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Sample records for spontaneous transitional cell

  1. Mesenchymal to Epithelial Transition Mediated by CDH1 Promotes Spontaneous Reprogramming of Male Germline Stem Cells to Pluripotency.

    Science.gov (United States)

    An, Junhui; Zheng, Yu; Dann, Christina Tenenhaus

    2017-02-14

    Cultured spermatogonial stem cells (GSCs) can spontaneously form pluripotent cells in certain culture conditions. However, GSC reprogramming is a rare event that is largely unexplained. We show GSCs have high expression of mesenchymal to epithelial transition (MET) suppressors resulting in a developmental barrier inhibiting GSC reprogramming. Either increasing OCT4 or repressing transforming growth factor β (TGF-β) signaling promotes GSC reprogramming by upregulating CDH1 and boosting MET. Reducing ZEB1 also enhances GSC reprogramming through its direct effect on CDH1. RNA sequencing shows that rare GSCs, identified as CDH1 + after trypsin digestion, are epithelial-like cells. CDH1 + GSCs exhibit enhanced reprogramming and become more prevalent during the course of reprogramming. Our results provide a mechanistic explanation for the spontaneous emergence of pluripotent cells from GSC cultures; namely, rare GSCs upregulate CDH1 and initiate MET, processes normally kept in check by ZEB1 and TGF-β signaling, thereby ensuring germ cells are protected from aberrant acquisition of pluripotency. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Mesenchymal to Epithelial Transition Mediated by CDH1 Promotes Spontaneous Reprogramming of Male Germline Stem Cells to Pluripotency

    Directory of Open Access Journals (Sweden)

    Junhui An

    2017-02-01

    Full Text Available Cultured spermatogonial stem cells (GSCs can spontaneously form pluripotent cells in certain culture conditions. However, GSC reprogramming is a rare event that is largely unexplained. We show GSCs have high expression of mesenchymal to epithelial transition (MET suppressors resulting in a developmental barrier inhibiting GSC reprogramming. Either increasing OCT4 or repressing transforming growth factor β (TGF-β signaling promotes GSC reprogramming by upregulating CDH1 and boosting MET. Reducing ZEB1 also enhances GSC reprogramming through its direct effect on CDH1. RNA sequencing shows that rare GSCs, identified as CDH1+ after trypsin digestion, are epithelial-like cells. CDH1+ GSCs exhibit enhanced reprogramming and become more prevalent during the course of reprogramming. Our results provide a mechanistic explanation for the spontaneous emergence of pluripotent cells from GSC cultures; namely, rare GSCs upregulate CDH1 and initiate MET, processes normally kept in check by ZEB1 and TGF-β signaling, thereby ensuring germ cells are protected from aberrant acquisition of pluripotency.

  3. Spontaneous regression of metastatic Merkel cell carcinoma.

    LENUS (Irish Health Repository)

    Hassan, S J

    2010-01-01

    Merkel cell carcinoma is a rare aggressive neuroendocrine carcinoma of the skin predominantly affecting elderly Caucasians. It has a high rate of local recurrence and regional lymph node metastases. It is associated with a poor prognosis. Complete spontaneous regression of Merkel cell carcinoma has been reported but is a poorly understood phenomenon. Here we present a case of complete spontaneous regression of metastatic Merkel cell carcinoma demonstrating a markedly different pattern of events from those previously published.

  4. Spontaneous Formation of Tumorigenic Hybrids between Breast Cancer and Multipotent Stromal Cells Is a Source of Tumor Heterogeneity

    OpenAIRE

    Rappa, Germana; Mercapide, Javier; Lorico, Aurelio

    2012-01-01

    Breast cancer progression involves cancer cell heterogeneity, with generation of invasive/metastatic breast cancer cells within populations of nonmetastatic cells of the primary tumor. Sequential genetic mutations, epithelial-to-mesenchymal transition, interaction with local stroma, and formation of hybrids between cancer cells and normal bone marrow–derived cells have been advocated as tumor progression mechanisms. We report herein the spontaneous in vitro formation of heterotypic hybrids be...

  5. Merkel Cell Carcinoma with Spontaneous Regression: A Case Report and Immunohistochemical Study

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    Hitoshi Terui

    2016-02-01

    Full Text Available Merkel cell carcinoma (MCC is an aggressive neuroendocrine carcinoma that only rarely regresses spontaneously. Since little is known about the immunological mechanisms involved in the spontaneous regression of MCC, we describe a case of MCC with spontaneous regression and employed immunohistochemical staining for cytotoxic and immunosuppressive molecules to investigate possible mechanisms involved in the spontaneous regression of MCC. Interestingly, compared to conventional MCC, tumor-infiltrating lymphocytes in MCC with spontaneous regression contained higher numbers of CD8+ cells and granulysin-bearing cells and lower numbers of CD206+ cells. Our present study suggests one of the possible reasons for the spontaneous regression of MCC.

  6. Epigenetic dysregulation in mesenchymal stem cell aging and spontaneous differentiation.

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    Zhilong Li

    Full Text Available BACKGROUND: Mesenchymal stem cells (MSCs hold great promise for the treatment of difficult diseases. As MSCs represent a rare cell population, ex vivo expansion of MSCs is indispensable to obtain sufficient amounts of cells for therapies and tissue engineering. However, spontaneous differentiation and aging of MSCs occur during expansion and the molecular mechanisms involved have been poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: Human MSCs in early and late passages were examined for their expression of genes involved in osteogenesis to determine their spontaneous differentiation towards osteoblasts in vitro, and of genes involved in self-renewal and proliferation for multipotent differentiation potential. In parallel, promoter DNA methylation and hostone H3 acetylation levels were determined. We found that MSCs underwent aging and spontaneous osteogenic differentiation upon regular culture expansion, with progressive downregulation of TERT and upregulation of osteogenic genes such as Runx2 and ALP. Meanwhile, the expression of genes associated with stem cell self-renewal such as Oct4 and Sox2 declined markedly. Notably, the altered expression of these genes were closely associated with epigenetic dysregulation of histone H3 acetylation in K9 and K14, but not with methylation of CpG islands in the promoter regions of most of these genes. bFGF promoted MSC proliferation and suppressed its spontaneous osteogenic differentiation, with corresponding changes in histone H3 acetylation in TERT, Oct4, Sox2, Runx2 and ALP genes. CONCLUSIONS/SIGNIFICANCE: Our results indicate that histone H3 acetylation, which can be modulated by extrinsic signals, plays a key role in regulating MSC aging and differentiation.

  7. Large social disparities in spontaneous preterm birth rates in transitional Russia.

    Science.gov (United States)

    Grjibovski, A M; Bygren, L O; Yngve, A; Sjöström, M

    2005-02-01

    This study estimated the effect of maternal sociodemographic, obstetric and lifestyle factors on the risk of spontaneous preterm birth in a Russian town. All women with singleton pregnancies registered at prenatal care centres in Severodvinsk in 1999 comprised the cohort for this study (n=1559). Analysis was based on spontaneous live singleton births at the maternity home (n=1103). Multivariable logistic regression was applied to quantify the effect of the studied factors on the risk of preterm birth. Differences in gestation duration were studied using multiple linear regression. In total, 5.6% of all spontaneous births were preterm. Increased risks of preterm delivery were found in women with lower levels of education and in students. Placental complications, stress and a history of fetal death in previous pregnancies were also associated with elevated risks for preterm delivery. Smoking, hypertension and multigravidity were associated with reduced length of pregnancy in metric form. In addition to medical risk factors, social factors are important determinants of preterm birth in transitional Russia. Large disparities in preterm birth rates may reflect the level of inequalities in transitional Russia. Social variations in pregnancy outcomes should be monitored.

  8. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus Preliminary Evaluation Results

    Science.gov (United States)

    2008-10-16

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The report discusses the planned fuel cell bus demonstration and equipment us...

  9. [Decidual natural killer cells in recurrent spontaneous abortions].

