury is all too ...

  12. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... a souvenir shop, but 10 hours after she first put in a pair of colored contact lenses, ... APR 24, 2018 By Kate Rauch In a first, scientists in China have created artificial photoreceptors to ...

  13. GAS-FOVEAL CONTACT

    DEFF Research Database (Denmark)

    Alberti, Mark; la Cour, Morten

    2018-01-01

    PURPOSE: To compare gas-foveal contact in face-down positioning (FDP) and nonsupine positioning (NSP), to analyze causes of gas-foveal separation and to determine how gas-foveal contact affects clinical outcome after idiopathic macular hole repair. METHODS: Single center, randomized controlled...... study. Participants with an idiopathic macular hole were allocated to either FDP or NSP. Primary outcome was gas-foveal contact, calculated by analyzing positioning in relation to intraocular gas fill. Positioning was measured with an electronic device recording positioning for 72 hours postoperatively....... RESULTS: Positioning data were available for 33/35 in the FDP group and 35/37 in the NSP group, thus results are based on 68 analyzed participants. Median gas-foveal contact was 99.82% (range 73.6-100.0) in the FDP group and 99.57% (range 85.3-100.0) in the NSP group (P = 0.22). In a statistical model...

  14. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Sep. 26, 2013 It started as an impulsive buy from a souvenir shop, but 10 hours after ... are being sold illegally," Dr. Steinemann said. Never buy colored contact lenses from a retailer that does ...

  15. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ... 2018 By Dan T. Gudgel Do you know what the difference is between ophthalmologists and optometrists? A ...

  16. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Halloween or any time of year, follow these guidelines: Get an eye exam from a licensed eye ... available in Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the ...

  17. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... seek immediate medical attention from an ophthalmologist. Related resources: Learn how to properly care for contact lenses . ... have given blind patients some functional vision, using human embryonic stem cells. Two blind patients regained enough ...

  18. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... MD, professor of ophthalmology at Case Western Reserve University in Cleveland. "This is far from the truth." Real People, Real Problems with Colored Contact Lenses Julian: Teenager Blinded In ...

  19. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... also available in Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms ...

  20. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... lentes de contacto de color Sep. 26, 2013 It started as an impulsive buy from a souvenir ... Can Ruin Vision Eye Makeup Safety In fact, it is illegal to sell colored contact lenses without ...

  1. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... With Proper Contact Lens Care Apr 23, 2018 Solar Eclipse Inflicts Damage in the Shape of the ... edging closer, thanks to a wave of new technologies aiming to fix failing eye parts with human- ...

  2. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... videos on your website Promotional materials for eye health observances EyeSmart resources are also available in Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at ...

  3. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... valid prescription that includes the brand name, lens measurements, and expiration date. Purchase the colored contact lenses ... with human-made versions. U.S. News Highlights the Value of Ophthalmologists APR 20, 2018 By Dan T. ...

  4. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... sell contacts without a prescription are breaking the law, and may be fined $11,000 per violation. " ... Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms ...

  5. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... sell contacts without a prescription are breaking the law, and may be fined $11,000 per violation. " ... 13, 2017 Histoplasmosis Diagnosis Sep 01, 2017 How common is retinal detachment for people with high myopia? ...

  6. Colored Contact Lens Dangers

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    Full Text Available ... Ophthalmology/Strabismus Ocular Pathology/Oncology Oculoplastics/Orbit Refractive Management/Intervention Retina/Vitreous Uveitis Focus ... Eye Health A-Z Symptoms Glasses & Contacts Tips & ...

  7. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering buying approved by the ... Service For Advertisers For Media Ophthalmology Job Center © American ...

  8. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... be purchased over-the-counter or on the Internet," says Thomas Steinemann, MD, professor of ophthalmology at ... also available in Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About ...

  9. Ergonomics SA: Contact

    African Journals Online (AJOL)

    Principal Contact. Mrs June McDougall. Rhodes University. Department of Human Kinetics and Ergonomics. P.O. Box 94. Rhodes University. Grahamstown. 6140. Phone: +27 46 6038471. Email: j.mcdougall@ru.ac.za ...

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering buying approved by ... 23, 2018 Solar Eclipse Inflicts Damage in the Shape of ...

  11. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... colored contact lenses to enhance their costumes. From blood-drenched vampire eyes to glow-in-the-dark ... properly fitted may scratch the eye or cause blood vessels to grow into the cornea. Even if ...

  12. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... to the journals may be interrupted during this time. We are working to resolve the issue quickly ... like a suction cup." Halloween is a popular time for people to use colored contact lenses to ...

  13. Tomato contact dermatitis

    DEFF Research Database (Denmark)

    Paulsen, Evy; Christensen, Lars P; Andersen, Klaus Ejner

    2012-01-01

    The tomato plant (Solanum lycopersicum) is an important crop worldwide. Whereas immediate-type reactions to tomato fruits are well known, contact dermatitis caused by tomatoes or tomato plants is rarely reported. The aims of this study were to present new data on contact sensitization to tomato...... plants and review the literature on contact dermatitis caused by both plants and fruits. An ether extract of tomato plants made as the original oleoresin plant extracts, was used in aimed patch testing, and between 2005 and 2011. 8 of 93 patients (9%) tested positive to the oleoresin extracts....... This prevalence is in accordance with the older literature that reports tomato plants as occasional sensitizers. The same applies to tomato fruits, which, in addition, may cause protein contact dermatitis. The allergens of the plant are unknown, but both heat-stable and heat-labile constituents seem...

  14. Fragrance allergic contact dermatitis.

    Science.gov (United States)

    Cheng, Judy; Zug, Kathryn A

    2014-01-01

    Fragrances are a common cause of allergic contact dermatitis in Europe and in North America. They can affect individuals at any age and elicit a spectrum of reactions from contact urticaria to systemic contact dermatitis. Growing recognition of the widespread use of fragrances in modern society has fueled attempts to prevent sensitization through improved allergen identification, labeling, and consumer education. This review provides an overview and update on fragrance allergy. Part 1 discusses the epidemiology and evaluation of suspected fragrance allergy. Part 2 reviews screening methods, emerging fragrance allergens, and management of patients with fragrance contact allergy. This review concludes by examining recent legislation on fragrances and suggesting potential additions to screening series to help prevent and detect fragrance allergy.

  15. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology ...

  16. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... be purchased over-the-counter or on the Internet," says Thomas Steinemann, MD, professor of ophthalmology at ... about the members of the eye-care team . Consumer warning about the improper use of colored contact ...

  17. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Peligros asociados con los lentes de contacto de color Sep. 26, 2013 It started as an impulsive ... Halloween is a popular time for people to use colored contact lenses to enhance their costumes. From ...

  18. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of ...

  19. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... be purchased over-the-counter or on the Internet," says Thomas Steinemann, MD, professor of ophthalmology at ... ask for a prescription. There is no such thing as a "one size fits all" contact lens. ...

  20. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... also available in Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical ...

  1. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Ophthalmology/Strabismus Ocular Pathology/Oncology Oculoplastics/Orbit Refractive Management/Intervention Retina/Vitreous Uveitis Focus ... Halloween Hazard: The Hidden Dangers of Buying Decorative Contact Lenses Without ...

  2. Microenvironmental cues enhance mesenchymal stem cell-mediated immunomodulation and regulatory T-cell expansion.

    Science.gov (United States)

    Kadle, Rohini L; Abdou, Salma A; Villarreal-Ponce, Alvaro P; Soares, Marc A; Sultan, Darren L; David, Joshua A; Massie, Jonathan; Rifkin, William J; Rabbani, Piul; Ceradini, Daniel J

    2018-01-01

    Mesenchymal stem cells (MSCs) are known to both have powerful immunosuppressive properties and promote allograft tolerance. Determining the environmental oxygen tension and inflammatory conditions under which MSCs are optimally primed for this immunosuppressive function is essential to their utilization in promoting graft tolerance. Of particular interest is the mechanisms governing the interaction between MSCs and regulatory T cells (Tregs), which is relatively unknown. We performed our experiments utilizing rat bone marrow derived MSCs. We observed that priming MSCs in hypoxia promotes maintenance of stem-like characteristics, with greater expression of typical MSC cell-surface markers, increased proliferation, and maintenance of differentiation potential. Addition of autologous MSCs to CD4+/allogeneic endothelial cell (EC) co-culture increases regulatory T cell (Treg) proliferation, which is further enhanced when MSCs are primed in hypoxia. Furthermore, MSC-mediated Treg expansion does not require direct cell-cell contact. The expression of indolamine 2,3-dioxygenase, a mediator of MSC immunomodulation, increases when MSCs are primed in hypoxia, and inhibition of IDO significantly decreases the expansion of Tregs. Priming with inflammatory cytokines IFNγ and TNFα increases also expression of markers associated with MSC immunomodulatory function, but decreases MSC proliferation. The expression of IDO also increases when MSCs are primed with inflammatory cytokines. However, there is no increase in Treg expansion when MSCs are primed with IFNγ, suggesting an alternate mechanism for inflammatory-stimulated MSC immunomodulation. Overall, these results suggest that MSCs primed in hypoxia or inflammatory conditions are optimally primed for immunosuppressive function. These results provide a clearer picture of how to enhance MSC immunomodulation for clinical use.

  3. 75 FR 6032 - National Contact Center; Submission for OMB Review; National Contact Center Customer Evaluation...

    Science.gov (United States)

    2010-02-05

    ... for OMB Review; National Contact Center Customer Evaluation Survey AGENCY: Citizen Services and Communications, Federal Consumer Information Center, GSA. ACTION: Notice of request for comments regarding a... collection requirement regarding the National Contact Center customer evaluation survey. A request for public...

  4. Lettuce contact allergy.

    Science.gov (United States)

    Paulsen, Evy; Andersen, Klaus E

    2016-02-01

    Lettuce (Lactuca sativa L.) and its varieties are important vegetable crops worldwide. They are also well-known, rarely reported, causes of contact allergy. As lettuce allergens and extracts are not commercially available, the allergy may be underdiagnosed. The aims of this article are to present new data on lettuce contact allergy and review the literature. Lettuce is weakly allergenic, and occupational cases are mainly reported. Using aimed patch testing in Compositae-allergic patients, two recent Danish studies showed prevalence rates of positive lettuce reactions of 11% and 22%. The majority of cases are non-occupational, and may partly be caused by cross-reactivity. The sesquiterpene lactone mix seems to be a poor screening agent for lettuce contact allergy, as the prevalence of positive reactions is significantly higher in non-occupationally sensitized patients. Because of the easy degradability of lettuce allergens, it is recommended to patch test with freshly cut lettuce stem and supplement this with Compositae mix. As contact urticaria and protein contact dermatitis may present as dermatitis, it is important to perform prick-to-prick tests, and possibly scratch patch tests as well. Any person who is occupationally exposed to lettuce for longer periods, especially atopics, amateur gardeners, and persons keeping lettuce-eating pets, is potentially at risk of developing lettuce contact allergy. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. In vitro mesenchymal stem cell response to a CO{sub 2} laser modified polymeric material

    Energy Technology Data Exchange (ETDEWEB)

    Waugh, D.G., E-mail: d.waugh@chester.ac.uk [Laser Engineering and Manufacturing Research Centre, Faculty of Science and Engineering, University of Chester, Chester CH1 4BJ (United Kingdom); Hussain, I. [School of Life Sciences, Brayford Pool, University of Lincoln, Lincoln LN6 7TS (United Kingdom); Lawrence, J.; Smith, G.C. [Laser Engineering and Manufacturing Research Centre, Faculty of Science and Engineering, University of Chester, Chester CH1 4BJ (United Kingdom); Cosgrove, D. [School of Life Sciences, Brayford Pool, University of Lincoln, Lincoln LN6 7TS (United Kingdom); Toccaceli, C. [Laser Engineering and Manufacturing Research Centre, Faculty of Science and Engineering, University of Chester, Chester CH1 4BJ (United Kingdom)

    2016-10-01

    With an ageing world population it is becoming significantly apparent that there is a need to produce implants and platforms to manipulate stem cell growth on a pharmaceutical scale. This is needed to meet the socio-economic demands of many countries worldwide. This paper details one of the first ever studies in to the manipulation of stem cell growth on CO{sub 2} laser surface treated nylon 6,6 highlighting its potential as an inexpensive platform to manipulate stem cell growth on a pharmaceutical scale. Through CO{sub 2} laser surface treatment discrete changes to the surfaces were made. That is, the surface roughness of the nylon 6,6 was increased by up to 4.3 μm, the contact angle was modulated by up to 5° and the surface oxygen content increased by up to 1 atom %. Following mesenchymal stem cell growth on the laser treated samples, it was identified that CO{sub 2} laser surface treatment gave rise to an enhanced response with an increase in viable cell count of up to 60,000 cells/ml when compared to the as-received sample. The effect of surface parameters modified by the CO{sub 2} laser surface treatment on the mesenchymal stem cell response is also discussed along with potential trends that could be identified to govern the mesenchymal stem cell response.

  6. Patients with multiple contact allergies

    DEFF Research Database (Denmark)

    Carlsen, Berit Christina; Andersen, Klaus Ejner; Menné, Torkil

    2008-01-01

    Patients with multiple contact allergies, also referred to as polysensitized, are more frequent than predicted from prevalence of single sensitivities. The understanding of why some people develop multiple contact allergies, and characterization of patients with multiple contact allergies...... of developing multiple contact allergies. Evidence of allergen clusters among polysensitized individuals is also reviewed. The literature supports the idea that patients with multiple contact allergies constitute a special entity within the field of contact allergy. There is no generally accepted definition...... of patients with multiple contact allergies. We suggest that contact allergy to 3 or more allergens are defined as multiple contact allergies....

  7. A SHH-FOXF1-BMP4 signaling axis regulating growth and differentiation of epithelial and mesenchymal tissues in ureter development.

    Directory of Open Access Journals (Sweden)

    Tobias Bohnenpoll

    2017-08-01

    Full Text Available The differentiated cell types of the epithelial and mesenchymal tissue compartments of the mature ureter of the mouse arise in a precise temporal and spatial sequence from uncommitted precursor cells of the distal ureteric bud epithelium and its surrounding mesenchyme. Previous genetic efforts identified a member of the Hedgehog (HH family of secreted proteins, Sonic hedgehog (SHH as a crucial epithelial signal for growth and differentiation of the ureteric mesenchyme. Here, we used conditional loss- and gain-of-function experiments of the unique HH signal transducer Smoothened (SMO to further characterize the cellular functions and unravel the effector genes of HH signaling in ureter development. We showed that HH signaling is not only required for proliferation and SMC differentiation of cells of the inner mesenchymal region but also for survival of cells of the outer mesenchymal region, and for epithelial proliferation and differentiation. We identified the Forkhead transcription factor gene Foxf1 as a target of HH signaling in the ureteric mesenchyme. Expression of a repressor version of FOXF1 in this tissue completely recapitulated the mesenchymal and epithelial proliferation and differentiation defects associated with loss of HH signaling while re-expression of a wildtype version of FOXF1 in the inner mesenchymal layer restored these cellular programs when HH signaling was inhibited. We further showed that expression of Bmp4 in the ureteric mesenchyme depends on HH signaling and Foxf1, and that exogenous BMP4 rescued cell proliferation and epithelial differentiation in ureters with abrogated HH signaling or FOXF1 function. We conclude that SHH uses a FOXF1-BMP4 module to coordinate the cellular programs for ureter elongation and differentiation, and suggest that deregulation of this signaling axis occurs in human congenital anomalies of the kidney and urinary tract (CAKUT.

  8. A SHH-FOXF1-BMP4 signaling axis regulating growth and differentiation of epithelial and mesenchymal tissues in ureter development.

    Science.gov (United States)

    Bohnenpoll, Tobias; Wittern, Anna B; Mamo, Tamrat M; Weiss, Anna-Carina; Rudat, Carsten; Kleppa, Marc-Jens; Schuster-Gossler, Karin; Wojahn, Irina; Lüdtke, Timo H-W; Trowe, Mark-Oliver; Kispert, Andreas

    2017-08-01

    The differentiated cell types of the epithelial and mesenchymal tissue compartments of the mature ureter of the mouse arise in a precise temporal and spatial sequence from uncommitted precursor cells of the distal ureteric bud epithelium and its surrounding mesenchyme. Previous genetic efforts identified a member of the Hedgehog (HH) family of secreted proteins, Sonic hedgehog (SHH) as a crucial epithelial signal for growth and differentiation of the ureteric mesenchyme. Here, we used conditional loss- and gain-of-function experiments of the unique HH signal transducer Smoothened (SMO) to further characterize the cellular functions and unravel the effector genes of HH signaling in ureter development. We showed that HH signaling is not only required for proliferation and SMC differentiation of cells of the inner mesenchymal region but also for survival of cells of the outer mesenchymal region, and for epithelial proliferation and differentiation. We identified the Forkhead transcription factor gene Foxf1 as a target of HH signaling in the ureteric mesenchyme. Expression of a repressor version of FOXF1 in this tissue completely recapitulated the mesenchymal and epithelial proliferation and differentiation defects associated with loss of HH signaling while re-expression of a wildtype version of FOXF1 in the inner mesenchymal layer restored these cellular programs when HH signaling was inhibited. We further showed that expression of Bmp4 in the ureteric mesenchyme depends on HH signaling and Foxf1, and that exogenous BMP4 rescued cell proliferation and epithelial differentiation in ureters with abrogated HH signaling or FOXF1 function. We conclude that SHH uses a FOXF1-BMP4 module to coordinate the cellular programs for ureter elongation and differentiation, and suggest that deregulation of this signaling axis occurs in human congenital anomalies of the kidney and urinary tract (CAKUT).

  9. Contact allergy to epoxy resin

    DEFF Research Database (Denmark)

    Bangsgaard, Nannie; Thyssen, Jacob Pontoppidan; Menné, Torkil

    2012-01-01

    Background. Epoxy resin monomers are strong skin sensitizers that are widely used in industrial sectors. In Denmark, the law stipulates that workers must undergo a course on safe handling of epoxy resins prior to occupational exposure, but the effectiveness of this initiative is largely unknown...... in an educational programme. Conclusion. The 1% prevalence of epoxy resin contact allergy is equivalent to reports from other countries. The high occurrence of epoxy resin exposure at work, and the limited use of protective measures, indicate that reinforcement of the law is required....

  10. Indian hedgehog regulates intestinal stem cell fate through epithelial-mesenchymal interactions during development

    NARCIS (Netherlands)

    Kosinski, C.; Stange, D.E.; Xu, C.; Chan, A.S.; Ho, C.; Yuen, S.T.; Mifflin, R.C.; Powell, D.W.; Clevers, H.; Leung, S.Y.; Chen, X.N.

    2010-01-01

    BACKGROUND & AIMS: Intestinal stem cells (ISCs) are regulated by the mesenchymal environment via physical interaction and diffusible factors. We examined the role of Indian hedgehog (Ihh) in mesenchymal organization and the mechanisms by which perturbations in epithelial-mesenchymal interactions

  11. Acrylate Systemic Contact Dermatitis.

    Science.gov (United States)

    Sauder, Maxwell B; Pratt, Melanie D

    2015-01-01

    Acrylates, the 2012 American Contact Dermatitis Society allergen of the year, are found in a range of products including the absorbent materials within feminine hygiene pads. When fully polymerized, acrylates are nonimmunogenic; however, if not completely cured, the monomers can be potent allergens.A 28-year-old woman is presented, who had her teeth varnished with Isodan (Septodont, Saint-Maur-des-Fossés, France) containing HEMA (2-hydroxyethyl methacrylate) with no initial reaction. Approximately 1 month later, the patient developed a genital dermatitis secondary to her feminine hygiene pads. The initial reaction resolved, but 5 months later, the patient developed a systemic contact dermatitis after receiving a second varnishing.The patient was dramatically patch test positive to many acrylates. This case demonstrates a reaction to likely unpolymerized acrylates within a feminine hygiene pad, as well as broad cross-reactivity or cosensitivity to acrylates, and possibly a systemic contact dermatitis with systemic re-exposure to unpolymerized acrylates.

  12. Shoe allergic contact dermatitis.

    Science.gov (United States)

    Matthys, Erin; Zahir, Amir; Ehrlich, Alison

    2014-01-01

    Foot dermatitis is a widespread condition, affecting men and women of all ages. Because of the location, this condition may present as a debilitating problem to those who have it. Allergic contact dermatitis involving the feet is frequently due to shoes or socks. The allergens that cause shoe dermatitis can be found in any constituent of footwear, including rubber, adhesives, leather, dyes, metals, and medicaments. The goal of treatment is to identify and minimize contact with the offending allergen(s). The lack of product information released from shoe manufacturers and the continually changing trends in footwear present a challenge in treating this condition. The aim of this study is to review the current literature on allergic contact shoe dermatitis; clinical presentation, allergens, patch testing, and management will be discussed. PubMed and MEDLINE databases were used for the search, with a focus on literature updates from the last 15 years.

  13. ALLERGIC CONTACT DERMATITIS

    Directory of Open Access Journals (Sweden)

    Trisna Yuliharti Tersinanda

    2013-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Allergic contact dermatitis is an immunologic reaction that tends to involve the surrounding skin and may even spread beyond affected sites. This skin disease is one of the more frequent, and costly dermatologic problems. Recent data from United Kingdom and United States suggest that the percentage of occupational contact dermatitis due to allergy may be much higher, thus raising the economic impact of occupational allergic contact dermatitis. There is not enough data about the epidemiology of allergic contact dermatitis in Indonesia, however based on research that include beautician in Denpasar, about 27,6 percent had side effect of cosmetics, which is 25,4 percent of it manifested as allergic contact dermatitis. Diagnosis of allergic contact dermatitis is based on anamnesis, physical examination, patch test, and this disease should be distinguished from other eczematous skin disease. The management is prevention of allergen exposure, symptomatic treatment, and physicochemical barrier /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  14. Implications of TGFβ on transcriptome and cellular biofunctions of palatal mesenchyme

    Directory of Open Access Journals (Sweden)

    Xiujuan eZhu

    2012-04-01

    Full Text Available Development of the palate comprises sequential stages of growth, elevation and fusion of the palatal shelves. The mesenchymal component of palates plays a major role in early phases of palatogenesis, such as growth and elevation. Failure in these steps may result in cleft palate, the second most common birth defect in the world. These early stages of palatogenesis require precise and chronological orchestration of key physiological processes, such as growth, proliferation, differentiation, migration, and apoptosis. There is compelling evidence for the vital role of TGFβ-mediated regulation of palate development. We hypothesized that the isoforms of TGFβ regulate different cellular biofunctions of the palatal mesenchyme to various extents. Human embryonic palatal mesenchyme (HEPM cells were treated with TGFβ1, β2, and β3 for microarray-based gene expression studies in order to identify the roles of TGFβ in the transcriptome of the palatal mesenchyme. Following normalization and modeling of 28,869 human genes, 566 transcripts were detected as differentially expressed in TGFβ-treated HEPM cells. Out of these altered transcripts, 234 of them were clustered in cellular biofunctions, including growth and proliferation, development, morphology, movement, cell cycle, and apoptosis. Biological interpretation and network analysis of the genes active in cellular biofunctions were performed using IPA. Among the differentially expressed genes, 11 of them were previously identified as being crucial for palatogenesis (EDN1, INHBA, LHX8, PDGFC, PIGA, RUNX1, SNAI1, SMAD3, TGFβ1, TGFβ2, and TGFβR1. These genes were used for a merged interaction network with cellular behaviors. Overall, we have determined that more than 2% of human transcripts were differentially expressed in response to TGFβ treatment in HEPM cells. Our results suggest that both TGFβ1 and TGFβ2 orchestrate major cellular biofunctions within the palatal mesenchyme in vitro by

  15. Mesenchymal Stem Cells after Polytrauma: Actor and Target

    Directory of Open Access Journals (Sweden)

    Markus Huber-Lang

    2016-01-01

    Full Text Available Mesenchymal stem cells (MSCs are multipotent cells that are considered indispensable in regeneration processes after tissue trauma. MSCs are recruited to damaged areas via several chemoattractant pathways where they function as “actors” in the healing process by the secretion of manifold pro- and anti-inflammatory, antimicrobial, pro- and anticoagulatory, and trophic/angiogenic factors, but also by proliferation and differentiation into the required cells. On the other hand, MSCs represent “targets” during the pathophysiological conditions after severe trauma, when excessively generated inflammatory mediators, complement activation factors, and damage- and pathogen-associated molecular patterns challenge MSCs and alter their functionality. This in turn leads to complement opsonization, lysis, clearance by macrophages, and reduced migratory and regenerative abilities which culminate in impaired tissue repair. We summarize relevant cellular and signaling mechanisms and provide an up-to-date overview about promising future therapeutic MSC strategies in the context of severe tissue trauma.

  16. Characterization and Application of a Disposable Rotating BedBioreactor for Mesenchymal Stem Cell Expansion

    OpenAIRE

    Neumann, Anne; Lavrentieva, Antonina; Heilkenbrinker, Alexandra; Loenne, Maren; Kasper, Cornelia

    2014-01-01

    Recruitment of mesenchymal stromal cells (MSC) into the field of tissue engineering is a promising development since these cells can be expanded vivo to clinically relevant numbers and, after expansion, retain their ability to differentiate into various cell lineages. Safety requirements and the necessity to obtain high cell numbers without frequent subcultivation of cells raised the question of the possibility of expanding MSC in one-way (single-use) disposable bioreactors. In this study, u...

  17. Mesenchymal stem cells display different gene expression profiles compared to hyaline and elastic chondrocytes

    OpenAIRE

    Zhai, Li-Jie; Zhao, Ke-Qing; Wang, Zhi-Qiang; Feng, Ya; Xing, Shuang-Chun

    2011-01-01

    Cartilage has a poor intrinsic repair capacity, requiring surgical intervention to effect biological repair. Tissue engineering technologies or regenerative medicine strategies are currently being employed to address cartilage repair. Mesenchymal stem cells (MSCs) are considered to be an excellent cell source for this application. However, the different gene expression profiles between the MSCs and differentiated cartilage remain unclear. In this report, we first examined the gene expression ...

  18. Mesenchymal change and drug resistance in neuroblastoma.

    Science.gov (United States)

    Naiditch, Jessica A; Jie, Chunfa; Lautz, Timothy B; Yu, Songtao; Clark, Sandra; Voronov, Dimitry; Chu, Fei; Madonna, Mary Beth

    2015-01-01

    Metastatic initiation has many phenotypic similarities to epithelial-to-mesenchymal transition, including loss of cell-cell adhesion, increased invasiveness, and increased cell mobility. We have previously demonstrated that drug resistance is associated with a metastatic phenotype in neuroblastoma (NB). The purpose of this project was to determine if the development of doxorubicin resistance is associated with characteristics of mesenchymal change in human NB cells. Total RNA was isolated from wild type (WT) and doxorubicin-resistant (DoxR) human NB cell lines (SK-N-SH and SK-N-BE(2)C) and analyzed using the Illumina Human HT-12 version 4 Expression BeadChip. Differentially expressed genes (DEGs) were identified. Volcano plots and heat maps were generated. Genes of interest with a fold change in expression >1.5 and an adjusted P change via multiple pathways in the transition to a drug-resistant state. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Ultrastructural and immunocytochemical analysis of multilineage differentiated human dental pulp- and umbilical cord-derived mesenchymal stem cells

    NARCIS (Netherlands)

    Struys, T.; Moreels, M.; Martens, W.; Donders, R.; Wolfs, E.; Lambrichts, I.

    2011-01-01

    Mesenchymal stem cells (MSCs) are one of the most promising stem cell types due to their availability and relatively simple requirements for in vitro expansion and genetic manipulation. Besides the well-characterized MSCs derived from bone marrow, there is growing evidence suggesting that dental

  20. The role of the mesenchyme in cranial neural fold elevation

    International Nuclear Information System (INIS)

    Morris-Wiman, J.A.

    1988-01-01

    It has been previously postulated that the expansion of an hyaluronate-rich extracellular matrix in the fold mesenchyme is responsible for neural fold elevation. In this study we provide evidence that such expansions may play an important role in cranial neural fold elevation by pushing the folds towards the dorsal midline to assist in their elevation. For mesenchymal expansion to result in fold elevation, hyaluronate (HA) and mesenchymal cells must be non-randomly distributed within the mesenchyme. Patterns of mesenchymal cell distribution and cell proliferation were analyzed using the computer-assisted method of smoothed spatial averaging. The distribution of Alcian blue-stained and 3 H-glucosamine-labelled HA was also analyzed during cranial neural fold elevation using established image processing techniques. Analysis of the distribution of 3 H-thymidine-labelled mesenchymal cells indicated that differential mitotic activity was not responsible for decreased mesenchymal cell density. Likewise, analysis of distribution patterns of 3 H-glucosamine-labelled HA indicated that decreased HA concentration was not produced by regional differences in HA synthesis. These results suggest that decreases in mesenchymal cell density and HA concentration that occur during neural fold elevation are produced by mesenchymal expansion

  1. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Spanish . Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American ...

  2. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / News Halloween Hazard: The Hidden Dangers ... Decorative Contact Lenses Without a Prescription Leer en Español: Peligros asociados con los lentes de contacto de ...

  3. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... prescription. There is no such thing as a "one size fits all" contact lens. Lenses that are not properly fitted may scratch the eye or cause blood vessels to grow into the cornea. Even if you have perfect vision, you need to get an eye exam and a prescription ...

  4. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... MD, professor of ophthalmology at Case Western Reserve University in Cleveland. "This is far from the truth." ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering buying approved by the ... Service For Advertisers For Media Ophthalmology Job Center © American ...

  5. Fermilab | Contact Fermilab

    Science.gov (United States)

    Education Safety Sustainability and Environment Contact Related Links DOE FRA UChicago URA Newsroom -840-3000 Fax: 630-840-4343 Shipping address Fermilab Receiving Wilson Street and Kirk Road Batavia IL 60510-5011 Phone: 630-840-3000 Visiting address Fermilab entrance Kirk Road and Pine Street Batavia IL

  6. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Español Eye Health / News Halloween Hazard: The Hidden Dangers of Buying Decorative Contact Lenses Without a Prescription ... be purchased over-the-counter or on the Internet," says Thomas Steinemann, MD, professor of ophthalmology at ...

  7. Lettuce contact allergy

    DEFF Research Database (Denmark)

    Paulsen, Evy; Andersen, Klaus E

    2016-01-01

    Lettuce (Lactuca sativa L.) and its varieties are important vegetable crops worldwide. They are also well-known, rarely reported, causes of contact allergy. As lettuce allergens and extracts are not commercially available, the allergy may be underdiagnosed. The aims of this article are to present...... person who is occupationally exposed to lettuce for longer periods, especially atopics, amateur gardeners, and persons keeping lettuce-eating pets, is potentially at risk of developing lettuce contact allergy.......Lettuce (Lactuca sativa L.) and its varieties are important vegetable crops worldwide. They are also well-known, rarely reported, causes of contact allergy. As lettuce allergens and extracts are not commercially available, the allergy may be underdiagnosed. The aims of this article are to present...... new data on lettuce contact allergy and review the literature. Lettuce is weakly allergenic, and occupational cases are mainly reported. Using aimed patch testing in Compositae-allergic patients, two recent Danish studies showed prevalence rates of positive lettuce reactions of 11% and 22...

  8. Contact allergy to spices

    NARCIS (Netherlands)

    W. Van den Akker Th. (W.); I.D. Roesyanto-Mahadi (I.); A.W. van Toorenenbergen (Albert); Th. van Joost (Theo)

    1990-01-01

    textabstractA group of 103 patients suspected of contact allergy was tested with the European standard series, wood tars and spices; paprika, cinnamon, laurel, celery seed, nutmeg, curry, black pepper, cloves, while pepper, coriander, cacao and garlic. 32 patients (Group I) were selected on the

  9. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... A medical degree and many more years of training, for starters. A recent article from U.S. News and World Report explains what ophthalmologists are and how they can help you look after ... Contact Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical ...

  10. Mathematics Connection: Contact

    African Journals Online (AJOL)

    Principal Contact. Dr. Kofi Mereku Executive Editor Department of Mathematics Education, UCE Mathematical Association of Ghana, C/o Department of Mathematics Education University College of Education of Winneba P. O. Box 25, Winneba, Ghana Phone: +233244961318. Email: dkmereku@uew.edu.gh ...

  11. Contact activation: a revision.

    Science.gov (United States)

    Schmaier, A H

    1997-07-01

    In conclusion, a revised view of the contact system has been presented. This system has little to do with the initiation of hemostasis. Like lupus anticoagulants, deficiencies of contact proteins give prolonged APTTs but may be risk factors for thrombosis. BK from kininogens is a potent modulator of vascular biology inducing vasodilation, tissue plasminogen activator release, and prostacyclin liberation. Kininogens, themselves, are selective inhibitors of alpha-thrombin-induced platelet activation preventing alpha-thrombin from cleaving the cloned thrombin receptor after arginine41. Kininogens' alpha-thrombin inhibitory activity exists in intact kininogens, BK, and all of BK's breakdown products. HK also is the pivotal protein for contact protein assembly on endothelium. It is the receptor for prekallikrein which when bound to HK becomes activated to kallikrein by an endothelial cell enzyme system independent of activated forms of plasma factor XII. Prekallikrein activation on endothelial cells results in kinetically favorable single chain urokinase and plasminogen activation. Thus the "physiologic, negatively charged surface" for contact system activation is really the assembly of these proteins on cell membranes and activation by membrane-associated enzymes.

  12. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... wear any kind of contact lens. In Butler's case, the lenses caused an infection and left her with a corneal ... A recent article from U.S. News and World Report explains what ophthalmologists are and how they can ...

  13. Language Contact and Bilingualism

    NARCIS (Netherlands)

    Appel, René; Muysken, Pieter

    2006-01-01

    What happens - sociologically, linguistically, educationally, politically - when more than one language is in regular use in a community? How do speakers handle these languages simultaneously, and what influence does this language contact have on the languages involved? Although most people in the

  14. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... Health / News Halloween Hazard: The Hidden Dangers of Buying Decorative Contact Lenses Without a Prescription Leer en Español: Peligros asociados con los lentes de contacto de color Sep. 26, 2013 It started as an impulsive buy from a souvenir shop, but 10 hours ...

  15. Pizza makers' contact dermatitis.

    Science.gov (United States)

    Lembo, Serena; Lembo, Claudio; Patruno, Cataldo; Balato, Anna; Balato, Nicola; Ayala, Fabio

    2014-01-01

    Contact eczema to foods, spices, and food additives can occur in occupational and nonoccupational settings in those who grow, handle, prepare, or cook food. Pizza is one of the most eaten foods in every continent, and pizza making is a common work in many countries. We aimed to evaluate the occurrence and the causes of contact dermatitis in pizza makers in Naples. We performed an observational study in 45 pizza makers: all the enrolled subjects had to answer a questionnaire designed to detect personal history of respiratory or cutaneous allergy, atopy; work characteristics and timing were also investigated. Every subject attended the dermatology clinic for a complete skin examination, and when needed, patients were patch tested using the Italian baseline series of haptens integrated with an arbitrary pizza makers series. Our results reported that 13.3% of the enrolled pizza makers (6/45) presented hand eczema, and that 8.9% (4/45) were affected by occupational allergic contact dermatitis. Diallyl disulfide and ammonium persulfate were the responsible substances. Performing patch tests in pizza makers and food handlers affected by hand contact dermatitis is useful. We propose a specific series of haptens for this wide working category.

  16. Contact: Releasing the news

    Science.gov (United States)

    Pinotti, Roberto

    The problem of mass behavior after man's future contacts with other intelligences in the universe is not only a challenge for social scientists and political leaders all over the world, but also a cultural time bomb as well. In fact, since the impact of CETI (Contact with Extraterrestrial Intelligence) on human civilization, with its different cultures, might cause a serious socio-anthropological shock, a common and predetermined worldwide strategy is necessary in releasing the news after the contact, in order to keep possible manifestations of fear, panic and hysteria under control. An analysis of past studies in this field and of parallel historical situations as analogs suggests a definite "authority crisis" in the public as a direct consequence of an unexpected release of the news, involving a devastating "chain reaction" process (from both the psychological and sociological viewpoints) of anomie and maybe the collapse of today's society. The only way to prevent all this is to prepare the world's public opinion concerning contact before releasing the news, and to develop a long-term strategy through the combined efforts of scientists, political leaders, intelligence agencies and the mass media, in order to create the cultural conditions in which a confrontation with ETI won't affect mankind in a traumatic way. Definite roles and tasks in this multi-level model are suggested.

  17. Rigid Bodies in Contact

    DEFF Research Database (Denmark)

    Niebe, Sarah Maria

    . A contact point determination method, based on boolean surface maps, is developed to handle collisions between tetrahedral meshes. The novel nonsmooth nonlinear conjugate gradient (NNCG) method is presented. The NNCG method is comparable in terms of accuracy to the state-of-the-art method, projected Gauss...

  18. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... can be purchased over-the-counter or on the Internet," says Thomas Steinemann, MD, professor of ophthalmology at ... ask for a prescription. There is no such thing as a "one size fits all" contact lens. Lenses that are not properly fitted may scratch the eye or cause blood vessels to grow into ...

  19. Contact allergy to cosmetics

    DEFF Research Database (Denmark)

    Held, E; Johansen, J D; Agner, T

    1999-01-01

    In a 2-year period, 1527 patients with contact dermatitis were investigated in the patch-test clinic. In 531 patients, allergy to cosmetics was suspected from the history and they were tested with their own cosmetic products. 40 (7.5%) (of the 531 patients) had 1 or more positive reactions, 82 (15...

  20. Ghana Mining Journal: Contact

    African Journals Online (AJOL)

    Principal Contact. Professor Daniel Mireku-Gyimah Editor-in-Chief University of Mines & Technology Ghana Mining Journal University of Mines & Technology P. O. BOX 237 Tarkwa Ghana Phone: +233 362 20280/20324. Fax: +233 362 20306. Email: dm.gyimah@umat.edu.gh ...

  1. Mesenchymal neoplasia and congenital pulmonary cysts

    International Nuclear Information System (INIS)

    Weinberg, A.G.; Currarino, G.; Moore, G.C.; Votteler, T.P.

    1980-01-01

    A malignant mesenchymoma exibiting a varied spectrum of differentation developed within a congenital pulmonary cyst 6 1/2 years after the cyst was first recognized. Related tumors with a similar gross appearance have been previously described and have included rhabdomyosarcomas and so-called pulmonary blastomas. There is a low but distinct risk for the developement of mesenchymal sarcomas within congenital peripheral pulmonary cysts. (orig.) [de

  2. Mesenchymal stem cell-educated macrophages

    OpenAIRE

    Eggenhofer Elke; Hoogduijn Martin J

    2012-01-01

    Abstract Mesenchymal stem cells (MSC) mediate their immunosuppressive effects via a variety of mechanisms. One of these mechanisms involves the induction of macrophages with immunomodulatory capacities. This effect of MSC may be exploited when MSC are used as a cell therapeutic product. Furthermore, MSC are resident in tissues where they may locally target infiltrating macrophages to adapt more regulatory properties. The present review discusses the interaction between MSC and macrophages, th...

  3. Mesenchymal Stem Cells: Angels or Demons?

    OpenAIRE

    Wong, Rebecca S. Y.

    2011-01-01

    Mesenchymal stem cells (MSCs) have been used in cell-based therapy in various disease conditions such as graft-versus-host and heart diseases, osteogenesis imperfecta, and spinal cord injuries, and the results have been encouraging. However, as MSC therapy gains popularity among practitioners and researchers, there have been reports on the adverse effects of MSCs especially in the context of tumour modulation and malignant transformation. These cells have been found to enhance tumour growth a...

  4. Living labeling techniques of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Dong Qingyu; Chen Li

    2007-01-01

    Mesenchymal stem cells (MSCs) are well known for their self-renew and multi- differentiation potentiality. With the transplantation of the MSCs which can promote the regeneration and repair of the injured tissue, a new route for the treatment of dieases is hopeful to be effective. To trace the distribution, migration, proliferation and differentiation of the implanted MSCs, there need effective labeling techniques, especially living labeling techniques. (authors)

  5. Molecular dynamics study of contact mechanics: contact area and interfacial separation from small to full contact

    OpenAIRE

    Yang, C.; Persson, B. N. J.

    2007-01-01

    We report a molecular dynamics study of the contact between a rigid solid with a randomly rough surface and an elastic block with a flat surface. We study the contact area and the interfacial separation from small contact (low load) to full contact (high load). For small load the contact area varies linearly with the load and the interfacial separation depends logarithmically on the load. For high load the contact area approaches to the nominal contact area (i.e., complete contact), and the i...

  6. Guidance of mesenchymal stem cells on fibronectin structured hydrogel films.

    Directory of Open Access Journals (Sweden)

    Annika Kasten

    Full Text Available Designing of implant surfaces using a suitable ligand for cell adhesion to stimulate specific biological responses of stem cells will boost the application of regenerative implants. For example, materials that facilitate rapid and guided migration of stem cells would promote tissue regeneration. When seeded on fibronectin (FN that was homogeneously immmobilized to NCO-sP(EO-stat-PO, which otherwise prevents protein binding and cell adhesion, human mesenchymal stem cells (MSC revealed a faster migration, increased spreading and a more rapid organization of different cellular components for cell adhesion on fibronectin than on a glass surface. To further explore, how a structural organization of FN controls the behavior of MSC, adhesive lines of FN with varying width between 10 µm and 80 µm and spacings between 5 µm and 20 µm that did not allow cell adhesion were generated. In dependance on both line width and gaps, cells formed adjacent cell contacts, were individually organized in lines, or bridged the lines. With decreasing sizes of FN lines, speed and directionality of cell migration increased, which correlated with organization of the actin cytoskeleton, size and shape of the nuclei as well as of focal adhesions. Together, defined FN lines and gaps enabled a fine tuning of the structural organization of cellular components and migration. Microstructured adhesive substrates can mimic the extracellular matrix in vivo and stimulate cellular mechanisms which play a role in tissue regeneration.

  7. Mesenchymal dental stem cells in regenerative dentistry.

    Science.gov (United States)

    Rodríguez-Lozano, Francisco-Javier; Insausti, Carmen-Luisa; Iniesta, Francisca; Blanquer, Miguel; Ramírez, María-del-Carmen; Meseguer, Luis; Meseguer-Henarejos, Ana-Belén; Marín, Noemí; Martínez, Salvador; Moraleda, José-María

    2012-11-01

    In the last decade, tissue engineering is a field that has been suffering an enormous expansion in the regenerative medicine and dentistry. The use of cells as mesenchymal dental stem cells of easy access for dentist and oral surgeon, immunosuppressive properties, high proliferation and capacity to differentiate into odontoblasts, cementoblasts, osteoblasts and other cells implicated in the teeth, suppose a good perspective of future in the clinical dentistry. However, is necessary advance in the known of growth factors and signalling molecules implicated in tooth development and regeneration of different structures of teeth. Furthermore, these cells need a fabulous scaffold that facility their integration, differentiation, matrix synthesis and promote multiple specific interactions between cells. In this review, we give a brief description of tooth development and anatomy, definition and classification of stem cells, with special attention of mesenchymal stem cells, commonly used in the cellular therapy for their trasdifferentiation ability, non ethical problems and acceptable results in preliminary clinical trials. In terms of tissue engineering, we provide an overview of different types of mesenchymal stem cells that have been isolated from teeth, including dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHEDs), periodontal ligament stem cells (PDLSCs), dental follicle progenitor stem cells (DFPCs), and stem cells from apical papilla (SCAPs), growth factors implicated in regeneration teeth and types of scaffolds for dental tissue regeneration.

  8. Creb1 regulates late stage mammalian lung development via respiratory epithelial and mesenchymal-independent mechanisms

    Science.gov (United States)

    Antony, N.; McDougall, A. R.; Mantamadiotis, T.; Cole, T. J.; Bird, A. D.

    2016-01-01

    During mammalian lung development, the morphological transition from respiratory tree branching morphogenesis to a predominantly saccular architecture, capable of air-breathing at birth, is dependent on physical forces as well as molecular signaling by a range of transcription factors including the cAMP response element binding protein 1 (Creb1). Creb1−/− mutant mice exhibit complete neonatal lethality consistent with a lack of lung maturation beyond the branching phase. To further define its role in the developing mouse lung, we deleted Creb1 separately in the respiratory epithelium and mesenchyme. Surprisingly, we found no evidence of a morphological lung defect nor compromised neonatal survival in either conditional Creb1 mutant. Interestingly however, loss of mesenchymal Creb1 on a genetic background lacking the related Crem protein showed normal lung development but poor neonatal survival. To investigate the underlying requirement for Creb1 for normal lung development, Creb1−/− mice were re-examined for defects in both respiratory muscles and glucocorticoid hormone signaling, which are also required for late stage lung maturation. However, these systems appeared normal in Creb1−/− mice. Together our results suggest that the requirement of Creb1 for normal mammalian lung morphogenesis is not dependent upon its expression in lung epithelium or mesenchyme, nor its role in musculoskeletal development. PMID:27150575

  9. Moving contact lines on vibrating surfaces

    Science.gov (United States)

    Solomenko, Zlatko; Spelt, Peter; Scott, Julian

    2017-11-01

    Large-scale simulations of flows with moving contact lines for realistic conditions generally requires a subgrid scale model (analyses based on matched asymptotics) to account for the unresolved part of the flow, given the large range of length scales involved near contact lines. Existing models for the interface shape in the contact-line region are primarily for steady flows on homogeneous substrates, with encouraging results in 3D simulations. Introduction of complexities would require further investigation of the contact-line region, however. Here we study flows with moving contact lines on planar substrates subject to vibrations, with applications in controlling wetting/dewetting. The challenge here is to determine the change in interface shape near contact lines due to vibrations. To develop further insight, 2D direct numerical simulations (wherein the flow is resolved down to an imposed slip length) have been performed to enable comparison with asymptotic theory, which is also developed further. Perspectives will also be presented on the final objective of the work, which is to develop a subgrid scale model that can be utilized in large-scale simulations. The authors gratefully acknowledge the ANR for financial support (ANR-15-CE08-0031) and the meso-centre FLMSN for use of computational resources. This work was Granted access to the HPC resources of CINES under the allocation A0012B06893 made by GENCI.

  10. Human mesenchymal stem cells inhibit osteoclastogenesis through osteoprotegerin production.

    Science.gov (United States)

    Oshita, Koichi; Yamaoka, Kunihiro; Udagawa, Nobuyuki; Fukuyo, Shunsuke; Sonomoto, Koshiro; Maeshima, Keisuke; Kurihara, Ryuji; Nakano, Kazuhisa; Saito, Kazuyoshi; Okada, Yosuke; Chiba, Kenji; Tanaka, Yoshiya

    2011-06-01

    Mesenchymal stem cells (MSCs) have been proposed to be a useful tool for treatment of rheumatoid arthritis (RA), not only because of their multipotency but also because of their immunosuppressive effect on lymphocytes, dendritic cells, and other proinflammatory cells. Since bone destruction caused by activated osteoclasts occurs in RA, we undertook the present study to investigate the effect of MSCs on osteoclast function and differentiation in order to evaluate their potential use in RA therapy. Human MSCs and peripheral blood mononuclear cells were cultured under cell-cell contact-free conditions with osteoclast induction medium. Differentiation into osteoclast-like cells was determined by tartrate-resistant acid phosphatase staining and expression of osteoclast differentiation markers. The number of osteoclast-like cells was decreased and expression of cathepsin K and nuclear factor of activated T cells c1 (NF-ATc1) was down-regulated by the addition of either MSCs or a conditioned medium obtained from MSCs. Osteoprotegerin (OPG) was constitutively produced by MSCs and inhibited osteoclastogenesis. However, osteoclast differentiation was not fully recovered upon treatment with either anti-OPG antibody or OPG small interfering RNA, suggesting that OPG had only a partial role in the inhibitory effect of MSCs. Moreover, bone-resorbing activity of osteoclast-like cells was partially recovered by addition of anti-OPG antibody into the conditioned medium. The present results indicate that human MSCs constitutively produce OPG, resulting in inhibition of osteoclastogenesis and expression of NF-ATc1 and cathepsin K in the absence of cell-cell contact. Therefore, we conclude that human MSCs exert a suppressive effect on osteoclastogenesis, which may be beneficial in inhibition of joint damage in RA. Copyright © 2011 by the American College of Rheumatology.

  11. Focusing on Contact Lens Safety

    Science.gov (United States)

    ... their practices. Decorative contacts (also called “costume,” colored,” “fashion,” or “plano” contacts). The FDA has often warned ... Lenses Decorative Contact Lenses Hydrogen Peroxide Solution Related Consumer Updates 'Colored' and Decorative Contact Lenses: A Prescription ...

  12. Electrical contacts principles and applications

    CERN Document Server

    Slade, Paul G

    2013-01-01

    Covering the theory, application, and testing of contact materials, Electrical Contacts: Principles and Applications, Second Edition introduces a thorough discussion on making electric contact and contact interface conduction; presents a general outline of, and measurement techniques for, important corrosion mechanisms; considers the results of contact wear when plug-in connections are made and broken; investigates the effect of thin noble metal plating on electronic connections; and relates crucial considerations for making high- and low-power contact joints. It examines contact use in switch

  13. [News on occupational contact dermatitis].

    Science.gov (United States)

    Crépy, Marie-Noëlle; Bensefa-Colas, Lynda

    2014-03-01

    Contact dermatitis--irritant contact dermatitis, allergic contact dermatitis and protein contact dermatitis--are the most common occupational skin diseases, most often localized to the hands. Contact urticaria is rarer The main occupational irritants are wet work, detergents and disinfectants, cutting oils, and solvents. The main occupational allergens are rubber additives, metals (chromium, nickel, cobalt), plastics (epoxy resins, acrylic), biocides and plants. Diagnosis is based on clinical examination, medical history and allergy testing. For a number of irritating or sensitizing agents, irritant or allergic dermatitis can be notified as occupational diseases. The two main prevention measures are reducing skin contact with irritants and complete avoidance of skin contact with offending allergens.

  14. The regulation of tooth morphogenesis is associated with epithelial cell proliferation and the expression of Sonic hedgehog through epithelial-mesenchymal interactions

    International Nuclear Information System (INIS)

    Ishida, Kentaro; Murofushi, Mayumi; Nakao, Kazuhisa; Morita, Ritsuko; Ogawa, Miho; Tsuji, Takashi

    2011-01-01

    Research highlights: → Bioengineered teeth regulated the contact area of epithelium and mesenchyme. → The crown width is regulated by the contact area of the epithelium and mesenchyme. → This regulation is associated with cell proliferation and Sonic hedgehog expression. → The cusp number is correlated with the crown width of the bioengineered tooth. → Cell proliferation and Shh expression areas regulate the tooth morphogenesis. -- Abstract: Ectodermal organs, such as the tooth, salivary gland, hair, and mammary gland, develop through reciprocal epithelial-mesenchymal interactions. Tooth morphologies are defined by the crown width and tooth length (macro-morphologies), and by the number and locations of the cusp and roots (micro-morphologies). In our current study, we report that the crown width of a bioengineered molar tooth, which was reconstructed using dissociated epithelial and mesenchymal cells via an organ germ method, can be regulated by the contact area between epithelial and mesenchymal cell layers. We further show that this is associated with cell proliferation and Sonic hedgehog (Shh) expression in the inner enamel epithelium after the germ stage has formed a secondary enamel knot. We also demonstrate that the cusp number is significantly correlated with the crown width of the bioengineered tooth. These findings suggest that the tooth micro-morphology, i.e. the cusp formation, is regulated after the tooth width, or macro-morphology, is determined. These findings also suggest that the spatiotemporal patterning of cell proliferation and the Shh expression areas in the epithelium regulate the crown width and cusp formation of the developing tooth.

  15. Effects of PPARγ ligands on TGF-β1-induced epithelial-mesenchymal transition in alveolar epithelial cells

    Directory of Open Access Journals (Sweden)

    Dagher Hayat

    2010-02-01

    Full Text Available Abstract Background Transforming growth factor β1 (TGF-β1-mediated epithelial mesenchymal transition (EMT of alveolar epithelial cells (AEC may contribute to lung fibrosis. Since PPARγ ligands have been shown to inhibit fibroblast activation by TGF-β1, we assessed the ability of the thiazolidinediones rosiglitazone (RGZ and ciglitazone (CGZ to regulate TGF-β1-mediated EMT of A549 cells, assessing changes in cell morphology, and expression of cell adhesion molecules E-cadherin (epithelial cell marker and N-cadherin (mesenchymal cell marker, and collagen 1α1 (COL1A1, CTGF and MMP-2 mRNA. Methods Serum-deprived A549 cells (human AEC cell line were pre-incubated with RGZ and CGZ (1 - 30 μM in the absence or presence of the PPARγ antagonist GW9662 (10 μM before TGFβ-1 (0.075-7.5 ng/ml treatment for up to 72 hrs. Changes in E-cadherin, N-cadherin and phosphorylated Smad2 and Smad3 levels were analysed by Western blot, and changes in mRNA levels including COL1A1 assessed by RT-PCR. Results TGFβ-1 (2.5 ng/ml-induced reductions in E-cadherin expression were associated with a loss of epithelial morphology and cell-cell contact. Concomitant increases in N-cadherin, MMP-2, CTGF and COL1A1 were evident in predominantly elongated fibroblast-like cells. Neither RGZ nor CGZ prevented TGFβ1-induced changes in cell morphology, and PPARγ-dependent inhibitory effects of both ligands on changes in E-cadherin were only evident at submaximal TGF-β1 (0.25 ng/ml. However, both RGZ and CGZ inhibited the marked elevation of N-cadherin and COL1A1 induced by TGF-β1 (2.5 ng/ml, with effects on COL1A1 prevented by GW9662. Phosphorylation of Smad2 and Smad3 by TGF-β1 was not inhibited by RGZ or CGZ. Conclusions RGZ and CGZ inhibited profibrotic changes in TGF-β1-stimulated A549 cells independently of inhibition of Smad phosphorylation. Their inhibitory effects on changes in collagen I and E-cadherin, but not N-cadherin or CTGF, appeared to be PPAR

  16. HTSC-Josephson step contacts

    International Nuclear Information System (INIS)

    Herrmann, K.

    1994-03-01

    In this work the properties of josephson step contacts are investigated. After a short introduction into Josephson step contacts the structure, properties and the Josphson contacts of YBa 2 Cu 3 O 7-x high-T c superconductors is presented. The fabrication of HTSC step contacts and the microstructure is discussed. The electric properties of these contacts are measured together with the Josephson emission and the magnetic field dependence. The temperature dependence of the stationary transport properties is given. (WL)

  17. Contact dynamics math model

    Science.gov (United States)

    Glaese, John R.; Tobbe, Patrick A.

    1986-01-01

    The Space Station Mechanism Test Bed consists of a hydraulically driven, computer controlled six degree of freedom (DOF) motion system with which docking, berthing, and other mechanisms can be evaluated. Measured contact forces and moments are provided to the simulation host computer to enable representation of orbital contact dynamics. This report describes the development of a generalized math model which represents the relative motion between two rigid orbiting vehicles. The model allows motion in six DOF for each body, with no vehicle size limitation. The rotational and translational equations of motion are derived. The method used to transform the forces and moments from the sensor location to the vehicles' centers of mass is also explained. Two math models of docking mechanisms, a simple translational spring and the Remote Manipulator System end effector, are presented along with simulation results. The translational spring model is used in an attempt to verify the simulation with compensated hardware in the loop results.

  18. Contact allergy to lanolin

    DEFF Research Database (Denmark)

    Fransen, Marloes; Overgaard, Line E K; Johansen, Jeanne D

    2018-01-01

    BACKGROUND: Lanolin has been tested as lanolin alcohols (30% pet.) in baseline patch test series since 1969, and this has shown clinically relevant allergic contact dermatitis cases. OBJECTIVES: To investigate the temporal development of lanolin allergy (i.e. positive reaction to lanolin alcohols...... and/or Amerchol™ L-101), and the association between contact allergy to lanolin and patient characteristics from the MOAHLFA index. METHODS: A retrospective observational study of consecutively patch tested dermatitis patients (n = 9577) between 1 January 2004 and 31 December 2015 with lanolin...... alcohols 30% pet. and Amerchol™ L-101 50% pet. was performed. RESULTS: The prevalence of lanolin allergy increased from 0.45% in 2004 to 1.81% in 2015. In age-adjusted and sex-adjusted analyses, weak, significant associations were found between atopic dermatitis and lanolin and lanolin alcohols allergy...

  19. Contact stress sensor

    Science.gov (United States)

    Kotovsky, Jack [Oakland, CA

    2012-02-07

    A contact stress sensor includes one or more MEMS fabricated sensor elements, where each sensor element of includes a thin non-recessed portion, a recessed portion and a pressure sensitive element adjacent to the recessed portion. An electric circuit is connected to the pressure sensitive element. The circuit includes a thermal compensator and a pressure signal circuit element configured to provide a signal upon movement of the pressure sensitive element.

  20. Fragrance contact allergy

    DEFF Research Database (Denmark)

    Johansen, Jeanne D

    2003-01-01

    . This gives a positive patch-test reaction in about 10% of tested patients with eczema, and the most recent estimates show that 1.7-4.1% of the general population are sensitized to ingredients of the fragrance mix. Fragrance allergy occurs predominantly in women with facial or hand eczema. These women...... development to identify contact allergy to new allergens, reflecting the continuous developments and trends in exposure....

  1. Pediatric contact dermatitis

    Directory of Open Access Journals (Sweden)

    Sharma Vinod

    2010-01-01

    Full Text Available Allergic contact dermatitis (ACD in children, until recently, was considered rare. ACD was considered as a disorder of the adult population and children were thought to be spared due to a lack of exposure to potential allergens and an immature immune system. Prevalence of ACD to even the most common allergens in children, like poison ivy and parthenium, is relatively rare as compared to adults. However, there is now growing evidence of contact sensitization of the pediatric population, and it begins right from early childhood, including 1-week-old neonates. Vaccinations, piercing, topical medicaments and cosmetics in younger patients are potential exposures for sensitization. Nickel is the most common sensitizer in almost all studies pertaining to pediatric contact dermatitis. Other common allergens reported are cobalt, fragrance mix, rubber, lanolin, thiomersol, neomycin, gold, mercapto mix, balsum of Peru and colophony. Different factors like age, sex, atopy, social and cultural practices, habit of parents and caregivers and geographic changes affect the patterns of ACD and their variable clinical presentation. Patch testing should be considered not only in children with lesions of a morphology suggestive of ACD, but in any child with dermatitis that is difficult to control.

  2. JNK signaling maintains the mesenchymal properties of multi-drug resistant human epidermoid carcinoma KB cells through snail and twist1

    International Nuclear Information System (INIS)

    Zhan, Xia; Feng, Xiaobing; Kong, Ying; Chen, Yi; Tan, Wenfu

    2013-01-01

    In addition to possess cross drug resistance characteristic, emerging evidences have shown that multiple-drug resistance (MDR) cancer cells exhibit aberrant metastatic capacity when compared to parental cells. In this study, we explored the contribution of c-Jun N-terminal kinases (JNK) signaling to the mesenchymal phenotypes and the aberrant motile capacity of MDR cells utilizing a well characterized MDR cell line KB/VCR, which is established from KB human epidermoid carcinoma cells by vincristine (VCR), and its parental cell line KB. Taking advantage of experimental strategies including pharmacological tool and gene knockdown, we showed here that interference with JNK signaling pathway by targeting JNK1/2 or c-Jun reversed the mesenchymal properties of KB/VCR cells to epithelial phenotypes and suppressed the motile capacity of KB/VCR cells, such as migration and invasion. These observations support a critical role of JNK signaling in maintaining the mesenchymal properties of KB/VCR cells. Furthermore, we observed that JNK signaling may control the expression of both snail and twist1 in KB/VCR cells, indicating that both snail and twist1 are involved in controlling the mesenchymal characteristics of KB/VCR cells by JNK signaling. JNK signaling is required for maintaining the mesenchymal phenotype of KB/VCR cells; and JNK signaling may maintain the mesenchymal characteristics of KB/VCR cells potentially through snail and twist1

  3. JNK signaling maintains the mesenchymal properties of multi-drug resistant human epidermoid carcinoma KB cells through snail and twist1.

    Science.gov (United States)

    Zhan, Xia; Feng, Xiaobing; Kong, Ying; Chen, Yi; Tan, Wenfu

    2013-04-04

    In addition to possess cross drug resistance characteristic, emerging evidences have shown that multiple-drug resistance (MDR) cancer cells exhibit aberrant metastatic capacity when compared to parental cells. In this study, we explored the contribution of c-Jun N-terminal kinases (JNK) signaling to the mesenchymal phenotypes and the aberrant motile capacity of MDR cells utilizing a well characterized MDR cell line KB/VCR, which is established from KB human epidermoid carcinoma cells by vincristine (VCR), and its parental cell line KB. Taking advantage of experimental strategies including pharmacological tool and gene knockdown, we showed here that interference with JNK signaling pathway by targeting JNK1/2 or c-Jun reversed the mesenchymal properties of KB/VCR cells to epithelial phenotypes and suppressed the motile capacity of KB/VCR cells, such as migration and invasion. These observations support a critical role of JNK signaling in maintaining the mesenchymal properties of KB/VCR cells. Furthermore, we observed that JNK signaling may control the expression of both snail and twist1 in KB/VCR cells, indicating that both snail and twist1 are involved in controlling the mesenchymal characteristics of KB/VCR cells by JNK signaling. JNK signaling is required for maintaining the mesenchymal phenotype of KB/VCR cells; and JNK signaling may maintain the mesenchymal characteristics of KB/VCR cells potentially through snail and twist1.

  4. Ohmic contacts to InN-based materials

    Directory of Open Access Journals (Sweden)

    Sai P. O.

    2016-10-01

    Full Text Available The key aspects of ohmic contact formation to InN-based materials were investigated. Detailed analysis of studies conducted over the past three decades, allows determining the basic principles of such contacts. The contact structure properties and optimal conditions for them are presented. Different types of metallization are considered, the advantages and disadvantages of each are determined, including the basic requirements that such contact must meet. There is emphasis on the using multilayer metallization with the barrier layers. In the case of the InAlN/GaN systems, the general approaches of forming ohmic contacts were considered.

  5. Gram negative bacteria and contact lens induced acute red eye

    Directory of Open Access Journals (Sweden)

    Sankaridurg Padmaja

    1996-01-01

    Full Text Available Two patients using hydrogel contact lenses on a daily wear schedule slept overnight with the lenses and woke up with a Contact Lens Induced Acute Red Eye (CLARE. The contact lenses recovered aseptically at the time of the event grew significant colonies of Pseudomonas aeruginosa and Aeromonas hydrophila in patient A and Pseudomonas aeruginosa and Serratia liquefaciens from patient B. Similar organisams from the contact lenses were recovered from the lens case and lens care solutions of patient B. In both the patients the condition resolved on discontinuation of lens wear. Patient compliance as a requirement for successful contact lens wear is highlighted with the illustration of these cases.

  6. Cell-based delivery of glucagon-like peptide-1 using encapsulated mesenchymal stem cells

    DEFF Research Database (Denmark)

    Wallrapp, Christine; Thoenes, Eric; Thürmer, Frank

    2013-01-01

    Glucagon-like peptide-1 (GLP-1) CellBeads are cell-based implants for the sustained local delivery of bioactive factors. They consist of GLP-1 secreting mesenchymal stem cells encapsulated in a spherically shaped immuno-isolating alginate matrix. A highly standardized and reproducible encapsulation...... and quality control is performed in compliance with good manufacturing practice and fulfils all regulatory requirements for human clinical use. GLP-1 CellBeads combine the neuro- and cardioprotective properties of both GLP-1 and mesenchymal stem cells. First promising results were obtained from preclinical...... method is described for the manufacturing of homogeneous CellBeads. Viability and sustained secretion was shown for the recombinant GLP-1 and the cell endogenous bioactive factors like vascular endothelial growth factor, neurotrophin 3 (NT-3) and glial cell line-derived neurotrophic factor. Manufacturing...

  7. Renal Extra Skeletal Mesenchymal Chondrosarcoma: A Case Report.

    Science.gov (United States)

    Salehipour, Mehdi; Hosseinzadeh, Masood; Sisakhti, Afshin Molaei; Parvin, Vahid Abdol Mohammadi; Sadraei, Amin; Adib, Ali

    2017-05-01

    Primary mesenchymal chondrosarcoma of the Kidney is an extremely rare entity and very few cases have been reported in literature. We report a 22-year-old male with a right renal mass; after radical nephrectomy, pathologic examination revealed primary extra skeletal mesenchymal chondrosarcoma.

  8. Epithelial-mesenchymal transition is associated with increased ...

    African Journals Online (AJOL)

    Yomi

    2011-12-16

    Dec 16, 2011 ... Key words: SMMC-7721, cancer stem cells, side population cells, invasion, epithelial-mesenchymal transition. INTRODUCTION. Invasion and metastasis are the most important biological ..... the metastatic phenotype of pancreatic cancer cells with- ... occludens-1 (ZO-1), and gain mesenchymal molecular.

  9. Mechanical Contact Experiments and Simulations

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Martins, P; Zhang, W.

    2011-01-01

    Mechanical contact is studied under dynamic development by means of a combined numerical and experimental investigation. The experiments are designed to allow dynamical development of non-planar contact areas with significant expansion in all three directions as the load is increased. Different....... The overall investigation serves for testing and validating the numerical implementation of the mechanical contact, which is one of the main contributions to a system intended for 3D simulation of resistance welding. Correct modelling of contact between parts to be welded, as well as contact with electrodes......, is crucial for satisfactory modelling of the resistance welding process. The resistance heating at the contact interfaces depends on both contact area and pressure, and as the contact areas develop dynamically, the presented tests are relevant for assessing the validity and accuracy of the mechanical contact...

  10. Airborne non-contact and contact broadband ultrasounds for frequency attenuation profile estimation of cementitious materials.

    Science.gov (United States)

    Gosálbez, J; Wright, W M D; Jiang, W; Carrión, A; Genovés, V; Bosch, I

    2018-08-01

    In this paper, the study of frequency-dependent ultrasonic attenuation in strongly heterogeneous cementitious materials is addressed. To accurately determine the attenuation over a wide frequency range, it is necessary to have suitable excitation techniques. We have analysed two kinds of ultrasound techniques: contact ultrasound and airborne non-contact ultrasound. The mathematical formulation for frequency-dependent attenuation has been established and it has been revealed that each technique may achieve similar results but requires specific different calibration processes. In particular, the airborne non-contact technique suffers high attenuation due to energy losses at the air-material interfaces. Thus, its bandwidth is limited to low frequencies but it does not require physical contact between transducer and specimen. In contrast, the classical contact technique can manage higher frequencies but the measurement depends on the pressure between the transducer and the specimen. Cement specimens have been tested with both techniques and frequency attenuation dependence has been estimated. Similar results were achieved at overlapping bandwidth and it has been demonstrated that the airborne non-contact ultrasound technique could be a viable alternative to the classical contact technique. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Experimental investigation on the electrical contact behavior of rolling contact connector

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Junxing; Yang, Fei, E-mail: yfei2007@mail.xjtu.edu.cn; Luo, Kaiyu; Zhu, Mingliang; Wu, Yi; Rong, Mingzhe [State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an 710049 (China)

    2015-12-15

    Rolling contact connector (RCC) is a new technology utilized in high performance electric power transfer systems with one or more rotating interfaces, such as radars, satellites, wind generators, and medical computed tomography machines. Rolling contact components are used in the RCC instead of traditional sliding contacts to transfer electrical power and/or signal. Since the requirement of the power transmission is increasing in these years, the rolling electrical contact characteristics become more and more important for the long-life design of RCC. In this paper, a typical form of RCC is presented. A series of experimental work are carried out to investigate the rolling electrical contact characteristics during its lifetime. The influence of a variety of factors on the electrical contact degradation behavior of RCC is analyzed under both vacuum and air environment. Based on the surface morphology and elemental composition changes in the contact zone, which are assessed by field emission scanning electron microscope and confocal laser scanning microscope, the mechanism of rolling electrical contact degradation is discussed.

  12. FreeContact: fast and free software for protein contact prediction from residue co-evolution.

    Science.gov (United States)

    Kaján, László; Hopf, Thomas A; Kalaš, Matúš; Marks, Debora S; Rost, Burkhard

    2014-03-26

    20 years of improved technology and growing sequences now renders residue-residue contact constraints in large protein families through correlated mutations accurate enough to drive de novo predictions of protein three-dimensional structure. The method EVfold broke new ground using mean-field Direct Coupling Analysis (EVfold-mfDCA); the method PSICOV applied a related concept by estimating a sparse inverse covariance matrix. Both methods (EVfold-mfDCA and PSICOV) are publicly available, but both require too much CPU time for interactive applications. On top, EVfold-mfDCA depends on proprietary software. Here, we present FreeContact, a fast, open source implementation of EVfold-mfDCA and PSICOV. On a test set of 140 proteins, FreeContact was almost eight times faster than PSICOV without decreasing prediction performance. The EVfold-mfDCA implementation of FreeContact was over 220 times faster than PSICOV with negligible performance decrease. EVfold-mfDCA was unavailable for testing due to its dependency on proprietary software. FreeContact is implemented as the free C++ library "libfreecontact", complete with command line tool "freecontact", as well as Perl and Python modules. All components are available as Debian packages. FreeContact supports the BioXSD format for interoperability. FreeContact provides the opportunity to compute reliable contact predictions in any environment (desktop or cloud).

  13. Follicular contact dermatitis revisited: A review emphasizing neomycin-associated follicular contact dermatitis

    Science.gov (United States)

    Cohen, Philip R

    2014-01-01

    Follicular contact dermatitis clinically presents as individual papules that include a central hair follicle. Pathologic features involve the follicle and the surrounding dermis: spongiosis and vesicle formation of the follicular epithelium associated with perifollicular and perivascular lymphocytic inflammation. Using the PubMed database, an extensive literature search was performed on follicular contact dermatitis and neomycin. Relevant papers were reviewed and the clinical and pathologic features, the associated chemicals (including a more detailed description of neomycin), the hypothesized pathogenesis, and the management of follicular contact dermatitis were described. Several agents-either as allergens or irritants-have been reported to elicit follicular contact dermatitis. Several hypotheses have been suggested for the selective involvement of the follicles in follicular contact dermatitis: patient allergenicity, characteristics of the agent, vehicle containing the agent, application of the agent, and external factors. The differential diagnosis of follicular contact dermatitis includes not only recurrent infundibulofolliculitis, but also drug eruption, mite infestation, viral infection, and dermatoses that affect hair follicles. The primary therapeutic intervention for follicular contact dermatitis is withdrawal of the causative agent; treatment with a topical corticosteroid preparation may also promote resolution of the dermatitis. In conclusion, follicular contact dermatitis may be secondary to allergens or irritants; topical antibiotics, including neomycin, may cause this condition. Several factors may account for the selective involvement of the hair follicle in this condition. Treatment of the dermatitis requires withdrawal of the associated topical agent; in addition, topical corticosteroids may be helpful to promote resolution of lesions. PMID:25516854

  14. Pancreatic stellate cells promote epithelial-mesenchymal transition in pancreatic cancer cells

    International Nuclear Information System (INIS)

    Kikuta, Kazuhiro; Masamune, Atsushi; Watanabe, Takashi; Ariga, Hiroyuki; Itoh, Hiromichi; Hamada, Shin; Satoh, Kennichi; Egawa, Shinichi; Unno, Michiaki; Shimosegawa, Tooru

    2010-01-01

    Research highlights: → Recent studies have shown that pancreatic stellate cells (PSCs) promote the progression of pancreatic cancer. → Pancreatic cancer cells co-cultured with PSCs showed loose cell contacts and scattered, fibroblast-like appearance. → PSCs decreased the expression of epithelial markers but increased that of mesenchymal markers, along with increased migration. → This study suggests epithelial-mesenchymal transition as a novel mechanism by which PSCs contribute to the aggressive behavior of pancreatic cancer cells. -- Abstract: The interaction between pancreatic cancer cells and pancreatic stellate cells (PSCs), a major profibrogenic cell type in the pancreas, is receiving increasing attention. There is accumulating evidence that PSCs promote the progression of pancreatic cancer by increasing cancer cell proliferation and invasion as well as by protecting them from radiation- and gemcitabine-induced apoptosis. Because epithelial-mesenchymal transition (EMT) plays a critical role in the progression of pancreatic cancer, we hypothesized that PSCs promote EMT in pancreatic cancer cells. Panc-1 and SUIT-2 pancreatic cancer cells were indirectly co-cultured with human PSCs isolated from patients undergoing operation for pancreatic cancer. The expression of epithelial and mesenchymal markers was examined by real-time PCR and immunofluorescent staining. The migration of pancreatic cancer cells was examined by scratch and two-chamber assays. Pancreatic cancer cells co-cultured with PSCs showed loose cell contacts and a scattered, fibroblast-like appearance. The expression of E-cadherin, cytokeratin 19, and membrane-associated β-catenin was decreased, whereas vimentin and Snail (Snai-1) expression was increased more in cancer cells co-cultured with PSCs than in mono-cultured cells. The migration of pancreatic cancer cells was increased by co-culture with PSCs. The PSC-induced decrease of E-cadherin expression was not altered by treatment with anti

  15. An elastic-plastic contact model for line contact structures

    Science.gov (United States)

    Zhu, Haibin; Zhao, Yingtao; He, Zhifeng; Zhang, Ruinan; Ma, Shaopeng

    2018-06-01

    Although numerical simulation tools are now very powerful, the development of analytical models is very important for the prediction of the mechanical behaviour of line contact structures for deeply understanding contact problems and engineering applications. For the line contact structures widely used in the engineering field, few analytical models are available for predicting the mechanical behaviour when the structures deform plastically, as the classic Hertz's theory would be invalid. Thus, the present study proposed an elastic-plastic model for line contact structures based on the understanding of the yield mechanism. A mathematical expression describing the global relationship between load history and contact width evolution of line contact structures was obtained. The proposed model was verified through an actual line contact test and a corresponding numerical simulation. The results confirmed that this model can be used to accurately predict the elastic-plastic mechanical behaviour of a line contact structure.

  16. Tooth engineering: searching for dental mesenchymal cells sources.

    Directory of Open Access Journals (Sweden)

    Laetitia eKeller

    2011-03-01

    Full Text Available The implantation of cultured re-associations between embryonic dental mesenchymal cells and epithelial cells from mouse molars at ED14 allowed making full teeth with crown, root, periodontal ligament fibers and bone. Although representing valuable tools to set up methodologies embryonic cells are not easily available. This work thus aimed to replace the embryonic cells by dental mesenchymal cell lines or cultured expanded embryonic cells, and to test their ability to mediate tooth development in vitro when re-associated with a competent dental epithelium. Histology, immunostaining and RT-PCR allowed getting complementary sets of results. Two different immortalized cell lines from ED18 dental mesenchyme failed in mediating tooth formation. The potentialities of embryonic dental mesenchymal cells decreased from ED14 to ED16 and were lost at ED18. This is likely related to a change in the mesenchymal cell phenotype and/or populations during development. Attempts to cultivate ED14 or ED16 embryonic dental mesenchymal cells prior to re-association led to the loss of their ability to support tooth development. This was accompanied by a down-regulation of Fgf3 transcription. Supplementation of the culture medium with FGF2 allowed restoring Fgf3 expression, but not the ability of mesenchymal cells to engage in tooth formation. Altogether, these observations suggest that a competent cell population exists in the dental mesenchyme at ED14, progressively decreases during development, and cannot as such be maintained in vitro. This study evidenced the need for specific conditions to maintain the ability of dental mesenchymal cells to initiate whole tooth formation, when re-associated with an odontogenic epithelium. Efforts to improve the culture conditions will have to be combined with attempts to characterize the competent cells within the dental mesenchyme.

  17. Mesenchymal Stem Cell Therapy for Nerve Regeneration and Immunomodulation after Composite Tissue Allotransplantation

    Science.gov (United States)

    2012-02-01

    10-1-0927 TITLE: Mesenchymal Stem Cell Therapy for Nerve Regeneration and Immunomodulation after Composite Tissue Allotransplantation...immunosuppression. Bone Marrow Derived Mesenchymal stem cells (BM-MSCs) are pluripotent cells, capable of differentiation along multiple mesenchymal lineages into...As part of implemented transition from University of Pittsburgh to Johns Hopkins University, we optimized our mesenchymal stem cell (MSC) isolation

  18. Contacting gases and liquids

    International Nuclear Information System (INIS)

    Robinson, L.F.; Cahalan, M.J.

    1980-01-01

    A process is described for contacting substantially immiscible phases to transfer material from one phase to another, which comprises passing the phases through a contactor, while causing portions of at least one phase to be repeatedly passed through at least one other phase. One phase in the contactor is gaseous, and another liquid. A further phase can be liquid or solid The process may be used for extracting impurities from china clay, or extracting uranium values from ore with oxygen gas acting to oxidise the uranium. (author)

  19. Precision contact level gauge

    International Nuclear Information System (INIS)

    Krejci, M.; Pilat, M.; Stulik, P.

    1977-01-01

    Equipment was developed measuring the heavy water level in the TR-0 reactor core within an accuracy of several hundredths of a millimeter in a range of around 3.5 m and at a temperature of up to 90 degC. The equipment uses a vibrating needle contact as a high sensitivity level gauge and a servomechanical system with a motion screw carrying the gauge for monitoring and measuring the level in the desired range. The advantage of the unique level gauge consists in that that the transducer converts the measured level position to an electric signal, ie., pulse width, with high sensitivity and without hysteresis. (Kr)

  20. Thermal contact conductance

    CERN Document Server

    Madhusudana, Chakravarti V

    2013-01-01

    The work covers both theoretical and practical aspects of thermal contact conductance. The theoretical discussion focuses on heat transfer through spots, joints, and surfaces, as well as the role of interstitial materials (both planned and inadvertent). The practical discussion includes formulae and data that can be used in designing heat-transfer equipment for a variety of joints, including special geometries and configurations. All of the material has been updated to reflect the latest advances in the field.

  1. Contact ionization ion source

    International Nuclear Information System (INIS)

    Hashmi, N.; Van Der Houven Van Oordt, A.J.

    1975-01-01

    An ion source in which an apertured or foraminous electrode having a multiplicity of openings is spaced from one or more active surfaces of an ionisation electrode, the active surfaces comprising a material capable of ionising by contact ionization a substance to be ionized supplied during operation to the active surface or surfaces comprises means for producing during operation a magnetic field which enables a stable plasma to be formed in the space between the active surface or surfaces and the apertured electrode, the field strength of the magnetic field being preferably in the range between 2 and 8 kilogauss. (U.S.)