    Science.gov (United States)

    Janosević, Dragana Radović; Lilić, Vekoslav; Basić, Hakija; Pavlović, Aleksandra Tubić; Stefanović, Milan; Milosević, Jelena

    2011-01-01

    A repeated or habitual miscarriage (PSP) is defined as three or more consecutive losses of pregnancy. In the first three months of pregnancy, habitual miscarriages occur in about 1% of pregnant women, out of which 50% are of an unknown etiology. It is believed that among them, the greatest number is the consequence of an inadequate alloimmune response of a women to the pregnancy. The endocrine and immune systems are in a close interaction during the implantation and maintaining of pregnancy. This communication is the most obvious on endometrium of pregnancy decidua. The aim of the study was to identify the number and the subpopulation distribution of the decidual NK cells in the decidua by using an immunohistochemical method. The research included a group of 30 women who had had two spontaneous miscarriages consecutively in the first three months of their pregnancy, while the curettage after the third spontaneous abortion was histopathologically and immunohistochemically analyzed. The control group consisted of 20 women without a problematic reproductive anamnesis, who had had their pregnancy terminated for social reasons. The criteria for the eliminating from the research were the diagnosed uterus anomalies, positive screening on thrombophilia, as well as women suffering from diabetes melitus and the ones with the thyroid gland function disorder. The number and the phenotype structure of the uterus NK cells were significantly different between the decidua of a normal pregnancy and that in PSP. In the decidua in PSP, there were much more NK cells with the phenotype of the peripheral circulation CD57 and CD56dim, while in the decidua of the control group the dominant cells were the typical uNK cell subpopulation CD56bright. The above mentioned results show that the disregulation of the immunocompetent cells of the decidua, by creating an inadequate cytokine milieu, is one of the mechanism of rejecting the semiallogeneic blastocyst.

  10. Decidual natural killer cells in recurrent spontaneous abortions

    Directory of Open Access Journals (Sweden)

    Radović-Janošević Dragana

    2011-01-01

    Full Text Available Background/Aim. A repeated or habitual miscarriage (PSP is defined as three or more consecutive losses of pregnancy. In the first three months of pregnancy, habitual miscarriages occur in about 1% of pregnant women, out of which 50% are of an unknown etiology. It is believed that among them, the greatest number is the consequence of an inadequate alloimmune response of a women to the pregnancy. The endocrine and immune systems are in a close interaction during the implantation and maintaining of pregnancy. This communication is the most obvious on endometrium of pregnancy decidua. The aim of the study was to identify the number and the subpopulation distribution of the decidual NK cells in the decidua by using an immunohistochemical method. Methods. The research included a group of 30 women who had had two spontaneous miscarriages consecutively in the first three months of their pregnancy, while the curettage after the third spontaneous abortion was histopathologically and immunohistochemically analyzed. The control group consisted of 20 women without a problematic reproductive anamnesis, who had had their pregnancy terminated for social reasons. The criteria for the eliminating from the research were the diagnosed uterus anomalies, positive screening on thrombophilia, as well as women suffering from diabetes melitus and the ones with the thyroid gland function disorder. Results. The number and the phenotype structure of the uterus NK cells were significantly different between the decidua of a normal pregnancy and that in PSP. In the decidua in PSP, there were much more NK cells with the phenotype of the peripheral circulation CD57 and CD56dim, while in the decidua of the control group the dominant cells were the typical uNK cell subpopulation CD56bright. Conclusion. The above mentioned results show that the disregulation of the immunocompetent cells of the decidua, by creating an inadequate cytokine milieu, is one of the mechanism of rejecting

  11. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2007-03-01

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  12. The rate of spontaneous mutations in human myeloid cells

    International Nuclear Information System (INIS)

    Araten, David J.; Krejci, Ondrej; DiTata, Kimberly; Wunderlich, Mark; Sanders, Katie J.; Zamechek, Leah; Mulloy, James C.

    2013-01-01

    Highlights: • We provide the first measurement of the mutation rate (μ) in human myeloid cells. • μ is measured to be 3.6–23 × 10 −7 per cell division. • The AML-ETO and MLL-AF9 fusions do not seem to increase μ. • Cooperating mutations in NRAS, FLT3 and p53 not seem to increase μ. • Hypermutability may be required to explain leukemogenesis. - Abstract: The mutation rate (μ) is likely to be a key parameter in leukemogenesis, but historically, it has been difficult to measure in humans. The PIG-A gene has some advantages for the detection of spontaneous mutations because it is X-linked, and therefore only one mutation is required to disrupt its function. Furthermore, the PIG-A-null phenotype is readily detected by flow cytometry. Using PIG-A, we have now provided the first in vitro measurement of μ in myeloid cells, using cultures of CD34+ cells that are transduced with either the AML-ETO or the MLL-AF9 fusion genes and expanded with cytokines. For the AML-ETO cultures, the median μ value was ∼9.4 × 10 −7 (range ∼3.6–23 × 10 −7 ) per cell division. In contrast, few spontaneous mutations were observed in the MLL-AF9 cultures. Knockdown of p53 or introduction of mutant NRAS or FLT3 alleles did not have much of an effect on μ. Based on these data, we provide a model to predict whether hypermutability must occur in the process of leukemogenesis

  13. Spontaneous malignant transformation of conventional giant cell tumor

    Energy Technology Data Exchange (ETDEWEB)

    Grote, H.J.; Pomjanski, N.; Boecking, A. [Institute of Cytopathology, Heinrich Heine University, Moorenstrasse 5, 40225, Duesseldorf (Germany); Braun, M. [Orthopedic Hospital Volmarstein, University of Witten/Herdecke, Hartmannstrasse 24, 58300, Wetter (Ruhr) (Germany); Kalinski, T.; Roessner, A. [Department of Pathology, Otto von Guericke University, Leipziger Strasse 44, 39120, Magdeburg (Germany); Back, W.; Bleyl, U. [Department of Pathology, Ruprecht Karls University Heidelberg, University Hospital Mannheim, Theodor-Kutzer-Ufer, 68167, Mannheim (Germany)

    2004-03-01

    Spontaneous malignant transformation of conventional giant cell tumor (GCT) of bone is exceedingly rare. We report on a case of GCT of the iliac crest in a 35-year-old woman with malignant change into a high-grade osteosarcoma 10 years after the first appearance of GCT on a radiograph. Since the patient refused therapy for personal reasons the tumor remained untreated until sarcomatous transformation occurred. Image cytometry showed DNA aneuploidy and a suspiciously high 2c deviation index (2cDI) in the primary bone lesion. A thorough review of the world literature revealed only seven fully documented cases of secondary malignant GCT which matched the definition of a ''sarcomatous growth that occurs at the site of a previously documented benign giant cell tumor'' and not treated by radiotherapy. These cases as well as the current one suggest that a spontaneous secondary malignant GCT presents as a frankly sarcomatous tumor in the form of an osteosarcoma or malignant fibrous histiocytoma. It usually appears at sites of typical GCTs - often without any recurrent intermediate state - and is diagnosed 3 or more years after the primary bone lesion. The prognosis is poor. (orig.)

  14. Study of ion viscosity by spontaneous L-H transitions under marginal hot cathode biasing in the Tohoku University Heliac

    International Nuclear Information System (INIS)

    Kitajima, S.; Takahashi, H.; Tanaka, Y.; Utoh, H.; Takenaga, M.; Yokoyama, M.; Inagaki, S.; Suzuki, Y.; Nishimura, K.; Ogawa, H.; Takayama, M.; Shinde, J.; Ogawa, M.; Aoyama, H.; Iwazaki, K.; Okamoto, A.; Shinto, K.; Sasao, M.