  2. Jet Fuel-Associated Occupational Contact Dermatitis.

    Science.gov (United States)

    Contestable, James J

    2017-03-01

    Occupational contact dermatitis is a ubiquitous problem. Sailors onboard U.S. Navy vessels are at high risk given the multitude of potential workplace exposures. Solvents, petrochemicals, and fuels are abundant and can cause irritant or allergic contact dermatitis. Symptoms of contact dermatitis can cause inability to work and, if chronic, may require a change in rating or job. Prevention of this issue requires patient education about the risks and correct personnel protective equipment. Even with preventative strategies in place, exposures and cases of contact dermatitis will occur. Treatment consists of topical steroids and immunomodulators, as well as barrier creams and emollients. The goal of treatment is to fully restore the skin's natural barrier and prevent further exposure. A classic case of jet fuel-associated contact dermatitis is reviewed. A literature review utilizing PubMed, Google Scholar, and Google Search was conducted to elucidate our understanding of this issue, current occupational health guidelines, preventative approaches, and treatments. This case report provides guidance and recommendations for providers who encounter contact dermatitis related to petrochemicals, such as jet fuel. The literature review revealed limited knowledge surrounding in vivo human skin effects of jet fuel, specifically JP-5. Even larger gaps were found in our understanding of, and guidelines for, protective modalities against jet fuel exposure and dermatitis. A case is presented to facilitate recognition of jet fuel contact dermatitis and guidance for treatment and prevention. Given our current limited knowledge and guidelines concerning protective equipment and skin protectants, multiple proposals for future studies are suggested. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  3. Intracardiac heterotopia--mesenchymal and endodermal.

    Science.gov (United States)

    Ariza, S; Rafel, E; Castillo, J A; Garcia-Canton, J A

    1978-01-01

    A case is reported of an intracardiac 'epithelial heterotopia' with a predominant mesenchymal component. This is thought to have resulted from the differentiation of aberrant primitive cell(s) displaced into the heart during its development. Though microscopically resembling a myxoma, this lesion is clearly distinguished by the presence of glandular structures. The myxoid component exhibited a startling invasiveness which resulted in occlusion of the superior vena cava, causing symptoms very early in life and death at the age of 6 months. Images PMID:637987

  4. Snail1 Expression Is Required for Sarcomagenesis

    Directory of Open Access Journals (Sweden)

    Lorena Alba-Castellón

    2014-05-01

    Full Text Available Snail1 transcriptional repressor is a major inducer of epithelial-to mesenchymal transition but is very limitedly expressed in adult animals. We have previously demonstrated that Snail1 is required for the maintenance of mesenchymal stem cells (MSCs, preventing their premature differentiation. Now, we show that Snail1 controls the tumorigenic properties of mesenchymal cells. Increased Snail1 expression provides tumorigenic capabilities to fibroblastic cells; on the contrary, Snail1 depletion decreases tumor growth. Genetic depletion of Snail1 in MSCs that are deficient in p53 tumor suppressor downregulates MSC markers and prevents the capability of these cells to originate sarcomas in immunodeficient SCID mice. Notably, an analysis of human sarcomas shows that, contrarily to epithelial tumors, these neoplasms display high Snail1 expression. This is particularly clear for undifferentiated tumors, which are associated with poor outcome. Together, our results indicate a role for Snail1 in the generation of sarcomas.

  5. Pair housing for female longtailed and rhesus macaques in the laboratory: behavior in protected contact versus full contact.

    Science.gov (United States)

    Baker, Kate C; Crockett, Carolyn M; Lee, Grace H; Oettinger, Brooke C; Schoof, Valérie; Thom, Jinhee P

    2012-01-01

    Pair housing for caged macaques in the laboratory generally allows unrestricted tactile contact but, less commonly, may involve limited contact via grooming-contact bars or perforated panels. The purpose of using this protected contact housing, which prevents entry into pair-mates' cages, typically is to accommodate research and management requirements. The study used behavioral data collected on 12 pairs of female longtailed macaques (Macaca fascicularis) at the Washington National Primate Research Center and 7 pairs of female rhesus macaques (Macaca mulatta) housed at the Tulane National Primate Research Center to assess the relative benefits of protected versus full protected contact. The study collected data in stable pairs housed first in protected contact followed by full contact. Species combined, the study found the presence of the panel was associated with lower levels of social grooming and higher levels of self-grooming, abnormal behavior, and tension-related behavior. Within species, only the protected- versus full-contact contrasts for abnormal and tension were statistically significant-and only for rhesus macaques. Results suggest that for female rhesus macaques, potential disadvantages or inconveniences of full contact should be balanced against the improved behavioral profile in comparison to protected contact. The use of protected contact among female longtailed macaques does not appear to require the same cost-benefit analysis. Copyright © Taylor & Francis Group, LLC

  6. Optimal contact definition for reconstruction of Contact Maps

    Directory of Open Access Journals (Sweden)

    Stehr Henning

    2010-05-01

    Full Text Available Abstract Background Contact maps have been extensively used as a simplified representation of protein structures. They capture most important features of a protein's fold, being preferred by a number of researchers for the description and study of protein structures. Inspired by the model's simplicity many groups have dedicated a considerable amount of effort towards contact prediction as a proxy for protein structure prediction. However a contact map's biological interest is subject to the availability of reliable methods for the 3-dimensional reconstruction of the structure. Results We use an implementation of the well-known distance geometry protocol to build realistic protein 3-dimensional models from contact maps, performing an extensive exploration of many of the parameters involved in the reconstruction process. We try to address the questions: a to what accuracy does a contact map represent its corresponding 3D structure, b what is the best contact map representation with regard to reconstructability and c what is the effect of partial or inaccurate contact information on the 3D structure recovery. Our results suggest that contact maps derived from the application of a distance cutoff of 9 to 11Å around the Cβ atoms constitute the most accurate representation of the 3D structure. The reconstruction process does not provide a single solution to the problem but rather an ensemble of conformations that are within 2Å RMSD of the crystal structure and with lower values for the pairwise average ensemble RMSD. Interestingly it is still possible to recover a structure with partial contact information, although wrong contacts can lead to dramatic loss in reconstruction fidelity. Conclusions Thus contact maps represent a valid approximation to the structures with an accuracy comparable to that of experimental methods. The optimal contact definitions constitute key guidelines for methods based on contact maps such as structure prediction through

  7. Allergic contact dermatitis from octylisothiazolinone

    DEFF Research Database (Denmark)

    Mose, Anja Pahlow; Frost, Simon; Ohlund, Ulf

    2013-01-01

    Octylisothiazolinone is a biocide that has been reported as a moderate, but rare contact allergen.......Octylisothiazolinone is a biocide that has been reported as a moderate, but rare contact allergen....

  8. Reciprocal upregulation of Notch signaling molecules in hematopoietic progenitor and mesenchymal stromal cells

    Directory of Open Access Journals (Sweden)

    Kikuchi Y

    2011-01-01

    Full Text Available Although mesenchymal stem cells (MSCs play pivotal supportive roles in hematopoiesis, how they interact with hematopoietic stem cells (HSCs is not well understood. We investigated the interaction between HSCs and surrogate MSCs (C3H10T1/2 stromal cells, focusing on the molecular events induced by cell contact of these bipartite populations. C3H10T1/2 is a mesenchymal stromal cell line that can be induced to differentiate into preadipocytes (A54 and myoblasts (M1601. The stromal cell derivatives were cocultured with murine HSCs (Lineage-Sca1+, and gene expression profiles in stromal cells and HSCs were compared before and after the coculture. HSCs gave rise to cobblestone areas only on A54 cells, with ninefold more progenitors than on M1601 or undifferentiated C3H10T1/2 cells. Microarray-based screening and a quantitative reverse transcriptase directed-polymerase chain reaction showed that the levels of Notch ligands (Jagged1 and Delta-like 3 were increased in A54 cells upon interaction with HSCs. On the other hand, the expression of Notch1 and Hes1 was upregulated in the HSCs cocultured with A54 cells. A transwell assay revealed that the reciprocal upregulation was dependent on cell-to-cell contact. The result suggested that in the hematopoietic niche, HSCs help MSCs to produce Notch ligands, and in turn, MSCs help HSCs to express Notch receptor. Such a reciprocal upregulation would reinforce the downstream signaling to determine the fate of hematopoietic cell lineage. Clarification of the initiating events on cell contact should lead to the identification of specific molecular targets to facilitate HSC engraftment in transplantation therapy.

  9. Design and fabrication stable LNF contact for future IC application

    International Nuclear Information System (INIS)

    Bhuiyan, M M I; Bhuiyan, M; Rashid, M M; Ahmed, Sayem; Kajihara, M

    2013-01-01

    Enable the design of a small contact spring for applications requiring high density, high speed and high durability. A low normal force (LNF) contact spring with high performance is fabricated using a unique combined MEMS photo resist lithography and electro fine forming (EFF) technology. Reducing a total contact material cost of a connector, a high-Hertz stress with LNF contact will be a key technology in the future. Only radius R 5μm tip with 0.1N force contact provides an excellent electrical performance which is much sharper than conventional contact. 0.30million cycle's durability test was passed at 300μm displacement and the contact resistance was ≤50mΩ

  10. Viability of mesenchymal stem cells during electrospinning

    Directory of Open Access Journals (Sweden)

    G. Zanatta

    2012-02-01

    Full Text Available Tissue engineering is a technique by which a live tissue can be re-constructed and one of its main goals is to associate cells with biomaterials. Electrospinning is a technique that facilitates the production of nanofibers and is commonly used to develop fibrous scaffolds to be used in tissue engineering. In the present study, a different approach for cell incorporation into fibrous scaffolds was tested. Mesenchymal stem cells were extracted from the wall of the umbilical cord and mononuclear cells from umbilical cord blood. Cells were re-suspended in a 10% polyvinyl alcohol solution and subjected to electrospinning for 30 min under a voltage of 21 kV. Cell viability was assessed before and after the procedure by exclusion of dead cells using trypan blue staining. Fiber diameter was observed by scanning electron microscopy and the presence of cells within the scaffolds was analyzed by confocal laser scanning microscopy. After electrospinning, the viability of mesenchymal stem cells was reduced from 88 to 19.6% and the viability of mononuclear cells from 99 to 8.38%. The loss of viability was possibly due to the high viscosity of the polymer solution, which reduced the access to nutrients associated with electric and mechanical stress during electrospinning. These results suggest that the incorporation of cells during fiber formation by electrospinning is a viable process that needs more investigation in order to find ways to protect cells from damage.

  11. Strain and Vibration in Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Brooke McClarren

    2018-01-01

    Full Text Available Mesenchymal stem cells (MSCs are multipotent cells capable of differentiating into any mesenchymal tissue, including bone, cartilage, muscle, and fat. MSC differentiation can be influenced by a variety of stimuli, including environmental and mechanical stimulation, scaffold physical properties, or applied loads. Numerous studies have evaluated the effects of vibration or cyclic tensile strain on MSCs towards developing a mechanically based method of differentiation, but there is no consensus between studies and each investigation uses different culture conditions, which also influence MSC fate. Here we present an overview of the response of MSCs to vibration and cyclic tension, focusing on the effect of various culture conditions and strain or vibration parameters. Our review reveals that scaffold type (e.g., natural versus synthetic; 2D versus 3D can influence cell response to vibration and strain to the same degree as loading parameters. Hence, in the efforts to use mechanical loading as a reliable method to differentiate cells, scaffold selection is as important as method of loading.

  12. Placental Mesenchymal Dysplasia: A Case Report

    Directory of Open Access Journals (Sweden)

    Rachna Agarwal

    2012-01-01

    Full Text Available Introduction. A rare case of histologically proven placental mesenchymal dysplasia (PMD with fetal omphalocele in a 22-year-old patient is reported. Material and Methods. Antenatal ultrasound of this patient showed hydropic placenta with a live fetus of 17 weeks period of gestation associated with omphalocele. Cordocentesis detected the diploid karyotype of the fetus. Patient, when prognosticated, choose to terminate the pregnancy in view of high incidence of fetal and placental anomalies. Subsequent histopathological examination of placenta established the diagnosis to be placental mesenchymal dysplasia. Conclusion. On clinical and ultrasonic grounds, suspicion of P.M.D. arises when hydropic placenta with a live fetus presents in second trimester of pregnancy. Cordocentesis can detect the diploid karyotype of the fetus in such cases. As this condition is prognostically better than triploid partial mole, continuation of pregnancy can sometimes be considered after through antenatal screening and patient counseling. However, a definite diagnosis of P.M.D. is made only on placental histology by absence of trophoblast hyperplasia and trophoblastic inclusions.

  13. Mesenchymal Stromal Cells for Antineoplastic Drug Loading and Delivery.

    Science.gov (United States)

    Petrella, Francesco; Rimoldi, Isabella; Rizzo, Stefania; Spaggiari, Lorenzo

    2017-11-23

    Mesenchymal stromal cells are a population of undifferentiated multipotent adult cells possessing extensive self-renewal properties and the potential to differentiate into a variety of mesenchymal lineage cells. They express broad anti-inflammatory and immunomodulatory activity on the immune system and after transplantation can interact with the surrounding microenvironment, promoting tissue healing and regeneration. For this reason, mesenchymal stromal cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Another clinical application of mesenchymal stromal cells is the targeted delivery of chemotherapeutic agents to neoplastic cells, maximizing the cytotoxic activity against cancer cells and minimizing collateral damage to non-neoplastic tissues. Mesenchymal stem cells are home to the stroma of several primary and metastatic neoplasms and hence can be used as vectors for targeted delivery of antineoplastic drugs to the tumour microenvironment, thereby reducing systemic toxicity and maximizing antitumour effects. Paclitaxel and gemcitabine are the chemotherapeutic drugs best loaded by mesenchymal stromal cells and delivered to neoplastic cells, whereas other agents, like pemetrexed, are not internalized by mesenchymal stromal cells and therefore are not suitable for advanced antineoplastic therapy. This review focuses on the state of the art of advanced antineoplastic cell therapy and its future perspectives, emphasizing in vitro and in vivo preclinical results and future clinical applications.

  14. Stable knockdown of Kif5b in MDCK cells leads to epithelial–mesenchymal transition

    International Nuclear Information System (INIS)

    Cui, Ju; Jin, Guoxiang; Yu, Bin; Wang, Zai; Lin, Raozhou; Huang, Jian-Dong

    2015-01-01

    Polarization of epithelial cells requires vectorial sorting and transport of polarity proteins to apical or basolateral domains. Kif5b is the mouse homologue of the human ubiquitous Kinesin Heavy Chain (uKHC). To investigate the function of Kif5b in epithelial cells, we examined the phenotypes of Kif5b-deficient MDCK cells. Stable knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate, profound changes in cell morphology, loss of epithelial cell marker, and gain of mesenchymal marker, as well as increased cell migration, invasion, and tumorigenesis abilities. E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells, and their expression levels were decreased in Kif5b-deficient MDCK cells. Overexpression of E-cadherin and NMMIIA in Kif5b depleted MDCK cells could decrease mesenchymal marker expression and cell migration ability. These results indicate that stable knockdown of Kif5b in MDCK cells can lead to epithelial–mesenchymal transition, which is mediated by defective E-cadherin and NMMIIA expression. - Highlights: • Knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate. • Kif5b deficient MDCK cells underwent epithelial–mesenchymal transition. • E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells. • Decreased E-cadherin and NMMIIA levels mediate EMT in Kif5b deficient MDCK cells. • Overexpression of E-cadherin and NMMIIA reverse the effects of Kif5b knockdown

  15. Application of human amniotic mesenchymal cells as an allogeneic transplantation cell source in bone regenerative therapy

    International Nuclear Information System (INIS)

    Tsuno, Hiroaki; Yoshida, Toshiko; Nogami, Makiko; Koike, Chika; Okabe, Motonori; Noto, Zenko; Arai, Naoya; Noguchi, Makoto; Nikaido, Toshio

    2012-01-01

    Autogenous mesenchymal stem cells (MSCs) have therapeutic applications in bone regenerative therapy due to their pluripotency. However, the ability of MSCs to proliferate and differentiate varies between donors. Furthermore, alternative sources of MSCs are required for patients with contraindications to autogenous cell therapy. The aim of this study was to evaluate the potential of mesenchymal cells from the human amniotic membrane (HAM) as a source of cells for allogeneic transplantation in bone regenerative therapy. Cells that retained a proliferative capacity of more than 50 population doubling level were distinguished from other HAM cells as HAMα cells and induced to osteogenic status—their in vivo osteogenesis was subsequently investigated in rats. It was found that HAMα cells were spindle shaped and were positive for MSC markers and negative for hematopoietic stem cell markers. Alkaline phosphatase activity and calcium deposition increased with osteogenic status of HAMα cells. The expression of osteocalcin mRNA was increased in HAMα cells cultured on calcium phosphate scaffolds. Moreover, xenografted HAMα cells remained viable and produced extracellular matrix for several weeks. Thus, this study suggests that human amniotic mesenchymal cells possess osteogenic differentiation potential and could be applied to allogeneic transplantation in bone regenerative therapy. - Highlights: ► Human amniotic mesenchymal cells include cells (HAMα cells) that have the properties of MSCs. ► HAMα cells have excellent osteogenic differentiation potential. ► Osteogenic differentiation ability of HAMα was amplified by calcium phosphate scaffolds. ► HAMα cells can be applicable to allogeneic cell transplantation in bone regenerative therapy.

  16. Application of human amniotic mesenchymal cells as an allogeneic transplantation cell source in bone regenerative therapy

    Energy Technology Data Exchange (ETDEWEB)

    Tsuno, Hiroaki [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Yoshida, Toshiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nogami, Makiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Orthopedic Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Koike, Chika; Okabe, Motonori [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Noto, Zenko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Arai, Naoya; Noguchi, Makoto [Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nikaido, Toshio, E-mail: tnikaido@med.u-toyama.ac.jp [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan)

    2012-12-01

    Autogenous mesenchymal stem cells (MSCs) have therapeutic applications in bone regenerative therapy due to their pluripotency. However, the ability of MSCs to proliferate and differentiate varies between donors. Furthermore, alternative sources of MSCs are required for patients with contraindications to autogenous cell therapy. The aim of this study was to evaluate the potential of mesenchymal cells from the human amniotic membrane (HAM) as a source of cells for allogeneic transplantation in bone regenerative therapy. Cells that retained a proliferative capacity of more than 50 population doubling level were distinguished from other HAM cells as HAM{alpha} cells and induced to osteogenic status-their in vivo osteogenesis was subsequently investigated in rats. It was found that HAM{alpha} cells were spindle shaped and were positive for MSC markers and negative for hematopoietic stem cell markers. Alkaline phosphatase activity and calcium deposition increased with osteogenic status of HAM{alpha} cells. The expression of osteocalcin mRNA was increased in HAM{alpha} cells cultured on calcium phosphate scaffolds. Moreover, xenografted HAM{alpha} cells remained viable and produced extracellular matrix for several weeks. Thus, this study suggests that human amniotic mesenchymal cells possess osteogenic differentiation potential and could be applied to allogeneic transplantation in bone regenerative therapy. - Highlights: Black-Right-Pointing-Pointer Human amniotic mesenchymal cells include cells (HAM{alpha} cells) that have the properties of MSCs. Black-Right-Pointing-Pointer HAM{alpha} cells have excellent osteogenic differentiation potential. Black-Right-Pointing-Pointer Osteogenic differentiation ability of HAM{alpha} was amplified by calcium phosphate scaffolds. Black-Right-Pointing-Pointer HAM{alpha} cells can be applicable to allogeneic cell transplantation in bone regenerative therapy.

  17. Role of microRNA in epithelial to mesenchymal transition and metastasis and clinical perspectives

    International Nuclear Information System (INIS)

    Díaz-López, Antonio; Moreno-Bueno, Gema; Cano, Amparo

    2014-01-01

    The microRNAs (miRNAs) are a class of small, 20–22 nucleotides in length, endogenously expressed noncoding RNAs that regulate multiple targets posttranscriptionally. Interestingly, miRNAs have emerged as regulators of most physiological and pathological processes, including metastatic tumor progression, in part by controlling a reversible process called epithelial-to-mesenchymal transition (EMT). The activation of EMT increases the migratory and invasive properties fundamental for tumor cell spread while activation of the reverse mesenchymal-to-epithelial transition is required for metastasis outgrowth. The EMT triggering leads to the activation of a core of transcription factors (EMT-TFs) – SNAIL1/SNAIL2, bHLH (E47, E2-2, and TWIST1/TWIST2), and ZEB1/ZEB2 – that act as E-cadherin repressors and, ultimately, coordinate EMT. Recent evidence indicates that several miRNAs regulate the expression of EMT-TFs or EMT-activating signaling pathways. Interestingly, some miRNAs and EMT-TFs form tightly interconnected negative feedback loops that control epithelial cell plasticity, providing self-reinforcing signals and robustness to maintain the epithelial or mesenchymal cell status. Among the most significant feedback loops, we focus on the ZEB/miR-200 and the SNAIL1/miR-34 networks that hold a clear impact in the regulation of the epithelial-mesenchymal state. Recent insights into the p53 modulation of the EMT-TF/miRNA loops and epigenetic regulatory mechanisms in the context of metastasis dissemination will also be discussed. Understanding the regulation of EMT by miRNAs opens new avenues for the diagnosis and prognosis of tumors and identifies potential therapeutic targets that might help to negatively impact on metastasis dissemination and increasing patient survival

  18. Stable knockdown of Kif5b in MDCK cells leads to epithelial–mesenchymal transition

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Ju, E-mail: juzi.cui@gmail.com [The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing (China); Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Jin, Guoxiang; Yu, Bin [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Wang, Zai [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing (China); Lin, Raozhou [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); Huang, Jian-Dong, E-mail: jdhuang@hku.hk [Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR (China); The Centre for Synthetic Biology Engineering Research, Shenzhen Institutes of Advanced Technology, Shenzhen (China)

    2015-07-17

    Polarization of epithelial cells requires vectorial sorting and transport of polarity proteins to apical or basolateral domains. Kif5b is the mouse homologue of the human ubiquitous Kinesin Heavy Chain (uKHC). To investigate the function of Kif5b in epithelial cells, we examined the phenotypes of Kif5b-deficient MDCK cells. Stable knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate, profound changes in cell morphology, loss of epithelial cell marker, and gain of mesenchymal marker, as well as increased cell migration, invasion, and tumorigenesis abilities. E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells, and their expression levels were decreased in Kif5b-deficient MDCK cells. Overexpression of E-cadherin and NMMIIA in Kif5b depleted MDCK cells could decrease mesenchymal marker expression and cell migration ability. These results indicate that stable knockdown of Kif5b in MDCK cells can lead to epithelial–mesenchymal transition, which is mediated by defective E-cadherin and NMMIIA expression. - Highlights: • Knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate. • Kif5b deficient MDCK cells underwent epithelial–mesenchymal transition. • E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells. • Decreased E-cadherin and NMMIIA levels mediate EMT in Kif5b deficient MDCK cells. • Overexpression of E-cadherin and NMMIIA reverse the effects of Kif5b knockdown.

  19. Fragrance contact allergy

    DEFF Research Database (Denmark)

    Johansen, Jeanne D

    2003-01-01

    in the same products. This means that it is difficult to avoid exposure, as products labelled as 'fragrance free' have also been shown to contain fragrance ingredients, either because of the use of fragrance ingredients as preservatives or masking perfumes, or the use of botanicals. About 2500 different...... fragrance ingredients are currently used in the composition of perfumes and at least 100 of these are known contact allergens. Therefore, it is advisable to supplement standard patch testing with the patient's own stay-on cosmetic products, as well as the fragrance chemical hydroxyisohexyl-3-cyclohexane...... carboxaldehyde, which on its own gives responses in 1-3% of tested patients. The focus in recent years on the ingredients of the fragrance mix will probably result in the fragrance industry changing the composition of perfumes, and thus make the current diagnostic test less useful. New diagnostic tests are under...

  20. Cosmetic Contact Allergens

    Directory of Open Access Journals (Sweden)

    An Goossens

    2016-02-01

    Full Text Available This article presents trends in the frequency of cosmetics as causal factors of allergic contact dermatitis during a 26-year period in 14,911 patients patch-tested between 1990 and 2014, and discusses the cosmetic allergens identified during the last six years (2010–2015 in 603 patients out of 3105 tested. The data were retrieved from, and evaluated with, a patient database developed in-house. The results show the increasing importance of cosmetic allergies, up to 25% of the patients tested during the last five-year period. As expected, fragrance materials, preservatives, and hair dyes were the most frequent culprits, but a great variety of other allergenic ingredients were involved as well. This underlines the need of additional and extensive patch testing with the patient’s products used and their ingredients.

  1. Hair dye contact allergy

    DEFF Research Database (Denmark)

    Søsted, Heidi; Rastogi, Suresh Chandra; Andersen, Klaus Ejner

    2004-01-01

    Colouring of hair can cause severe allergic contact dermatitis. The most frequently reported hair dye allergens are p-phenylenediamine (PPD) and toluene-2,5-diamine, which are included in, respectively, the patch test standard series and the hairdressers series. The aim of the present study...... was to identify dye precursors and couplers in hair dyeing products causing clinical hair dye dermatitis and to compare the data with the contents of these compounds in a randomly selected set of similar products. The patient material comprised 9 cases of characteristic clinical allergic hair dye reaction, where...... exposure history and patch testing had identified a specific hair dye product as the cause of the reaction. The 9 products used by the patients were subjected to chemical analysis. 8 hair dye products contained toluene-2,5-diamine (0.18 to 0.98%). PPD (0.27%) was found in 1 product, and m-aminophenol (0...

  2. PHD-2 Suppression in Mesenchymal Stromal Cells Enhances Wound Healing.

    Science.gov (United States)

    Ko, Sae Hee; Nauta, Allison C; Morrison, Shane D; Hu, Michael S; Zimmermann, Andrew S; Chung, Michael T; Glotzbach, Jason P; Wong, Victor W; Walmsley, Graham G; Peter Lorenz, H; Chan, Denise A; Gurtner, Geoffrey C; Giaccia, Amato J; Longaker, Michael T

    2018-01-01

    Cell therapy with mesenchymal stromal cells is a promising strategy for tissue repair. Restoration of blood flow to ischemic tissues is a key step in wound repair, and mesenchymal stromal cells have been shown to be proangiogenic. Angiogenesis is critically regulated by the hypoxia-inducible factor (HIF) superfamily, consisting of transcription factors targeted for degradation by prolyl hydroxylase domain (PHD)-2. The aim of this study was to enhance the proangiogenic capability of mesenchymal stromal cells and to use these modified cells to promote wound healing. Mesenchymal stromal cells harvested from mouse bone marrow were transduced with short hairpin RNA (shRNA) against PHD-2; control cells were transduced with scrambled shRNA (shScramble) construct. Gene expression quantification, human umbilical vein endothelial cell tube formation assays, and wound healing assays were used to assess the effect of PHD knockdown mesenchymal stromal cells on wound healing dynamics. PHD-2 knockdown mesenchymal stromal cells overexpressed HIF-1α and multiple angiogenic factors compared to control (p cells treated with conditioned medium from PHD-2 knockdown mesenchymal stromal cells exhibited increased formation of capillary-like structures and enhanced migration compared with human umbilical vein endothelial cells treated with conditioned medium from shScramble-transduced mesenchymal stromal cells (p cells healed at a significantly accelerated rate compared with wounds treated with shScramble mesenchymal stromal cells (p cells (p cells augments their proangiogenic potential in wound healing therapy. This effect appears to be mediated by overexpression of HIF family transcription factors and up-regulation of multiple downstream angiogenic factors.

  3. Mechanoluminescent Contact Type Sensor

    Directory of Open Access Journals (Sweden)

    A. K. Yefremov

    2017-01-01

    Full Text Available Mechanoluminescent sensing elements convert mechanical stress into optical radiation. Advantages of such sensors are the ability to generate an optical signal, solid-state, simple structure, and resistance to electromagnetic interference. Mechanoluminescent sensor implementations can possess the concentrated and distributed sensitivity, thereby allowing us to detect the field of mechanical stresses distributed across the area and in volume. Most modern semiconductor photo-detectors can detect mechanoluminescent radiation, so there are no difficulties to provide its detection when designing the mechanoluminescent sensing devices. Mechanoluminescent substances have especial sensitivity to shock loads, and this effect can be used to create a fuse the structure of which includes a target contact type sensor with a photosensitive actuator. The paper briefly describes the theoretical basics of mechanoluminiscence: a light signal emerges from the interaction of crystalline phosphor luminescence centers with electrically charged dislocations, moving due to the deformation of the crystal. A mathematical model of the mechanoluminescent conversion is represented as a functional interaction between parameters of the mechanical shock excitation and the sensor light emission. Examples of computing the optical mechanoluminescent output signal depending on the duration and peak level of impulse load are given. It is shown that the luminous flux, generated by mechanoluminescent sensing element when there is an ammunition-target collision causes the current emerging in photo-detector (photodiode that is sufficient for a typical actuator of the fuse train to operate. The potential possibility to create a contact target type sensor based on the light-sensitive mechanoluminescent sensor was proved by the calculation and simulation results.

  4. Positively charged polymers modulate the fate of human mesenchymal stromal cells via ephrinB2/EphB4 signaling

    Directory of Open Access Journals (Sweden)

    Ilenia De Luca

    2016-09-01

    Full Text Available Understanding the mechanisms by which mesenchymal stromal cells (MSCs interact with the physical properties (e.g. topography, charge, ζ-potential, and contact angle of polymeric surfaces is essential to design new biomaterials capable of regulating stem cell behavior. The present study investigated the ability of two polymers (pHM1 and pHM3 with different positive surface charge densities to modulate the differentiation of MSCs into osteoblast-like phenotype via cell-cell ephrinB2/EphB4 signaling. Although pHM1 promoted the phosphorylation of EphB4, leading to cell differentiation, pHM3, characterized by a high positive surface charge density, had no significant effect on EphB4 activation or MSCs differentiation. When the MSCs were cultured on pHM1 in the presence of a forward signaling blocking peptide, the osteoblast differentiation was compromised. Our results demonstrated that the ephrinB2/EphB4 interaction was required for MSCs differentiation into an osteoblast-like phenotype and that the presence of a high positive surface charge density altered this interaction.

  5. Radiofrequency contact currents: sensory responses and dosimetry

    International Nuclear Information System (INIS)

    Kavet, Robert; Tell, R.A.; Olsen, R.G.

    2014-01-01

    The process of setting science-based exposure standards (or guidelines) for radiofrequency (RF) contact current exposure has been disadvantaged by a lack of relevant data. The authors first review the essential features and results of the available studies and illustrate the apparent discrepancies among them. Then, they examine the manner in which current was administered in these studies and suggest as to how the physical relationship of a contacting finger to the current electrode may play a role in affecting sensory thresholds specific to those configurations. A major factor in this analysis relates to whether current density is uniformly distributed across the contact area or whether an electrode's 'edge effects' enhance currents with a net effect of decreasing apparent thresholds, when expressed as the bulk current entering a subject. For an exposure with a clear hazard potential, thresholds of human sensory response to RF currents require further investigation. (authors)

  6. A Germanium Back Contact Type Thermophotovoltaic Cell

    International Nuclear Information System (INIS)

    Nagashima, Tomonori; Okumura, Kenichi; Yamaguchi, Masafumi

    2007-01-01

    A Ge back contact type photovoltaic cell has been proposed to reduce resistance loss for high current densities in thermophotovoltaic systems. The back contact structure requires less surface recombination velocities than conventional structures with front grid contacts. A SiO2/SiNx double anti-reflection coating including a high refractive index SiNx layer was studied. The SiNx layer has an enough passivation effect to obtain high efficiency. The quantum efficiency of the Ge cell was around 0.8 in the 800-1600 nm wavelength range. The conversion efficiency for infrared lights was estimated at 18% for a blackbody surface and 25% for a selective emitter by using the quantum efficiency and a simulation analysis

  7. Contact angle and local wetting at contact line.

    Science.gov (United States)

    Li, Ri; Shan, Yanguang

    2012-11-06

    This theoretical study was motivated by recent experiments and theoretical work that had suggested the dependence of the static contact angle on the local wetting at the triple-phase contact line. We revisit this topic because the static contact angle as a local wetting parameter is still not widely understood and clearly known. To further clarify the relationship of the static contact angle with wetting, two approaches are applied to derive a general equation for the static contact angle of a droplet on a composite surface composed of heterogeneous components. A global approach based on the free surface energy of a thermodynamic system containing the droplet and solid surface shows the static contact angle as a function of local surface chemistry and local wetting state at the contact line. A local approach, in which only local forces acting on the contact line are considered, results in the same equation. The fact that the local approach agrees with the global approach further demonstrates the static contact angle as a local wetting parameter. Additionally, the study also suggests that the wetting described by the Wenzel and Cassie equations is also the local wetting of the contact line rather than the global wetting of the droplet.

  8. Equilibrium contact angle or the most-stable contact angle?

    Science.gov (United States)

    Montes Ruiz-Cabello, F J; Rodríguez-Valverde, M A; Cabrerizo-Vílchez, M A

    2014-04-01

    It is well-established that the equilibrium contact angle in a thermodynamic framework is an "unattainable" contact angle. Instead, the most-stable contact angle obtained from mechanical stimuli of the system is indeed experimentally accessible. Monitoring the susceptibility of a sessile drop to a mechanical stimulus enables to identify the most stable drop configuration within the practical range of contact angle hysteresis. Two different stimuli may be used with sessile drops: mechanical vibration and tilting. The most stable drop against vibration should reveal the changeless contact angle but against the gravity force, it should reveal the highest resistance to slide down. After the corresponding mechanical stimulus, once the excited drop configuration is examined, the focus will be on the contact angle of the initial drop configuration. This methodology needs to map significantly the static drop configurations with different stable contact angles. The most-stable contact angle, together with the advancing and receding contact angles, completes the description of physically realizable configurations of a solid-liquid system. Since the most-stable contact angle is energetically significant, it may be used in the Wenzel, Cassie or Cassie-Baxter equations accordingly or for the surface energy evaluation. © 2013 Elsevier B.V. All rights reserved.

  9. Contact and Non-contact Measurements of Grinding Pins

    Directory of Open Access Journals (Sweden)

    Magdziak Marek

    2015-01-01

    Full Text Available The paper presents the results of contact and non-contact measurements of external profiles of selected grinding pins. The measurements were conducted in order to choose the appropriate measuring technique in the case of the considered measurement task. In the case of contact measurements the coordinate measuring machine ACCURA II was applied. The used coordinate measuring machine was equipped with the contact scanning probe VAST XT and the Calypso inspection software. Contact coordinate measurements were performed by using of different measurement strategies. The applied strategies included different scanning velocities and distances between measured points. Non-contact measurements were conducted by means of the tool presetter produced by the Mahr company. On the basis of gained results the guidelines concerning measurements of grinding pins were formulated. The measurements of analyzed grinding pins performed by means of the non-contact measuring system are characterized by higher reproducibility than the contact measurements. The low reproducibility of contact measurements may be connected with the inaccuracy of the selected coordinate measuring machine and the measuring probe, the measurement parameters and environmental conditions in the laboratory where the coordinate measuring machine is located. Moreover, the paper presents the possible application of results of conducted investigations. The results of non-contact measurements can be used in the simulation studies of grinding processes. The simulations may reduce the costs of machining processes.

  10. Bi-directional exchange of membrane components occurs during co-culture of mesenchymal stem cells and nucleus pulposus cells.

    Science.gov (United States)

    Strassburg, Sandra; Hodson, Nigel W; Hill, Patrick I; Richardson, Stephen M; Hoyland, Judith A

    2012-01-01

    Mesenchymal stem cell (MSC)-based therapies have been proposed as novel treatments for intervertebral disc (IVD) degeneration. We have previously demonstrated that when MSCs are co-cultured with nucleus pulposus (NP) cells with direct cell-cell contact, they differentiate along the NP lineage and simultaneously stimulate the degenerate NP cell population to regain a normal (non-degenerate) phenotype, an effect which requires cell-cell communication. However, the mechanisms by which NP cells and MSCs interact in this system are currently unclear. Thus, in this study we investigated a range of potential mechanisms for exchange of cellular components or information that may direct these changes, including cell fusion, gap-junctional communication and exchange of membrane components by direct transfer or via microvesicle formation. Flow cytometry of fluorescently labeled MSCs and NP cells revealed evidence of some cell fusion and formation of gapjunctions, although at the three timepoints studied these phenomena were detectable only in a small proportion of cells. While these mechanisms may play a role in cell-cell communication, the data suggests they are not the predominant mechanism of interaction. However, flow cytometry of fluorescently dual-labeled cells showed that extensive bi-directional transfer of membrane components is operational during direct co-culture of MSCs and NP cells. Furthermore, there was also evidence for secretion and internalization of membrane-bound microvesicles by both cell types. Thus, this study highlights bi-directional intercellular transfer of membrane components as a possible mechanism of cellular communication between MSC and NP cells.

  11. Mathematical Modeling of Contact Problems of Elasticity Theory with Unilateral Discrete Contact

    Directory of Open Access Journals (Sweden)

    I. V. Stankevich

    2015-01-01

    Full Text Available Development and operation of modern machinery and latest technology require reliable estimates of the strength characteristics of the critical elements of structures and technological equipment under the impact of high-intensity thermomechanical loading, accompanied, as a rule, by complex contact interaction. Mathematical modeling of stress-strain state of such parts and components in the contact area, based on adequate mathematical models, modern numerical methods and efficient algorithms that implement the direct determination of displacement fields, strains and stresses, is the main tool that allows fast acquisition of data required for the calculations of strength and durability. The paper considers an algorithm for constructing the numerical solution of the contact problem of elasticity theory in relation to the body, which has an obvious one-sided discrete contact interaction with an elastic half-space. The proposed algorithm is specially designed to have a correction of the tangential forces at discrete contact points, allowing us to achieve sufficiently accurate implementation of the adopted law of friction. The algorithm is embedded in a general finite element technology, with which the application code is generated. Numerical study of discrete unilateral contact interaction of an elastic plate and a rigid half-space showed a high efficiency of the developed algorithm and the application code that implements it.

  12. Bi-directional Activation between Mesenchymal Stem Cells and CLL B-Cells: Implication for CLL Disease Progression

    OpenAIRE

    Ding, Wei; Nowakowski, Grzegorz S.; Knox, Traci R.; Boysen, Justin C.; Maas, Mary L.; Schwager, Susan M.; Wu, Wenting; Wellik, Linda E.; Dietz, Allan B.; Ghosh, Asish K.; Secreto, Charla R.; Medina, Kay L.; Shanafelt, Tait D.; Zent, Clive S.; Call, Timothy G.

    2009-01-01

    It was hypothesized that contact between chronic lymphocytic leukemia (CLL) B-cells and marrow stromal cells impact both cell types. To test this hypothesis, we utilized a long-term primary culture system from bone biopsies that reliably generates a mesenchymal stem cell (MSC). Co-culture of MSC with CLL B-cells protected the latter from both spontaneous apoptosis and drug-induced apoptosis. The CD38 expression in previously CD38 positive CLL B-cells was up-regulated with MSC co-culture. Up-r...

  13. Extraskeletal mesenchymal chondrosarcoma of the carotid space: A case report

    International Nuclear Information System (INIS)

    Huh, Sun; Hong, Hyun Sook; Kwak, Jeong Ja; Park, Ji Sang; Jeong, Sun Hye

    2015-01-01

    Chondrosarcoma is a commonly encountered malignant cartilaginous tumor. However, only 1% of chondrosarcomas arise in the extraskeletal region. The pathologic types of this tumor include mesenchymal, myxoid, and low grade. A mesenchymal chondrosarcoma is a rare, highly malignant cartilaginous tumor that is rarely encountered, and it shows similar imaging features to other malignant soft-tissue tumors. Here, we report a mesenchymal chondrosarcoma presenting as a palpable mass in the neck, arising in the carotid space, which is also known as the retrostyloid parapharyngeal space.

  14. Extraskeletal mesenchymal chondrosarcoma of the carotid space: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Sun; Hong, Hyun Sook; Kwak, Jeong Ja; Park, Ji Sang; Jeong, Sun Hye [Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of)

    2015-05-15

    Chondrosarcoma is a commonly encountered malignant cartilaginous tumor. However, only 1% of chondrosarcomas arise in the extraskeletal region. The pathologic types of this tumor include mesenchymal, myxoid, and low grade. A mesenchymal chondrosarcoma is a rare, highly malignant cartilaginous tumor that is rarely encountered, and it shows similar imaging features to other malignant soft-tissue tumors. Here, we report a mesenchymal chondrosarcoma presenting as a palpable mass in the neck, arising in the carotid space, which is also known as the retrostyloid parapharyngeal space.

  15. Mesenchymal Tumors of the Breast: Imaging and the Histopathologic Correlation

    International Nuclear Information System (INIS)

    Kim, Bo Mi; Kim, Eun Kyung; You, Jae Kyoung; Kim, Yee Jeong

    2011-01-01

    Various benign and malignant mesenchymal tumors can occur in the breast. Most radiologists are unfamiliar with the imaging features of these tumors and the imaging features have not been described in the radiologic literature. It is important that radiologists should be familiar with the broad spectrum of imaging features of rare mesenchymal breast tumors. In this pictorial review, we demonstrate the sonographic findings and the corresponding pathologic findings of various mesenchymal tumors of the breast as defined by the World Health Organization classification system

  16. Soft-contact-lenses-induced complications

    Directory of Open Access Journals (Sweden)

    Suvajac Gordana

    2008-01-01

    Full Text Available Background/Aim. Soft contact lenses occupy significant place in ophthalmology, both in the correction of refraction anomalies and in the treatment of many eye diseases. The number of patients that wear soft contact lenses for the purpose of correcting ametropia is constantly increasing. Due to the increasing number of wearers, the percentage of complications that can lead to serious eye damage and serious vision loss is also increasing. The aim of this study was to point out the most common complications related to soft contact lens use. Methods. In the period from 1995−2004 this prospective study included 510 patients wearing soft contact lenses for correcting ametropia. None of the patients wore contact lenses before and none suffered from any system or local diseases that could affected the development of eventual complications. The study took seven years with the patients who wore conventional lenses and three years with those who wore replacement contact lenses. All the necessary ophthalmologic examinations were done (visual acuity, refractokeratometry, the quantity of tear film, biomicroscopic examination of anterior eye segment. All the complications were filmed by video camera. Results. Of all the patients, 19 had blepharitis, 73 suffered from “dry eye”, 57 had conjunctival hyperemia, 12 had conjunctivitis, 34 had gigantopapillary conjunctivitis (GPC, 93 had punctiform epitheliopathy, 20 had corneal infiltration, one patient had keratitis, 91 had corneal vascularisation, and 95 patients had corneal deposits. Conclusion. Both the type and frequency of complications related to soft contact lens use in our group of patients, proved to be significant. Some of this complications (keratitis can significantly damage vision and lead to loss of vision and sometimes can require operative treatment.

  17. Gas fireplace contact burns in young children.

    Science.gov (United States)

    Zettel, Julie C; Khambalia, Amina; Barden, Wendy; Murthy, Trisha; Macarthur, Colin

    2004-01-01

    Contact burns from domestic appliances are common in young children. Recently, gas fireplaces have been recognized as a potential cause of contact burns in young children. We sought to quantify the frequency of gas fireplace contact burns in young children, to identify the etiology of contact, to describe the clinical presentation, and to describe clinical outcomes. Children with gas fireplace contact burn injuries presenting to The Hospital for Sick Children in Toronto (1999-2002) were identified using three data sources: the Canadian Hospitals Injury Reporting and Prevention Program Database, the Burn Unit Registry, and the Rehabilitation Services Database. Demographic, clinical, and outcomes data were collected on all children. During the 4-year study period, 27 children presented to the hospital because of a gas fireplace contact burn (approximately 9% of all contact burns). The median age of the children was 14 months (range, 8-36 months), with 16 boys (59%). Most children were burned in their own home. With regard to etiology, 10 children (37%) lost their balance near the fireplace, 2 (7%) walked too close to the glass front, and 8 (30%) touched the glass front out of curiosity. Almost half (44%) of the children burned the palms and digits of both hands. The median total burn surface area was 1% (range, 0.2-2.5%). In total, 30% of children were admitted to hospital, and 11% required skin grafts. All children had full wound closure after 4 to 43 days. Given the etiology of these burns (loss of balance or curiosity), passive prevention, such as barriers or changes in the composition of glass panels, may be the most effective approach to combat them.

  18. Adaptive Regulation of Osteopontin Production by Dendritic Cells Through the Bidirectional Interaction With Mesenchymal Stromal Cells

    Directory of Open Access Journals (Sweden)

    Sara Scutera

    2018-06-01

    Full Text Available Mesenchymal stromal cells (MSCs exert immunosuppressive effects on immune cells including dendritic cells (DCs. However, many details of the bidirectional interaction of MSCs with DCs are still unsolved and information on key molecules by which DCs can modulate MSC functions is limited. Here, we report that osteopontin (OPN, a cytokine involved in homeostatic and pathophysiologic responses, is constitutively expressed by DCs and regulated in the DC/MSC cocultures depending on the activation state of MSCs. Resting MSCs promoted OPN production, whereas the production of OPN was suppressed when MSCs were activated by proinflammatory cytokines (i.e., TNF-α, IL-6, and IL-1β. OPN induction required cell-to-cell contact, mediated at least in part, by β1 integrin (CD29. Conversely, activated MSCs inhibited the release of OPN via the production of soluble factors with a major role played by Prostaglandin E2 (PGE2. Accordingly, pretreatment with indomethacin significantly abrogated the MSC-mediated suppression of OPN while the direct addition of exogenous PGE2 inhibited OPN production by DCs. Furthermore, DC-conditioned medium promoted osteogenic differentiation of MSCs with a concomitant inhibition of adipogenesis. These effects were paralleled by the repression of the adipogenic markers PPARγ, adiponectin, and FABP4, and induction of the osteogenic markers alkaline phosphatase, RUNX2, and of the bone-anabolic chemokine CCL5. Notably, blocking OPN activity with RGD peptides or with an antibody against CD29, one of the OPN receptors, prevented the effects of DC-conditioned medium on MSC differentiation and CCL5 induction. Because MSCs have a key role in maintenance of bone marrow (BM hematopoietic stem cell niche through reciprocal regulation with immune cells, we investigated the possible MSC/DC interaction in human BM by immunohistochemistry. Although DCs (CD1c+ are a small percentage of BM cells, we demonstrated colocalization of CD271+ MSCs with

  19. Illustration of extensive extracellular matrix at the epithelial-mesenchymal interface within the renal stem/progenitor cell niche

    Directory of Open Access Journals (Sweden)

    Minuth Will W

    2012-09-01

    Full Text Available Abstract Background Stem/progenitor cells are promising candidates to treat diseased renal parenchyma. However, implanted stem/progenitor cells are exposed to a harmful atmosphere of degenerating parenchyma. To minimize hampering effects after an implantation investigations are in progress to administer these cells within an artificial polyester interstitum supporting survival. Learning from nature the renal stem/progenitor cell niche appears as a valuable model. At this site epithelial stem/progenitor cells within the collecting duct ampulla face mesenchymal stem/progenitor cells. Both cell types do not have close contact but are separated by a wide interstitium. Methods To analyze extracellular matrix in this particular interstitium, special contrasting for transmission electron microscopy was performed. Kidneys of neonatal rabbits were fixed in solutions containing glutaraldehyde (GA or in combination with cupromeronic blue, ruthenium red and tannic acid. Results GA revealed a basal lamina at the ampulla and a bright but inconspicuously looking interstitial space. In contrast, GA containing cupromeronic blue exhibits numerous proteoglycan braces lining from the ampulla towards the interstitial space. GA containing ruthenium red or tannic acid demonstrates clouds of extracellular matrix protruding from the basal lamina of the ampulla to the surface of mesenchymal stem/progenitor cells. Conclusions The actual data show that the interstitium between epithelial and mesenchymal stem/progenitor cells contains much more and up to date unknown extracellular matrix than earlier observed by classical GA fixation.

  20. CD54-Mediated Interaction with Pro-inflammatory Macrophages Increases the Immunosuppressive Function of Human Mesenchymal Stromal Cells

    Directory of Open Access Journals (Sweden)

    Nicolas Espagnolle

    2017-04-01

    Full Text Available Summary: Mesenchymal stromal cells (MSCs sense and modulate inflammation and represent potential clinical treatment for immune disorders. However, many details of the bidirectional interaction of MSCs and the innate immune compartment are still unsolved. Here we describe an unconventional but functional interaction between pro-inflammatory classically activated macrophages (M1MΦ and MSCs, with CD54 playing a central role. CD54 was upregulated and enriched specifically at the contact area between M1MФ and MSCs. Moreover, the specific interaction induced calcium signaling and increased the immunosuppressive capacities of MSCs dependent on CD54 mediation. Our data demonstrate that MSCs can detect an inflammatory microenvironment via a direct and physical interaction with innate immune cells. This finding opens different perspectives for MSC-based cell therapy. : Mesenchymal stromal cells (MSCs are promising for cell-based therapy in inflammatory disorders by switching off the immune response. Varin and colleagues demonstrate that MSCs and inflammatory macrophages communicate via an unconventional but functional interaction that strongly increases the immunosuppressive capacities of MSCs. This new communication between the innate immune system and MSCs opens new perspectives for MSC-based cell therapy. Keywords: macrophages, bone marrow mesenchymal stromal cells, functional interaction, CD54, immunosuppression, indoleamine 2,3-dioxygenase, cell therapy

  1. Contact engineering for nano-scale CMOS

    KAUST Repository

    Hussain, Muhammad Mustafa

    2012-09-10

    High performance computation with longer battery lifetime is an essential component in our today\\'s digital electronics oriented life. To achieve these goals, field effect transistors based complementary metal oxide semiconductor play the key role. One of the critical requirements of transistor structure and fabrication is efficient contact engineering. To catch up with high performance information processing, transistors are going through continuous scaling process. However, it also imposes new challenges to integrate good contact materials in a small area. This can be counterproductive as smaller area results in higher contact resistance thus reduced performance for the transistor itself. At the same time, discovery of new one or two-dimensional materials like nanowire, nanotube, or atomic crystal structure materials, introduces new set of challenges and opportunities. In this paper, we are reviewing them in a synchronized fashion: fundamentals of contact engineering, evolution into non-planar field effect transistors, opportunities and challenges with one and two-dimensional materials and a new opportunity of contact engineering from device architecture perspective. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Contact Binaries on Their Way Towards Merging

    Science.gov (United States)

    Gazeas, K.

    2015-07-01

    Contact binaries are the most frequently observed type of eclipsing star system. They are small, cool, low-mass binaries belonging to a relatively old stellar population. They follow certain empirical relationships that closely connect a number of physical parameters with each other, largely because of constraints coming from the Roche geometry. As a result, contact binaries provide an excellent test of stellar evolution, specifically for stellar merger scenarios. Observing campaigns by many authors have led to the cataloging of thousands of contact binaries and enabled statistical studies of many of their properties. A large number of contact binaries have been found to exhibit extraordinary behavior, requiring follow-up observations to study their peculiarities in detail. For example, a doubly-eclipsing quadruple system consisting of a contact binary and a detached binary is a highly constrained system offering an excellent laboratory to test evolutionary theories for binaries. A new observing project was initiated at the University of Athens in 2012 in order to investigate the possible lower limit for the orbital period of binary systems before coalescence, prior to merging.

  3. Experimental photoallergic contact dermatitis: a mouse model

    International Nuclear Information System (INIS)

    Maguire, H.C. Jr.; Kaidbey, K.

    1982-01-01

    We have induced photoallergic contact dermatitis in mice to 3,3',4',5 tetrachlorosalicylanilide (TCSA), chlorpromazine and 6-methylcoumarin. These compounds are known to produce photoallergic contact dermatitis in humans. The photoallergic contact dermatitis reaction in the mouse is immunologically specific viz. mice photosensitized to TCSA react, by photochallenge, to that compound and not to chlorpromazine, and conversely. The reaction requires UVA at both sensitization and challenge. It appears to be T-cell mediated in that it can be passively transferred to syngeneic mice by lymph node cells from actively sensitized mice, the histology of the reactions resembles that of classic allergic contact dermatitis in mice, challenge reactions are seen at 24 but not at 4 hr, and photoallergic contact dermatitis can be induced in B-cell deficient mice. The availability of a mouse model for the study of photo-ACD will facilitate the identification of pertinent control mechanisms and may aid in the management of the disease. It is likely that a bioassay for photoallergens of humans can be based on this mouse model

  4. Decreased Intracellular pH Induced by Cariporide Differentially Contributes to Human Umbilical Cord-Derived Mesenchymal Stem Cells Differentiation

    Directory of Open Access Journals (Sweden)

    Wei Gao

    2014-01-01

    Full Text Available Background/Aims: Na+/H+ exchanger 1 (NHE1 is an important regulator of intracellular pH (pHi. High pHi is required for cell proliferation and differentiation. Our previous study has proven that the pHi of mesenchymal stem cells is higher than that of normal differentiated cells and similar to tumor cells. NHE1 is highly expressed in both mesenchymal stem cells and tumor cells. Targeted inhibition of NHE1 could induce differentiation of K562 leukemia cells. In the present paper we explored whether inhibition of NHE1 could induce differentiation of mesenchymal stem cells. Methods: MSCs were obtained from human umbilical cord and both the surface phenotype and functional characteristics were analyzed. Selective NHE1 inhibitor cariporide was used to treat human umbilical cord-derived mesenchymal stem cells (hUC-MSCs. The pHi and the differentiation of hUC-MSCs were compared upon cariporide treatment. The putative signaling pathway involved was also explored. Results: The pHi of hUC-MSCs was decreased upon cariporide treatment. Cariporide up-regulated the osteogenic differentiation of hUC-MSCs while the adipogenic differentiation was not affected. For osteogenic differentiation, β-catenin expression was up-regulated upon cariporide treatment. Conclusion: Decreased pHi induced by cariporide differentially contributes to hUC-MSCs differentiation.

  5. Effects of bone marrow or mesenchymal stem cell transplantation on oral mucositis (mouse) induced by fractionated irradiation

    International Nuclear Information System (INIS)

    Schmidt, M.; Haagen, J.; Noack, R.; Siegemund, A.; Gabriel, P.; Doerr, W.

    2014-01-01

    Oral mucositis is a severe and dose limiting early side effect of radiotherapy for head-and-neck tumors. This study was initiated to determine the effect of bone marrow- and mesenchymal stem cell transplantation on oral mucositis (mouse tongue model) induced by fractionated irradiation. Daily fractionated irradiation (5 x 3 Gy/week) was given over 1 (days 0-4) or 3 weeks (days 0-4, 7-11, 14-18). Each protocol was terminated (day 7 or 21) by graded test doses (5 dose groups, 10 animals each) in order to generate complete dose-effect curves. The incidence of mucosal ulceration, corresponding to confluent mucositis grade 3 (RTOG/EORTC), was analyzed as the primary, clinically relevant endpoint. Bone marrow or mesenchymal stem cells were transplanted intravenously at various time points within these fractionation protocols. Transplantation of 6 x 10 6 , but not of 3 x 10 6 bone marrow stem cells on day -1, +4, +8, +11 or +15 significantly increased the ED 50 values (dose, at which an ulcer is expected in 50% of the mice); transplantation on day +2, in contrast, was ineffective. Mesenchymal stem cell transplantation on day -1, 2 or +8 significantly, and on day +4 marginally increased the ED 50 values. Transplantation of bone marrow or mesenchymal stem cells has the potential to modulate radiation-induced oral mucositis during fractionated radiotherapy. The effect is dependent on the timing of the transplantation. The mechanisms require further investigation. (orig.)

  6. Tracking and Functional Characterization of Epithelial-Mesenchymal Transition and Mesenchymal Tumor Cells During Prostate Cancer Metastasis

    Science.gov (United States)

    Ruscetti, Marcus; Quach, Bill; Dadashian, Eman L.; Mulholland, David J.; Wu, Hong

    2015-01-01

    The epithelial-mesenchymal transition (EMT) has been postulated as a mechanism by which cancer cells acquire the invasive and stem-like traits necessary for distant metastasis. However, direct in vivo evidence for the role of EMT in the formation of cancer stem-like cells (CSC) and the metastatic cascade remains lacking. Here we report the first isolation and characterization of mesenchymal and EMT tumor cells, which harbor both epithelial and mesenchymal characteristics, in an autochthonous murine model of prostate cancer. By crossing the established Pb-Cre+/−;PtenL/L;KrasG12D/+ prostate cancer model with a vimentin-GFP reporter strain, generating CPKV mice, we were able to isolate epithelial, EMT and mesenchymal cancer cells based on expression of vimentin and EpCAM. CPKV mice (but not mice with Pten deletion alone) exhibited expansion of cells with EMT (EpCAM+/Vim-GFP+) and mesenchymal (EpCAM−/Vim-GFP+) characteristics at the primary tumor site and in circulation. These EMT and mesenchymal tumor cells displayed enhanced stemness and invasive character compared to epithelial tumor cells. Moreover, they displayed an enriched tumor-initiating capacity and could regenerate epithelial glandular structures in vivo, indicative of epithelia-mesenchyme plasticity. Interestingly, while mesenchymal tumor cells could persist in circulation and survive in the lung following intravenous injection, only epithelial and EMT tumor cells could form macrometastases. Our work extends the evidence that mesenchymal and epithelial states in cancer cells contribute differentially to their capacities for tumor initiation and metastatic seeding, respectively, and that EMT tumor cells exist with plasticity that can contribute to multiple stages of the metastatic cascade. PMID:25948589

  7. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... these lenses . "Most people believe that decorative lenses do not require the same level of care or ... Ophthalmologists APR 20, 2018 By Dan T. Gudgel Do you know what the difference is between ophthalmologists ...

  8. Contextualizing Intergroup Contact: Do Political Party Cues Enhance Contact Effects?

    DEFF Research Database (Denmark)

    Sønderskov, Kim Mannemar; Thomsen, Jens Peter Frølund

    2015-01-01

    This article examines intergroup contact effects in different political contexts. We expand on previous efforts of social psychologists by incorporating the messages of political parties as a contextual trigger of group membership awareness in contact situations. We argue that the focus among...... political parties on us-them categorizations heightens the awareness of group memberships. This focus in turn enhances the positive intergroup contact effect by stimulating majority members to perceive contacted persons as prototypical outgroup members. A multilevel analysis of 22 countries and almost 37......,000 individuals confirms that the ability of intergroup contact to reduce antiforeigner sentiment increases when political parties focus intensively on immigration issues and cultural differences. Specifically, both workplace contact and interethnic friendship become more effective in reducing antiforeigner...

  9. An approximate JKR solution for a general contact, including rough contacts

    Science.gov (United States)

    Ciavarella, M.

    2018-05-01

    In the present note, we suggest a simple closed form approximate solution to the adhesive contact problem under the so-called JKR regime. The derivation is based on generalizing the original JKR energetic derivation assuming calculation of the strain energy in adhesiveless contact, and unloading at constant contact area. The underlying assumption is that the contact area distributions are the same as under adhesiveless conditions (for an appropriately increased normal load), so that in general the stress intensity factors will not be exactly equal at all contact edges. The solution is simply that the indentation is δ =δ1 -√{ 2 wA‧ /P″ } where w is surface energy, δ1 is the adhesiveless indentation, A‧ is the first derivative of contact area and P‧‧ the second derivative of the load with respect to δ1. The solution only requires macroscopic quantities, and not very elaborate local distributions, and is exact in many configurations like axisymmetric contacts, but also sinusoidal waves contact and correctly predicts some features of an ideal asperity model used as a test case and not as a real description of a rough contact problem. The solution permits therefore an estimate of the full solution for elastic rough solids with Gaussian multiple scales of roughness, which so far was lacking, using known adhesiveless simple results. The result turns out to depend only on rms amplitude and slopes of the surface, and as in the fractal limit, slopes would grow without limit, tends to the adhesiveless result - although in this limit the JKR model is inappropriate. The solution would also go to adhesiveless result for large rms amplitude of roughness hrms, irrespective of the small scale details, and in agreement with common sense, well known experiments and previous models by the author.

  10. Quaternionic contact Einstein structures and the quaternionic contact Yamabe problem

    CERN Document Server

    Ivanov, Stefan; Vassilev, Dimiter

    2014-01-01

    A partial solution of the quaternionic contact Yamabe problem on the quaternionic sphere is given. It is shown that the torsion of the Biquard connection vanishes exactly when the trace-free part of the horizontal Ricci tensor of the Biquard connection is zero and this occurs precisely on 3-Sasakian manifolds. All conformal transformations sending the standard flat torsion-free quaternionic contact structure on the quaternionic Heisenberg group to a quaternionic contact structure with vanishing torsion of the Biquard connection are explicitly described. A "3-Hamiltonian form" of infinitesimal conformal automorphisms of quaternionic contact structures is presented.

  11. Dynamics of the Molten Contact Line

    Science.gov (United States)

    Sonin, Ain A.; Duthaler, Gregg; Liu, Michael; Torresola, Javier; Qiu, Taiqing

    1999-01-01

    materials- molten wax on solid wax, water on ice, and mercury on frozen mercury- which between them span a considerable range of the deposition/solidification similarity parameters. Correlations are obtained for the spreading velocity, spreading time scales, the spreading factor (i.e. ratio of deposited drop's final footprint radius and the drop's initial radius), post-spreading liquid oscillation amplitudes and time scales, and bulk solidification time scales. Duthaler carried out an experimental and theoretical investigation of the relationship between the liquid's apparent contact angle and the Capillary number Ca=mu U/sigma based on contact line speed, for molten materials spreading over subcooled solids. This relationship is required for modeling of melt spreading. We have adapted Voinov's methodology to the molten contact line and formulated a theoretical model for the Ca vs. contact angle relationship, based Schiaffino and Sonin#s (1997a,b) wedge-like solidification front model. With the solidification front angle taken from Schiaffino and Sonin, the model is in good agreement with the experimental results for Ca vs. contact angle. Duthaler also extended the experimental investigation of droplet deposition and contact line freezing to more materials, including solder on glass, solder on solder, water on ice, and molten microcrystalline wax on wax. The latter also included tests on inclined targets. Deposition tests have also been done with molten octacosane (C28H58) on various targets. An important objective of our program has been the development of micron-scale sensors for measuring the transient temperature at a point on the substrate surface as a molten contact line moves over it. The expectation is that this temperature history will yield a better understanding of the thermal process in the contact line region. The sensors are of the thermistor type, either 2.5 microns or 1.5 microns square, microfabricated with silicon-based technology on either pure silicon or

  12. [Contact glass tonometer].

    Science.gov (United States)

    Dekker, P W; Kanngiesser, H; Robert, Y C

    1996-05-01

    This paper presents a tonometer built into a contactlens, which allows to measure the eye-pressure and to perform ophthalmoscopy at the same time. Artificially induced changes of the eye-pressure and their influence on the visible fundus can now be checked simultaneously. The contactlens-tonometer (CGT) also is able to record continuously the pulse-curve, which can indicate any circulatory problem. So, the device is expected to give us additional diagnostic criteria of early glaucoma. Each ophthalmologyst in the field will be able to perform with this device a oculodynamometry in an easy way. By this it is possible to estimate the pressure-tolerance of the optic disk from glaucoma-patients. There have been taken some measurements on enucleated human eyes, comparing our device with a Statham-transducer in the vitreous. We found a good correlation. In a second step, we made measurements (65) on healthy volunteers, comparing the device with Perkins-Tonometry. We found a correlation (R = 0.58). The error of the measurements was about +/- 3 mm Hg. Considering both, the deviation of the Perkins-Tonometer with which our results were compared, and the fact of a good correlation (R = 0.999) in the study with the enucleated human eyes, we found that the contact-lens-tonometer measures the intraocular pressure exactly. In future studies, we want to analyze the dynamic component of the measurements.

  13. Contact sport and osteoarthritis.

    LENUS (Irish Health Repository)

    Molloy, Michael G

    2011-04-01

    Osteoarthritis (OA) is the most common joint disease in the world and the single largest cause of disability for those over 18 years. It affects more than twice as many people as does cardiac disease, and increases in incidence and prevalence with age. Animal and human studies have shown no evidence of increased risk of hip or knee OA with moderate exercise and in the absence of traumatic injury, sporting activity has a protective effect. One age-matched case control study found recreational runners who ran 12-14 miles per week for up to 40 years had no increase in radiological or symptomatic hip or knee OA. However, higher rates of hip OA occur in contact sports than in age-matched controls, with the highest rate in professional players. Soccer players with torn anterior cruciate ligaments (ACL) are more likely to develop knee OA than those with intact ACL. Early ACL repair reduces the risk of knee OA, but does not prevent it. Established injury prevention programmes have been refined to prevent injuries such as ACL rupture.

  14. Mesenchymal stem cells: cell biology and potential use in therapy

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Kristiansen, Malthe; Abdallah, Basem M

    2004-01-01

    Mesenchymal stem cells are clonogenic, non-haematopoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages e.g. osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages e.g. neuronal-like cells. Several methods...... are currently available for isolation of the mesenchymal stem cells based on their physical and immunological characteristics. Because of the ease of their isolation and their extensive differentiation potential, mesenchymal stem cells are among the first stem cell types to be introduced in the clinic. Recent...... studies have demonstrated that the life span of mesenchymal stem cells in vitro can be extended by increasing the levels of telomerase expression in the cells and thus allowing culture of large number of cells needed for therapy. In addition, it has been shown that it is possible to culture the cells...

  15. Labeling and Imaging Mesenchymal Stem Cells with Quantum Dots

    Science.gov (United States)

    Mesenchymal stem cells (MSCs) are multipotent cells with the potential to differentiate into bone, cartilage, adipose and muscle cells. Adult derived MSCs are being actively investigated because of their potential to be utilized for therapeutic cell-based transplantation. Methods...

  16. Research on human placenta-derived mesenchymal stem cells ...

    African Journals Online (AJOL)

    Research on human placenta-derived mesenchymal stem cells transfected with pIRES2-EGFP-VEGF165 using liposome. ... African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue ...

  17. Cryopreservation and revival of human mesenchymal stromal cells

    DEFF Research Database (Denmark)

    Haack-Sørensen, Mandana; Ekblond, Annette; Kastrup, Jens

    2016-01-01

    Cell-based therapy is a promising and innovative new treatment for different degenerative and autoimmune diseases, and mesenchymal stromal cells (MSCs) from the bone marrow have demonstrated great therapeutic potential due to their immunosuppressive and regenerative capacities. The establishment ...

  18. Cryopreservation and revival of mesenchymal stromal cells

    DEFF Research Database (Denmark)

    Haack-Sørensen, Mandana; Kastrup, Jens

    2011-01-01

    initiated. As there has been a precedent for the use of bone marrow stem cells in the treatment of hematological malignancies and ischemic heart diseases through randomized clinical safety and efficacy trials, the development of new therapies based on culture-expanded human mesenchymal stromal cells (MSCs......Over the past few years, the pace of preclinical stem cell research is astonishing and adult stem cells have become the subject of intense research. Due to the presence of promising supporting preclinical data, human clinical trials for stem cell regenerative treatment of various diseases have been......) opens up new possibilities for cell therapy. To facilitate these applications, cryopreservation and long-term storage of MSCs becomes an absolute necessity. As a result, optimization of this cryopreservation protocol is absolutely critical. The major challenge during cellular cryopreservation...

  19. Receptor control in mesenchymal stem cell engineering

    Science.gov (United States)

    Dalby, Matthew J.; García, Andrés J.; Salmeron-Sanchez, Manuel

    2018-03-01

    Materials science offers a powerful tool to control mesenchymal stem cell (MSC) growth and differentiation into functional phenotypes. A complex interplay between the extracellular matrix and growth factors guides MSC phenotypes in vivo. In this Review, we discuss materials-based bioengineering approaches to direct MSC fate in vitro and in vivo, mimicking cell-matrix-growth factor crosstalk. We first scrutinize MSC-matrix interactions and how the properties of a material can be tailored to support MSC growth and differentiation in vitro, with an emphasis on MSC self-renewal mechanisms. We then highlight important growth factor signalling pathways and investigate various materials-based strategies for growth factor presentation and delivery. Integrin-growth factor crosstalk in the context of MSC engineering is introduced, and bioinspired material designs with the potential to control the MSC niche phenotype are considered. Finally, we summarize important milestones on the road to MSC engineering for regenerative medicine.

  20. Mesenchymal Stem Cells: Angels or Demons?

    Directory of Open Access Journals (Sweden)

    Rebecca S. Y. Wong

    2011-01-01

    Full Text Available Mesenchymal stem cells (MSCs have been used in cell-based therapy in various disease conditions such as graft-versus-host and heart diseases, osteogenesis imperfecta, and spinal cord injuries, and the results have been encouraging. However, as MSC therapy gains popularity among practitioners and researchers, there have been reports on the adverse effects of MSCs especially in the context of tumour modulation and malignant transformation. These cells have been found to enhance tumour growth and metastasis in some studies and have been related to anticancer-drug resistance in other instances. In addition, various studies have also reported spontaneous malignant transformation of MSCs. The mechanism of the modulatory behaviour and the tumorigenic potential of MSCs, warrant urgent exploration, and the use of MSCs in patients with cancer awaits further evaluation. However, if MSCs truly play a role in tumour modulation, they can also be potential targets of cancer treatment.

  1. Mesenchymal stem cells: angels or demons?

    Science.gov (United States)

    Wong, Rebecca S Y

    2011-01-01

    Mesenchymal stem cells (MSCs) have been used in cell-based therapy in various disease conditions such as graft-versus-host and heart diseases, osteogenesis imperfecta, and spinal cord injuries, and the results have been encouraging. However, as MSC therapy gains popularity among practitioners and researchers, there have been reports on the adverse effects of MSCs especially in the context of tumour modulation and malignant transformation. These cells have been found to enhance tumour growth and metastasis in some studies and have been related to anticancer-drug resistance in other instances. In addition, various studies have also reported spontaneous malignant transformation of MSCs. The mechanism of the modulatory behaviour and the tumorigenic potential of MSCs, warrant urgent exploration, and the use of MSCs in patients with cancer awaits further evaluation. However, if MSCs truly play a role in tumour modulation, they can also be potential targets of cancer treatment.

  2. Endothelial-Mesenchymal Transition in Regenerative Medicine

    Directory of Open Access Journals (Sweden)

    Damian Medici

    2016-01-01

    Full Text Available Endothelial-mesenchymal transition (EndMT is a fundamental cellular mechanism that regulates embryonic development and diseases such as cancer and fibrosis. Recent developments in biomedical research have shown remarkable potential to harness the EndMT process for tissue engineering and regeneration. As an alternative to traditional or artificial stem cell therapies, EndMT may represent a safe method for engineering new tissues to treat degenerative diseases by mimicking a process that occurs in nature. This review discusses the signaling mechanisms and therapeutic inhibitors of EndMT, as well as the role of EndMT in development, disease, acquiring stem cell properties and generating connective tissues, and its potential as a novel mechanism for tissue regeneration.

  3. Mesenchymal stem cell therapy for laryngotracheal stenosis

    DEFF Research Database (Denmark)

    Jakobsen, Kathrine Kronberg; Grønhøj, Christian; Jensen, David H

    2017-01-01

    studies addressing the effect of MSC therapy on the airway. We assessed effect on inflammation, fibrosis, and MSC as a component in tissue engineering for treating defects in the airway. RESULTS: We identified eleven studies (n = 256 animals) from eight countries evaluating the effect of MSCs......BACKGROUND: Laryngotracheal stenosis (LTS) can be either congenital or acquired. Laryngeal stenosis is most often encountered after prolonged intubation. The mechanism for stenosis following intubation is believed to be hypertrophic scarring. Mesenchymal stem cells (MSCs) therapy has shown...... promising results in regenerative medicine. We aimed to systematically review the literature on MSC therapy for stenosis of the conductive airways. METHODS: PubMed, EMBASE, Google Scholar and the Cochrane Library were systematically searched from January 1980-January 2017 with the purpose of identifying all...

  4. The importance of contact quality

    DEFF Research Database (Denmark)

    van Bakel, Marian; Gerritsen, Marinel; van Oudenhoven, Jan Pieter

    Establishing contact between expatriates and a local host has been found to reap benefits with regard to Interaction Adjustment, Host National Social Support, Open-mindedness, and Social Initiative. This longitudinal study examines the role of the quality of contact for these four aspects....... Expatriates in the Netherlands were randomly divided into an experimental group (n = 33) of which 21 developed high-quality contact with their host, and a control group (n = 32) without host. The results show that contact quality plays an important role and suggest that the higher the quality of the contact......, the more benefit the expatriate experienced. Moreover, expatriates with low-quality contact did not experience a detrimental effect....

  5. Fibroblast growth factor signaling is required for early somatic gonad development in zebrafish.

    Science.gov (United States)

    Leerberg, Dena M; Sano, Kaori; Draper, Bruce W

    2017-09-01

    The vertebrate ovary and testis develop from a sexually indifferent gonad. During early development of the organism, primordial germ cells (the gamete lineage) and somatic gonad cells coalesce and begin to undergo growth and morphogenesis to form this bipotential gonad. Although this aspect of development is requisite for a fertile adult, little is known about the genetic regulation of early gonadogenesis in any vertebrate. Here, we provide evidence that fibroblast growth factor (Fgf) signaling is required for the early growth phase of a vertebrate bipotential gonad. Based on mutational analysis in zebrafish, we show that the Fgf ligand 24 (Fgf24) is required for proliferation, differentiation, and morphogenesis of the early somatic gonad, and as a result, most fgf24 mutants are sterile as adults. Additionally, we describe the ultrastructural elements of the early zebrafish gonad and show that distinct somatic cell populations can be identified soon after the gonad forms. Specifically, we show that fgf24 is expressed in an epithelial population of early somatic gonad cells that surrounds an inner population of mesenchymal somatic gonad cells that are in direct contact with the germ cells, and that fgf24 is required for stratification of the somatic tissue. Furthermore, based on gene expression analysis, we find that differentiation of the inner mesenchymal somatic gonad cells into functional cell types in the larval and early juvenile-stage gonad is dependent on Fgf24 signaling. Finally, we argue that the role of Fgf24 in zebrafish is functionally analogous to the role of tetrapod FGF9 in early gonad development.

  6. Primitive myxoid mesenchymal tumor of infancy in a preterm infant.

    Science.gov (United States)

    Lam, Joseph; Lara-Corrales, Irene; Cammisuli, Salvatore; Somers, Gino R; Pope, Elena

    2010-01-01

    Primitive myxoid mesenchymal tumor of infancy is a recently recognized entity that has been added to the differential diagnosis of myxoid tumors of the soft tissue. Few cases have been reported of this entity in the literature, but none presenting in a preterm infant. We present the case and clinical course of a preterm boy with a primitive myxoid mesenchymal tumor of infancy that occurred following excision of a congenital juvenile xanthogranuloma. © 2010 Wiley Periodicals, Inc.

  7. Mesenchymal Stem Cell Based Therapy for Prostate Cancer

    Science.gov (United States)

    2015-11-01

    Montero-Menei, C.; Menei, P. Mesenchymal Stem Cells as Cellular Vehicles for Delivery of Nanoparticles to Brain Tumors. Biomaterials 2010, 31, 8393... Stem Cells : Considerations for Regenerative Medicine Approaches. Tissue Eng. Part B. Rev. 2010, 16, 159–168. 55. Ellem, S. J.; Taylor, R. a.; Furic, L...Award Number: W81XWH-13-1-0304 TITLE: Mesenchymal Stem Cell -Based Therapy for Prostate Cancer PRINCIPAL INVESTIGATOR: John Isaacs CONTRACTING

  8. Contact Lens Related Corneal Ulcer

    OpenAIRE

    Loh, KY; Agarwal, P

    2010-01-01

    A corneal ulcer caused by infection is one of the major causes of blindness worldwide. One of the recent health concerns is the increasing incidence of corneal ulcers associated with contact lens user especially if the users fail to follow specific instruction in using their contact lenses. Risk factors associated with increased risk of contact lens related corneal ulcers are: overnight wear, long duration of continuous wear, lower socio-economic classes, smoking, dry eye and poor hygiene. Th...

  9. Emotional Satisfaction of Customer Contacts

    OpenAIRE

    Güngör, Hüseyin

    2007-01-01

    For marketing and customer services researchers and professionals who are interested in customer contacts, customer satisfaction and loyalty issues. Contact centers are playing a pivotal role in customer services of the 21st century. Nevertheless, despite their growing importance and presence, contact centers are increasingly becoming the center for customer frustration, and frequently associated with negative comments in the media. Therefore, this research explores the Emotional, Cognitive, ...

  10. Diagnosing Allergic Contact Dermatitis Through Elimination, Perception, Detection and Deduction.

    Science.gov (United States)

    Pongpairoj, Korbkarn; Puangpet, Pailin; Thaiwat, Supitchaya; McFadden, John P

    2017-10-01

    Several authors have commented upon the skills of detection required in making a diagnosis of allergic contact dermatitis. Here, we emphasise the search for clues in a systematic manner. We describe four stages as part of a systematic method for diagnosing allergic contact dermatitis. Firstly, elimination (or inclusion) of non-allergic diagnoses. Secondly, perception: the pre-patch test diagnosis and the 'three scenarios' principle. Thirdly, detection: optimising the sensitivity of the patch test process. Fourthly, deduction: diagnosing allergic contact dermatitis by associating the dermatitis with the allergen exposure. We further compare and contrast the pre-patch test history and examination with the markedly different one ('microhistory' and 'microexamination') used after patch testing. The importance of knowledge of contact dermatitis literature is emphasised with a review of recent publications. Finally, we also highlight the use of contact allergy profiling as an investigative tool in the diagnosis of allergic contact dermatitis.