    2008-01-01

    Using the spontaneous transition condition under marginal hot cathode biasing, the ion viscosity at the L-H transition was estimated in various magnetic configurations in the Tohoku University Heliac. The critical viscosity, which is the viscosity at the transition point, was experimentally estimated from the J x B driving force. The critical viscosities in different magnetic configurations were in agreement with the neoclassical predictions within a factor of 2 and were compared with the viscosities obtained in the externally forced biasing experiments. Although the transition points were spread over a wide range, poloidal Mach numbers at the transition point were concentrated near the viscosity maxima predicted by the theory

  15. Ordered patterns of cell shape and orientational correlation during spontaneous cell migration.

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    Yusuke T Maeda

    Full Text Available BACKGROUND: In the absence of stimuli, most motile eukaryotic cells move by spontaneously coordinating cell deformation with cell movement in the absence of stimuli. Yet little is known about how cells change their own shape and how cells coordinate the deformation and movement. Here, we investigated the mechanism of spontaneous cell migration by using computational analyses. METHODOLOGY: We observed spontaneously migrating Dictyostelium cells in both a vegetative state (round cell shape and slow motion and starved one (elongated cell shape and fast motion. We then extracted regular patterns of morphological dynamics and the pattern-dependent systematic coordination with filamentous actin (F-actin and cell movement by statistical dynamic analyses. CONCLUSIONS/SIGNIFICANCE: We found that Dictyostelium cells in both vegetative and starved states commonly organize their own shape into three ordered patterns, elongation, rotation, and oscillation, in the absence of external stimuli. Further, cells inactivated for PI3-kinase (PI3K and/or PTEN did not show ordered patterns due to the lack of spatial control in pseudopodial formation in both the vegetative and starved states. We also found that spontaneous polarization was achieved in starved cells by asymmetric localization of PTEN and F-actin. This breaking of the symmetry of protein localization maintained the leading edge and considerably enhanced the persistence of directed migration, and overall random exploration was ensured by switching among the different ordered patterns. Our findings suggest that Dictyostelium cells spontaneously create the ordered patterns of cell shape mediated by PI3K/PTEN/F-actin and control the direction of cell movement by coordination with these patterns even in the absence of external stimuli.

  16. Synchrotron Diffraction Studies of Spontaneous Magnetostriction in Rare Earth Transition Metal Compounds

    International Nuclear Information System (INIS)

    Ning Yang

    2004-01-01

    Thermal expansion anomalies of R 2 Fe 14 B and R 2 Fe 17 C x (x = 0,2) (R Y, Nd, Gd, Tb, Er) stoichiometric compounds are studied with high-energy synchrotron X-ray powder diffraction using Debye-Schemer geometry in temperature range 10K to 1000K. Large spontaneous magnetostriction up to their Curie temperatures (T c ) is observed. The a-axes show relatively larger invar effects than c-axes in the R 2 Fe 14 B compounds whereas the R 2 Fe 17 C x show the contrary anisotropies. The iron sub-lattice is shown to dominate the spontaneous magnetostriction of the compounds. The contribution of the rare earth sublattice is roughly proportional to the spin magnetic moment of the rare earth in the R 2 Fe 14 B compounds but in R 2 Fe 17 C x , the rare earth sub-lattice contribution appears more likely to be dominated by the local bonding. The calculation of spontaneous magnetostrain of bonds shows that the bonds associated with Fe(j2) sites in R 2 Fe 14 B and the dumbbell sites in R 2 Fe 17 C x have larger values, which is strongly related to their largest magnetic moment and Wigner-Seitz atomic cell volume. The roles of the carbon atoms in increasing the Curie temperatures of the R 2 Fe 17 compounds are attributed to the increased separation of Fe hexagons. The R 2 Fe 17 and R 2 Fe 14 B phases with magnetic rare earth ions also show anisotropies of thermal expansion above T c . For R 2 Fe 17 and R 2 Fe 14 B the a a /a c > 1 whereas the anisotropy is reversed with the interstitial carbon in R 2 Fe 17 . The average bond magnetostrain is shown to be a possible predictor of the magnetic moment of Fe sites in the compounds. Both of the theoretical and phenomenological models on spontaneous magnetostriction are discussed and a Landau model on the spontaneous magnetostriction is proposed

  17. Canine spontaneous head and neck squamous cell carcinomas represent their human counterparts at the molecular level.

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    Deli Liu

    2015-06-01

    Full Text Available Spontaneous canine head and neck squamous cell carcinoma (HNSCC represents an excellent model of human HNSCC but is greatly understudied. To better understand and utilize this valuable resource, we performed a pilot study that represents its first genome-wide characterization by investigating 12 canine HNSCC cases, of which 9 are oral, via high density array comparative genomic hybridization and RNA-seq. The analyses reveal that these canine cancers recapitulate many molecular features of human HNSCC. These include analogous genomic copy number abnormality landscapes and sequence mutation patterns, recurrent alteration of known HNSCC genes and pathways (e.g., cell cycle, PI3K/AKT signaling, and comparably extensive heterogeneity. Amplification or overexpression of protein kinase genes, matrix metalloproteinase genes, and epithelial-mesenchymal transition genes TWIST1 and SNAI1 are also prominent in these canine tumors. This pilot study, along with a rapidly growing body of literature on canine cancer, reemphasizes the potential value of spontaneous canine cancers in HNSCC basic and translational research.

  18. Cell Imaging by Spontaneous and Amplified Raman Spectroscopies

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    Giulia Rusciano

    2017-01-01

    Full Text Available Raman spectroscopy (RS is a powerful, noninvasive optical technique able to detect vibrational modes of chemical bonds. The high chemical specificity due to its fingerprinting character and the minimal requests for sample preparation have rendered it nowadays very popular in the analysis of biosystems for diagnostic purposes. In this paper, we first discuss the main advantages of spontaneous RS by describing the study of a single protozoan (Acanthamoeba, which plays an important role in a severe ophthalmological disease (Acanthamoeba keratitis. Later on, we point out that the weak signals that originated from Raman scattering do not allow probing optically thin samples, such as cellular membrane. Experimental approaches able to overcome this drawback are based on the use of metallic nanostructures, which lead to a huge amplification of the Raman yields thanks to the excitation of localized surface plasmon resonances. Surface-enhanced Raman scattering (SERS and tip-enhanced Raman scattering (TERS are examples of such innovative techniques, in which metallic nanostructures are assembled on a flat surface or on the tip of a scanning probe microscope, respectively. Herein, we provide a couple of examples (red blood cells and bacterial spores aimed at studying cell membranes with these techniques.

  19. Synchrotron Diffraction Studies of Spontaneous Magnetostriction in Rare Earth Transition Metal Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ning [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    Thermal expansion anomalies of R2Fe14B and R2Fe17Cx (x = 0,2) (R = Y, Nd, Gd, Tb, Er) stoichiometric compounds are studied with high-energy synchrotron X-ray powder diffraction using Debye-Schemer geometry in temperature range 10K to 1000K. Large spontaneous magnetostriction up to their Curie temperatures (Tc) is observed. The a-axes show relatively larger invar effects than c-axes in the R2Fe14B compounds whereas the R2Fe17Cx show the contrary anisotropies. The iron sub-lattice is shown to dominate the spontaneous magnetostriction of the compounds. The contribution of the rare earth sublattice is roughly proportional to the spin magnetic moment of the rare earth in the R2Fe14B compounds but in R2Fe17Cx, the rare earth sub-lattice contribution appears more likely to be dominated by the local bonding. The calculation of spontaneous magnetostrain of bonds shows that the bonds associated with Fe(j2) sites in R2Fe14B and the dumbbell sites in R2Fe17Cx have larger values, which is strongly related to their largest magnetic moment and Wigner-Seitz atomic cell volume. The roles of the carbon atoms in increasing the Curie temperatures of the R2Fe17 compounds are attributed to the increased separation of Fe hexagons. The R2Fe17 and R2Fe14B phases with magnetic rare earth ions also show anisotropies of thermal expansion above c. For R2Fe17 and R2Fe14B the a a/a c > 1 whereas the anisotropy is reversed with the interstitial carbon in R2Fe17. The average bond magnetostrain is shown to be a possible predictor of the magnetic moment of Fe sites in the compounds. Both of the theoretical and

  20. Factors affecting the spontaneous mutational spectra in somatic mammalian cells

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    О.А. Ковальова

    2006-04-01

    Full Text Available  In our survey of references we are discussed the influence of factors biological origin on the spontaneous mutation specters in mammalian. Seasonal and age components influence on the frequence of cytogenetic anomalies. The immune and endocrinous systems are take part in control of the alteration of the spontaneous mutation specters. Genetical difference of sensibility in animal and human at the alteration of factors enviroment as and  genetical differences of repair systems activity are may influence on individual variation of spontaneous destabilization characters of chromosomal apparatus.

  1. Spontaneous transformation of adult mesenchymal stem cells from cynomolgus macaques in vitro

    International Nuclear Information System (INIS)

    Ren, Zhenhua; Wang, Jiayin; Zhu, Wanwan; Guan, Yunqian; Zou, Chunlin; Chen, Zhiguo; Zhang, Y. Alex

    2011-01-01

    Mesenchymal stem cells (MSCs) have shown potential clinical utility in cell therapy and tissue engineering, due to their ability to proliferate as well as to differentiate into multiple lineages, including osteogenic, adipogenic, and chondrogenic specifications. Therefore, it is crucial to assess the safety of MSCs while extensive expansion ex vivo is a prerequisite to obtain the cell numbers for cell transplantation. Here we show that MSCs derived from adult cynomolgus monkey can undergo spontaneous transformation following in vitro culture. In comparison with MSCs, the spontaneously transformed mesenchymal cells (TMCs) display significantly different growth pattern and morphology, reminiscent of the characteristics of tumor cells. Importantly, TMCs are highly tumorigenic, causing subcutaneous tumors when injected into NOD/SCID mice. Moreover, no multiple differentiation potential of TMCs is observed in vitro or in vivo, suggesting that spontaneously transformed adult stem cells may not necessarily turn into cancer stem cells. These data indicate a direct transformation of cynomolgus monkey MSCs into tumor cells following long-term expansion in vitro. The spontaneous transformation of the cultured cynomolgus monkey MSCs may have important implications for ongoing clinical trials and for models of oncogenesis, thus warranting a more strict assessment of MSCs prior to cell therapy. -- Highlights: ► Spontaneous transformation of cynomolgus monkey MSCs in vitro. ► Transformed mesenchymal cells lack multipotency. ► Transformed mesenchymal cells are highly tumorigenic. ► Transformed mesenchymal cells do not have the characteristics of cancer stem cells.

  2. Spontaneous transformation of adult mesenchymal stem cells from cynomolgus macaques in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhenhua [Cell Therapy Center, Xuanwu Hospital, Capital Medical University, Beijing (China); Key Laboratory of Neurodegeneration, Ministry of Education, Beijing (China); Department of Anatomy, Anhui Medical University, Hefei, 230032 (China); Wang, Jiayin; Zhu, Wanwan; Guan, Yunqian; Zou, Chunlin [Cell Therapy Center, Xuanwu Hospital, Capital Medical University, Beijing (China); Key Laboratory of Neurodegeneration, Ministry of Education, Beijing (China); Chen, Zhiguo, E-mail: chenzhiguo@gmail.com [Cell Therapy Center, Xuanwu Hospital, Capital Medical University, Beijing (China); Key Laboratory of Neurodegeneration, Ministry of Education, Beijing (China); Stanford Institute for Stem Cell Biology and Regenerative Medicine and Department of Neurosurgery, Stanford, CA (United States); Zhang, Y. Alex, E-mail: yaz@bjsap.org [Cell Therapy Center, Xuanwu Hospital, Capital Medical University, Beijing (China); Key Laboratory of Neurodegeneration, Ministry of Education, Beijing (China)

    2011-12-10

    Mesenchymal stem cells (MSCs) have shown potential clinical utility in cell therapy and tissue engineering, due to their ability to proliferate as well as to differentiate into multiple lineages, including osteogenic, adipogenic, and chondrogenic specifications. Therefore, it is crucial to assess the safety of MSCs while extensive expansion ex vivo is a prerequisite to obtain the cell numbers for cell transplantation. Here we show that MSCs derived from adult cynomolgus monkey can undergo spontaneous transformation following in vitro culture. In comparison with MSCs, the spontaneously transformed mesenchymal cells (TMCs) display significantly different growth pattern and morphology, reminiscent of the characteristics of tumor cells. Importantly, TMCs are highly tumorigenic, causing subcutaneous tumors when injected into NOD/SCID mice. Moreover, no multiple differentiation potential of TMCs is observed in vitro or in vivo, suggesting that spontaneously transformed adult stem cells may not necessarily turn into cancer stem cells. These data indicate a direct transformation of cynomolgus monkey MSCs into tumor cells following long-term expansion in vitro. The spontaneous transformation of the cultured cynomolgus monkey MSCs may have important implications for ongoing clinical trials and for models of oncogenesis, thus warranting a more strict assessment of MSCs prior to cell therapy. -- Highlights: Black-Right-Pointing-Pointer Spontaneous transformation of cynomolgus monkey MSCs in vitro. Black-Right-Pointing-Pointer Transformed mesenchymal cells lack multipotency. Black-Right-Pointing-Pointer Transformed mesenchymal cells are highly tumorigenic. Black-Right-Pointing-Pointer Transformed mesenchymal cells do not have the characteristics of cancer stem cells.

  3. Noise-induced effects on multicellular biopacemaker spontaneous activity: Differences between weak and strong pacemaker cells

    Science.gov (United States)

    Aghighi, Alireza; Comtois, Philippe

    2017-09-01

    Self-organization of spontaneous activity of a network of active elements is important to the general theory of reaction-diffusion systems as well as for pacemaking activity to initiate beating of the heart. Monolayer cultures of neonatal rat ventricular myocytes, consisting of resting and pacemaker cells, exhibit spontaneous activation of their electrical activity. Similarly, one proposed approach to the development of biopacemakers as an alternative to electronic pacemakers for cardiac therapy is based on heterogeneous cardiac cells with resting and spontaneously beating phenotypes. However, the combined effect of pacemaker characteristics, density, and spatial distribution of the pacemaker cells on spontaneous activity is unknown. Using a simple stochastic pattern formation algorithm, we previously showed a clear nonlinear dependency of spontaneous activity (occurrence and amplitude of spontaneous period) on the spatial patterns of pacemaker cells. In this study, we show that this behavior is dependent on the pacemaker cell characteristics, with weaker pacemaker cells requiring higher density and larger clusters to sustain multicellular activity. These multicellular structures also demonstrated an increased sensitivity to voltage noise that favored spontaneous activity at lower density while increasing temporal variation in the period of activity. This information will help researchers overcome the current limitations of biopacemakers.

  4. Light-front quantized field theory (an introduction): spontaneous symmetry breaking. Phase transition in φ4 theory

    International Nuclear Information System (INIS)

    Srivastava, Prem P.