  11. Non-contact ultrasound techniques

    International Nuclear Information System (INIS)

    Khazali Mohd Zin

    2001-01-01

    Non-contact ultrasound plays significant role in material characterisation and inspection. Unlike conventional ultrasonic techniques, non-contact ultrasonic is mostly applicable to areas where the former has its weaknesses and limitations. It is interesting to note that the non-contact ultrasonic technique has an important significant application in industry. The technique is signified by the fact that the object to be inspected is further away from the ultrasonic source, no couplant is needed and inconsistent pressure between the transducer and the specimen can be eliminated. The paper discusses some of the non-contact ultrasound technique and its applications. (Author)

  12. Occupational contact dermatitis in hairdressers

    DEFF Research Database (Denmark)

    Schwensen, Jakob F; Johansen, Jeanne Duus; Veien, Niels K

    2013-01-01

    BACKGROUND: Occupational contact dermatitis among hairdressers is frequent, owing to daily exposure to irritants and allergens. OBJECTIVES: To identify sensitization to the most common allergens associated with the occupation of hairdressing. METHODS: Patch test results of 399 hairdressers and 1995...... matched controls with contact dermatitis, registered by the Danish Contact Dermatitis Group between January 2002 and December 2011, were analysed. All patients were patch tested with the European baseline series, and hairdressers were additionally tested with the hairdressing series. RESULTS: Occupational...... contact dermatitis (p dermatitis was less commonly observed among hairdressers (21.3%) than among controls (29.4%) (p 

  13. Sub-circuits of a gene regulatory network control a developmental epithelial-mesenchymal transition.

    Science.gov (United States)

    Saunders, Lindsay R; McClay, David R

    2014-04-01

    Epithelial-mesenchymal transition (EMT) is a fundamental cell state change that transforms epithelial to mesenchymal cells during embryonic development, adult tissue repair and cancer metastasis. EMT includes a complex series of intermediate cell state changes including remodeling of the basement membrane, apical constriction, epithelial de-adhesion, directed motility, loss of apical-basal polarity, and acquisition of mesenchymal adhesion and polarity. Transcriptional regulatory state changes must ultimately coordinate the timing and execution of these cell biological processes. A well-characterized gene regulatory network (GRN) in the sea urchin embryo was used to identify the transcription factors that control five distinct cell changes during EMT. Single transcription factors were perturbed and the consequences followed with in vivo time-lapse imaging or immunostaining assays. The data show that five different sub-circuits of the GRN control five distinct cell biological activities, each part of the complex EMT process. Thirteen transcription factors (TFs) expressed specifically in pre-EMT cells were required for EMT. Three TFs highest in the GRN specified and activated EMT (alx1, ets1, tbr) and the 10 TFs downstream of those (tel, erg, hex, tgif, snail, twist, foxn2/3, dri, foxb, foxo) were also required for EMT. No single TF functioned in all five sub-circuits, indicating that there is no EMT master regulator. Instead, the resulting sub-circuit topologies suggest EMT requires multiple simultaneous regulatory mechanisms: forward cascades, parallel inputs and positive-feedback lock downs. The interconnected and overlapping nature of the sub-circuits provides one explanation for the seamless orchestration by the embryo of cell state changes leading to successful EMT.

  14. Micromechanical contact stiffness devices and application for calibrating contact resonance atomic force microscopy

    Science.gov (United States)

    Rosenberger, Matthew R.; Chen, Sihan; Prater, Craig B.; King, William P.

    2017-01-01

    This paper reports the design, fabrication, and characterization of micromechanical devices that can present an engineered contact stiffness to an atomic force microscope (AFM) cantilever tip. These devices allow the contact stiffness between the AFM tip and a substrate to be easily and accurately measured, and can be used to calibrate the cantilever for subsequent mechanical property measurements. The contact stiffness devices are rigid copper disks of diameters 2-18 μm integrated onto a soft silicone substrate. Analytical modeling and finite element simulations predict the elastic response of the devices. Measurements of tip-sample interactions during quasi-static force measurements compare well with modeling simulation, confirming the expected elastic response of the devices, which are shown to have contact stiffness 32-156 N m-1. To demonstrate one application, we use the disk sample to calibrate three resonant modes of a U-shaped AFM cantilever actuated via Lorentz force, at approximately 220, 450, and 1200 kHz. We then use the calibrated cantilever to determine the contact stiffness and elastic modulus of three polymer samples at these modes. The overall approach allows cantilever calibration without prior knowledge of the cantilever geometry or its resonance modes, and could be broadly applied to both static and dynamic measurements that require AFM calibration against a known contact stiffness.

  15. Tracking social contact networks with online respondent-driven detection : who recruits whom?

    NARCIS (Netherlands)

    Stein, Mart L.; van der Heijden, P.G.M.; Buskens, V.W.; van Steenbergen, Jim E.; Bengtsson, Linus; Koppeschaar, Carl E.; Thorson, Anna E.; Kretzschmar, Mirjam E. E.

    2015-01-01

    Background: Transmission of respiratory pathogens in a population depends on the contact network patterns of individuals. To accurately understand and explain epidemic behaviour information on contact networks is required, but only limited empirical data is available. Online respondent-driven

  16. Tracking social contact networks with online respondent-driven detection : who recruits whom?

    NARCIS (Netherlands)

    Stein, Mart L; van der Heijden, Peter G M; Buskens, Vincent; van Steenbergen, Jim E; Bengtsson, Linus; Koppeschaar, Carl E; Thorson, Anna; Kretzschmar, MEE

    2015-01-01

    BACKGROUND: Transmission of respiratory pathogens in a population depends on the contact network patterns of individuals. To accurately understand and explain epidemic behaviour information on contact networks is required, but only limited empirical data is available. Online respondent-driven

  17. On accurate determination of contact angle

    Science.gov (United States)

    Concus, P.; Finn, R.

    1992-01-01

    Methods are proposed that exploit a microgravity environment to obtain highly accurate measurement of contact angle. These methods, which are based on our earlier mathematical results, do not require detailed measurement of a liquid free-surface, as they incorporate discontinuous or nearly-discontinuous behavior of the liquid bulk in certain container geometries. Physical testing is planned in the forthcoming IML-2 space flight and in related preparatory ground-based experiments.

  18. Mesenchymal Stromal Cell Phenotype is not Influenced by Confluence during Culture Expansion

    DEFF Research Database (Denmark)

    Haack-Sørensen, Mandana; Hansen, Susanne Kofoed; Hansen, Louise

    2013-01-01

    BACKGROUND: Accumulating preclinical and clinical evidence indicates that human mesenchymal stromal cells (MSCs) are good candidates for cell therapy. For clinical applications of MSCs extensive in vitro expansion is required to obtain an adequate number of cells. It is evident that the pursuit...... differentiation. This phenotype persisted independent of increasing cell densities. DISCUSSION: These data demonstrate that MSC characteristics and plasticity can be maintained during culture expansion from bone marrow mononuclear cells to MSCs and that a homogeneous phenotype of undifferentiated MSCs which...... persists independent of cell density can be used for clinical therapies....

  19. Contact mechanics of reverse engineered distal humeral hemiarthroplasty implants.

    Science.gov (United States)

    Willing, Ryan; King, Graham J W; Johnson, James A

    2015-11-26

    Erosion of articular cartilage is a concern following distal humeral hemiarthroplasty, because native cartilage surfaces are placed in contact with stiff metallic implant components, which causes decreases in contact area and increases in contact stresses. Recently, reverse engineered implants have been proposed which are intended to promote more natural contact mechanics by reproducing the native bone or cartilage shape. In this study, finite element modeling is used in order to calculate changes in cartilage contact areas and stresses following distal humeral hemiarthroplasty with commercially available and reverse engineered implant designs. At the ulna, decreases in contact area were -34±3% (p=0.002), -27±1% (pengineered and cartilage reverse engineered designs, respectively. Peak contact stresses increased by 461±57% (p=0.008), 387±127% (p=0.229) and 165±16% (p=0.003). At the radius, decreases in contact area were -21±3% (p=0.013), -13±2% (p0.999), 241±32% (p=0.010) and 61±10% (p=0.021). Between the three different implant designs, the cartilage reverse engineered design yielded the largest contact areas and lowest contact stresses, but was still unable to reproduce the contact mechanics of the native joint. These findings align with a growing body of evidence indicating that although reverse engineered hemiarthroplasty implants can provide small improvements in contact mechanics when compared with commercially available designs, further optimization of shape and material properties is required in order reproduce native joint contact mechanics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Fabricating customized hydrogel contact lens

    Science.gov (United States)

    Childs, Andre; Li, Hao; Lewittes, Daniella M.; Dong, Biqin; Liu, Wenzhong; Shu, Xiao; Sun, Cheng; Zhang, Hao F.

    2016-10-01

    Contact lenses are increasingly used in laboratories for in vivo animal retinal imaging and pre-clinical studies. The lens shapes often need modification to optimally fit corneas of individual test subjects. However, the choices from commercially available contact lenses are rather limited. Here, we report a flexible method to fabricate customized hydrogel contact lenses. We showed that the fabricated hydrogel is highly transparent, with refractive indices ranging from 1.42 to 1.45 in the spectra range from 400 nm to 800 nm. The Young’s modulus (1.47 MPa) and hydrophobicity (with a sessile drop contact angle of 40.5°) have also been characterized experimentally. Retinal imaging using optical coherence tomography in rats wearing our customized contact lenses has the quality comparable to the control case without the contact lens. Our method could significantly reduce the cost and the lead time for fabricating soft contact lenses with customized shapes, and benefit the laboratorial-used contact lenses in pre-clinical studies.

  1. Emotional Satisfaction of Customer Contacts

    NARCIS (Netherlands)

    Güngör, Hüseyin

    2007-01-01

    For marketing and customer services researchers and professionals who are interested in customer contacts, customer satisfaction and loyalty issues. Contact centers are playing a pivotal role in customer services of the 21st century. Nevertheless, despite their growing importance and presence,

  2. Journal of Business Research: Contact

    African Journals Online (AJOL)

    Principal Contact. Goski Alabi Mrs Institute of Professional Studies (IPS) P. 0 Box 149 Institute Of Professional Studies (IPS) Legon, Accra Ghana Phone: +233 24 64 52798. Fax: +233 21 513539. Email: goskia@yahoo.com. Support Contact. Anthony Afeadie. Phone: +233 21 500171. Email: ipsjournal@yahoo.com.

  3. Aluminum break-point contacts

    NARCIS (Netherlands)

    Heinemann, Martina; Groot, R.A. de

    1997-01-01

    Ab initio molecular dynamics is used to study the contribution of a single Al atom to an aluminum breakpoint contact during the final stages of breaking and the initial stages of the formation of such a contact. A hysteresis effect is found in excellent agreement with experiment and the form of the

  4. Contact Allergy to Neem Oil.

    NARCIS (Netherlands)

    de Groot, Anton; Jagtman, Berend A; Woutersen, Marjolijn

    2018-01-01

    A case of allergic contact dermatitis from neem oil is presented. Neem oil (synonyms: Melia azadirachta seed oil [INCI name], nim oil, margosa oil) is a vegetable (fixed) oil obtained from the seed of the neem tree Azadirachta indica by cold pressing. Contact allergy to neem oil has been described

  5. Body contact and body language

    DEFF Research Database (Denmark)

    Winther, Helle

    2008-01-01

    and the boundaries between self and world. In western societies, the modern premises for contact are in some ways developing from close contact to virtual communication. With this breadth of perspective in mind, the ques­tion is whether conscious and experimental work with body contact and body language in move......­ment psychology and education provide potential for intense personal develop­ment as well as for social and cultural learning processes. This performative research project originates from the research project entitled, Movement Psy­chol­ogy: The Language of the Body and the Psy­chol­ogy of Movement based......Body contact and body language are unique and existential and, although culturally dependent and socially embodied, they are also universal communication forms. For small children all over the world, warm, close and nourishing body contact is fundamental to their embodied experi­ence of themselves...

  6. Role of Firing Temperature, Sheet Resistance, and Contact Area in Contact Formation on Screen-Printed Metal Contact of Silicon Solar Cell

    Science.gov (United States)

    Ahmad, Samir Mahmmod; Leong, Cheow Siu; Sopian, K.; Zaidi, Saleem H.

    2018-03-01

    Formation of an Ohmic contact requires a suitable firing temperature, appropriate doping profile, and contact dimensions within resolution limits of the screen-printing process. In this study, the role of the peak firing temperature in standard rapid thermal annealing (RTA) six-zone conveyor belt furnace (CBF) and two inexpensive alternate RTA systems [a custom-designed, three-zone, 5″-diameter quartz tube furnace (QTF) and a tabletop, 3″-diameter rapid thermal processing (RTP)] has been investigated. In addition, the role of sheet resistance and contact area in achieving low-resistance ohmic contacts has been examined. Electrical measurements of ohmic contacts between silver paste/ n +-emitter layer with varying sheet resistances and aluminum paste/ p-doped wafer were carried out in transmission line method configuration. Experimental measurements of the contact resistivity ( ρ c) exhibited the lowest values for CBF at 0.14 mΩ cm2 for Ag and 100 mΩ cm2 for Al at a peak firing temperature of 870°C. For the QTF configuration, lowest measured contact resistivities were 3.1 mΩ cm2 for Ag and 74.1 mΩ cm2 for Al at a peak firing temperature of 925°C. Finally, for the RTP configuration, lowest measured contact resistivities were 1.2 mΩ cm2 for Ag and 68.5 mΩ cm2 for Al at a peak firing temperature of 780°C. The measured contact resistivity exhibits strong linear dependence on sheet resistance. The contact resistivity for Ag decreases with contact area, while for Al the opposite behavior is observed.

  7. Evaluation of residue-residue contact prediction in CASP10

    KAUST Repository

    Monastyrskyy, Bohdan

    2013-08-31

    We present the results of the assessment of the intramolecular residue-residue contact predictions from 26 prediction groups participating in the 10th round of the CASP experiment. The most recently developed direct coupling analysis methods did not take part in the experiment likely because they require a very deep sequence alignment not available for any of the 114 CASP10 targets. The performance of contact prediction methods was evaluated with the measures used in previous CASPs (i.e., prediction accuracy and the difference between the distribution of the predicted contacts and that of all pairs of residues in the target protein), as well as new measures, such as the Matthews correlation coefficient, the area under the precision-recall curve and the ranks of the first correctly and incorrectly predicted contact. We also evaluated the ability to detect interdomain contacts and tested whether the difficulty of predicting contacts depends upon the protein length and the depth of the family sequence alignment. The analyses were carried out on the target domains for which structural homologs did not exist or were difficult to identify. The evaluation was performed for all types of contacts (short, medium, and long-range), with emphasis placed on long-range contacts, i.e. those involving residues separated by at least 24 residues along the sequence. The assessment suggests that the best CASP10 contact prediction methods perform at approximately the same level, and comparably to those participating in CASP9.

  8. Visual method for detecting critical damage in railway contact strips

    Science.gov (United States)

    Judek, S.; Skibicki, J.

    2018-05-01

    Ensuring an uninterrupted supply of power in the electric traction is vital for the safety of this important transport system. For this purpose, monitoring and diagnostics of the technical condition of the vehicle’s power supply elements are becoming increasingly common. This paper presents a new visual method for detecting contact strip damage, based on measurement and analysis of the movement of the overhead contact line (OCL) wire. A measurement system configuration with a 2D camera was proposed. The experimental method has shown that contact strips damage can be detected by transverse displacement signal analysis. It has been proven that the velocity signal numerically established on that basis has a comparable level in the case of identical damage, regardless of its location on the surface of the contact strip. The proposed method belongs to the group of contact-less measurements, so it does not require interference with the structure of the catenary network nor the mounting of sensors in its vicinity. Measurement of displacements of the contact wire in 2D space makes it possible to combine the functions of existing diagnostic stands assessing the correctness of the mean contact force control adjustment of the current collector with the elements of the contact strip diagnostics, which involves detecting their damage which may result in overhead contact line rupture.

  9. Collagen cross-linking by adipose-derived mesenchymal stromal cells and scar-derived mesenchymal cells: Are mesenchymal stromal cells involved in scar formation?

    NARCIS (Netherlands)

    Bogaerdt, van den A.J.; Veen, van der A.G.; Zuijlen, van P.P.; Reijnen, L.; Verkerk, M.; Bank, R.A.; Middelkoop, E.; Ulrich, M.

    2009-01-01

    In this work, different fibroblast-like (mesenchymal) cell populations that might be involved in wound healing were characterized and their involvement in scar formation was studied by determining collagen synthesis and processing. Depending on the physical and mechanical properties of the tissues,

  10. Collagen cross-linking by adipose-derived mesenchymal stromal cells and scar-derived mesenchymal cells : Are mesenchymal stromal cells involved in scar formation?

    NARCIS (Netherlands)

    van den Bogaerdt, Antoon J.; van der Veen, Vincent C.; van Zuijlen, Paul P. M.; Reijnen, Linda; Verkerk, Michelle; Bank, Ruud A.; Middelkoop, Esther; Ulrich, Magda M. W.

    2009-01-01

    In this work, different fibroblast-like (mesenchymal) cell populations that might be involved in wound healing were characterized and their involvement in scar formation was studied by determining collagen synthesis and processing. Depending on the physical and mechanical properties of the tissues,

  11. Mesenchymal stem cells in cartilage regeneration.

    Science.gov (United States)

    Savkovic, Vuk; Li, Hanluo; Seon, Jong-Keun; Hacker, Michael; Franz, Sandra; Simon, Jan-Christoph

    2014-01-01

    Articular cartilage provides life-long weight-bearing and mechanical lubrication with extraordinary biomechanical performance and simple structure. However, articular cartilage is apparently vulnerable to multifactorial damage and insufficient to self-repair, isolated in articular capsule without nerves or blood vessels. Osteoarthritis (OA) is known as a degenerative articular cartilage deficiency progressively affecting large proportion of the world population, and restoration of hyaline cartilage is clinical challenge to repair articular cartilage lesion and recreate normal functionality over long period. Mesenchymal stem cells (MSC) are highly proliferative and multipotent somatic cells that are able to differentiate mesoderm-derived cells including chondrocytes and osteoblasts. Continuous endeavors in basic research and preclinical trial have achieved promising outcomes in cartilage regeneration using MSCs. This review focuses on rationale and technologies of MSC-based hyaline cartilage repair involving tissue engineering, 3D biomaterials and growth factors. By comparing conventional treatment and current research progress, we describe insights of advantage and challenge in translation and application of MSC-based chondrogenesis for OA treatment.

  12. Application of mesenchymal stem cells in paediatrics

    Directory of Open Access Journals (Sweden)

    Wawryk-Gawda Ewelina

    2017-09-01

    Full Text Available Mesenchymal stem cells (MSC were described by Friedenstein in the 1970s as being a group of bone marrow non-hematopoietic cells that are the source of fibroblasts. Since then, knowledge about the therapeutic potential of MSCs has significantly increased. MSCs are currently used for the treatment of many diseases, both in adults and children. MSCs are used successfully in the case of autoimmune diseases, including rheumatic diseases, diabetes mellitus type 1, gastroenterological and neurological diseases. Moreover, treatment of such organ disorders as damage or hypoxia through application of MSC therapy has shown to be satisfactory. In addition, there are some types of congenital disorders, including osteogenesis imperfecta and Spinal Muscular Atrophy, that may be treated with cellular therapy. Most studies showed no other adverse effects than fever. Our study is an analysis that particularly focuses on the registered trials and results of MSCs application to under 18 patients with acute, chronic, recurrent, resistance and corticosteroids types of Graft-versus-Host Disease (GvHD. Stem cells currently play an important role in the treatment of many diseases. Long-term studies conducted on animals have shown that cell therapy is both effective and safe. The number of indications for use of these cells in the course of treatment of people is constantly increasing. The results of subsequent studies provide important data justifying the application of MSCs in the course of treatment of many diseases whose treatment is ineffective when utilizing other approaches.

  13. Gut Mesenchymal Stromal Cells in Immunity

    Directory of Open Access Journals (Sweden)

    Valeria Messina

    2017-01-01

    Full Text Available Mesenchymal stromal cells (MSCs, first found in bone marrow (BM, are the structural architects of all organs, participating in most biological functions. MSCs possess tissue-specific signatures that allow their discrimination according to their origin and location. Among their multiple functions, MSCs closely interact with immune cells, orchestrating their activity to maintain overall homeostasis. The phenotype of tissue MSCs residing in the bowel overlaps with myofibroblasts, lining the bottom walls of intestinal crypts (pericryptal or interspersed within intestinal submucosa (intercryptal. In Crohn’s disease, intestinal MSCs are tightly stacked in a chronic inflammatory milieu, which causes their enforced expression of Class II major histocompatibility complex (MHC. The absence of Class II MHC is a hallmark for immune-modulator and tolerogenic properties of normal MSCs and, vice versa, the expression of HLA-DR is peculiar to antigen presenting cells, that is, immune-activator cells. Interferon gamma (IFNγ is responsible for induction of Class II MHC expression on intestinal MSCs. The reversal of myofibroblasts/MSCs from an immune-modulator to an activator phenotype in Crohn’s disease results in the formation of a fibrotic tube subverting the intestinal structure. Epithelial metaplastic areas in this context can progress to dysplasia and cancer.

  14. Transcriptional networks in epithelial-mesenchymal transition.

    Directory of Open Access Journals (Sweden)

    Christo Venkov

    Full Text Available Epithelial-mesenchymal transition (EMT changes polarized epithelial cells into migratory phenotypes associated with loss of cell-cell adhesion molecules and cytoskeletal rearrangements. This form of plasticity is seen in mesodermal development, fibroblast formation, and cancer metastasis.Here we identify prominent transcriptional networks active during three time points of this transitional process, as epithelial cells become fibroblasts. DNA microarray in cultured epithelia undergoing EMT, validated in vivo, were used to detect various patterns of gene expression. In particular, the promoter sequences of differentially expressed genes and their transcription factors were analyzed to identify potential binding sites and partners. The four most frequent cis-regulatory elements (CREs in up-regulated genes were SRY, FTS-1, Evi-1, and GC-Box, and RNA inhibition of the four transcription factors, Atf2, Klf10, Sox11, and SP1, most frequently binding these CREs, establish their importance in the initiation and propagation of EMT. Oligonucleotides that block the most frequent CREs restrain EMT at early and intermediate stages through apoptosis of the cells.Our results identify new transcriptional interactions with high frequency CREs that modulate the stability of cellular plasticity, and may serve as targets for modulating these transitional states in fibroblasts.

  15. Mesenchymal Wnt/β-catenin signaling limits tooth number.

    Science.gov (United States)

    Järvinen, Elina; Shimomura-Kuroki, Junko; Balic, Anamaria; Jussila, Maria; Thesleff, Irma

    2018-02-21

    Tooth agenesis is one of the predominant developmental anomalies in humans, usually affecting the permanent dentition generated by sequential tooth formation and, in most cases, caused by mutations perturbing epithelial Wnt/β-catenin signaling. In addition, loss-of-function mutations in the Wnt feedback inhibitor AXIN2 lead to human tooth agenesis. We have investigated the functions of Wnt/β-catenin signaling during sequential formation of molar teeth using mouse models. Continuous initiation of new teeth, which is observed after genetic activation of Wnt/β-catenin signaling in the oral epithelium, was accompanied by enhanced expression of Wnt antagonists and a downregulation of Wnt/β-catenin signaling in the dental mesenchyme. Genetic and pharmacological activation of mesenchymal Wnt/β-catenin signaling negatively regulated sequential tooth formation, an effect partly mediated by Bmp4. Runx2 , a gene whose loss-of-function mutations result in sequential formation of supernumerary teeth in the human cleidocranial dysplasia syndrome, suppressed the expression of Wnt inhibitors Axin2 and Drapc1 in dental mesenchyme. Our data indicate that increased mesenchymal Wnt signaling inhibits the sequential formation of teeth, and suggest that Axin2 / Runx2 antagonistic interactions modulate the level of mesenchymal Wnt/β-catenin signaling, underlying the contrasting dental phenotypes caused by human AXIN2 and RUNX2 mutations. © 2018. Published by The Company of Biologists Ltd.

  16. Effect of silver nanoparticles on human mesenchymal stem cell differentiation

    Directory of Open Access Journals (Sweden)

    Christina Sengstock

    2014-11-01

    Full Text Available Background: Silver nanoparticles (Ag-NP are one of the fastest growing products in nano-medicine due to their enhanced antibacterial activity at the nanoscale level. In biomedicine, hundreds of products have been coated with Ag-NP. For example, various medical devices include silver, such as surgical instruments, bone implants and wound dressings. After the degradation of these materials, or depending on the coating technique, silver in nanoparticle or ion form can be released and may come into close contact with tissues and cells. Despite incorporation of Ag-NP as an antibacterial agent in different products, the toxicological and biological effects of silver in the human body after long-term and low-concentration exposure are not well understood. In the current study, we investigated the effects of both ionic and nanoparticulate silver on the differentiation of human mesenchymal stem cells (hMSCs into adipogenic, osteogenic and chondrogenic lineages and on the secretion of the respective differentiation markers adiponectin, osteocalcin and aggrecan.Results: As shown through laser scanning microscopy, Ag-NP with a size of 80 nm (hydrodynamic diameter were taken up into hMSCs as nanoparticulate material. After 24 h of incubation, these Ag-NP were mainly found in the endo-lysosomal cell compartment as agglomerated material. Cytotoxicity was observed for differentiated or undifferentiated hMSCs treated with high silver concentrations (≥20 µg·mL−1 Ag-NP; ≥1.5 µg·mL−1 Ag+ ions but not with low-concentration treatments (≤10 µg·mL−1 Ag-NP; ≤1.0 µg·mL−1 Ag+ ions. Subtoxic concentrations of Ag-NP and Ag+ ions impaired the adipogenic and osteogenic differentiation of hMSCs in a concentration-dependent manner, whereas chondrogenic differentiation was unaffected after 21 d of incubation. In contrast to aggrecan, the inhibitory effect of adipogenic and osteogenic differentiation was confirmed by a decrease in the secretion of

  17. Glial origin of mesenchymal stem cells in a tooth model system

    NARCIS (Netherlands)

    Kaukua, Nina; Shahidi, Maryam Khatibi; Konstantinidou, Chrysoula; Dyachuk, Vyacheslav; Kaucka, Marketa; Furlan, Alessandro; An, Zhengwen; Wang, Longlong; Hultman, Isabell; Ahrlund-Richter, Lars; Blom, Hans; Brismar, Hjalmar; Lopes, Natalia Assaife; Pachnis, Vassilis; Suter, Ueli; Clevers, Hans; Thesleff, Irma; Sharpe, Paul; Ernfors, Patrik; Fried, Kaj; Adameyko, Igor

    2014-01-01

    Mesenchymal stem cells occupy niches in stromal tissues where they provide sources of cells for specialized mesenchymal derivatives during growth and repair. The origins of mesenchymal stem cells have been the subject of considerable discussion, and current consensus holds that perivascular cells

  18. Impact of the shape of geological contact on mining losses in the process of near-contact zone development

    Directory of Open Access Journals (Sweden)

    Г. С. Курчин

    2017-03-01

    Full Text Available In Russia development of mineral resources is carried out on a truly grand scale, and mining industry is in its essence a basic sector, supporting and facilitating the development of national economy. It predetermines the need of safe and responsible attitude towards riches of our subsoil – mineral resources. With this in mind, one of the key requirements to extraction technologies is minimization of mining losses and ore dilution.The biggest ore losses in the mining block take place in the process of development of contact areas between the ore body and surrounding rocks, due to differences between development pattern and surface of geological contact. Complexity of the contact between ore and surrounding rocks is traditionally characterized by so called «stochastic contact zone». Technological difficulty of extracting ore from the ore – wallrock contact is determined by volatility of geometric parameters in «stochastic contact zone» in the plane of geological contact.Current paper focuses on the issues of standard-setting for mining losses and ore dilution in the process of near-contact zone development. A method is suggested to estimate standard values of losses and ore dilution in stochastic zones. Authors have developed an algorithm of defining the shape of the contact. In the stochastic zone the contact can have a rectangular, sinusoidal, serrate and straight-line shapes. Research has established a relation between the contact shape and amounts of mining losses and ore dilution, formulas to calculate standard values are presented. Using suggested method, standard values for contact ore losses can be obtained in a quicker and more reliable way.

  19. Scalable algorithms for contact problems

    CERN Document Server

    Dostál, Zdeněk; Sadowská, Marie; Vondrák, Vít

    2016-01-01

    This book presents a comprehensive and self-contained treatment of the authors’ newly developed scalable algorithms for the solutions of multibody contact problems of linear elasticity. The brand new feature of these algorithms is theoretically supported numerical scalability and parallel scalability demonstrated on problems discretized by billions of degrees of freedom. The theory supports solving multibody frictionless contact problems, contact problems with possibly orthotropic Tresca’s friction, and transient contact problems. It covers BEM discretization, jumping coefficients, floating bodies, mortar non-penetration conditions, etc. The exposition is divided into four parts, the first of which reviews appropriate facets of linear algebra, optimization, and analysis. The most important algorithms and optimality results are presented in the third part of the volume. The presentation is complete, including continuous formulation, discretization, decomposition, optimality results, and numerical experimen...

  20. Research in Hospitality Management: Contact

    African Journals Online (AJOL)

    Principal Contact. Dr Sjoerd A Gehrels Editor-in-Chief Stenden Hotel Management School, Academy of International Hospitality Research, Leeuwarden, The Netherlands Email: sjoerd.gehrels@stenden.com ...

  1. EPA Alternative Dispute Resolution Contacts

    Science.gov (United States)

    The success of EPA's ADR efforts depends on a network of talented and experienced professionals in Headquarters offices and EPA Regions. For Agency-wide ADR information, please contact the Conflict Prevention and Resolution Center.

  2. Tribological coatings: contact mechanisms and selection

    International Nuclear Information System (INIS)

    Matthews, A; Franklin, S; Holmberg, K

    2007-01-01

    This paper, which forms part of a special issue of this journal marking a 25th year anniversary in tribology, aims to provide an appraisal of key issues in coating tribology over that period. Two main inter-related strands are emphasized. One is the continuing move down the length scale in terms of the fundamental understanding of tribological contacts. This has been particularly useful in aiding the development of new coatings by identifying their property requirements at different scale levels. A second strand relates to the ongoing imperative to be able to design and select coatings to meet practical friction and wear requirements. This selection problem requires a robust methodology, and one such is elaborated in the paper, which takes account of the requirements of different types of tribological contacts and uses a combination of theoretical and empirical information. Challenges still remain in this regard, and the paper seeks to provide a basis for further developments to improve coatings and to ensure their effective selection

  3. Metal semiconductor contacts and devices

    CERN Document Server

    Cohen, Simon S; Einspruch, Norman G

    1986-01-01

    VLSI Electronics Microstructure Science, Volume 13: Metal-Semiconductor Contacts and Devices presents the physics, technology, and applications of metal-semiconductor barriers in digital integrated circuits. The emphasis is placed on the interplay among the theory, processing, and characterization techniques in the development of practical metal-semiconductor contacts and devices.This volume contains chapters that are devoted to the discussion of the physics of metal-semiconductor interfaces and its basic phenomena; fabrication procedures; and interface characterization techniques, particularl

  4. Embodied Archives as Contact Zones

    Directory of Open Access Journals (Sweden)

    Judit Vidiella

    2015-02-01

    Full Text Available This article proposes a reflection about affective politics from locating some theoretical and conceptual genealogies like «emotion», «affection», «zones of contact»…, that understand them as action and force fields. These contributions allow us to rethink the relation of affects with politics and strategies of archive linked to performance, and understood as zones of friction, collision, circulation and contact: performative writing, repertoire, memes…

  5. Resveratrol augments the canonical Wnt signaling pathway in promoting osteoblastic differentiation of multipotent mesenchymal cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Haibin; Shang, Linshan; Li, Xi; Zhang, Xiyu; Gao, Guimin; Guo, Chenhong; Chen, Bingxi; Liu, Qiji [Key Laboratory of Experimental Teratology, MOE, Institute of Molecular Medicine and Genetics, Shandong University, 44 Wen Hua Xi Lu, Jinan, Shandong 250012 (China); Gong, Yaoqin, E-mail: yxg8@sdu.edu.cn [Key Laboratory of Experimental Teratology, MOE, Institute of Molecular Medicine and Genetics, Shandong University, 44 Wen Hua Xi Lu, Jinan, Shandong 250012 (China); Shao, Changshun, E-mail: shao@biology.rutgers.edu [Key Laboratory of Experimental Teratology, MOE, Institute of Molecular Medicine and Genetics, Shandong University, 44 Wen Hua Xi Lu, Jinan, Shandong 250012 (China); Department of Genetics, Rutgers University, Piscataway, NJ 08854 (United States)

    2009-10-15

    Resveratrol has been shown to possess many health-benefiting effects, including the promotion of bone formation. In this report we investigated the mechanism by which resveratrol promotes osteoblastic differentiation from pluripotent mesenchymal cells. Since Wnt signaling is well documented to induce osteoblastogenesis and bone formation, we characterized the factors involved in Wnt signaling in response to resveratrol treatment. Resveratrol treatment of mesenchymal cells led to an increase in stabilization and nuclear accumulation of {beta}-catenin dose-dependently and time-dependently. As a consequence of the increased nuclear accumulation of {beta}-catenin, the ability to activate transcription of {beta}-catenin-TCF/LEF target genes that are required for osteoblastic differentiation was upregulated. However, resveratrol did not affect the initial step of the Wnt signaling pathway, as resveratrol was as effective in upregulating the activity of {beta}-catenin in cells in which Lrp5 was knocked down as in control cells. In addition, while conditioned medium enriched in Wnt signaling antagonist Dkk1 was able to inhibit Wnt3a-induced {beta}-catenin upregulation, this inhibitory effect can be abolished in resveratrol-treated cells. Furthermore, we showed that the level of glycogen synthase kinase 3{beta} (GSK-3{beta}), which phosphorylates and destabilizes {beta}-catenin, was reduced in response to resveratrol treatment. The phosphorylation of GSK-3{beta} requires extracellular signal-regulated kinase (ERK)1/2. Together, our data indicate that resveratrol promotes osteoblastogenesis and bone formation by augmenting Wnt signaling.

  6. Resveratrol augments the canonical Wnt signaling pathway in promoting osteoblastic differentiation of multipotent mesenchymal cells

    International Nuclear Information System (INIS)

    Zhou, Haibin; Shang, Linshan; Li, Xi; Zhang, Xiyu; Gao, Guimin; Guo, Chenhong; Chen, Bingxi; Liu, Qiji; Gong, Yaoqin; Shao, Changshun

    2009-01-01

    Resveratrol has been shown to possess many health-benefiting effects, including the promotion of bone formation. In this report we investigated the mechanism by which resveratrol promotes osteoblastic differentiation from pluripotent mesenchymal cells. Since Wnt signaling is well documented to induce osteoblastogenesis and bone formation, we characterized the factors involved in Wnt signaling in response to resveratrol treatment. Resveratrol treatment of mesenchymal cells led to an increase in stabilization and nuclear accumulation of β-catenin dose-dependently and time-dependently. As a consequence of the increased nuclear accumulation of β-catenin, the ability to activate transcription of β-catenin-TCF/LEF target genes that are required for osteoblastic differentiation was upregulated. However, resveratrol did not affect the initial step of the Wnt signaling pathway, as resveratrol was as effective in upregulating the activity of β-catenin in cells in which Lrp5 was knocked down as in control cells. In addition, while conditioned medium enriched in Wnt signaling antagonist Dkk1 was able to inhibit Wnt3a-induced β-catenin upregulation, this inhibitory effect can be abolished in resveratrol-treated cells. Furthermore, we showed that the level of glycogen synthase kinase 3β (GSK-3β), which phosphorylates and destabilizes β-catenin, was reduced in response to resveratrol treatment. The phosphorylation of GSK-3β requires extracellular signal-regulated kinase (ERK)1/2. Together, our data indicate that resveratrol promotes osteoblastogenesis and bone formation by augmenting Wnt signaling.

  7. Factors influencing accruement of contact hours for nurses.

    Science.gov (United States)

    Kubsch, Sylvia; Henniges, Amy; Lorenzoni, Nancy; Eckardt, Sally; Oleniczak, Sandra

    2003-01-01

    A decline in attendance at continuing education (CE) in nursing activities was observed in a Midwest state where CE attendance is not required. The purpose of this research study was to identify the effect of attitude, extrinsic and intrinsic reinforcement, and deterrents on contact hour accrual. A convenience sample of 282 registered nurses was surveyed using a researcher-constructed instrument determined to be valid and reliable. Registered nurses earning 0 to 15 contact hours annually reported accruing fewer contact hours in 1999 than in an average year. Registered nurses who earned 16 to 45+ contact hours annually reported earning more contact hours in 1999 than in an average year. Intrinsic reinforcement was found to be a significant motivator (r [257] = .242; p Operant Conditioning Theory has use in explaining registered nurse attendance at CE activities. CE planners should consider placing more emphasis on intrinsic rather than extrinsic reinforcement to encourage staff to attend CE activities.

  8. [Contact allergy to henna tattoos].

    Science.gov (United States)

    Steinkjer, Bjarte; Stangeland, Katarina Zak; Mikkelsen, Carsten Sauer

    2011-03-18

    Tattoos with henna colours have become very popular and the prevalence of contact allergy seems to increase. This is a short review article based on our own clinical experience and literature identified through a search in PubMed with the words "henna", "paraphenylendiamin" and "allergic contact dermatitis." A case report is included. It is well documented that many experience skin reactions after henna tattoos. The cause is almost always contact allergy to the azo compound paraphenylendiamin, which is added to speed up the process and make the colour darker. Most people, including children, get henna tattoos during vacations in Asia or the Mediterranean. Established contact allergy is permanent. Many hair-colour products contain paraphenylendiamin, and persons with contact allergy against the product may develop a very strong contact allergic eczema by use of such substances. Acute reactions are treated with local cortisone products, or with systemic steroids. Cross reaction to substances with a similar chemical structure may occur. Tattoos with paraphenylendiamin-containing henna colours should be avoided.

  9. Differentiation within autologous fibrin scaffolds of porcine dermal cells with the mesenchymal stem cell phenotype

    International Nuclear Information System (INIS)

    Puente, Pilar de la; Ludeña, Dolores; López, Marta; Ramos, Jennifer; Iglesias, Javier

    2013-01-01

    Porcine mesenchymal stem cells (pMSCs) are an attractive source of cells for tissue engineering because their properties are similar to those of human stem cells. pMSCs can be found in different tissues but their dermal origin has not been studied in depth. Additionally, MSCs differentiation in monolayer cultures requires subcultured cells, and these cells are at risk of dedifferentiation when implanting them into living tissue. Following this, we attempted to characterize the MSCs phenotype of porcine dermal cells and to evaluate their cellular proliferation and differentiation in autologous fibrin scaffolds (AFSs). Dermal biopsies and blood samples were obtained from 12 pigs. Dermal cells were characterized by flow cytometry. Frozen autologous plasma was used to prepare AFSs. pMSC differentiation was studied in standard structures (monolayers and pellets) and in AFSs. The pMSCs expressed the CD90 and CD29 markers of the mesenchymal lineage. AFSs afforded adipogenic, osteogenic and chondrogenic differentiation. The porcine dermis can be proposed to be a good source of MSCs with adequate proliferative capacity and a suitable expression of markers. The pMSCs also showed optimal proliferation and differentiation in AFSs, such that these might serve as a promising autologous and implantable material for use in tissue engineering. -- Highlights: ► Low fibrinogen concentration provides a suitable matrix for cell migration and differentiation. ► Autologous fibrin scaffolds is a promising technique in tissue engineering. ► Dermal cells are an easily accessible mesenchymal stem cell source. ► Fibrin scaffolds afforded adipogenic, osteogenic and chondrogenic differentiation.