    1994-01-01

    The Dirac procedure is used to construct the Hamiltonian formulation of the scalar field theory on the light-front. The theory is quantized and the mechanism of the spontaneous symmetry breaking in the front form and the instant form dynamics are compared. The phase transition in (φ 4 )2 theory is also discussed and found to be of the second order. (author). 36 refs

  5. Human embryonic stem cell-derived neuronal cells form spontaneously active neuronal networks in vitro.

    Science.gov (United States)

    Heikkilä, Teemu J; Ylä-Outinen, Laura; Tanskanen, Jarno M A; Lappalainen, Riikka S; Skottman, Heli; Suuronen, Riitta; Mikkonen, Jarno E; Hyttinen, Jari A K; Narkilahti, Susanna

    2009-07-01

    The production of functional human embryonic stem cell (hESC)-derived neuronal cells is critical for the application of hESCs in treating neurodegenerative disorders. To study the potential functionality of hESC-derived neurons, we cultured and monitored the development of hESC-derived neuronal networks on microelectrode arrays. Immunocytochemical studies revealed that these networks were positive for the neuronal marker proteins beta-tubulin(III) and microtubule-associated protein 2 (MAP-2). The hESC-derived neuronal networks were spontaneously active and exhibited a multitude of electrical impulse firing patterns. Synchronous bursts of electrical activity similar to those reported for hippocampal neurons and rodent embryonic stem cell-derived neuronal networks were recorded from the differentiated cultures until up to 4 months. The dependence of the observed neuronal network activity on sodium ion channels was examined using tetrodotoxin (TTX). Antagonists for the glutamate receptors NMDA [D(-)-2-amino-5-phosphonopentanoic acid] and AMPA/kainate [6-cyano-7-nitroquinoxaline-2,3-dione], and for GABAA receptors [(-)-bicuculline methiodide] modulated the spontaneous electrical activity, indicating that pharmacologically susceptible neuronal networks with functional synapses had been generated. The findings indicate that hESC-derived neuronal cells can generate spontaneously active networks with synchronous communication in vitro, and are therefore suitable for use in developmental and drug screening studies, as well as for regenerative medicine.

  6. Visualizing cell state transition using Raman spectroscopy.

    Directory of Open Access Journals (Sweden)

    Taro Ichimura

    Full Text Available System level understanding of the cell requires detailed description of the cell state, which is often characterized by the expression levels of proteins. However, understanding the cell state requires comprehensive information of the cell, which is usually obtained from a large number of cells and their disruption. In this study, we used Raman spectroscopy, which can report changes in the cell state without introducing any label, as a non-invasive method with single cell capability. Significant differences in Raman spectra were observed at the levels of both the cytosol and nucleus in different cell-lines from mouse, indicating that Raman spectra reflect differences in the cell state. Difference in cell state was observed before and after the induction of differentiation in neuroblastoma and adipocytes, showing that Raman spectra can detect subtle changes in the cell state. Cell state transitions during embryonic stem cell (ESC differentiation were visualized when Raman spectroscopy was coupled with principal component analysis (PCA, which showed gradual transition in the cell states during differentiation. Detailed analysis showed that the diversity between cells are large in undifferentiated ESC and in mesenchymal stem cells compared with terminally differentiated cells, implying that the cell state in stem cells stochastically fluctuates during the self-renewal process. The present study strongly indicates that Raman spectral morphology, in combination with PCA, can be used to establish cells' fingerprints, which can be useful for distinguishing and identifying different cellular states.

  7. Determination of Autophagy in the Caco-2 Spontaneously Differentiating Model of Intestinal Epithelial Cells.

    Science.gov (United States)

    Tunçer, Sinem; Banerjee, Sreeparna

    2017-08-27

    The Caco-2 colorectal cancer cell line is widely used as a model for intestinal differentiation and barrier function. These cells, upon reaching confluency, spontaneously differentiate into enterocyte-like cells, synthesize intestinal enzymes, and form domes. Caco-2 cells also undergo autophagy in the course of differentiation. The criteria to establish the induction of autophagy in cells are already well established. Here, we describe the protocol for the spontaneous differentiation of Caco-2 cells and the detection of autophagy using Western blot, flow cytometry, and immunofluorescence.

  8. Computed tomographic demonstration of a spontaneous subcapsular hematoma due to a small renal cell carcinoma

    International Nuclear Information System (INIS)

    Hilton, S.; Bosniak, M.A.; Megibow, A.J.; Ambos, M.A.

    1981-01-01

    Computed tomography (CT) was able to demonstrate a small renal cell carcinoma as the cause of a spontaneous subcapsular hematoma. Angiographic and pathologic correlation were obtained. A review of the causes for nontraumatic renal subcapsular hematoma is included

  9. Spontaneous mutation rate in Chinese hamster cell clones differing in UV-sensitivity

    International Nuclear Information System (INIS)

    Manuilova, E.S.; Bagrova, A.M.; Moskovskij Gosudarstvennyj Univ.

    1983-01-01

    The spontaneous rate of appearance of mutations to 6-mercaptopurine (6 MP) resistence in the cells of CHR2 and CHs2 clones dofferent in sensitivity to lethal and matagenous effect of UV-rays, is investigated. Increased UV-sensitivity of CHs2 clone is caused by the violation of postreplicative DNA reparation. It is established that the purity of spontaneously occuring mutations in both clones turns out to be similar, i.e. (1.5-1.8)x10 -5 for the cell pergeneration. It is shown that the effect of postreplicative DNA reparation in the cells of chinese hamster is not connected with the increase of spontaneous mutation ability. The problem on the possible role of reparation in the mechanism of appearance of spontaneous and induced mutations in the cells of Chinese hamster with increased UV-sensitivity is discussed

  10. Spontaneous T Cell Proliferation: A Physiologic Process to Create and Maintain Homeostatic Balance and Diversity of the Immune System

    Science.gov (United States)

    Min, Booki

    2018-01-01

    Naive T lymphocytes undergo heterogeneous proliferative responses when introduced into lymphopenic hosts, referred to as “homeostatic proliferation” and “spontaneous proliferation.” Spontaneous proliferation is a unique process through which the immune system generates memory phenotype cells with increasing T cell receptors repertoire complexity. Here, the mechanisms that initiate and control spontaneous proliferation are discussed. PMID:29616038

  11. Spontaneous Epidural Haematoma in Sickle Cell Anaemia: Case ...

    African Journals Online (AJOL)

    He presented to our unit with seven days history of frontal headache which was preceded by an episode of vaso-occlusive crisis necessitating admission and blood transfusion in a peripheral hospital. There was. ABSTRACT. Non traumatic spontaneous epidural Haematoma is a rare and often unmentioned complication of ...

  12. Spontaneous transformation of murine oviductal epithelial cells: A model system to investigate the onset of fallopian-derived tumors

    Directory of Open Access Journals (Sweden)

    MIchael P. Endsley

    2015-07-01

    Full Text Available High-grade serous carcinoma (HGSC is the most lethal ovarian cancer histotype. The fallopian tube secretory epithelial cells (FTSECs are a proposed progenitor cell type. Genetically altered FTSECs form tumors in mice; however, a spontaneous HGSC model has not been described. Apart from a subpopulation of genetically predisposed women, most women develop ovarian cancer spontaneously, which is associated with aging and lifetime ovulations. A murine oviductal cell line (MOELOW was developed and continuously passaged in culture to mimic cellular aging (MOEHIGH. The MOEHIGH cellular model exhibited a loss of acetylated tubulin consistent with an outgrowth of secretory epithelial cells in culture. MOEHIGH cells proliferated significantly faster than MOELOW, and the MOEHIGH cells produced more 2D foci and 3D soft agar colonies as compared to MOELOW. MOEHIGH were xenografted into athymic female nude mice both in the subcutaneous and the intraperiteonal compartments. Only the subcutaneous grafts formed tumors that were negative for cytokeratin, but positive for oviductal markers such as oviductal glycoprotein 1 and Pax8. These tumors were considered to be poorly differentiated carcinoma. The differential molecular profiles between MOEHIGH and MOELOW were determined using RNA-Seq and confirmed by protein expression to uncover pathways important in transformation, like the p53 pathway, the FOXM1 pathway, WNT signaling, and splicing. MOEHIGH had enhanced protein expression of c-myc, Cyclin E, p53 and FOXM1 with reduced expression of p21. MOEHIGH were also less sensitive to cisplatin and DMBA, which induce lesions typically repaired by base-excision repair. A model of spontaneous tumorogenesis was generated starting with normal oviductal cells. Their transition to cancer involved alterations in pathways associated with high-grade serous cancer in humans.