  10. Recurrent malignant variant of phosphaturic mesenchymal tumor with oncogenic osteomalacia

    International Nuclear Information System (INIS)

    Ogose, A.; Hotta, Tetsuo; Hatano, Hiroshi; Endo, Naoto; Emura, Iwao; Umezu, Hajime; Inoue, Yoshiya

    2001-01-01

    Phosphaturic mesenchymal tumor is a rare neoplasm which causes osteomalacia or rickets. The tumor typically follows a benign clinical course. Even in the rare malignant cases, local recurrence and distant metastasis are uncommon. We report on an example of a malignant phosphaturic mesenchymal tumor which recurred several times over 16 years concurrently causing hypophosphatemia, bone pain, and osteomalacia. Following each surgery, symptoms and hypophosphatemia improved. The patient died of disease 17 years after the first surgery. Histologically, the initial tumor was composed of small spindle cells with clusters of giant cells, prominent blood vessels, poorly formed cartilaginous areas, and crystalline material. Cytological atypia was minimal. Following multiple recurrences, the tumor demonstrated areas of high-grade sarcoma exhibiting marked pleomorphism, numerous mitotic figures, and p53 overexpression. This case illustrates the potential lethality of incompletely removed phosphaturic mesenchymal tumors. (orig.)

  11. Recurrent malignant variant of phosphaturic mesenchymal tumor with oncogenic osteomalacia

    Energy Technology Data Exchange (ETDEWEB)

    Ogose, A.; Hotta, Tetsuo; Hatano, Hiroshi; Endo, Naoto [Dept. of Orthopedic Surgery, Niigata University School of Medicine, Asahimachi, Niigata (Japan); Emura, Iwao; Umezu, Hajime [Dept. of Pathology, Niigata University School of Medicine, Niigata (Japan); Inoue, Yoshiya [Dept. of Orthopedic Surgery, Seirei Hamamatsu General Hospital, Hamamatsu (Japan)

    2001-02-01

    Phosphaturic mesenchymal tumor is a rare neoplasm which causes osteomalacia or rickets. The tumor typically follows a benign clinical course. Even in the rare malignant cases, local recurrence and distant metastasis are uncommon. We report on an example of a malignant phosphaturic mesenchymal tumor which recurred several times over 16 years concurrently causing hypophosphatemia, bone pain, and osteomalacia. Following each surgery, symptoms and hypophosphatemia improved. The patient died of disease 17 years after the first surgery. Histologically, the initial tumor was composed of small spindle cells with clusters of giant cells, prominent blood vessels, poorly formed cartilaginous areas, and crystalline material. Cytological atypia was minimal. Following multiple recurrences, the tumor demonstrated areas of high-grade sarcoma exhibiting marked pleomorphism, numerous mitotic figures, and p53 overexpression. This case illustrates the potential lethality of incompletely removed phosphaturic mesenchymal tumors. (orig.)

  12. Primary extraskeletal mesenchymal chondrosarcoma arising from the iliac vein

    Directory of Open Access Journals (Sweden)

    Hua Zhang

    2017-10-01

    Full Text Available The iliac vein is an extremely rare site for mesenchymal chondrosarcoma, and patients with primary extraskeletal mesenchymal chondrosarcoma arising from a vein always suffer a very poor prognosis. We report a case of a 45-year-old female who presented with a 5-month history of left leg edema in 2015. Contrast-enhanced computed tomography showed a large mass in the left iliac vein with scattered calcifications. Wide-margin resection was performed, and histopathologic and immunohistochemical analyses confirmed the presence of intraluminal mesenchymal chondrosarcoma with local invasion out of the vein wall. Due to poor patient compliance, postoperative neoadjuvant chemotherapy and radiotherapy were not started, and a bone scan performed 16 weeks postoperatively showed multiple bone metastases. The patient died on the twenty-fourth postoperative week.

  13. Mesenchymal Stem Cells and the Origin of Ewing's Sarcoma

    Directory of Open Access Journals (Sweden)

    Patrick P. Lin

    2011-01-01

    Full Text Available The origin of Ewing's sarcoma is a subject of much debate. Once thought to be derived from primitive neuroectodermal cells, many now believe it to arise from a mesenchymal stem cell (MSC. Expression of the EWS-FLI1 fusion gene in MSCs changes cell morphology to resemble Ewing's sarcoma and induces expression of neuroectodermal markers. In murine cells, transformation to sarcomas can occur. In knockdown experiments, Ewing's sarcoma cells develop characteristics of MSCs and the ability to differentiate into mesodermal lineages. However, it cannot be concluded that MSCs are the cell of origin. The concept of an MSC still needs to be rigorously defined, and there may be different subpopulations of mesenchymal pluripotential cells. Furthermore, EWS-FLI1 by itself does not transform human cells, and cooperating mutations appear to be necessary. Therefore, while it is possible that Ewing's sarcoma may originate from a primitive mesenchymal cell, the idea needs to be refined further.

  14. Mesenchymal Stem Cells and the Origin of Ewing's Sarcoma

    Science.gov (United States)

    Lin, Patrick P.; Wang, Yongxing; Lozano, Guillermina

    2011-01-01

    The origin of Ewing's sarcoma is a subject of much debate. Once thought to be derived from primitive neuroectodermal cells, many now believe it to arise from a mesenchymal stem cell (MSC). Expression of the EWS-FLI1 fusion gene in MSCs changes cell morphology to resemble Ewing's sarcoma and induces expression of neuroectodermal markers. In murine cells, transformation to sarcomas can occur. In knockdown experiments, Ewing's sarcoma cells develop characteristics of MSCs and the ability to differentiate into mesodermal lineages. However, it cannot be concluded that MSCs are the cell of origin. The concept of an MSC still needs to be rigorously defined, and there may be different subpopulations of mesenchymal pluripotential cells. Furthermore, EWS-FLI1 by itself does not transform human cells, and cooperating mutations appear to be necessary. Therefore, while it is possible that Ewing's sarcoma may originate from a primitive mesenchymal cell, the idea needs to be refined further. PMID:20953407

  15. Contact isotopic- and contact ion-exchange between two adsorbents

    International Nuclear Information System (INIS)

    Bunzl, K.; Mohan, R.; Haimerl, M.

    1975-01-01

    The kinetics of contact ion exchange processes between an ion exchange membrane and resin ion exchange beads, stirred in pure water, was investigated. A general criterion was derived, which indicates whether diffusion of the ions between the intermingling electric double layers or the collision frequency between the two adsorbents is the rate dermining step. Since the latter process proved to be rate controlling under our experimental conditions, the corresponding rate equations were derived under various initial and boundary conditions. Experimentally, the kinetics of contact isotopic exchange of Cs + - and Na + -ions as well as of the reverse contact ion exchange process of Cs + -versus Na + -ions were investigated by using Na 22 and Cs 137 radioisotopes. The experiments reveal in quantitative accord with the theory that the rate of collision controlled contact ion exchange processes depends mainly on the 'exchange coefficient', the separation factor and the collision frequency. While the latter two quantities were determined independently by separate experiments, the 'exchange coefficient' was evaluated from a contact isotopic exchange experiment. (orig.) [de

  16. Effects of dexamethasone on palate mesenchymal cell phospholipase activity

    International Nuclear Information System (INIS)

    Bulleit, R.F.; Zimmerman, E.F.

    1984-01-01

    Corticosteroids will induce cleft palate in mice. One suggested mechanism for this effect is through inhibition of phospholipase activity. This hypothesis was tested by measuring the effects of dexamethasone, a synthetic corticosteroid, on phospholipase activity in cultures of palate mesenchymal cells. Palate mesenchymal cells were prelabeled with [3H]arachidonic acid. The cells were subsequently treated with various concentrations of dexamethasone. Concurrently, cultures of M-MSV-transformed 3T3 cells were prepared identically. After treatment, phospholipase activity was stimulated by the addition of serum or epidermal growth factor (EGF), and radioactivity released into the medium was taken as a measure of phospholipase activity. Dexamethasone (1 X 10(-5) or 1 X 10(-4) M) could inhibit serum-stimulated phospholipase activity in transformed 3T3 cells after 1 to 24 hr of treatment. However, no inhibition of activity was measured in palate mesenchymal cells following this period of treatment. Not until 120 hr of treatment with dexamethasone (1 X 10(-4) M) was any significant inhibition of serum-stimulated phospholipase activity observed in palate mesenchymal cells. When EGF was used to stimulate phospholipase activity, dexamethasone (1 X 10(-5) M) caused an increase in phospholipase activity in palate mesenchymal cells. These observations suggested that phospholipase in transformed 3T3 cells was sensitive to inhibition by dexamethasone. However, palate mesenchymal cell phospholipase is only minimally sensitive to dexamethasone, and in certain instances can be enhanced. These results cannot support the hypothesis that corticosteroids mediate their teratogenic effect via inhibition of phospholipase activity

  17. Solar cell with back side contacts

    Science.gov (United States)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

    2013-12-24

    A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

  18. Measuring The Contact Resistances Of Photovoltaic Cells

    Science.gov (United States)

    Burger, D. R.

    1985-01-01

    Simple method devised to measure contact resistances of photovoltaic solar cells. Method uses readily available equipment and applicable at any time during life of cell. Enables evaluation of cell contact resistance, contact-end resistance, contact resistivity, sheet resistivity, and sheet resistivity under contact.

  19. EAACI Position Paper for practical patch testing in Allergic Contact Dermatitis in children

    DEFF Research Database (Denmark)

    de Waard-van der Spek, Flora B; Darsow, Ulf; Mortz, Charlotte G

    2015-01-01

    Allergic Contact Dermatitis (ACD) in children appears to be on the increase, and contact sensitization may already begin in infancy. The diagnosis of contact dermatitis requires a careful evaluation of a patient's clinical history, physical examination and skin testing. Patch testing is the gold...

  20. Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Contribute to Chondrogenesis in Coculture with Chondrocytes.

    Science.gov (United States)

    Li, Xingfu; Duan, Li; Liang, Yujie; Zhu, Weimin; Xiong, Jianyi; Wang, Daping

    2016-01-01

    Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) have been shown as the most potential stem cell source for articular cartilage repair. In this study, we aimed to develop a method for long-term coculture of human articular chondrocytes (hACs) and hUCB-MSCs at low density in vitro to determine if the low density of hACs could enhance the hUCB-MSC chondrogenic differentiation as well as to determine the optimal ratio of the two cell types. Also, we compared the difference between direct coculture and indirect coculture at low density. Monolayer cultures of hUCB-MSCs and hACs were investigated at different ratios, at direct cell-cell contact groups for 21 days. Compared to direct coculture, hUCB-MSCs and hACs indirect contact culture significantly increased type II collagen (COL2) and decreased type I collagen (COL1) protein expression levels. SRY-box 9 (SOX9) mRNA levels and protein expression were highest in indirect coculture. Overall, these results indicate that low density direct coculture induces fibrocartilage. However, indirect coculture in conditioned chondrocyte cell culture medium can increase expression of chondrogenic markers and induce hUCB-MSCs differentiation into mature chondrocytes. This work demonstrates that it is possible to promote chondrogenesis of hUCB-MSCs in combination with hACs, further supporting the concept of novel coculture strategies for tissue engineering.

  1. Mesenchymal Stem Cells Modulate Differentiation of Myeloid Progenitor Cells During Inflammation.

    Science.gov (United States)

    Amouzegar, Afsaneh; Mittal, Sharad K; Sahu, Anuradha; Sahu, Srikant K; Chauhan, Sunil K

    2017-06-01

    Mesenchymal stem cells (MSCs) possess distinct immunomodulatory properties and have tremendous potential for use in therapeutic applications in various inflammatory diseases. MSCs have been shown to regulate pathogenic functions of mature myeloid inflammatory cells, such as macrophages and neutrophils. Intriguingly, the capacity of MSCs to modulate differentiation of myeloid progenitors (MPs) to mature inflammatory cells remains unknown to date. Here, we report the novel finding that MSCs inhibit the expression of differentiation markers on MPs under inflammatory conditions. We demonstrate that the inhibitory effect of MSCs is dependent on direct cell-cell contact and that this intercellular contact is mediated through interaction of CD200 expressed by MSCs and CD200R1 expressed by MPs. Furthermore, using an injury model of sterile inflammation, we show that MSCs promote MP frequencies and suppress infiltration of inflammatory cells in the inflamed tissue. We also find that downregulation of CD200 in MSCs correlates with abrogation of their immunoregulatory function. Collectively, our study provides unequivocal evidence that MSCs inhibit differentiation of MPs in the inflammatory environment via CD200-CD200R1 interaction. Stem Cells 2017;35:1532-1541. © 2017 AlphaMed Press.

  2. Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Contribute to Chondrogenesis in Coculture with Chondrocytes

    Directory of Open Access Journals (Sweden)

    Xingfu Li

    2016-01-01

    Full Text Available Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs have been shown as the most potential stem cell source for articular cartilage repair. In this study, we aimed to develop a method for long-term coculture of human articular chondrocytes (hACs and hUCB-MSCs at low density in vitro to determine if the low density of hACs could enhance the hUCB-MSC chondrogenic differentiation as well as to determine the optimal ratio of the two cell types. Also, we compared the difference between direct coculture and indirect coculture at low density. Monolayer cultures of hUCB-MSCs and hACs were investigated at different ratios, at direct cell-cell contact groups for 21 days. Compared to direct coculture, hUCB-MSCs and hACs indirect contact culture significantly increased type II collagen (COL2 and decreased type I collagen (COL1 protein expression levels. SRY-box 9 (SOX9 mRNA levels and protein expression were highest in indirect coculture. Overall, these results indicate that low density direct coculture induces fibrocartilage. However, indirect coculture in conditioned chondrocyte cell culture medium can increase expression of chondrogenic markers and induce hUCB-MSCs differentiation into mature chondrocytes. This work demonstrates that it is possible to promote chondrogenesis of hUCB-MSCs in combination with hACs, further supporting the concept of novel coculture strategies for tissue engineering.

  3. Multiscale grooved titanium processed with femtosecond laser influences mesenchymal stem cell morphology, adhesion, and matrix organization.

    Science.gov (United States)

    Dumas, Virginie; Rattner, Aline; Vico, Laurence; Audouard, Eric; Dumas, Jean Claude; Naisson, Pierre; Bertrand, Philippe

    2012-11-01

    The femtosecond laser processing enabled the structuring of six types of surfaces on titanium-6aluminium-4vanadium (Ti-6Al-4V) plates. The obtained hierarchical features consisted of a combination of microgrooves and oriented nanostructures. By adjusting beam properties such as laser polarization, the width of the microgrooves (20 or 60 μm) and the orientation of the nanostructures (parallel or perpendicular to the microgrooves) can be precisely controlled. Mesenchymal stem cells (MSCs) grown on these structured surfaces produced cytoplasmic extensions with focal contacts, while on the smooth titanium, the cells were found to be well spread and without any focal contact 12 h postseeding. The 600-nm wide nanostructures on their own were sufficient to orient the MSCs. For the multiscale structured areas, when the orientation of the nanostructures was orthogonal in relation to the microgrooves, there was an important decrease in or even a loss of cell alignment signifying that cells were sensitive to the directional nanostructures in the microgrooves. At 7 days, cell proliferation was not affected but the direction of nanostructures controlled the matrix organization. The ultrafast laser, as a new method for producing micro-nanohybrid surfaces, is a promising approach to promote desired tissue organization for tissue engineering. Copyright © 2012 Wiley Periodicals, Inc.

  4. Mesenchymal stem cells cancel azoxymethane-induced tumor initiation.

    Science.gov (United States)

    Nasuno, Masanao; Arimura, Yoshiaki; Nagaishi, Kanna; Isshiki, Hiroyuki; Onodera, Kei; Nakagaki, Suguru; Watanabe, Shuhei; Idogawa, Masashi; Yamashita, Kentaro; Naishiro, Yasuyoshi; Adachi, Yasushi; Suzuki, Hiromu; Fujimiya, Mineko; Imai, Kohzoh; Shinomura, Yasuhisa

    2014-04-01

    The role of mesenchymal stem cells (MSCs) in tumorigenesis remains controversial. Therefore, our goal was to determine whether exogenous MSCs possess intrinsic antineoplastic or proneoplastic properties in azoxymethane (AOM)-induced carcinogenesis. Three in vivo models were studied: an AOM/dextran sulfate sodium colitis-associated carcinoma model, an aberrant crypt foci model, and a model to assess the acute apoptotic response of a genotoxic carcinogen (AARGC). We also performed in vitro coculture experiments. As a result, we found that MSCs partially canceled AOM-induced tumor initiation but not tumor promotion. Moreover, MSCs inhibited the AARGC in colonic epithelial cells because of the removal of O(6)-methylguanine (O(6) MeG) adducts through O(6) MeG-DNA methyltransferase activation. Furthermore, MSCs broadly affected the cell-cycle machinery, potentially leading to G1 arrest in vivo. Coculture of IEC-6 rat intestinal cells with MSCs not only arrested the cell cycle at the G1 phase, but also induced apoptosis. The anti-carcinogenetic properties of MSCs in vitro required transforming growth factor (TGF)-β signaling because such properties were completely abrogated by absorption of TGF-β under indirect coculture conditions. MSCs inhibited AOM-induced tumor initiation by preventing the initiating cells from sustaining DNA insults and subsequently inducing G1 arrest in the initiated cells that escaped from the AARGC. Furthermore, tumor initiation perturbed by MSCs might potentially dysregulate WNT and TGF-β-Smad signaling pathways in subsequent tumorigenesis. Obtaining a better understanding of MSC functions in colon carcinogenesis is essential before commencing the broader clinical application of promising MSC-based therapies for cancer-prone patients with inflammatory bowel disease. © AlphaMed Press.

  5. Beyond the GIST: Mesenchymal Tumors of the Stomach

    Science.gov (United States)

    Menias, Christine O.; Gaballah, Ayman H.; Shroff, Stuti; Taggart, Melissa W.; Garg, Naveen; Elsayes, Khaled M.

    2013-01-01

    Intramural gastric masses arise in the wall of the stomach (generally within the submucosa or muscularis propria), often with intact overlying mucosa. These tumors are typically mesenchymal in origin and have overlapping radiologic appearances. A combination of features such as location, attenuation, enhancement, and growth pattern may suggest one diagnosis over another. Gastrointestinal stromal tumors (GISTs) account for the majority of intramural tumors and can vary widely in appearance, from small intraluminal lesions to exophytic masses that protrude into the peritoneal cavity, commonly with areas of hemorrhage or necrosis. A well-circumscribed mass measuring −70 to −120 HU is a lipoma. Leiomyomas usually manifest as low-attenuation masses at the gastric cardia. Homogeneous attenuation is a noteworthy characteristic of schwannomas, particularly for larger lesions that might otherwise be mistaken for GISTs. A hypervascular mass in the antrum is a common manifestation of glomus tumors. Hemangiomas are also hypervascular but often manifest in childhood. Inflammatory fibroid polyps usually arise as a polypoid mass in the antrum. Inflammatory myofibroblastic tumors are infiltrative neoplasms with a propensity for local recurrence. Plexiform fibromyxomas are rare, usually antral tumors. Carcinoid tumors are epithelial in origin, but often submucosal in location, and therefore should be distinguished from other intramural lesions. Multiple carcinoid tumors are associated with hypergastrinemia, either in the setting of chronic atrophic gastritis or Zollinger-Ellison syndrome. Sporadic solitary carcinoid tumors not associated with hypergastrinemia have a higher rate of metastasis. Histopathologic analysis, including immunohistochemistry, is usually required for diagnosis of intramural masses. © RSNA, 2013 PMID:24108557

  6. Autologous Mesenchymal Stem Cell and Islet Cotransplantation: Safety and Efficacy.

    Science.gov (United States)

    Wang, Hongjun; Strange, Charlie; Nietert, Paul J; Wang, Jingjing; Turnbull, Taylor L; Cloud, Colleen; Owczarski, Stefanie; Shuford, Betsy; Duke, Tara; Gilkeson, Gary; Luttrell, Louis; Hermayer, Kathie; Fernandes, Jyotika; Adams, David B; Morgan, Katherine A

    2018-01-01

    Islet engraftment after transplantation is impaired by high rates of islet/β cell death caused by cellular stressors and poor graft vascularization. We studied whether cotransplantation of ex vivo expanded autologous bone marrow-derived mesenchymal stem cells (MSCs) with islets is safe and beneficial in chronic pancreatitis patients undergoing total pancreatectomy with islet autotransplantation. MSCs were harvested from the bone marrow of three islet autotransplantation patients and expanded at our current Good Manufacturing Practices (cGMP) facility. On the day of islet transplantation, an average dose of 20.0 ± 2.6 ×10 6 MSCs was infused with islets via the portal vein. Adverse events and glycemic control at baseline, 6, and 12 months after transplantation were compared with data from 101 historical control patients. No adverse events directly related to the MSC infusions were observed. MSC patients required lower amounts of insulin during the peritransplantation period (p = .02 vs. controls) and had lower 12-month fasting blood glucose levels (p = .02 vs. controls), smaller C-peptide declines over 6 months (p = .01 vs. controls), and better quality of life compared with controls. In conclusion, our pilot study demonstrates that autologous MSC and islet cotransplantation may be a safe and potential strategy to improve islet engraftment after transplantation. (Clinicaltrials.gov registration number: NCT02384018). Stem Cells Translational Medicine 2018;7:11-19. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  7. Mesenchymal Stem Cells Enhance Allogeneic Islet Engraftment in Nonhuman Primates

    Science.gov (United States)

    Berman, Dora M.; Willman, Melissa A.; Han, Dongmei; Kleiner, Gary; Kenyon, Norman M.; Cabrera, Over; Karl, Julie A.; Wiseman, Roger W.; O'Connor, David H.; Bartholomew, Amelia M.; Kenyon, Norma S.

    2010-01-01

    OBJECTIVE To test the graft-promoting effects of mesenchymal stem cells (MSCs) in a cynomolgus monkey model of islet/bone marrow transplantation. RESEARCH DESIGN AND METHODS Cynomolgus MSCs were obtained from iliac crest aspirate and characterized through passage 11 for phenotype, gene expression, differentiation potential, and karyotype. Allogeneic donor MSCs were cotransplanted intraportally with islets on postoperative day (POD) 0 and intravenously with donor marrow on PODs 5 and 11. Recipients were followed for stabilization of blood glucose levels, reduction of exogenous insulin requirement (EIR), C-peptide levels, changes in peripheral blood T regulatory cells, and chimerism. Destabilization of glycemia and increases in EIR were used as signs of rejection; additional intravenous MSCs were administered to test the effect on reversal of rejection. RESULTS MSC phenotype and a normal karyotype were observed through passage 11. IL-6, IL-10, vascular endothelial growth factor, TGF-β, hepatocyte growth factor, and galectin-1 gene expression levels varied among donors. MSC treatment significantly enhanced islet engraftment and function at 1 month posttransplant (n = 8), as compared with animals that received islets without MSCs (n = 3). Additional infusions of donor or third-party MSCs resulted in reversal of rejection episodes and prolongation of islet function in two animals. Stable islet allograft function was associated with increased numbers of regulatory T-cells in peripheral blood. CONCLUSIONS MSCs may provide an important approach for enhancement of islet engraftment, thereby decreasing the numbers of islets needed to achieve insulin independence. Furthermore, MSCs may serve as a new, safe, and effective antirejection therapy. PMID:20622174

  8. Nanoscale Mechanical Stimulation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    H Nikukar

    2014-05-01

    We observed significant responses after 1 and 2-week stimulations in cell number, cell shapes and phenotypical markers. Microarray was performed for all groups. Cell count showed normal cell growth with stimulation. However, cell surface area, cell perimeter, and arboration after 1-week stimulation showed significant increases. Immunofluorescent studies have showed significant increase in osteocalcin production after stimulation. Conclusions: Nanoscale mechanical vibration showed significant changes in human mesenchymal stem cell behaviours. Cell morphology changed to become more polygonal and increased expression of the osteoblast markers were noted. These findings with gene regulation changes suggesting nanoscale mechanostimulation has stimulated osteoblastogenesis.  Keywords:  Mesenchymal, Nanoscale, Stem Cells.

  9. Primary intradural mesenchymal chondrosarcoma of the spine in a child

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yu-Hua [Shanghai Jiao Tong University, Department of Radiology, Xin Hua Hospital, School of Medicine, Shanghai (China); Yao, Xiao-Hong [Shanghai Jiao Tong University, Department of Pathology, Xin Hua Hospital, School of Medicine, Shanghai (China)

    2007-11-15

    We report a primary intradural mesenchymal chondrosarcoma of the spine in a 3-year-old girl. MRI revealed a markedly enhancing oval mass associated with focal areas of low signal intensity extending from T11 to L1. The lesion was located posterolateral to the right side of the spinal cord, pushing the conus medullaris and cauda equina anteriorly and to the left. The adjacent spinal cord also showed serpiginous areas of flow void. The mass was completely removed. Microscopic examination and immunohistochemical studies confirmed the diagnosis of mesenchymal chondrosarcoma. The patient was free of symptoms after surgery. (orig.)

  10. Primary intradural mesenchymal chondrosarcoma of the spine in a child

    International Nuclear Information System (INIS)

    Li, Yu-Hua; Yao, Xiao-Hong

    2007-01-01

    We report a primary intradural mesenchymal chondrosarcoma of the spine in a 3-year-old girl. MRI revealed a markedly enhancing oval mass associated with focal areas of low signal intensity extending from T11 to L1. The lesion was located posterolateral to the right side of the spinal cord, pushing the conus medullaris and cauda equina anteriorly and to the left. The adjacent spinal cord also showed serpiginous areas of flow void. The mass was completely removed. Microscopic examination and immunohistochemical studies confirmed the diagnosis of mesenchymal chondrosarcoma. The patient was free of symptoms after surgery. (orig.)

  11. Mesenchymal Stem Cells Improve Healing of Diabetic Foot Ulcer

    Directory of Open Access Journals (Sweden)

    Yue Cao

    2017-01-01

    Full Text Available Mesenchymal stem cells (MSCs, an ideal cell source for regenerative therapy with no ethical issues, play an important role in diabetic foot ulcer (DFU. Growing evidence has demonstrated that MSCs transplantation can accelerate wound closure, ameliorate clinical parameters, and avoid amputation. In this review, we clarify the mechanism of preclinical studies, as well as safety and efficacy of clinical trials in the treatment of DFU. Bone marrow-derived mesenchymal stem cells (BM-MSCs, compared with MSCs derived from other tissues, may be a suitable cell type that can provide easy, effective, and cost-efficient transplantation to treat DFU and protect patients from amputation.

  12. Epithelial-to-Mesenchymal Transition in Pancreatic Adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Carla Cano

    2010-01-01

    Full Text Available Epithelial to mesenchymal transition (EMT is a physiologic process that allows morphological and genetic changes of carcinoma cells from an epithelial to a mesenchymal phenotype, which is the basis of the high metastatic potential of pancreatic cancer cells. EMT is triggered by various tumor microenvironmental factors, including cytokines, growth factors, and chemotherapeutic agents. This review summarizes the state-of-the-art knowledge on the molecular mechanisms that support pancreatic cancer EMT and the evidences that support its involvement in invasiveness/aggressiveness, and the drug resistance of pancreatic cancer cells.

  13. Microencapsulation of Hepatocytes and Mesenchymal Stem Cells for Therapeutic Applications.

    Science.gov (United States)

    Meier, Raphael P H; Montanari, Elisa; Morel, Philippe; Pimenta, Joël; Schuurman, Henk-Jan; Wandrey, Christine; Gerber-Lemaire, Sandrine; Mahou, Redouan; Bühler, Leo H

    2017-01-01

    Encapsulated hepatocyte transplantation and encapsulated mesenchymal stem cell transplantation are newly developed potential treatments for acute and chronic liver diseases, respectively. Cells are microencapsulated in biocompatible semipermeable alginate-based hydrogels. Microspheres protect cells against antibodies and immune cells, while allowing nutrients, small/medium size proteins and drugs to diffuse inside and outside the polymer matrix. Microencapsulated cells are assessed in vitro and designed for experimental transplantation and for future clinical applications.Here, we describe the protocol for microencapsulation of hepatocytes and mesenchymal stem cells within hybrid poly(ethylene glycol)-alginate hydrogels.

  14. Magnetism in Pd: Magnetoconductance and transport spectroscopy of atomic contacts

    Science.gov (United States)

    Strigl, F.; Keller, M.; Weber, D.; Pietsch, T.; Scheer, E.

    2016-10-01

    Since the rapid technological progress demands for ever smaller storage units, the emergence of stable magnetic order in nanomaterials down to the single-atom regime has attracted huge scientific attention to date. Electronic transport spectroscopy has been proven to be a versatile tool for the investigation of electronic, magnetic, and mechanical properties of atomic contacts. Here we report a comprehensive experimental study of the magnetoconductance and electronic properties of Pd atomic contacts at low temperature. The analysis of electronic transport (d I /d V ) spectra and the magnetoconductance curves yields a diverse behavior of Pd single-atom contacts, which is attributed to different contact configurations. The magnetoconductance shows a nonmonotonous but mostly continuous behavior, comparable to those found in atomic contacts of band ferromagnets. In the d I /d V spectra, frequently, a pronounced zero-bias anomaly (ZBA) as well as an aperiodic and nonsymmetric fluctuation pattern are observed. While the ZBA can be interpreted as a sign of the Kondo effect, suggesting the presence of magnetic impurity, the fluctuations are evaluated in the framework of conductance fluctuations in relation to the magnetoconductance traces and to previous findings in Au atomic contacts. This thorough analysis reveals that the magnetoconductance and transport spectrum of Au atomic contacts can completely be accounted for by conductance fluctuations, while in Pd contacts the presence of local magnetic order is required.

  15. [Mesenchymal stroma cells and their niche].

    Science.gov (United States)

    Schneider, R K

    2013-11-01

    Stem cells reside in a highly specialized, complex microenvironment that is known as the stem cell niche. The stem cell niche can be described as an anatomically defined space where the stem cell is localized and nourished and stem cell quiescence, proliferation and differentiation are maintained. Tissue engineering aims to imitate the stem cell niche to (I) induce a directed differentiation, (II) maintain the self-renewal capacity or (III) find a regulated balance between self-renewal and differentiation. Mesenchymal stem or stromal cells (MSC) can differentiate in three-dimensional collagen gels into functional osteoblasts when subjected to a phosphate-rich cultivation medium. Furthermore, they acquire a prosynthetic, matrix remodeling, contractile phenotype. Medial artery calcification in patients with chronic kidney disease also proceeds through intramembranous ossification resulting from osteoblast-induced calcification of the collagen extracellular matrix. Thus, the influence of uremic cultivation conditions as a pathophysiological stimulus on MSC and endothelial cells was analyzed with special regards to matrix remodeling, vascularization and calcification. The results showed that BMP-2/4 mediated MSC (mal)differentiation into osteoblasts with acquired matrix remodeling phenotype and loss of proangiogenic capacity. These studies have led to the conclusion that uremia has detrimental effects on the stem cell niche and promotes the continuous calcification by osteogenic (mal)differentiation. In summary, recent studies have shown the conducting and regulating effect of the stem cell niche under physiological conditions that can be applied and mimicked for tissue engineering applications. However, under pathological conditions the stem cell niche can have detrimental effects on stem cell function and can promote disease progression.

  16. Measurement of Critical Contact Angle in a Microgravity Space Experiment

    Science.gov (United States)

    Concus, P.; Finn, R.; Weislogel, M.

    1998-01-01

    Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the Interface Configuration Experiment on board the USMT,2 Space Shuttle flight. The experiment's "double proboscis" containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium.

  17. Influence of Thermal Effects During Blade-Casing Contact Experiments

    OpenAIRE

    Millecamps , Antoine; Brunel , Jean-François; Dufrenoy , Philippe; Garcin , François; Nucci , Marco

    2009-01-01

    International audience; In rotating machinery, notably in modern high efficiency compressors, a critical requirement for optimal performance consists in minimizing radial clearances between the rotating bladed disk and the casing. This solution significantly increases the risks of contact between rotating bladed disk and casing and may lead in specific conditions to catastrophic behavior (component failure, etc.). The physical phenomena and mechanisms involved in blade-casing contact interact...

  18. Elevated-temperature (6000F), manual contact ultrasonic examination

    International Nuclear Information System (INIS)

    Donnelly, C.W.

    1981-01-01

    Manual contact ultrasonic examination at temperatures above 250 0 F has not been successful in providing meaningful results. Sensitivity of standard transducers degrades rapidly at 250 0 F and above. It has been demonstrated that by using standard transducers and commercially available wedges and couplants in combination with a couplant/cooler system, manual contact ultrasonic examination can be performed at 600 0 F for an essentially 100% duty cycle in conformance to the sensitivity requirement of the ASME B and PV Code

  19. Microneedle physical contact as a therapeutic for abnormal scars

    OpenAIRE

    Yeo, David C.; Balmayor, Elizabeth R.; Schantz, Jan-Thorsten; Xu, Chenjie

    2017-01-01

    Background Abnormal (keloid and hypertrophic) scars are a significant affliction with no satisfactory single modality therapy to-date. Available options are often ineffective, painful, potentially hazardous, and require healthcare personnel involvement. Herein a self-administered microneedle device based on drug-free physical contact for inhibiting abnormal scars is reported. Its therapeutic activity through microneedle contact eliminates hazards associated with toxic anti-scarring drugs whil...

  20. Contact Resistance of Ceramic Interfaces Between Materials Used for Solid Oxide Fuel Cell Applications

    DEFF Research Database (Denmark)

    Koch, Søren

    The contact resistance can be divided into two main contributions. The small area of contact between ceramic components results in resistance due to current constriction. Resistive phases or potential barriers at the interface result in an interface contribution to the contact resistance, which may....... The influence of the mechanical load on the contact resistance was ascribed to an area effect. The contact resistance of the investigated materials was dominated by current constric-tion at high temperatures. The measured contact resistance was comparable to the resis-tance calculated on basis of the contact...... areas found by optical and electron microscopy. At low temperatures, the interface contribution to the contact resistance was dominating. The cobaltite interface could be described by one potential barrier at the contact interface, whereas the manganite interfaces required several consecutive potential...

  1. Enhanced epithelial to mesenchymal transition (EMT) and upregulated MYC in ectopic lesions contribute independently to endometriosis.

    Science.gov (United States)

    Proestling, Katharina; Birner, Peter; Gamperl, Susanne; Nirtl, Nadine; Marton, Erika; Yerlikaya, Gülen; Wenzl, Rene; Streubel, Berthold; Husslein, Heinrich

    2015-07-22

    Epithelial to mesenchymal transition (EMT) is a process in which epithelial cells lose polarity and cell-to-cell contacts and acquire the migratory and invasive abilities of mesenchymal cells. These abilities are thought to be prerequisites for the establishment of endometriotic lesions. A hallmark of EMT is the functional loss of E-cadherin (CDH1) expression in epithelial cells. TWIST1, a transcription factor that represses E-cadherin transcription, is among the EMT inducers. SNAIL, a zinc-finger transcription factor, and its close relative SLUG have similar properties to TWIST1 and are thus also EMT inducers. MYC, which is upregulated by estrogens in the uterus by an estrogen response cis-acting element (ERE) in its promoter, is associated with proliferation in endometriosis. The role of EMT and proliferation in the pathogenesis of endometriosis was evaluated by analyzing TWIST1, CDH1 and MYC expression. CDH1, TWIST1, SNAIL and SLUG mRNA expression was analyzed by qRT-PCR from 47 controls and 74 patients with endometriosis. Approximately 42 ectopic and 62 eutopic endometrial tissues, of which 30 were matched samples, were collected during the same surgical procedure. We evaluated TWIST1 and MYC protein expression by immunohistochemistry (IHC) in the epithelial and stromal tissue of 69 eutopic and 90 ectopic endometrium samples, of which 49 matched samples were analyzed from the same patient. Concordant expression of TWIST1/SNAIL/SLUG and CDH1 but also of TWIST1 and MYC was analyzed. We found that TWIST1, SNAIL and SLUG are overexpressed (p < 0.001, p = 0.016 and p < 0.001) in endometriosis, while CDH1 expression was concordantly reduced in these samples (p < 0.001). Similar to TWIST1, the epithelial expression of MYC was also significantly enhanced in ectopic endometrium compared to eutopic tissues (p = 0.008). We found exclusive expression of either TWIST1 or MYC in the same samples (p = 0.003). Epithelial TWIST1 is overexpressed in

  2. Nestin-positive mesenchymal stem cells favour the astroglial lineage in neural progenitors and stem cells by releasing active BMP4

    Directory of Open Access Journals (Sweden)

    Leprince Pierre

    2004-09-01

    Full Text Available Abstract Background Spontaneous repair is limited after CNS injury or degeneration because neurogenesis and axonal regrowth rarely occur in the adult brain. As a result, cell transplantation has raised much interest as potential treatment for patients with CNS lesions. Several types of cells have been considered as candidates for such cell transplantation and replacement therapies. Foetal brain tissue has already been shown to have significant effects in patients with Parkinson's disease. Clinical use of the foetal brain tissue is, however, limited by ethical and technical problems as it requires high numbers of grafted foetal cells and immunosuppression. Alternatively, several reports suggested that mesenchymal stem cells, isolated from adult bone marrow, are multipotent cells and could be used in autograft approach for replacement therapies. Results In this study, we addressed the question of the possible influence of mesenchymal stem cells on neural stem cell fate. We have previously reported that adult rat mesenchymal stem cells are able to express nestin in defined culture conditions (in the absence of serum and after 25 cell population doublings and we report here that nestin-positive (but not nestin-negative mesenchymal stem cells are able to favour the astroglial lineage in neural progenitors and stem cells cultivated from embryonic striatum. The increase of the number of GFAP-positive cells is associated with a significant decrease of the number of Tuj1- and O4-positive cells. Using quantitative RT-PCR, we demonstrate that mesenchymal stem cells express LIF, CNTF, BMP2 and BMP4 mRNAs, four cytokines known to play a role in astroglial fate decision. In this model, BMP4 is responsible for the astroglial stimulation and oligodendroglial inhibition, as 1 this cytokine is present in a biologically-active form only in nestin-positive mesenchymal stem cells conditioned medium and 2 anti-BMP4 antibodies inhibit the nestin-positive mesenchymal

  3. Contact Estimation in Robot Interaction

    Directory of Open Access Journals (Sweden)

    Filippo D'Ippolito

    2014-07-01

    Full Text Available In the paper, safety issues are examined in a scenario in which a robot manipulator and a human perform the same task in the same workspace. During the task execution, the human should be able to physically interact with the robot, and in this case an estimation algorithm for both interaction forces and a contact point is proposed in order to guarantee safety conditions. The method, starting from residual joint torque estimation, allows both direct and adaptive computation of the contact point and force, based on a principle of equivalence of the contact forces. At the same time, all the unintended contacts must be avoided, and a suitable post-collision strategy is considered to move the robot away from the collision area or else to reduce impact effects. Proper experimental tests have demonstrated the applicability in practice of both the post-impact strategy and the estimation algorithms; furthermore, experiments demonstrate the different behaviour resulting from the adaptation of the contact point as opposed to direct calculation.

  4. Bioreactor-induced mesenchymal progenitor cell differentiation and elastic fiber assembly in engineered vascular tissues.

    Science.gov (United States)

    Lin, Shigang; Mequanint, Kibret

    2017-09-01

    In vitro maturation of engineered vascular tissues (EVT) requires the appropriate incorporation of smooth muscle cells (SMC) and extracellular matrix (ECM) components similar to native arteries. To this end, the aim of the current study was to fabricate 4mm inner diameter vascular tissues using mesenchymal progenitor cells seeded into tubular scaffolds. A dual-pump bioreactor operating either in perfusion or pulsatile perfusion mode was used to generate physiological-like stimuli to promote progenitor cell differentiation, extracellular elastin production, and tissue maturation. Our data demonstrated that pulsatile forces and perfusion of 3D tubular constructs from both the lumenal and ablumenal sides with culture media significantly improved tissue assembly, effectively inducing mesenchymal progenitor cell differentiation to SMCs with contemporaneous elastin production. With bioreactor cultivation, progenitor cells differentiated toward smooth muscle lineage characterized by the expression of smooth muscle (SM)-specific markers smooth muscle alpha actin (SM-α-actin) and smooth muscle myosin heavy chain (SM-MHC). More importantly, pulsatile perfusion bioreactor cultivation enhanced the synthesis of tropoelastin and its extracellular cross-linking into elastic fiber compared with static culture controls. Taken together, the current study demonstrated progenitor cell differentiation and vascular tissue assembly, and provides insights into elastin synthesis and assembly to fibers. Incorporation of elastin into engineered vascular tissues represents a critical design goal for both mechanical and biological functions. In the present study, we seeded porous tubular scaffolds with multipotent mesenchymal progenitor cells and cultured in dual-pump pulsatile perfusion bioreactor. Physiological-like stimuli generated by bioreactor not only induced mesenchymal progenitor cell differentiation to vascular smooth muscle lineage but also actively promoted elastin synthesis and

  5. Isolation and cellular properties of mesenchymal cells derived from the decidua of human term placenta.

    Science.gov (United States)

    Kanematsu, Daisuke; Shofuda, Tomoko; Yamamoto, Atsuyo; Ban, Chiaki; Ueda, Takafumi; Yamasaki, Mami; Kanemura, Yonehiro

    2011-09-01

    The clinical promise of cell-based therapies is generally recognized, and has driven an intense search for good cell sources. In this study, we isolated plastic-adherent cells from human term decidua vera, called decidua-derived-mesenchymal cells (DMCs), and compared their properties with those of bone marrow-derived-mesenchymal stem cells (BM-MSCs). The DMCs strongly expressed the mesenchymal cell marker vimentin, but not cytokeratin 19 or HLA-G, and had a high proliferative potential. That is, they exhibited a typical fibroblast-like morphology for over 30 population doublings. Cells phenotypically identical to the DMCs were identified in the decidua vera, and genotyping confirmed that the DMCs were derived from the maternal components of the fetal adnexa. Flow cytometry analysis showed that the expression pattern of CD antigens on the DMCs was almost identical to that on BM-MSCs, but some DMCs expressed the CD45 antigen, and over 50% of them also expressed anti-fibroblast antigen. In vitro, the DMCs showed good differentiation into chondrocytes and moderate differentiation into adipocytes, but scant evidence of osteogenesis, compared with the BM-MSCs. Gene expression analysis showed that, compared with BM-MSCs, the DMCs expressed higher levels of TWIST2 and RUNX2 (which are associated with early mesenchymal development and/or proliferative capacity), several matrix metalloproteinases (MMP1, 3, 10, and 12), and cytokines (BMP2 and TGFB2), and lower levels of MSX2, interleukin 26, and HGF. Although DMCs did not show the full multipotency of BM-MSCs, their higher proliferative ability indicates that their cultivation would require less maintenance. Furthermore, the use of DMCs avoids the ethical concerns associated with the use of embryonic tissues, because they are derived from the maternal portion of the placenta, which is otherwise discarded. Thus, the unique properties of DMCs give them several advantages for clinical use, making them an interesting and

  6. Role of microRNA in epithelial to mesenchymal transition and metastasis and clinical perspectives

    Directory of Open Access Journals (Sweden)

    Díaz-López A

    2014-04-01

    Full Text Available Antonio Díaz-López,1 Gema Moreno-Bueno,1,2 Amparo Cano11Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigaciones Biomédicas “Alberto Sols” (CSIC-UAM, IdiPAZ, Madrid, Spain; 2Fundación MDAnderson Internacional, Madrid, SpainAbstract: The microRNAs (miRNAs are a class of small, 20–22 nucleotides in length, endogenously expressed noncoding RNAs that regulate multiple targets posttranscriptionally. Interestingly, miRNAs have emerged as regulators of most physiological and pathological processes, including metastatic tumor progression, in part by controlling a reversible process called epithelial-to-mesenchymal transition (EMT. The activation of EMT increases the migratory and invasive properties fundamental for tumor cell spread while activation of the reverse mesenchymal-to-epithelial transition is required for metastasis outgrowth. The EMT triggering leads to the activation of a core of transcription factors (EMT-TFs – SNAIL1/SNAIL2, bHLH (E47, E2-2, and TWIST1/TWIST2, and ZEB1/ZEB2 – that act as E-cadherin repressors and, ultimately, coordinate EMT. Recent evidence indicates that several miRNAs regulate the expression of EMT-TFs or EMT-activating signaling pathways. Interestingly, some miRNAs and EMT-TFs form tightly interconnected negative feedback loops that control epithelial cell plasticity, providing self-reinforcing signals and robustness to maintain the epithelial or mesenchymal cell status. Among the most significant feedback loops, we focus on the ZEB/miR-200 and the SNAIL1/miR-34 networks that hold a clear impact in the regulation of the epithelial-mesenchymal state. Recent insights into the p53 modulation of the EMT-TF/miRNA loops and epigenetic regulatory mechanisms in the context of metastasis dissemination will also be discussed. Understanding the regulation of EMT by miRNAs opens new avenues for the diagnosis and prognosis of tumors and identifies potential

  7. A fat option for the pig: Hepatocytic differentiated mesenchymal stem cells for translational research

    Energy Technology Data Exchange (ETDEWEB)

    Brückner, Sandra, E-mail: sandra.brueckner@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); Tautenhahn, Hans-Michael, E-mail: hans-michael.tautenhahn@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); TRM, Translational Centre for Regenerative Medicine, Philipp-Rosenthal-Str. 55, Leipzig D-04103 (Germany); Winkler, Sandra, E-mail: sandra.pelz@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); Stock, Peggy, E-mail: peggy.stock@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); Dollinger, Matthias, E-mail: matthias.dollinger@uniklinik-ulm.de [University Hospital Ulm, First Department of Medicine, Albert-Einstein-Allee 23, Ulm D-89081 (Germany); Christ, Bruno, E-mail: bruno.christ@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); TRM, Translational Centre for Regenerative Medicine, Philipp-Rosenthal-Str. 55, Leipzig D-04103 (Germany)

    2014-02-15

    Study background: Extended liver resection is the only curative treatment option of liver cancer. Yet, the residual liver may not accomplish the high metabolic and regenerative capacity needed, which frequently leads to acute liver failure. Because of their anti-inflammatory and -apoptotic as well as pro-proliferative features, mesenchymal stem cells differentiated into hepatocyte-like cells might provide functional and regenerative compensation. Clinical translation of basic research requires pre-clinical approval in large animals. Therefore, we characterized porcine mesenchymal stem cells (MSC) from adipose tissue and bone marrow and their hepatocyte differentiation potential for future assessment of functional liver support after surgical intervention in the pig model. Methods: Mesenchymal surface antigens and multi-lineage differentiation potential of porcine MSC isolated by collagenase digestion either from bone marrow or adipose tissue (subcutaneous/visceral) were assessed by flow cytometry. Morphology and functional properties (urea-, glycogen synthesis and cytochrome P450 activity) were determined during culture under differentiation conditions and compared with primary porcine hepatocytes. Results: MSC from porcine adipose tissue and from bone marrow express the typical mesenchymal markers CD44, CD29, CD90 and CD105 but not haematopoietic markers. MSC from both sources displayed differentiation into the osteogenic as well as adipogenic lineage. After hepatocyte differentiation, expression of CD105 decreased significantly and cells adopted the typical polygonal morphology of hepatocytes. Glycogen storage was comparable in adipose tissue- and bone marrow-derived cells. Urea synthesis was about 35% lower in visceral than in subcutaneous adipose tissue-derived MSC. Cytochrome P450 activity increased significantly during differentiation and was twice as high in hepatocyte-like cells generated from bone marrow as from adipose tissue. Conclusion: The hepatocyte

  8. A fat option for the pig: Hepatocytic differentiated mesenchymal stem cells for translational research

    International Nuclear Information System (INIS)

    Brückner, Sandra; Tautenhahn, Hans-Michael; Winkler, Sandra; Stock, Peggy; Dollinger, Matthias; Christ, Bruno

    2014-01-01

    Study background: Extended liver resection is the only curative treatment option of liver cancer. Yet, the residual liver may not accomplish the high metabolic and regenerative capacity needed, which frequently leads to acute liver failure. Because of their anti-inflammatory and -apoptotic as well as pro-proliferative features, mesenchymal stem cells differentiated into hepatocyte-like cells might provide functional and regenerative compensation. Clinical translation of basic research requires pre-clinical approval in large animals. Therefore, we characterized porcine mesenchymal stem cells (MSC) from adipose tissue and bone marrow and their hepatocyte differentiation potential for future assessment of functional liver support after surgical intervention in the pig model. Methods: Mesenchymal surface antigens and multi-lineage differentiation potential of porcine MSC isolated by collagenase digestion either from bone marrow or adipose tissue (subcutaneous/visceral) were assessed by flow cytometry. Morphology and functional properties (urea-, glycogen synthesis and cytochrome P450 activity) were determined during culture under differentiation conditions and compared with primary porcine hepatocytes. Results: MSC from porcine adipose tissue and from bone marrow express the typical mesenchymal markers CD44, CD29, CD90 and CD105 but not haematopoietic markers. MSC from both sources displayed differentiation into the osteogenic as well as adipogenic lineage. After hepatocyte differentiation, expression of CD105 decreased significantly and cells adopted the typical polygonal morphology of hepatocytes. Glycogen storage was comparable in adipose tissue- and bone marrow-derived cells. Urea synthesis was about 35% lower in visceral than in subcutaneous adipose tissue-derived MSC. Cytochrome P450 activity increased significantly during differentiation and was twice as high in hepatocyte-like cells generated from bone marrow as from adipose tissue. Conclusion: The hepatocyte

  9. Contact-impact algorithms on parallel computers

    International Nuclear Information System (INIS)

    Zhong Zhihua; Nilsson, Larsgunnar

    1994-01-01

    Contact-impact algorithms on parallel computers are discussed within the context of explicit finite element analysis. The algorithms concerned include a contact searching algorithm and an algorithm for contact force calculations. The contact searching algorithm is based on the territory concept of the general HITA algorithm. However, no distinction is made between different contact bodies, or between different contact surfaces. All contact segments from contact boundaries are taken as a single set. Hierarchy territories and contact territories are expanded. A three-dimensional bucket sort algorithm is used to sort contact nodes. The defence node algorithm is used in the calculation of contact forces. Both the contact searching algorithm and the defence node algorithm are implemented on the connection machine CM-200. The performance of the algorithms is examined under different circumstances, and numerical results are presented. ((orig.))

  10. Geometrical effects of conventional and digital prosthodontic planning wax-ups on lateral occlusal contact number, contact area, and steepness.

    Science.gov (United States)

    Abduo, Jaafar

    2017-01-01

    This study evaluated and compared the effect of conventional and digital wax-ups on three lateral occlusion variables: contact number, contact area, and steepness. Dental casts of 10 patients with Angle Class I relationship were included in the study. All patients required fixed prosthodontic treatment that would affect lateral occlusion. The casts of all patients received conventional and digital wax-ups. For pretreatment, conventional wax-up, and digital wax-up casts, contact number, contact area, and occlusion steepness were measured at four lateral positions, that is, at excursions of 0.5, 1.0, 2.0, and 3.0 mm from maximal intercuspation. Lateral occlusion scheme variables were affected by use of diagnostic wax-ups. For all types of casts, contact number decreased as excursion increased. The two types of wax-ups had similar contact number patterns, and contact number was significantly greater for these casts than for pretreatment casts in the earlier stages of excursion. Similarly, contact area gradually decreased with increasing excursion in the pretreatment and conventional and digital wax-up casts. There was only a minimal decrease in occlusion steepness as excursion increased. However, lateral occlusion was generally steeper for digital wax-up casts.

  11. Nonstimulated human uncommitted mesenchymal stem cells express cell markers of mesenchymal and neural lineages.

    Science.gov (United States)

    Minguell, José J; Fierro, Fernando A; Epuñan, María J; Erices, Alejandro A; Sierralta, Walter D

    2005-08-01

    Ex vivo cultures of human bone marrow-derived mesenchymal stem cells (MSCs) contain subsets of progenitors exhibiting dissimilar properties. One of these subsets comprises uncommitted progenitors displaying distinctive features, such as morphology, a quiescent condition, growth factor production, and restricted tissue biodistribution after transplantation. In this study, we assessed the competence of these cells to express, in the absence of differentiation stimuli, markers of mesoderm and ectodermic (neural) cell lineages. Fluorescence microscopy analysis showed a unique pattern of expression of osteogenic, chondrogenic, muscle, and neural markers. The depicted "molecular signature" of these early uncommitted progenitors, in the absence of differentiation stimuli, is consistent with their multipotentiality and plasticity as suggested by several in vitro and in vivo studies.

  12. Device including a contact detector

    DEFF Research Database (Denmark)

    2011-01-01

    arms (12) may extend from the supporting body in co-planar relationship with the first surface. The plurality of cantilever arms (12) may extend substantially parallel to each other and each of the plurality of cantilever arms (12) may include an electrical conductive tip for contacting the area......The present invention relates to a probe for determining an electrical property of an area of a surface of a test sample, the probe is intended to be in a specific orientation relative to the test sample. The probe may comprise a supporting body defining a first surface. A plurality of cantilever...... of the test sample by movement of the probe relative to the surface of the test sample into the specific orientation.; The probe may further comprise a contact detector (14) extending from the supporting body arranged so as to contact the surface of the test sample prior to any one of the plurality...

  13. All-graphene edge contacts

    DEFF Research Database (Denmark)

    Jacobsen, Kåre Wedel; Falkenberg, Jesper Toft; Papior, Nick Rübner

    2016-01-01

    Using ab-initio methods we investigate the possibility of three-terminalgraphene "T-junction" devices and show that these all-graphene edge contactsare energetically feasible when the 1D interface itself is free from foreignatoms. We examine the energetics of various junction structures as a func......Using ab-initio methods we investigate the possibility of three-terminalgraphene "T-junction" devices and show that these all-graphene edge contactsare energetically feasible when the 1D interface itself is free from foreignatoms. We examine the energetics of various junction structures...... to be in therange of 1-10 kΩμm which is comparable to the best contact resistance reportedfor edge-contacted graphene-metal contacts. We conclude that conductingall-carbon T-junctions should be feasible....

  14. Contact Lenses for Color Blindness.

    Science.gov (United States)

    Badawy, Abdel-Rahman; Hassan, Muhammad Umair; Elsherif, Mohamed; Ahmed, Zubair; Yetisen, Ali K; Butt, Haider

    2018-06-01

    Color vision deficiency (color blindness) is an inherited genetic ocular disorder. While no cure for this disorder currently exists, several methods can be used to increase the color perception of those affected. One such method is the use of color filtering glasses which are based on Bragg filters. While these glasses are effective, they are high cost, bulky, and incompatible with other vision correction eyeglasses. In this work, a rhodamine derivative is incorporated in commercial contact lenses to filter out the specific wavelength bands (≈545-575 nm) to correct color vision blindness. The biocompatibility assessment of the dyed contact lenses in human corneal fibroblasts and human corneal epithelial cells shows no toxicity and cell viability remains at 99% after 72 h. This study demonstrates the potential of the dyed contact lenses in wavelength filtering and color vision deficiency management. © 2018 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Methylisothiazolinone contact allergy - A review

    DEFF Research Database (Denmark)

    Lundov, M D; Krongaard, Teddy; L Menné, T

    2011-01-01

    In the early 2000s the preservative methylisothiazolinone (MI) was released as an individual preservative for industrial products and in 2005 permitted for use in cosmetic products. Up till then MI had only been used in combination with methylcholoroisthiazolinone (MCI). MCI/MI is one of the most...... frequent causes of preservative contact allergy and early studies showed that both MI and MCI are sensitizers. The prevalence of MI contact allergy is already around 1·5% and sources of exposure are associated with occupation, cosmetic products or household products. Use of MI in industrial products...... is not restricted and cases of occupational contact allergy to MI e.g. in painters are reported. The frequency of use of MI in cosmetics is low, around 1%, while up to 16·5% of household products were preserved with MI. We found 19 (1·5%) out of 1272 cosmetic products labelled with MI, primarily rinse-off products...

  16. Methylisothiazolinone contact allergy: a review

    DEFF Research Database (Denmark)

    Lundov, M D; Krongaard, T; Menné, T L

    2011-01-01

    In the early 2000s the preservative methylisothiazolinone (MI) was released as an individual preservative for industrial products and in 2005 permitted for use in cosmetic products. Up till then MI had only been used in combination with methylcholoroisthiazolinone (MCI). MCI/MI is one of the most...... frequent causes of preservative contact allergy and early studies showed that both MI and MCI are sensitizers. The prevalence of MI contact allergy is already around 1·5% and sources of exposure are associated with occupation, cosmetic products or household products. Use of MI in industrial products...... is not restricted and cases of occupational contact allergy to MI e.g. in painters are reported. The frequency of use of MI in cosmetics is low, around 1%, while up to 16·5% of household products were preserved with MI. We found 19 (1·5%) out of 1272 cosmetic products labelled with MI, primarily rinse-off products...

  17. Variable reluctance switch avoids contact corrosion and contact bounce

    Science.gov (United States)

    Watson, P. C.

    1967-01-01

    Variable reluctance switch avoids contact corrosion and bounce in a hostile environment. It consists of a wire-wound magnetic core and moveable bridge piece that alters the core flux pattern to produce an electrical output useful for switching control media.

  18. Homotopy classification of contact foliations on open contact manifolds

    Indian Academy of Sciences (India)

    64

    Let ξt, t ∈ [0, 1] be a continuous family of contact structures defined by the ... here is based on ideas that can be found in [5] and [8] and may be known to experts. ..... the bigger rectangle represents the set U ×Iε1 and the central dotted line.

  19. Contact Dynamics of EHL Contacts under Time Varying Conditions

    NARCIS (Netherlands)

    Venner, Cornelis H.; Popovici, G.; Wijnant, Ysbrand H.; Dalmaz, G.; Lubrecht, A.A.; Priest, M

    2004-01-01

    By means of numerical simulations of two situations with time varying operating conditions it is shown that the dynamic behaviour of Elasto-Hydrodynamically Lubricated contacts in terms of vibrations can be characterized as: Changes in the mutual approach lead to film thickness changes in the inlet

  20. Fragrance contact allergy in Iran.

    Science.gov (United States)

    Firooz, A; Nassiri-Kashani, M; Khatami, A; Gorouhi, F; Babakoohi, S; Montaser-Kouhsari, L; Davari, P; Dowlati, Y

    2010-12-01

    Fragrances are considered as one of the most common causes of allergic contact dermatitis. About 1-4% of the general population suffer from fragrance contact allergy (FCA). To determine the frequency of FCA and its clinical relevance in a sample of Iranian patients with history of contact and/or atopic dermatitis from January 2004 to December 2008. Standardized patch testing with 28-allergen screening series recommended by the German Contact Dermatitis Research Group and European Standard Series was used at six dermatological clinics in Iran. Fragrance allergens comprised of fragrance mix I (FM I), Myroxylon pereirae (MP; balsam of Peru), Lyral, turpentine and FM II. Fragrance contact allergy was detected in 7.2% of the patients. The frequency of positive reactions to FM I, MP and FM II were 3.7% (41/1105), 2.8% (32/1135) and 1.1% (3/267) respectively. 82.4% of the reactions to fragrance allergens were clinically relevant. The most common involved areas were hands (68.4%) and face (35.4%). Fragrance allergy predominantly affected women aged more than 40 years (P=0.008). Positive reaction to more than two allergens was significantly higher in FCA patients compared with other contact dermatitis patients (P<0.0001), and FM I, nickel and MP were the most frequent allergens in these patients. Despite less frequency of FCA in comparison with some European countries, its clinical relevance in Iranian patients seems to be high. It mostly affects the hands and the face predominantly in women aged more than 40 years. © 2010 The Authors. Journal compilation © 2010 European Academy of Dermatology and Venereology.

  1. Metal Contacts to Gallium Arsenide.

    Science.gov (United States)

    Ren, Fan

    1991-07-01

    While various high performance devices fabricated from the gallium arsenide (GaAs) and related materials have generated considerable interest, metallization are fundamental components to all semiconductor devices and integrated circuits. The essential roles of metallization systems are providing the desired electrical paths between the active region of the semiconductor and the external circuits through the metal interconnections and contacts. In this work, in-situ clean of native oxide, high temperature n-type, low temperature n-type and low temperature p-type ohmic metal systems have been studied. Argon ion mill was used to remove the native oxide prior to metal deposition. For high temperature process n-type GaAs ohmic contacts, Tungsten (W) and Tungsten Silicide (WSi) were used with an epitaxial grown graded Indium Gallium Arsenide (InGaAs) layer (0.2 eV) on GaAs. In addition, refractory metals, Molybdenum (Mo), was incorporated in the Gold-Germanium (AuGe) based on n-type GaAs ohmic contacts to replace conventional silver as barrier to prevent the reaction between ohmic metal and chlorine based plasma as well as the ohmic metallization intermixing which degrades the device performance. Finally, Indium/Gold-Beryllium (In/Au-Be) alloy has been developed as an ohmic contact for p-type GaAs to reduce the contact resistance. The Fermi-level pinning of GaAs has been dominated by the surface states. The Schottky barrier height of metal contacts are about 0.8 V regardless of the metal systems. By using p-n junction approach, barrier height of pulsed C-doped layers was achieved as high as 1.4 V. Arsenic implantation into GaAs method was also used to enhance the barrier height of 1.6 V.

  2. Clinical update on contact allergy

    DEFF Research Database (Denmark)

    Uter, Wolfgang; Johansen, Jeanne Duus; Orton, David I

    2005-01-01

    PURPOSE OF REVIEW: The aim of this article is to review recent findings in contact allergy, regarding clinical research. RECENT FINDINGS: The biocide methyldibromo glutaronitrile was identified to be an important sensitizer. Subsequently, it was banned from leave-on cosmetics in the European Union...... a classification of newly introduced chemicals; increasingly, the local lymph node assay is supplementing and potentially replacing the guinea pig maximization test. Recent advances in occupational contact allergy include, for example, some attempts to improve diagnostics for epoxy resin and other plastic, glue...

  3. CONTACT DERMATITIS AMONG CONSTRUCTION WORKERS

    Directory of Open Access Journals (Sweden)

    Ida Ayu Diah Purnama Sari

    2013-02-01

    Full Text Available Contact dermatitis is a form of skin inflammation with spongiosis or intercellular edema of the epidermis due to the interaction of irritants and allergens. While occupational contact dermatitis is an inflammation of the skin due to exposure to irritants or allergens in the workplace. One of the jobs that have a high risk of the disease are construction workers. Although the disease is rarely-threatening but can cause high morbidity and suffering for workers, so it can affect the economy and quality of life of patients.

  4. Altered features and increased chemosensitivity of human breast cancer cells mediated by adipose tissue-derived mesenchymal stromal cells

    International Nuclear Information System (INIS)

    Kucerova, Lucia; Skolekova, Svetlana; Matuskova, Miroslava; Bohac, Martin; Kozovska, Zuzana

    2013-01-01

    Mesenchymal stromal cells (MSCs) represent heterogeneous cell population suitable for cell therapies in regenerative medicine. MSCs can also substantially affect tumor biology due to their ability to be recruited to the tumor stroma and interact with malignant cells via direct contacts and paracrine signaling. The aim of our study was to characterize molecular changes dictated by adipose tissue-derived mesenchymal stromal cells (AT-MSCs) and the effects on drug responses in human breast cancer cells SKBR3. The tumor cells were either directly cocultured with AT-MSCs or exposed to MSCs-conditioned medium (MSC-CM). Changes in cell biology were evaluated by kinetic live cell imaging, fluorescent microscopy, scratch wound assay, expression analysis, cytokine secretion profiling, ATP-based viability and apoptosis assays. The efficiency of cytotoxic treatment in the presence of AT-MSCs or MSCs-CM was analyzed. The AT-MSCs altered tumor cell morphology, induced epithelial-to-mesenchymal transition, increased mammosphere formation, cell confluence and migration of SKBR3. These features were attributed to molecular changes induced by MSCs-secreted cytokines and chemokines in breast cancer cells. AT-MSCs significantly inhibited the proliferation of SKBR3 cells in direct cocultures which was shown to be dependent on the SDF-1α/CXCR4 signaling axis. MSC-CM-exposed SKBR3 or SKBR3 in direct coculture with AT-MSCs exhibited increased chemosensitivity and induction of apoptosis in response to doxorubicin and 5-fluorouracil. Our work further highlights the multi-level nature of tumor-stromal cell interplay and demonstrates the capability of AT-MSCs and MSC-secreted factors to alter the anti-tumor drug responses

  5. Characterization of bone marrow-derived mesenchymal stem cells in aging.

    Science.gov (United States)

    Baker, Natasha; Boyette, Lisa B; Tuan, Rocky S

    2015-01-01

    Adult mesenchymal stem cells are a resource for autologous and allogeneic cell therapies for immune-modulation and regenerative medicine. However, patients most in need of such therapies are often of advanced age. Therefore, the effects of the aged milieu on these cells and their intrinsic aging in vivo are important considerations. Furthermore, these cells may require expansion in vitro before use as well as for future research. Their aging in vitro is thus also an important consideration. Here, we focus on bone marrow mesenchymal stem cells (BMSCs), which are unique compared to other stem cells due to their support of hematopoietic cells in addition to contributing to bone formation. BMSCs may be sensitive to age-related diseases and could perpetuate degenerative diseases in which bone remodeling is a contributory factor. Here, we review (1) the characterization of BMSCs, (2) the characterization of in vivo-aged BMSCs, (3) the characterization of in vitro-aged BMSCs, and (4) potential approaches to optimize the performance of aged BMSCs. This article is part of a Special Issue entitled "Stem Cells and Bone". Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Mesenchymal stem cell adhesion but not plasticity is affected by high substrate stiffness

    Directory of Open Access Journals (Sweden)

    Janice Kal Van Tam, Koichiro Uto, Mitsuhiro Ebara, Stefania Pagliari, Giancarlo Forte and Takao Aoyagi

    2012-01-01

    Full Text Available The acknowledged ability of synthetic materials to induce cell-specific responses regardless of biological supplies provides tissue engineers with the opportunity to find the appropriate materials and conditions to prepare tissue-targeted scaffolds. Stem and mature cells have been shown to acquire distinct morphologies in vitro and to modify their phenotype when grown on synthetic materials with tunable mechanical properties. The stiffness of the substrate used for cell culture is likely to provide cells with mechanical cues mimicking given physiological or pathological conditions, thus affecting the biological properties of cells. The sensitivity of cells to substrate composition and mechanical properties resides in multiprotein complexes called focal adhesions, whose dynamic modification leads to cytoskeleton remodeling and changes in gene expression. In this study, the remodeling of focal adhesions in human mesenchymal stem cells in response to substrate stiffness was followed in the first phases of cell–matrix interaction, using poly-ε-caprolactone planar films with similar chemical composition and different elasticity. As compared to mature dermal fibroblasts, mesenchymal stem cells showed a specific response to substrate stiffness, in terms of adhesion, as a result of differential focal adhesion assembly, while their multipotency as a bulk was not significantly affected by matrix compliance. Given the sensitivity of stem cells to matrix mechanics, the mechanobiology of such cells requires further investigations before preparing tissue-specific scaffolds.

  7. Usage of Human Mesenchymal Stem Cells in Cell-based Therapy: Advantages and Disadvantages.

    Science.gov (United States)

    Kim, Hee Jung; Park, Jeong-Soo

    2017-03-01

    The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed.

  8. Brain mesenchymal stem cells: The other stem cells of the brain?

    Science.gov (United States)

    Appaix, Florence; Nissou, Marie-France; van der Sanden, Boudewijn; Dreyfus, Matthieu; Berger, François; Issartel, Jean-Paul; Wion, Didier

    2014-04-26

    Multipotent mesenchymal stromal cells (MSC), have the potential to differentiate into cells of the mesenchymal lineage and have non-progenitor functions including immunomodulation. The demonstration that MSCs are perivascular cells found in almost all adult tissues raises fascinating perspectives on their role in tissue maintenance and repair. However, some controversies about the physiological role of the perivascular MSCs residing outside the bone marrow and on their therapeutic potential in regenerative medicine exist. In brain, perivascular MSCs like pericytes and adventitial cells, could constitute another stem cell population distinct to the neural stem cell pool. The demonstration of the neuronal potential of MSCs requires stringent criteria including morphological changes, the demonstration of neural biomarkers expression, electrophysiological recordings, and the absence of cell fusion. The recent finding that brain cancer stem cells can transdifferentiate into pericytes is another facet of the plasticity of these cells. It suggests that the perversion of the stem cell potential of pericytes might play an even unsuspected role in cancer formation and tumor progression.

  9. Cell-based delivery of glucagon-like peptide-1 using encapsulated mesenchymal stem cells.

    Science.gov (United States)

    Wallrapp, Christine; Thoenes, Eric; Thürmer, Frank; Jork, Anette; Kassem, Moustapha; Geigle, Peter

    2013-01-01

    Glucagon-like peptide-1 (GLP-1) CellBeads are cell-based implants for the sustained local delivery of bioactive factors. They consist of GLP-1 secreting mesenchymal stem cells encapsulated in a spherically shaped immuno-isolating alginate matrix. A highly standardized and reproducible encapsulation method is described for the manufacturing of homogeneous CellBeads. Viability and sustained secretion was shown for the recombinant GLP-1 and the cell endogenous bioactive factors like vascular endothelial growth factor, neurotrophin 3 (NT-3) and glial cell line-derived neurotrophic factor. Manufacturing and quality control is performed in compliance with good manufacturing practice and fulfils all regulatory requirements for human clinical use. GLP-1 CellBeads combine the neuro- and cardioprotective properties of both GLP-1 and mesenchymal stem cells. First promising results were obtained from preclinical studies and an ongoing safety trial in humans but further studies have to prove the overall potential of CellBead technology in cell-based regenerative medicine.

  10. Platelet lysate as replacement for fetal bovine serum in mesenchymal stromal cell cultures.

    Science.gov (United States)

    Bieback, Karen

    2013-10-01

    Mesenchymal stromal cells (MSC) emerged as highly attractive in cell-based regenerative medicine. Initially thought to provide cells capable of differentiation towards mesenchymal cell types (osteoblasts, chondrocytes, adipocytes etc.), by and by potent immunoregulatory and pro-regenerative activities have been discovered, broadening the field of potential applications from bone and cartilage regeneration to wound healing and treatment of autoimmune diseases. Due to the limited frequency in most tissue sources, ex vivo expansion of MSC is required compliant with good manufacturing practice (GMP) guidelines to yield clinically relevant cell doses. Though, still most manufacturing protocols use fetal bovine serum (FBS) as cell culture supplement to isolate and to expand MSC. However, the high lot-to-lot variability as well as risk of contamination and immunization call for xenogenic-free culture conditions. In terms of standardization, chemically defined media appear as the ultimate achievement. Since these media need to maintain all key cellular and therapy-relevant features of MSC, the development of chemically defined media is still - albeit highly investigated - only in its beginning. The current alternatives to FBS rely on human blood-derived components: plasma, serum, umbilical cord blood serum, and platelet derivatives like platelet lysate. Focusing on quality aspects, the latter will be addressed within this review.

  11. Biodistribution of Liver-Derived Mesenchymal Stem Cells After Peripheral Injection in a Hemophilia A Patient.

    Science.gov (United States)

    Sokal, Etienne M; Lombard, Catherine Anne; Roelants, Véronique; Najimi, Mustapha; Varma, Sharat; Sargiacomo, Camillo; Ravau, Joachim; Mazza, Giuseppe; Jamar, François; Versavau, Julia; Jacobs, Vanessa; Jacquemin, Marc; Eeckhoudt, Stéphane; Lambert, Catherine; Stéphenne, Xavier; Smets, Françoise; Hermans, Cédric

    2017-08-01

    With the exception of liver transplantation, there is no cure for hemophilia, which is currently managed by preemptive replacement therapy. Liver-derived stem cells are in clinical development for inborn and acquired liver diseases and could represent a curative treatment for hemophilia A. The liver is a major factor VIII (FVIII) synthesis site, and mesenchymal stem cells have been shown to control joint bleeding in animal models of hemophilia. Adult-derived human liver stem cells (ADHLSCs) have mesenchymal characteristics and have been shown able to engraft in and repopulate both animal and human livers. Thus, the objectives were to evaluate the potency of ADHLSCs to control bleeding in a hemophilia A patient and assess the biodistribution of the cells after intravenous injection. A patient suffering from hemophilia A was injected with repeated doses of ADHLSCs via a peripheral vein (35 million In-oxine-labeled cells, followed by 125 million cells the next day, and 3 infusions of 250 million cells every 2 weeks thereafter; total infusion period, 50 days). After cell therapy, we found a temporary (15 weeks) decrease in the patient's FVIII requirements and severe bleeding complications, despite a lack of increase in circulating FVIII. The cells were safely administered to the patient via a peripheral vein. Biodistribution analysis revealed an initial temporary entrapment of the cells in the lungs, followed by homing to the liver and to a joint afflicted with hemarthrosis. These results suggest the potential use of ADHLSCs in the treatment of hemophilia A.

  12. Role of RHEB in Regulating Differentiation Fate of Mesenchymal Stem Cells for Cartilage and Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Sajjad Ashraf

    2017-04-01

    Full Text Available Advances in mesenchymal stem cells (MSCs and cell replacement therapies are promising approaches to treat cartilage and bone defects since substantial differentiation capacities of MSCs match the demands of tissue regeneration. Our understanding of the dynamic process requiring indispensable differentiation of MSCs remains limited. Herein, we describe the role of RHEB (Ras homolog enriched in brain regulating gene signature for differentiation of human adipose derived mesenchymal stem cells (ASCs into chondrogenic, osteogenic, and adipogenic lineages. RHEB-overexpression increases the proliferation of the ASCs. RHEB enhances the chondrogenic differentiation of ASCs in 3D culture via upregulation of SOX9 with concomitant increase in glycosaminoglycans (GAGs, and type II collagen (COL2. RHEB increases the osteogenesis via upregulation of runt related transcription factor 2 (RUNX2 with an increase in the calcium and phosphate contents. RHEB also increases the expression of osteogenic markers, osteonectin and osteopontin. RHEB knockdown ASCs were incapable of expressing sufficient SRY (Sex determining region Y-box 9 (SOX9 and RUNX2, and therefore had decreased chondrogenic and osteogenic differentiation. RHEB-overexpression impaired ASCs differentiation into adipogenic lineage, through downregulation of CCAAT/enhancer binding protein beta (C/EBPβ. Conversely, RHEB knockdown abolished the negative regulation of adipogenesis. We demonstrate that RHEB is a novel regulator, with a critical role in ASCs lineage determination, and RHEB-modulated ASCs may be useful as a cell therapy for cartilage and bone defect treatments.

  13. Loss of breast epithelial marker hCLCA2 promotes epithelial to mesenchymal transition and indicates higher risk of metastasis

    Science.gov (United States)

    Walia, Vijay; Yu, Yang; Cao, Deshou; Sun, Miao; McLean, Janel R.; Hollier, Brett G.; Cheng, Jiming; Mani, Sendurai A.; Rao, Krishna; Premkumar, Louis; Elble, Randolph

    2013-01-01

    Transition between epithelial and mesenchymal states is a feature of both normal development and tumor progression. We report that expression of chloride channel accessory protein hCLCA2 is a characteristic of epithelial differentiation in the immortalized MCF10A and HMLE models, while induction of EMT by cell dilution, TGFbeta, or mesenchymal transcription factors sharply reduces hCLCA2 levels. Attenuation of hCLCA2 expression by lentiviral shRNA caused cell overgrowth and focus formation, enhanced migration and invasion, and increased mammosphere formation in methylcellulose. These changes were accompanied by downregulation of E-cadherin and upregulation of mesenchymal markers such as vimentin and fibronectin. Moreover, hCLCA2 expression is greatly downregulated in breast cancer cells with a mesenchymal or claudin-low profile. These observations suggest that loss of hCLCA2 may promote metastasis. We find that higher-than-median expression of hCLCA2 is associated with a one-third lower rate of metastasis over an 18 year period among breast cancer patients compared to lower-than-median (n=344, unfiltered for subtype). Thus, hCLCA2 is required for epithelial differentiation, and its loss during tumor progression contributes to metastasis. Overexpression of hCLCA2 has been reported to inhibit cell proliferation and is accompanied by increases in chloride current at the plasma membrane and reduced intracellular pH (pHi). We found that knockdown cells have sharply reduced chloride current and higher pHi, both characteristics of tumor cells. These results suggest a mechanism for the effects on differentiation. Loss of hCLCA2 may allow escape from pHi homeostatic mechanisms, permitting the higher intracellular and lower extracellular pH that are characteristic of aggressive tumor cells. PMID:21909135

  14. An analytical method for computing atomic contact areas in biomolecules.

    Science.gov (United States)

    Mach, Paul; Koehl, Patrice

    2013-01-15

    We propose a new analytical method for detecting and computing contacts between atoms in biomolecules. It is based on the alpha shape theory and proceeds in three steps. First, we compute the weighted Delaunay triangulation of the union of spheres representing the molecule. In the second step, the Delaunay complex is filtered to derive the dual complex. Finally, contacts between spheres are collected. In this approach, two atoms i and j are defined to be in contact if their centers are connected by an edge in the dual complex. The contact areas between atom i and its neighbors are computed based on the caps formed by these neighbors on the surface of i; the total area of all these caps is partitioned according to their spherical Laguerre Voronoi diagram on the surface of i. This method is analytical and its implementation in a new program BallContact is fast and robust. We have used BallContact to study contacts in a database of 1551 high resolution protein structures. We show that with this new definition of atomic contacts, we generate realistic representations of the environments of atoms and residues within a protein. In particular, we establish the importance of nonpolar contact areas that complement the information represented by the accessible surface areas. This new method bears similarity to the tessellation methods used to quantify atomic volumes and contacts, with the advantage that it does not require the presence of explicit solvent molecules if the surface of the protein is to be considered. © 2012 Wiley Periodicals, Inc. Copyright © 2012 Wiley Periodicals, Inc.