  13. Comparative Analysis of Spontaneous and Stimulus-Evoked Calcium Transients in Proliferating and Fifferentiating Human Midbrain-Derived Stem Cells

    DEFF Research Database (Denmark)

    Johansen, Torben; Krabbe, Christina; Schmidt, Sissel Ida

    2017-01-01

    Spontaneous cytosolic calcium transients and oscillations have been reported in various tissues of nonhuman and human origin but not in human midbrain-derived stem cells. Using confocal microfluorimetry, we studied spontaneous calcium transients and calcium-regulating mechanisms in a human ventra...... cells that provides evidence for the mechanisms that are likely to be involved. We propose that the observed spontaneous calcium transients may contribute to mechanisms involved in cell proliferation, phenotypic differentiation, and general cell maturation....

  14. Circumcaval ureter with synchronous ipsilateral transitional cell ...

    African Journals Online (AJOL)

    We report a case of concomitant transitional cell carcinoma (TCC) in a circumcaval ureter and invasive bladder cancer. The diagnosis was based on the findings of excretory urography (IVU) and contrast-enhanced computed tomography (CT). IVU showed a typical J-shaped deformity in the dilated right proximal ureteric ...

  15. A Pathogenic Role for CD8+ T Cells in a Spontaneous Model of Demyelinating Disease

    DEFF Research Database (Denmark)

    Brisebois, Marcel; Zehntner, Simone P.; Estrada, José

    2006-01-01

    Transgenic (Tg) mice that overexpress the costimulatory ligand B7.2/CD86 on microglia spontaneously develop a T cell-mediated demyelinating disease. Characterization of the inflammatory infiltrates in the nervous tissue revealed a predominance of CD8+ T cells, suggesting a prominent role of this T...... cell subset in the pathology. In this study, we show that the same neurological disease occurred in Tg mice deficient in the generation of CD4+ T cells, with an earlier time of onset. Analysis of the CD8+ T cell repertoire at early stage of disease revealed the presence of selected clonal expansions...... pathogenesis. Collectively, our data indicate that the spontaneous demyelinating disease in this animal model occurs as a consequence of an inflammatory response initiated through the activation of CNS-specific CD8+ T cells by Tg expression of B7.2 within the target organ. Thus, autoreactive CD8+ T cells can...

  16. Transitional cell carcinoma express vitamin D receptors

    DEFF Research Database (Denmark)

    Hermann, G G; Andersen, C B

    1997-01-01

    Recently, vitamin D analogues have shown antineoplastic effect in several diseases. Vitamin D analogues exert its effect by interacting with the vitamin D receptor (VDR). Studies of VDR in transitional cell carcinoma (TCC) have not been reported. The purpose of the present study was therefore.......05). Similarly, also tumor grade appeared to be related to the number of cells expressing the receptor. Normal urothlium also expressed VDR but only with low intensity. Our study shows that TCC cells possess the VDR receptor which may make them capable to respond to stimulation with vitamin D, but functional...

  17. Spontaneous chromosome aberrations in cancer cells. Evidence of existence of hidden genetic lesions in genetic structures

    International Nuclear Information System (INIS)

    Poryadkova-Luchnik, N.A.; Kuz'mina, E.G.

    1996-01-01

    Chromosome aberrations spontaneously observed in cancer cells were quantitively studied under the effect of non-mutagenic (suboptimal temperature, low content of propilgallate and caffeine) and mutagenic (ionizing radiation) factors. Human larynx cancer cells during several years or gamma-irradiation were used to carry out experiments. The experiments linked with cloning of the initial population and investigation into chromosome aberrations in 22 clones demonstrated persuasively the occurrence of latent genetic lesions in cancer cells

  18. Cell Phenotype Transitions in Cardiovascular Calcification

    Directory of Open Access Journals (Sweden)

    Luis Hortells

    2018-03-01

    Full Text Available Cardiovascular calcification was originally considered a passive, degenerative process, however with the advance of cellular and molecular biology techniques it is now appreciated that ectopic calcification is an active biological process. Vascular calcification is the most common form of ectopic calcification, and aging as well as specific disease states such as atherosclerosis, diabetes, and genetic mutations, exhibit this pathology. In the vessels and valves, endothelial cells, smooth muscle cells, and fibroblast-like cells contribute to the formation of extracellular calcified nodules. Research suggests that these vascular cells undergo a phenotypic switch whereby they acquire osteoblast-like characteristics, however the mechanisms driving the early aspects of these cell transitions are not fully understood. Osteoblasts are true bone-forming cells and differentiate from their pluripotent precursor, the mesenchymal stem cell (MSC; vascular cells that acquire the ability to calcify share aspects of the transcriptional programs exhibited by MSCs differentiating into osteoblasts. What is unknown is whether a fully-differentiated vascular cell directly acquires the ability to calcify by the upregulation of osteogenic genes or, whether these vascular cells first de-differentiate into an MSC-like state before obtaining a “second hit” that induces them to re-differentiate down an osteogenic lineage. Addressing these questions will enable progress in preventative and regenerative medicine strategies to combat vascular calcification pathologies. In this review, we will summarize what is known about the phenotypic switching of vascular endothelial, smooth muscle, and valvular cells.

  19. Spontaneous T cell mediated keratoconjunctivitis in Aire-deficient mice

    Science.gov (United States)

    Yeh, S; de Paiva, C S; Hwang, C S; Trinca, K; Lingappan, A; Rafati, J K; Farley, W J; Li, D-Q; Pflugfelder, S C

    2013-01-01

    Background/aims Patients with autoimmune polyendocrinopathy-candiasis-ectodermal dystrophy (APECED) develop severe keratoconjunctivitis, corneal scarring and visual loss, but the precise pathogenesis is unknown. This study evaluated the ocular surface immune cell environment, conjunctival goblet cell density and response to desiccating environmental stress of the autoimmune regulatory (Aire) gene knockout murine model of APECED. Methods Aire-deficient and wild type (WT) mice were subjected to desiccating stress from a drafty, low-humidity environment and pharmacological inhibition of tear secretion for 5 days. Immune cell populations (CD4+, CD8+, CD11b+, CD45+) and goblet cell density were measured in ocular surface tissues and meibomian glands, and compared with baseline values. Results Greater CD4+ T cell populations were observed in the conjunctival epithelium of Aire-deficient mice (pAPECED. PMID:19429577

  20. Innexin gap junctions in nerve cells coordinate spontaneous contractile behavior in Hydra polyps.

    Science.gov (United States)

    Takaku, Yasuharu; Hwang, Jung Shan; Wolf, Alexander; Böttger, Angelika; Shimizu, Hiroshi; David, Charles N; Gojobori, Takashi

    2014-01-07

    Nerve cells and spontaneous coordinated behavior first appeared near the base of animal evolution in the common ancestor of cnidarians and bilaterians. Experiments on the cnidarian Hydra have demonstrated that nerve cells are essential for this behavior, although nerve cells in Hydra are organized in a diffuse network and do not form ganglia. Here we show that the gap junction protein innexin-2 is expressed in a small group of nerve cells in the lower body column of Hydra and that an anti-innexin-2 antibody binds to gap junctions in the same region. Treatment of live animals with innexin-2 antibody eliminates gap junction staining and reduces spontaneous body column contractions. We conclude that a small subset of nerve cells, connected by gap junctions and capable of synchronous firing, act as a pacemaker to coordinate the contraction of the body column in the absence of ganglia.

  1. Innexin gap junctions in nerve cells coordinate spontaneous contractile behavior in Hydra polyps

    KAUST Repository

    Takaku, Yasuharu

    2014-01-07

    Nerve cells and spontaneous coordinated behavior first appeared near the base of animal evolution in the common ancestor of cnidarians and bilaterians. Experiments on the cnidarian Hydra have demonstrated that nerve cells are essential for this behavior, although nerve cells in Hydra are organized in a diffuse network and do not form ganglia. Here we show that the gap junction protein innexin-2 is expressed in a small group of nerve cells in the lower body column of Hydra and that an anti-innexin-2 antibody binds to gap junctions in the same region. Treatment of live animals with innexin-2 antibody eliminates gap junction staining and reduces spontaneous body column contractions. We conclude that a small subset of nerve cells, connected by gap junctions and capable of synchronous firing, act as a pacemaker to coordinate the contraction of the body column in the absence of ganglia.

  2. Putative role of border cells in generating spontaneous morphological activity within Kölliker's organ.

    Science.gov (United States)

    Dayaratne, M W Nishani; Vlajkovic, Srdjan M; Lipski, Janusz; Thorne, Peter R

    2015-12-01

    Kölliker's organ is a transient epithelial structure, comprising a major part of the organ of Corti during pre-hearing stages of development. The auditory system is spontaneously active during development, which serves to retain and refine neural connections. Kölliker's organ is considered a key candidate for generating such spontaneous activity, most likely through purinergic (P2 receptor) signalling and inner hair cell (IHC) activation. Associated with the spontaneous neural activity, ATP released locally by epithelial cells induces rhythmic morphological changes within Kölliker's organ, the purpose of which is not understood. These changes are accompanied by a shift in cellular refractive index, allowing optical detection of this activity in real-time. Using this principle, we investigated the origin of spontaneous morphological activity within Kölliker's organ. Apical turns of Wistar rat cochleae (P9-11) were dissected, and the purinergic involvement was studied following acute tissue exposure to a P2 receptor agonist (ATPγS) and antagonist (suramin). ATPγS induced a sustained darkening throughout Kölliker's organ, reversed by suramin. This effect was most pronounced in the region closest to the inner hair cells, which also displayed the highest frequency of intrinsic morphological events. Additionally, suramin alone induced swelling of this region, suggesting a tight regulation of cell volume by ATP-mediated mechanisms. Histological analysis of cochlear tissues demonstrates the most profound volume changes in the border cell region immediately adjacent to the IHCs. Together, these results underline the role of purinergic signalling in initiating morphological events within Kölliker's organ, and suggest a key involvement of border cells surrounding IHCs in regulating this spontaneous activity. Copyright © 2015. Published by Elsevier B.V.

  3. Interactions between hair cells shape spontaneous otoacoustic emissions in a model of the tokay gecko's cochlea.

    Directory of Open Access Journals (Sweden)

    Michael Gelfand

    2010-06-01

    Full Text Available The hearing of tetrapods including humans is enhanced by an active process that amplifies the mechanical inputs associated with sound, sharpens frequency selectivity, and compresses the range of responsiveness. The most striking manifestation of the active process is spontaneous otoacoustic emission, the unprovoked emergence of sound from an ear. Hair cells, the sensory receptors of the inner ear, are known to provide the energy for such emissions; it is unclear, though, how ensembles of such cells collude to power observable emissions.We have measured and modeled spontaneous otoacoustic emissions from the ear of the tokay gecko, a convenient experimental subject that produces robust emissions. Using a van der Pol formulation to represent each cluster of hair cells within a tonotopic array, we have examined the factors that influence the cooperative interaction between oscillators.A model that includes viscous interactions between adjacent hair cells fails to produce emissions similar to those observed experimentally. In contrast, elastic coupling yields realistic results, especially if the oscillators near the ends of the array are weakened so as to minimize boundary effects. Introducing stochastic irregularity in the strength of oscillators stabilizes peaks in the spectrum of modeled emissions, further increasing the similarity to the responses of actual ears. Finally, and again in agreement with experimental findings, the inclusion of a pure-tone external stimulus repels the spectral peaks of spontaneous emissions. Our results suggest that elastic coupling between oscillators of slightly differing strength explains several properties of the spontaneous otoacoustic emissions in the gecko.

  4. Interactions between hair cells shape spontaneous otoacoustic emissions in a model of the tokay gecko's cochlea.

    Science.gov (United States)

    Gelfand, Michael; Piro, Oreste; Magnasco, Marcelo O; Hudspeth, A J

    2010-06-15

    The hearing of tetrapods including humans is enhanced by an active process that amplifies the mechanical inputs associated with sound, sharpens frequency selectivity, and compresses the range of responsiveness. The most striking manifestation of the active process is spontaneous otoacoustic emission, the unprovoked emergence of sound from an ear. Hair cells, the sensory receptors of the inner ear, are known to provide the energy for such emissions; it is unclear, though, how ensembles of such cells collude to power observable emissions. We have measured and modeled spontaneous otoacoustic emissions from the ear of the tokay gecko, a convenient experimental subject that produces robust emissions. Using a van der Pol formulation to represent each cluster of hair cells within a tonotopic array, we have examined the factors that influence the cooperative interaction between oscillators. A model that includes viscous interactions between adjacent hair cells fails to produce emissions similar to those observed experimentally. In contrast, elastic coupling yields realistic results, especially if the oscillators near the ends of the array are weakened so as to minimize boundary effects. Introducing stochastic irregularity in the strength of oscillators stabilizes peaks in the spectrum of modeled emissions, further increasing the similarity to the responses of actual ears. Finally, and again in agreement with experimental findings, the inclusion of a pure-tone external stimulus repels the spectral peaks of spontaneous emissions. Our results suggest that elastic coupling between oscillators of slightly differing strength explains several properties of the spontaneous otoacoustic emissions in the gecko.

  5. Histopathology of a spontaneously developing mast cell sarcoma in a Wistar rat

    NARCIS (Netherlands)

    Baselmans, A.H.C.; Kuijpers, M.H.M.; Dijk, J.E. van

    1996-01-01

    A case report is given of a very rare spontaneous mast cell tumor in the eyelid of the left eye of a female Wistar rat used in a long-term oral toxicity study. Metastasis of the tumor had occurred in the mandibular lymph nodes and in the liver. Clinically, the animal showed blepharospasm,

  6. Light-front quantized field theory: (an introduction). Spontaneous symmetry breaking. Phase transition in φ4 theory

    International Nuclear Information System (INIS)

    Srivastava, P.P.

    1993-01-01

    The field theory quantized on the light-front is compared with the conventional equal-time quantized theory. The arguments based on the micro causality principle would imply that the light-front field theory may become nonlocal with respect to the longitudinal coordinate even though the corresponding equal-time formulation is local. This is found to be the case for the scalar theory. The conventional instant form theory is sometimes required to be constrained by invoking external physical considerations; the analogous conditions seem to be already built in the theory on the light-front. In spite of the different mechanisms of the spontaneous symmetry breaking in the two forms of dynamics they result in the same physical content. The phase transition in (φ 4 ) 2 theory is also discussed. The symmetric vacuum state for vanishingly small couplings is found to turn into an unstable symmetric one when the coupling is increased and may result in a phase transition of the second order in contrast to the first order transition concluded from the usual variational methods. (author)

  7. Detection, characterization, and spontaneous differentiation in vitro of very small embryonic-like putative stem cells in adult mammalian ovary.

    Science.gov (United States)

    Parte, Seema; Bhartiya, Deepa; Telang, Jyoti; Daithankar, Vinita; Salvi, Vinita; Zaveri, Kusum; Hinduja, Indira

    2011-08-01

    The present study was undertaken to detect, characterize, and study differentiation potential of stem cells in adult rabbit, sheep, monkey, and menopausal human ovarian surface epithelium (OSE). Two distinct populations of putative stem cells (PSCs) of variable size were detected in scraped OSE, one being smaller and other similar in size to the surrounding red blood cells in the scraped OSE. The smaller 1-3 μm very small embryonic-like PSCs were pluripotent in nature with nuclear Oct-4 and cell surface SSEA-4, whereas the bigger 4-7 μm cells with cytoplasmic localization of Oct-4 and minimal expression of SSEA-4 were possibly the tissue committed progenitor stem cells. Pluripotent gene transcripts of Oct-4, Oct-4A, Nanog, Sox-2, TERT, and Stat-3 in human and sheep OSE were detected by reverse transcriptase-polymerase chain reaction. The PSCs underwent spontaneous differentiation into oocyte-like structures, parthenote-like structures, embryoid body-like structures, cells with neuronal-like phenotype, and embryonic stem cell-like colonies, whereas the epithelial cells transformed into mesenchymal phenotype by epithelial-mesenchymal transition in 3 weeks of OSE culture. Germ cell markers like c-Kit, DAZL, GDF-9, VASA, and ZP4 were immuno-localized in oocyte-like structures. In conclusion, as opposed to the existing view of OSE being a bipotent source of oocytes and granulosa cells, mammalian ovaries harbor distinct very small embryonic-like PSCs and tissue committed progenitor stem cells population that have the potential to develop into oocyte-like structures in vitro, whereas mesenchymal fibroblasts appear to form supporting granulosa-like somatic cells. Research at the single-cell level, including complete gene expression profiling, is required to further confirm whether postnatal oogenesis is a conserved phenomenon in adult mammals.