  15. MRI appearance of mesenchymal tumors of the uterus

    Energy Technology Data Exchange (ETDEWEB)

    Cornfeld, Daniel [Department of Diagnostic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510 (United States)], E-mail: daniel.cornfeld@yale.edu; Israel, Gary [Department of Diagnostic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510 (United States); Martel, Maritza [Department of Pathology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510 (United States); Weinreb, Jeffery [Department of Diagnostic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510 (United States); Schwartz, Peter [Department of Obstetrics and Gynecology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510 (United States); McCarthy, Shirley [Department of Diagnostic Radiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510 (United States)

    2010-04-15

    Purpose: Uterine leiomyomas are the most common uterine neoplasms. Statistically, a uterine mass with unusual imaging features is more likely to represent a leiomyoma than other uncommon uterine mesenchymal neoplasms such as leiomyosarcoma or endometrial stromal tumors. Several prior studies have attempted to identify objective imaging characteristics that differentiate these entities. The purpose of this study was to test these criteria on our patient population. Methods and materials: This retrospective study was approved by the institutional Human Investigations Committee and was performed in compliance with HIPAA regulations. Four patients with uterine leiomyosarcoma, two with stromal tumors of uncertain malignant potential (STUMP), one with endometrial stromal sarcoma, and two with mixed endometrial stromal and smooth muscle tumors were included in the study. Seventeen additional control cases of leiomyomas were selected as controls. Cases were blindly evaluated by two experienced readers. Objective criteria included T1 and T2 signal characteristics, enhancement pattern, the presence of cystic changes, and ill defined margins. Subjective criteria included individual reader gestalt. All cases had pathologic correlation. Results: None of the objective criteria were associated with the presence or absence of uterine mesenchymal neoplasm. Ill defined margins came closest to having statistical significance (p = 0.06). Reader gestalt was statistically associated with the presence of mesenchymal neoplasm for one of our readers (p = 0.02) but not for the other (p = 0.07). Conclusion: We found poor accuracy for objective imaging criteria in distinguishing leiomyomas with atypical imaging features from more clinically significant uterine mesenchymal neoplasms.

  16. MRI appearance of mesenchymal tumors of the uterus

    International Nuclear Information System (INIS)

    Cornfeld, Daniel; Israel, Gary; Martel, Maritza; Weinreb, Jeffery; Schwartz, Peter; McCarthy, Shirley

    2010-01-01

    Purpose: Uterine leiomyomas are the most common uterine neoplasms. Statistically, a uterine mass with unusual imaging features is more likely to represent a leiomyoma than other uncommon uterine mesenchymal neoplasms such as leiomyosarcoma or endometrial stromal tumors. Several prior studies have attempted to identify objective imaging characteristics that differentiate these entities. The purpose of this study was to test these criteria on our patient population. Methods and materials: This retrospective study was approved by the institutional Human Investigations Committee and was performed in compliance with HIPAA regulations. Four patients with uterine leiomyosarcoma, two with stromal tumors of uncertain malignant potential (STUMP), one with endometrial stromal sarcoma, and two with mixed endometrial stromal and smooth muscle tumors were included in the study. Seventeen additional control cases of leiomyomas were selected as controls. Cases were blindly evaluated by two experienced readers. Objective criteria included T1 and T2 signal characteristics, enhancement pattern, the presence of cystic changes, and ill defined margins. Subjective criteria included individual reader gestalt. All cases had pathologic correlation. Results: None of the objective criteria were associated with the presence or absence of uterine mesenchymal neoplasm. Ill defined margins came closest to having statistical significance (p = 0.06). Reader gestalt was statistically associated with the presence of mesenchymal neoplasm for one of our readers (p = 0.02) but not for the other (p = 0.07). Conclusion: We found poor accuracy for objective imaging criteria in distinguishing leiomyomas with atypical imaging features from more clinically significant uterine mesenchymal neoplasms.

  17. The life and fate of mesenchymal stem cells

    NARCIS (Netherlands)

    E. Eggenhofer (Elke); F. Luk (Franka); M.H. Dahlke (Marc); M.J. Hoogduijn (Martin)

    2014-01-01

    textabstractMesenchymal stem cells (MSC) are present throughout the body and are thought to play a role in tissue regeneration and control of inflammation. MSC can be easily expanded in vitro and their potential as a therapeutic option for degenerative and inflammatory disease is therefore

  18. Case report 517: Mesenchymal chondrosarcoma of the femur

    International Nuclear Information System (INIS)

    Bertoni, F.; Bacchini, P.; Picci, P.; Gherlinzoni, F.

    1989-01-01

    This case confirms that mesenchymal chondrosarcoma, a highly malignant tumor, may have a protracted clinical course. The radiographic presentation, as in this case, may be misleading since the small size of the lesion and the apparently well marginated lytic zone could easily suggest a benign lesion. (orig./GDG)

  19. FGF9 can induce endochondral ossification in cranial mesenchyme

    Directory of Open Access Journals (Sweden)

    Overbeek Paul A

    2006-02-01

    Full Text Available Abstract Background The flat bones of the skull (i.e., the frontal and parietal bones normally form through intramembranous ossification. At these sites cranial mesenchymal cells directly differentiate into osteoblasts without the formation of a cartilage intermediate. This type of ossification is distinct from endochondral ossification, a process that involves initial formation of cartilage and later replacement by bone. Results We have analyzed a line of transgenic mice that expresses FGF9, a member of the fibroblast growth factor family (FGF, in cranial mesenchymal cells. The parietal bones in these mice show a switch from intramembranous to endochondral ossification. Cranial cartilage precursors are induced to proliferate, then hypertrophy and are later replaced by bone. These changes are accompanied by upregulation of Sox9, Ihh, Col2a1, Col10a1 and downregulation of CbfaI and Osteocalcin. Fate mapping studies show that the cranial mesenchymal cells in the parietal region that show a switch in cell fate are likely to be derived from the mesoderm. Conclusion These results demonstrate that FGF9 expression is sufficient to convert the differentiation program of (at least a subset of mesoderm-derived cranial mesenchyme cells from intramembranous to endochondral ossification.

  20. Mesenchymal stem cells for the treatment of tendon disorders

    Czech Academy of Sciences Publication Activity Database

    Machová-Urdzíková, Lucia; Lesný, Petr; Syková, Eva; Jendelová, Pavla

    2013-01-01

    Roč. 6, 8A (2013), s. 14-23 ISSN 1937-6871 R&D Projects: GA ČR GAP304/10/0326 Institutional support: RVO:68378041 Keywords : Tendinophaty * Mesenchymal Stem Cells * Tendon Rupture Subject RIV: FP - Other Medical Disciplines

  1. Invited review: mesenchymal progenitor cells in intramuscular connective tissue development.

    Science.gov (United States)

    Miao, Z G; Zhang, L P; Fu, X; Yang, Q Y; Zhu, M J; Dodson, M V; Du, M

    2016-01-01

    The abundance and cross-linking of intramuscular connective tissue contributes to the background toughness of meat, and is thus undesirable. Connective tissue is mainly synthesized by intramuscular fibroblasts. Myocytes, adipocytes and fibroblasts are derived from a common pool of progenitor cells during the early embryonic development. It appears that multipotent mesenchymal stem cells first diverge into either myogenic or non-myogenic lineages; non-myogenic mesenchymal progenitors then develop into the stromal-vascular fraction of skeletal muscle wherein adipocytes, fibroblasts and derived mesenchymal progenitors reside. Because non-myogenic mesenchymal progenitors mainly undergo adipogenic or fibrogenic differentiation during muscle development, strengthening progenitor proliferation enhances the potential for both intramuscular adipogenesis and fibrogenesis, leading to the elevation of both marbling and connective tissue content in the resulting meat product. Furthermore, given the bipotent developmental potential of progenitor cells, enhancing their conversion to adipogenesis reduces fibrogenesis, which likely results in the overall improvement of marbling (more intramuscular adipocytes) and tenderness (less connective tissue) of meat. Fibrogenesis is mainly regulated by the transforming growth factor (TGF) β signaling pathway and its regulatory cascade. In addition, extracellular matrix, a part of the intramuscular connective tissue, provides a niche environment for regulating myogenic differentiation of satellite cells and muscle growth. Despite rapid progress, many questions remain in the role of extracellular matrix on muscle development, and factors determining the early differentiation of myogenic, adipogenic and fibrogenic cells, which warrant further studies.

  2. The role of bone marrow derived mesenchymal stem cells in ...

    African Journals Online (AJOL)

    Stroke is the third most common cause of death, and a leading cause of physical disability in adults. Recovery after a major stroke is usually limited, but cell therapy, especially by application of mesenchymal stem cells (MSCs) is emerging with fixed neurologic deficits. The aim of the current study was directed to isolation ...

  3. Human bone marrow-derived mesenchymal stem cells | Nasef ...

    African Journals Online (AJOL)

    Mesenchymal stem cells (MSCs) have elicited a great clinical interest, particularly in the areas of regenerative medicine and induction of tolerance in allogeneic transplantation. Previous reports demonstrated the feasibility of transplanting MSCs, which generates new prospects in cellular therapy. Recently, injection of ...

  4. In vitro differentiation of human umbilical cord blood mesenchymal ...

    African Journals Online (AJOL)

    Mesenchymal stem cells (MSCs) were isolated by gradient density centrifugation from umbilical cord blood. Spindle-shaped adherent cells were permitted to grow to 70% confluence in primary culture media which was reached by day 12. Induction of differentiation started by culturing cells with differentiation medium ...

  5. white leghorn chimeras based on bone marrow mesenchymal stem

    African Journals Online (AJOL)

    stem cells (BMMSCs), and to assess its immune tolerance based on variations in proportion of ... Keywords: Bone marrow mesenchymal stem cells, Immune tolerance, ... in tissue injury, transplantation, and ..... 0.05, **p < 0.01; (b) expression of the duck gene in different organs .... CD30hi Marek's disease lymphoma cell.

  6. Cytoskeletal Reorganization Drives Mesenchymal Condensation and Regulates Downstream Molecular Signaling.

    Directory of Open Access Journals (Sweden)

    Poulomi Ray

    Full Text Available Skeletal condensation occurs when specified mesenchyme cells self-organize over several days to form a distinctive cartilage template. Here, we determine how and when specified mesenchyme cells integrate mechanical and molecular information from their environment, forming cartilage condensations in the pharyngeal arches of chick embryos. By disrupting cytoskeletal reorganization, we demonstrate that dynamic cell shape changes drive condensation and modulate the response of the condensing cells to Fibroblast Growth Factor (FGF, Bone Morphogenetic Protein (BMP and Transforming Growth Factor beta (TGF-β signaling pathways. Rho Kinase (ROCK-driven actomyosin contractions and Myosin II-generated differential cell cortex tension regulate these cell shape changes. Disruption of the condensation process inhibits the differentiation of the mesenchyme cells into chondrocytes, demonstrating that condensation regulates the fate of the mesenchyme cells. We also find that dorsal and ventral condensations undergo distinct cell shape changes. BMP signaling is instructive for dorsal condensation-specific cell shape changes. Moreover, condensations exhibit ventral characteristics in the absence of BMP signaling, suggesting that in the pharyngeal arches ventral morphology is the ground pattern. Overall, this study characterizes the interplay between cytoskeletal dynamics and molecular signaling in a self-organizing system during tissue morphogenesis.

  7. Endogenous collagen influences differentiation of human multipotent mesenchymal stromal cells

    NARCIS (Netherlands)

    Fernandes, H.; Mentink, A.; Bank, R.; Stoop, R.; Blitterswijk, C. van; Boer, J. de

    2010-01-01

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix

  8. Growth and metabolism of mesenchymal stem cells cultivated on microcarriers

    NARCIS (Netherlands)

    Schop, Deborah

    2010-01-01

    Mesenchymal stem cells, MSCs, are a great potential source for clinical applications in the field of tissue regeneration. Although MSCs can be isolated from several tissues of the human body, e.g. the bone marrow, the tissues does not contain clinically relevant amounts of MSCs for cell therapeutic

  9. Endogenous Collagen Influences Differentiation of Human Multipotent Mesenchymal Stromal Cells

    NARCIS (Netherlands)

    Fernandes, Hugo; Mentink, Anouk; Bank, Ruud; Stoop, Reinout; van Blitterswijk, Clemens; de Boer, Jan

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix

  10. Endogenous Collagen Influences Differentiation of Human Multipotent Mesenchymal Stromal Cells

    NARCIS (Netherlands)

    Fernandes, H.A.M.; Mentink-Leusink, Anouk; Bank, Ruud; Stoop, Reinout; van Blitterswijk, Clemens; de Boer, Jan

    2010-01-01

    Human multipotent mesenchymal stromal cells (hMSCs) are multipotent cells that, in the presence of appropriate stimuli, can differentiate into different lineages such as the osteogenic, chondrogenic, and adipogenic lineages. In the presence of ascorbic acid, MSCs secrete an extracellular matrix

  11. Human mesenchymal stromal cells : biological characterization and clinical application

    NARCIS (Netherlands)

    Bernardo, Maria Ester

    2010-01-01

    This thesis focuses on the characterization of the biological and functional properties of human mesenchymal stromal cells (MSCs), isolated from different tissue sources. The differentiation capacity of MSCs from fetal and adult tissues has been tested and compared. Umbilical cord blood (UCB) has

  12. Amniocar as a proliferative medium for mesenchymal cells

    Directory of Open Access Journals (Sweden)

    V. V. Chestkov

    2014-01-01

    Full Text Available Objectives. To develop the Amniocar nutrient medium that contains fetal calf serum (FCS and growth factors cocktail for mass cultivation of human fibroblasts. To study proliferative activity of the medium on cultures of HUVEC cells of mesenchymal origin and mesenchymal stromal cells, as well as on cell culture of human amniotic fluid.Materials and methods. Determination of the rate of accumulation of the cellular mass and cell morphology in the course of cultivation of cells of various histogenesis in the Amniocar medium and nutrient medium that contains 10 % of FCS.Results. It has been demonstrated that the Amniocar medium is prevalent as compared to the standard DMEM medium with 10 % of FCS by 2 to 5 times for cultivation of skin fibroblasts, HUVEC, and mesenchymal stem cells. The Amniocar medium increased the quantity of endothelial cells that enter mitosis and maintained the culture of HUVEC cells with prolonged passaging in vitro. Clonal cultivation of human amniotic fluid cells in the Amniocar medium secured development of colonies of both fibroblast and epithelial type.Conclusions. Proliferative Amniocar medium is efficient for mass cultivation of various cells of mesenchymal origin and can be used for diagnostic purposes in medical genetics, oncology, etc.

  13. Placental mesenchymal dysplasia: case report with gross and histological findings.

    Science.gov (United States)

    Toscano, Marcello Pecoraro; Schultz, Regina

    2014-01-01

    Placental mesenchymal dysplasia (PMD) is a rare placental disorder characterized by placental enlargement and areas of abnormal, enlarged, grape-like villi. This condition may resemble a partial hydatidiform mole and may occur associated with Beckwith-Wiedemann syndrome (BWS) or in phenotypically normal fetuses. There were 110 cases reported so far. We describe one case with typical gross and microscopic placental lesions.

  14. Placental mesenchymal dysplasia: case report with gross and histological findings

    OpenAIRE

    Marcello Pecoraro Toscano; Regina Schultz

    2014-01-01

    Placental mesenchymal dysplasia (PMD) is a rare placental disorder characterized by placental enlargement and areas of abnormal, enlarged, grape-like villi. This condition may resemble a partial hydatidiform mole and may occur associated with Beckwith?Wiedemann syndrome (BWS) or in phenotypically normal fetuses. There were 110 cases reported so far. We describe one case with typical gross and microscopic placental lesions.

  15. Biomaterials Influence Macrophage-Mesenchymal Stem Cell Interaction In Vitro

    NARCIS (Netherlands)

    N. Grotenhuis (Nienke); S.F. De Witte (Samantha Fh); G.J.V.M. van Osch (Gerjo); Y. Bayon (Yves); J.F. Lange (Johan); Y.M. Bastiaansen-Jenniskens (Yvonne)

    2016-01-01

    textabstractBackground: Macrophages and mesenchymal stem cells (MSCs) are important cells in wound healing. We hypothesized that the cross-talk between macrophages and adipose tissue-derived MSCs (ASCs) is biomaterial dependent, thereby influencing processes involved in wound healing. Materials and

  16. Human bone-marrow-derived mesenchymal stem cells

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Abdallah, Basem M

    2008-01-01

    Mesenchymal stem cells (MSC) are a group of cells present in bone-marrow stroma and the stroma of various organs with the capacity for mesoderm-like cell differentiation into, for example, osteoblasts, adipocytes, and chondrocytes. MSC are being introduced in the clinic for the treatment...

  17. Proteomic techniques for characterisation of mesenchymal stem cell secretome.

    Czech Academy of Sciences Publication Activity Database

    Kupcová Skalníková, Helena

    2013-01-01

    Roč. 95, č. 12 (2013), s. 2196-2211 ISSN 0300-9084 R&D Projects: GA MŠk ED2.1.00/03.0124; GA TA ČR TA01011466 Institutional support: RVO:67985904 Keywords : mesenchymal stem cells * secretome * exosome * conditioned medium * proteomics Subject RIV: CE - Biochemistry Impact factor: 3.123, year: 2013

  18. The safety and efficacy of contact lens wear in the industrial and chemical workplace.

    Science.gov (United States)

    Tyhurst, Keith; McNett, Ryan; Bennett, Edward

    2007-11-01

    The use and safety of contact lenses in the industrial and chemical workplace has often been questioned since the 1960s because of many unconfirmed reports of ocular injury resulting from contact lens wear. Because of these urban legends, contact lens wear has been banned or wearers have been required to wear additional personal protective equipment (PPE) not required of non-contact lens wearers. Literature review via Medline and Google search. Research has shown that contact lenses typically provide protective benefits that decrease the severity of ocular injury and improve worker performance. While contact lens wear contraindications do exist, in most cases, and with proper precautions, contact lens wear is still possible. Industrial and chemical companies need to establish written contact lens use policies based on current studies that have shown the safety of workplace contact lens wear when combined with the same PPE required of non-contact lens wearers. Practitioners need to discuss, with their contact lens patients, the additional responsibilities required to maintain proper lens hygiene and proper PPE in the workplace.

  19. Autologous Mesenchymal Stem Cells in Chronic Stroke

    Directory of Open Access Journals (Sweden)

    Ashu Bhasin

    2011-12-01

    Full Text Available Background: Cell transplantation is a ‘hype and hope’ in the current scenario. It is in the early stage of development with promises to restore function in chronic diseases. Mesenchymal stem cell (MSC transplantation in stroke patients has shown significant improvement by reducing clinical and functional deficits. They are feasible and multipotent and have homing characteristics. This study evaluates the safety, feasibility and efficacy of autologous MSC transplantation in patients with chronic stroke using clinical scores and functional imaging (blood oxygen level-dependent and diffusion tensor imaging techniques. Methods: Twelve chronic stroke patients were recruited; inclusion criteria were stroke lasting 3 months to 1 year, motor strength of hand muscles of at least 2, and NIHSS of 4–15, and patients had to be conscious and able to comprehend. Fugl Meyer (FM, modified Barthel index (mBI, MRC, Ashworth tone grade scale scores and functional imaging scans were assessed at baseline, and after 8 and 24 weeks. Bone marrow was aspirated under aseptic conditions and expansion of MSC took 3 weeks with animal serum-free media (Stem Pro SFM. Six patients were administered a mean of 50–60 × 106 cells i.v. followed by 8 weeks of physiotherapy. Six patients served as controls. This was a non-randomized experimental controlled trial. Results: Clinical and radiological scanning was normal for the stem cell group patients. There was no mortality or cell-related adverse reaction. The laboratory tests on days 1, 3, 5 and 7 were also normal in the MSC group till the last follow-up. The FM and mBI showed a modest increase in the stem cell group compared to controls. There was an increased number of cluster activation of Brodmann areas BA 4 and BA 6 after stem cell infusion compared to controls, indicating neural plasticity. Conclusion: MSC therapy aiming to restore function in stroke is safe and feasible. Further randomized controlled trials are needed

  20. Improving the Post-Stroke Therapeutic Potency of Mesenchymal Multipotent Stromal Cells by Cocultivation With Cortical Neurons: The Role of Crosstalk Between Cells.

    Science.gov (United States)

    Babenko, Valentina A; Silachev, Denis N; Zorova, Ljubava D; Pevzner, Irina B; Khutornenko, Anastasia A; Plotnikov, Egor Y; Sukhikh, Gennady T; Zorov, Dmitry B

    2015-09-01

    The goal of the present study was to maximally alleviate the negative impact of stroke by increasing the therapeutic potency of injected mesenchymal multipotent stromal cells (MMSCs). To pursue this goal, the intercellular communications of MMSCs and neuronal cells were studied in vitro. As a result of cocultivation of MMSCs and rat cortical neurons, we proved the existence of intercellular contacts providing transfer of cellular contents from one cell to another. We present evidence of intercellular exchange with fluorescent probes specifically occupied by cytosol with preferential transfer from neurons toward MMSCs. In contrast, we observed a reversed transfer of mitochondria (from MMSCs to neural cells). Intravenous injection of MMSCs in a postischemic period alleviated the pathological indexes of a stroke, expressed as a lower infarct volume in the brain and partial restoration of neurological status. Also, MMSCs after cocultivation with neurons demonstrated more profound neuroprotective effects than did unprimed MMSCs. The production of the brain-derived neurotrophic factor was slightly increased in MMSCs, and the factor itself was redistributed in these cells after cocultivation. The level of Miro1 responsible for intercellular traffic of mitochondria was increased in MMSCs after cocultivation. We conclude that the exchange by cellular compartments between neural and stem cells improves MMSCs' protective abilities for better rehabilitation after stroke. This could be used as an approach to enhance the therapeutic benefits of stem cell therapy to the damaged brain. The idea of priming stem cells before practical use for clinical purposes was applied. Thus, cells were preconditioned by coculturing them with the targeted cells (i.e., neurons for the treatment of brain pathological features) before the transfusion of stem cells to the organism. Such priming improved the capacity of stem cells to treat stroke. Some additional minimal study will be required to

  1. The vectorized pinball contact impact routine

    International Nuclear Information System (INIS)

    Belytschko, T.B.; Neal, M.O.

    1989-01-01

    When simulating the impact-penetration of two bodies with explicit finite element methods, some type of interaction or contact algorithm must be included. These algorithms, often called slideline algorithms, must enforce the constraint that the two bodies cannot occupy the same space at the same time. Lagrange multiplier, penalty, and projection techniques have all been proposed to enforce this added constraint. For problems which include large relative motions between the two bodies and erosion of elements, it becomes difficult and time consuming to keep track of which elements of the bodies should be involved in the impact calculations. This computational expense is magnified by the fact that these slideline algorithms have many branches which are not amenable to vectorization. In dynamic finite element simulations with explicit time integration, many of the element and nodal calculations can be vectorized and the slideline calculations can require a considerable percentage of the total computation time. The thrust of the pinball algorithm discussed in this paper is to allow vectorization of as much of the slideline calculations as possible. This is accomplished by greatly simplifying both the search for the elements involved in the impact and in the enforcement of impenetrability with the use of spheres, or pinballs, for each element in the slideline calculations. In this way, the search requires a simple check on the distances between elements to determine if contact has been made. Once the contacting pairs of elements have been determined with a single global search of the two slidelines, the impenetrability condition is enforced with the use of a penalty type formulation which can be completely vectorized

  2. CONTACT LENS RELATED CORNEAL ULCER

    Directory of Open Access Journals (Sweden)

    AGARWAL P

    2010-01-01

    Full Text Available A corneal ulcer caused by infection is one of the major causes of blindness worldwide. One of the recent health concerns is the increasing incidence of corneal ulcers associated with contact lens user especially if the users fail to follow specific instruction in using their contact lenses. Risk factors associated with increased risk of contact lens related corneal ulcers are:overnight wear, long duration of continuous wear, lower socio-economic classes, smoking, dry eye and poor hygiene. The presenting symptoms of contact lens related corneal ulcers include eye discomfort, foreign body sensation and lacrimation. More serious symptoms are redness (especially circum-corneal injection, severe pain, photophobia, eye discharge and blurring of vision. The diagnosis is established by a thorough slit lamp microscopic examination with fluorescein staining and corneal scraping for Gram stain and culture of the infective organism. Delay in diagnosing and treatment can cause permanent blindness, therefore an early referral to ophthalmologist and commencing of antimicrobial therapy can prevent visual loss.

  3. Contact symmetries and Hamiltonian thermodynamics

    International Nuclear Information System (INIS)

    Bravetti, A.; Lopez-Monsalvo, C.S.; Nettel, F.

    2015-01-01

    It has been shown that contact geometry is the proper framework underlying classical thermodynamics and that thermodynamic fluctuations are captured by an additional metric structure related to Fisher’s Information Matrix. In this work we analyse several unaddressed aspects about the application of contact and metric geometry to thermodynamics. We consider here the Thermodynamic Phase Space and start by investigating the role of gauge transformations and Legendre symmetries for metric contact manifolds and their significance in thermodynamics. Then we present a novel mathematical characterization of first order phase transitions as equilibrium processes on the Thermodynamic Phase Space for which the Legendre symmetry is broken. Moreover, we use contact Hamiltonian dynamics to represent thermodynamic processes in a way that resembles the classical Hamiltonian formulation of conservative mechanics and we show that the relevant Hamiltonian coincides with the irreversible entropy production along thermodynamic processes. Therefore, we use such property to give a geometric definition of thermodynamically admissible fluctuations according to the Second Law of thermodynamics. Finally, we show that the length of a curve describing a thermodynamic process measures its entropy production

  4. An improved diagnostic contact lens.

    Science.gov (United States)

    Smith, R J

    1979-01-01

    Modification of a standard Goldmann goniolens by reducing the curvature of the contact surface to 8.5 mm radius of curvature (from the standard curvature of 7.4 mm) enabled gonioscopy to be carried out without the nuisance of air bubbles. Images PMID:465424

  5. Stellenbosch Papers in Linguistics: Contact

    African Journals Online (AJOL)

    Mailing Address. Editors SPiL. Department of General Linguistics University of Stellenbosch Private Bag X1 Matieland, 7602. Stellenbosch South Africa. Principal Contact. Dr Kate Huddlestone Journal Manager Department of General Linguistics. University of Stellenbosch. Private Bag X1. Matieland, 7602. Stellenbosch.

  6. Ohmic contacts to semiconducting diamond

    Science.gov (United States)

    Zeidler, James R.; Taylor, M. J.; Zeisse, Carl R.; Hewett, C. A.; Delahoussaye, Paul R.

    1990-10-01

    Work was carried out to improve the electron beam evaporation system in order to achieve better deposited films. The basic system is an ion pumped vacuum chamber, with a three-hearth, single-gun e-beam evaporator. Four improvements were made to the system. The system was thoroughly cleaned and new ion pump elements, an e-gun beam adjust unit, and a more accurate crystal monitor were installed. The system now has a base pressure of 3 X 10(exp -9) Torr, and can easily deposit high-melting-temperature metals such as Ta with an accurately controlled thickness. Improved shadow masks were also fabricated for better alignment and control of corner contacts for electrical transport measurements. Appendices include: A Thermally Activated Solid State Reaction Process for Fabricating Ohmic Contacts to Semiconducting Diamond; Tantalum Ohmic Contacts to Diamond by a Solid State Reaction Process; Metallization of Semiconducting Diamond: Mo, Mo/Au, and Mo/Ni/Au; Specific Contact Resistance Measurements of Ohmic Contracts to Diamond; and Electrical Activation of Boron Implanted into Diamond.

  7. Sandia National Laboratories: Contact Us

    Science.gov (United States)

    Employment (VOE) - New Mexico and California Please submit your requests by fax OR email - not both. Fax Number: (505) 845-0097, ATTN: HR Records Email Address: HR-Records@sandia.gov HR Records' Hotline: (505 in Writing Requester's Contact Information: Requester's name, company name (if applicable), phone

  8. Transcriptional regulation of epithelial-mesenchymal transition in melanoma

    International Nuclear Information System (INIS)

    Wels, C.

    2010-01-01

    The downregulation of epithelial markers followed by upregulation of mesenchymal characteristics is an important step in melanoma development. This process goes along with gains in cell proliferation and motility, depolarization and detachment from neighbouring cells, finally enabling melanoma cells to leave the primary site of tumor growth and to circulate through the blood or lymphatic system. The entirety of these events is referred to as epithelial-mesenchymal transition (EMT). Changes during EMT are accomplished by a set of transcription factors which share the same DNA binding site called E-box. These E-box binding transcription factors are subsumed as epithelial-mesenchymal transitions regulators (EMTRs). In this thesis, I studied the interplay of the zinc-finger transcription factors Slug and ZEB1 and the basic helix-loop-helix transcription factor Twist during melanoma progression. I demonstrate for the first time the direct and specific transcriptional upregulation of one EMTR, ZEB1, by another, Slug, using gene silencing and overexpression studies together with mobility shift and luciferase assays. The two transcription factors cooperate in repressing the epithelial adhesion molecule E-cadherin which is supposed to be a crucial step during early EMT. Further, they show additive effects in promoting detachment from neighbouring cells and cell migration. Conceptually, Slug and ZEB1 are supported by Twist, a transcription factor that might be less pivotal for E-cadherin repression but rather for inducing the expression of the mesenchymal marker N-cadherin, enabling adhesion to mesenchymal cells, thereby promoting migration and invasion of melanoma cells.Taken together, I provide a model of a hierarchical organization of EMT transcription factors, with Slug as a transcriptional activator of ZEB1, leading to cooperative effects on detachment and migration and, together with Twist, leading to EMT in melanoma. (author) [de

  9. The masonry behaviour under contact detonation

    Directory of Open Access Journals (Sweden)

    Marin Lupoae

    2017-03-01

    Full Text Available Breaching in masonry wall as a process of quick intervention of special forces in emergency cases, may require the use of explosive charges. In order to maximize the explosive effects on the wall and to minimize the shock wave and fragments propulsion, such breaching systems usually use a water layer which cover the explosive charge. The thickness of the water layer has a significant influence both on the mitigation of unwanted effects and enhancing the demolition effect, but also increases the mass of the system which can have negative consequences on the maneuverability and rapidity of intervention, respectivly. In this respect, the paper under consideration addresses numerical and experimental research on masonry walls to determine the behavior of mortar and brick under contact detonation and to establish an optimal water layer thickness to balance the breaching system requirement related to the mass on the one hand and effects and offered protection on the other hand.

  10. Influence of Mesenchymal Stem Cells Conditioned Media on Proliferation of Urinary Tract Cancer Cell Lines and Their Sensitivity to Ciprofloxacin.

    Science.gov (United States)

    Maj, Malgorzata; Bajek, Anna; Nalejska, Ewelina; Porowinska, Dorota; Kloskowski, Tomasz; Gackowska, Lidia; Drewa, Tomasz

    2017-06-01

    Mesenchymal stem cells (MSCs) are known to interact with cancer cells through direct cell-to-cell contact and secretion of paracrine factors, although their exact influence on tumor progression in vivo remains unclear. To better understand how fetal and adult stem cells affect tumors, we analyzed viability of human renal (786-0) and bladder (T24) carcinoma cell lines cultured in conditioned media harvested from amniotic fluid-derived stem cells (AFSCs) and adipose-derived stem cells (ASCs). Both media reduced metabolic activity of 786-0 cells, however, decreased viability of T24 cells was noted only after incubation with conditioned medium from ASCs. To test the hypothesis that MSCs-secreted factors might be involved in chemoresistance acquisition, we further analyzed influence of mesenchymal stem cell conditioned media (MSC-CM) on cancer cells sensitivity to ciprofloxacin, that is considered as potential candidate agent for urinary tract cancers treatment. Significantly increased resistance to tested drug indicates that MSCs may protect cancer cells from chemotherapy. J. Cell. Biochem. 118: 1361-1368, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Long noncoding RNAs related to the odontogenic potential of dental mesenchymal cells in mice.

    Science.gov (United States)

    Zheng, Yunfei; Jia, Lingfei

    2016-07-01

    The purpose of this study is to identify the lncRNAs that are associated with the odontogenic potential in mouse dental mesenchymal cells. The odontogenic potential of dental mesenchymal cells was found to be lost in the course of in vitro culture, so the lncRNA profiles were subsequently compared between freshly-isolated and cultured dental mesenchymal cells using RNA-sequencing. A co-expression analysis of differentially expressed lncRNAs and coding RNAs was performed to understand their potential functions. The expression of several selected lncRNAs was also examined in developing tooth germs. Compared with cultured dental mesenchymal cells, 108 lncRNAs were upregulated and 36 lncRNAs were downregulated in freshly-isolated dental mesenchymal cells. Coding genes correlated with the lncRNAs were mainly associated with DNA and protein metabolic processes and cytoskeletal anchorage. Meg3, Malat1, Xist, and Dlx1as were significantly downregulated in cultured dental mesenchymal cells but were upregulated in odontogenic dental mesenchymal tissues. Moreover, the levels of Dlx1as were negatively correlated with that of Dlx1 in dental mesenchymal cells and dental mesenchymal tissues. The lncRNA profiles of dental mesenchymal cells are significantly changed during culturing, and the dysregulation of lncRNAs is associated with the loss of odontogenic potential. Copyright © 2016. Published by Elsevier Ltd.

  12. Contact metallurgy optimization for ohmic contacts to InP

    DEFF Research Database (Denmark)

    Clausen, Thomas; Pedersen, Arne Skyggebjerg; Leistiko, Otto

    1991-01-01

    AuGeNi and AuZnNi metallizations to n- and p-InP were studied as a function of the annealing temperature in a Rapid Thermal Annealing (RTA) system. For n-InP (S:8×1018cm-3) a broad minimum existed from 385°C to 500°C, in which the specific contact resistance, rc, was about 10-7 ¿cm2. The lowe...

  13. Contact Lens-Related Eye Infections

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Contact Lens-Related Eye Infections Sections Contact Lens-Related Eye ... Six Steps to Avoid Contact Lens Infections Contact Lens-Related Eye Infections Leer en Español: Infecciones relacionadas ...

  14. Straylight Measurements in Contact Lens Wear

    NARCIS (Netherlands)

    van der Meulen, Ivanka J. E.; Engelbrecht, Leonore A.; van Vliet, Johannes M. J.; Lapid-Gortzak, Ruth; Nieuwendaal, Carla P.; Mourits, Maarten P.; Schlingemann, Reinier O.; van den Berg, Thomas J. T. P.

    2010-01-01

    Purpose: (1) To quantify the effect of contact lens wear on straylight in rigid and soft contact lens wearers and (2) to relate findings to morphological changes and subjective complaints. Methods: Straylight was measured using the Oculus C-Quant during contact lens wear and after contact lens

  15. Influence of interfacial layer on contact resistance

    NARCIS (Netherlands)

    Roy, D.; In 't Zand, M.A.A.; Delhounge, R.; Klootwijk, J.H.; Wolters, Robertus A.M.

    2008-01-01

    The contact resistance between two materials is dependent on the intrinsic properties of the materials in contact and the presence and properties of an interfacial layer at the contact. This article presents the difference in contact resistance measurements with and without the presence of a process

  16. Role of metal/silicon semiconductor contact engineering for enhanced output current in micro-sized microbial fuel cells

    KAUST Repository

    Mink, Justine E.; Rojas, Jhonathan Prieto; Rader, Kelly; Hussain, Muhammad Mustafa

    2013-01-01

    contact material study. We utilized the industry standard contact material, aluminum, as well as a metal, whose silicide has recently been recognized for its improved performance in smallest scale integration requirements, cobalt. Our study shows

  17. Stability analysis of rough surfaces in adhesive normal contact

    Science.gov (United States)

    Rey, Valentine; Bleyer, Jeremy

    2018-03-01

    This paper deals with adhesive frictionless normal contact between one elastic flat solid and one stiff solid with rough surface. After computation of the equilibrium solution of the energy minimization principle and respecting the contact constraints, we aim at studying the stability of this equilibrium solution. This study of stability implies solving an eigenvalue problem with inequality constraints. To achieve this goal, we propose a proximal algorithm which enables qualifying the solution as stable or unstable and that gives the instability modes. This method has a low computational cost since no linear system inversion is required and is also suitable for parallel implementation. Illustrations are given for the Hertzian contact and for rough contact.

  18. Contact resistance of ceramic interfaces between materials used for solid oxide fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Koch, S.

    2002-01-01

    The contact resistance can be divided into two main contributions. The small area of contact between ceramic components results in resistance due to current constriction. Resistive phases or potential barriers at the interface result in an interface contribution to the contact resistance, which may be smaller or larger than the constriction resistance. The contact resistance between pairs of three different materials were analysed (strontium doped lanthanum manganite, yttria stabilised zirconia and strontium and nickel doped lanthanum cobaltite), and the effects of temperature, atmosphere, polarisation and mechanical load on the contact resistance were investigated. The investigations revealed that the mechanical load of a ceramic contact has a high influence on the contact resistance, and generally power law dependence between the contact resistance and the mechanical load was found. The influence of the mechanical load on the contact resistance was ascribed to an area effect. The contact resistance of the investigated materials was dominated by current constriction at high temperatures. The measured contact resistance was comparable to the resistance calculated on basis of the contact areas found by optical and electron microscopy. At low temperatures, the interface contribution to the contact resistance was dominating. The cobaltite interface could be described by one potential barrier at the contact interface, whereas the manganite interfaces required several consecutive potential barriers to model the observed behaviour. The current-voltage behaviour of the YSZ contact interfaces was only weakly non-linear, and could be described by 22{+-}1 barriers in series. Contact interfaces with sinterable contact layers were also investigated, and the measured contact resistance for these interfaces were more than 10 times less than for the other interfaces. (au)

  19. PREFACE: Non-contact AFM Non-contact AFM

    Science.gov (United States)

    Giessibl, Franz J.; Morita, Seizo

    2012-02-01

    This special issue is focussed on high resolution non-contact atomic force microscopy (AFM). Non-contact atomic force microscopy was established approximately 15 years ago as a tool to image conducting and insulating surfaces with atomic resolution. Since 1998, an annual international conference has taken place, and although the proceedings of these conferences are a useful source of information, several key developments warrant devoting a special issue to this subject. In the theoretic field, the possibility of supplementing established techniques such as scanning tunneling microscopy (STM) and Kelvin probe microscopy with atomically resolved force micrsoscopy poses many challenges in the calculation of contrast and contrast reversal. The surface science of insulators, self-assembled monolayers and adsorbates on insulators is a fruitful field for the application of non-contact AFM: several articles in this issue are devoted to these subjects. Atomic imaging and manipulation have been pioneered using STM, but because AFM allows the measurement of forces, AFM has had a profound impact in this field as well. Three-dimensional force spectroscopy has allowed many important insights into surface science. In this issue a combined 3D tunneling and force microscopy is introduced. Non-contact AFM typically uses frequency modulation to measure force gradients and was initially used mainly in a vacuum. As can be seen in this issue, frequency modulation is now also used in ambient conditions, allowing better spatial and force resolution. We thank all of the contributors for their time and efforts in making this special issue possible. We are also very grateful to the staff of IOP Publishing for handling the administrative aspects and for steering the refereeing process. Non-contact AFM contents Relation between the chemical force and the tunnelling current in atomic point contacts: a simple model Pavel Jelínek, Martin Ondrácek and Fernando Flores Theoretical simulation of

  20. Contact allergy epidemics and their controls

    DEFF Research Database (Denmark)

    Thyssen, Jacob Pontoppidan; Johansen, Jeanne Duus; Menné, Torkil

    2007-01-01

    Contact dermatitis can be severe and lead to sick leave as well as significant healthcare expenses. The aim of this review is to present the published knowledge on 6 historical epidemics of contact allergy to apply this knowledge on the prevention and control of future contact allergy epidemics. ...... to prevent contact allergy epidemics. It is essential that dermatologist, scientists, administrators, and consumers organize and structure known methods to accelerate the control of emerging contact allergens....