  8. Transitional cell carcinoma express vitamin D receptors

    DEFF Research Database (Denmark)

    Hermann, G G; Andersen, C B

    1997-01-01

    Recently, vitamin D analogues have shown antineoplastic effect in several diseases. Vitamin D analogues exert its effect by interacting with the vitamin D receptor (VDR). Studies of VDR in transitional cell carcinoma (TCC) have not been reported. The purpose of the present study was therefore.......05). Similarly, also tumor grade appeared to be related to the number of cells expressing the receptor. Normal urothlium also expressed VDR but only with low intensity. Our study shows that TCC cells possess the VDR receptor which may make them capable to respond to stimulation with vitamin D, but functional...... studies of vitamin D's effect on TCC cells in vitro are necessary before the efficacy of treatment with vitamin D analogues in TCC can be evaluated in patients....

  9. Spontaneously immortalised bovine mammary epithelial cells exhibit a distinct gene expression pattern from the breast cancer cells

    Directory of Open Access Journals (Sweden)

    Li Qianqian

    2010-10-01

    Full Text Available Abstract Background Spontaneous immortalisation of cultured mammary epithelial cells (MECs is an extremely rare event, and the molecular mechanism behind spontaneous immortalisation of MECs is unclear. Here, we report the establishment of a spontaneously immortalised bovine mammary epithelial cell line (BME65Cs and the changes in gene expression associated with BME65Cs cells. Results BME65Cs cells maintain the general characteristics of normal mammary epithelial cells in morphology, karyotype and immunohistochemistry, and are accompanied by the activation of endogenous bTERT (bovine Telomerase Reverse Transcriptase and stabilisation of the telomere. Currently, BME65Cs cells have been passed for more than 220 generations, and these cells exhibit non-malignant transformation. The expression of multiple genes was investigated in BME65Cs cells, senescent BMECs (bovine MECs cells, early passage BMECs cells and MCF-7 cells (a human breast cancer cell line. In comparison with early passage BMECs cells, the expression of senescence-relevant apoptosis-related gene were significantly changed in BME65Cs cells. P16INK4a was downregulated, p53 was low expressed and Bax/Bcl-2 ratio was reversed. Moreover, a slight upregulation of the oncogene c-Myc, along with an undetectable level of breast tumor-related gene Bag-1 and TRPS-1, was observed in BME65Cs cells while these genes are all highly expressed in MCF-7. In addition, DNMT1 is upregulated in BME65Cs. These results suggest that the inhibition of both senescence and mitochondrial apoptosis signalling pathways contribute to the immortality of BME65Cs cells. The expression of p53 and p16INK4a in BME65Cs was altered in the pattern of down-regulation but not "loss", suggesting that this spontaneous immortalization is possibly initiated by other mechanism rather than gene mutation of p53 or p16INK4a. Conclusions Spontaneously immortalised BME65Cs cells maintain many characteristics of normal BMEC cells and

  10. Spontaneous regression in an ulcerated CK7 positive Merkel cell carcinoma

    Directory of Open Access Journals (Sweden)

    Anza Khader

    2015-01-01

    Full Text Available Merkel cell carcinoma is an aggressive and frequently lethal tumor of the elderly, associated with sun exposure and immunosuppression which is less common in the dark-skinned. We report the case of a 40-year-old woman who presented with multiple slowly progressive, mildly itchy ulcerated plaques of size ranging from 2 × 3 cm to 5 × 7 cm on the left knee of 1 year duration. Skin biopsy showed diffuse dermal infiltration by small round cells with molding of cells and lymphocyte infiltration. The cells stained positive for cytokeratin (CK 20, CK7, neuron-specific enolase, and chromogranin. The skin lesions underwent spontaneous regression within 1 month of skin biopsy and have not recurred during the past 2 years. The immune mechanisms triggered by biopsy possibly explain the spontaneous regression.

  11. Gamma ray transitions in de-excitation of 252Cf spontaneous fission fragments

    International Nuclear Information System (INIS)

    Khan, N.A.; Rashid, K.; Ahmad, M.; Qureshi, I.E.; Alam, G.D.; Ali, A.; Bhatti, N.; Horsch, F.

    1983-11-01

    Gamma rays in the range from 60 keV to 730 keV have been observed following the spontaneous fission of 252 Cf, with high resolution Ge(Li) detector, full width at half maximum (FWHM) of 700 eV at 122 keV, in coincidence with the two fission fragments observed with surface barrier detectors. A total number of 18, 636, 549 events were recorded over a run period of about 150 hours stretching over three weeks. The events were sorted to generate gamma ray spectra belonging to 2 amu intervals gamma of the fragment masses and 6 MeV intervals of the total kinetic energy released. Some of the prominent gamma lines belonging to various masses of the fission fragments have been identified. For some gamma lines, the intensities have been evaluated as a function of the total kinetic energy of the fission fragments. (authors)

  12. Spontaneous calcium waves in granule cells in cerebellar slice cultures

    DEFF Research Database (Denmark)

    Apuschkin, Mia; Ougaard, Maria; Rekling, Jens C

    2013-01-01

    with MK-801. Whole-cell recordings during wave formation showed cyclic EPSP barrages with an amplitude of 10-20 mV concurrent with wave activity. Local non-propagating putative transglial waves were also present in the cultures, and could be reproduced by pressure application of ATP. We hypothesize...

  13. Transplants of cells engineered to produce GABA suppress spontaneous seizures

    Czech Academy of Sciences Publication Activity Database

    Thompson, K. W.; Suchomelová, Lucie

    2004-01-01

    Roč. 45, č. 1 (2004), s. 4-12 ISSN 0013-9580 Grant - others:VA Greater Los Angeles Healthcare System Research Service(US) MREP Institutional research plan: CEZ:AV0Z5011922 Keywords : cell transplantation * epilepsy * seizures Subject RIV: FH - Neurology Impact factor: 3.329, year: 2004

  14. Music as Transitional Object and Practice: Children's Spontaneous Musical Behaviors in the Subway

    Science.gov (United States)

    Custodero, Lori A.; Calì, Claudia; Diaz-Donoso, Adriana

    2016-01-01

    This study looks at children's music making in a public setting designed for society writ large. Although known to most children in the city, the subway presents a unique environment, both structurally predictable yet sonically dynamic; it is in continuous transition. Adopting Winnicott's psychoanalytical perspective, we make a case for viewing…

  15. Initial characterization of a spontaneous interferon secreted during growth and differentiation of Friend erythroleukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Revel, M.F.E.M.; Kimchi, A.

    1982-12-01

    A gradual increase in the level of 2',5'-oligoadenylate synthetase takes place in Friend erythroleukemia cells after a shiftdown in the rate of cell growth. The increase is about 5-fold after entry of cells into the stationary phase of growth, but much higher (25-fold) when reduction in growth accompanies cell differentiation. In the latter case, the enzyme increase is similar to that which can be induced in these cells by exogeneous interferon (IFN). The increase in 2',5'-oligoadenylate synthetase was shown to be due to a spontaneous secretion of IFN by the cells themselves: it is completely abolished if antiserum to murine type I IFN is added to the culture medium. In attempts to isolate some of this spontaneously secreted IFN, we show that it is stable at pH 2, not neutralized by antiserum to type II IFN, and that it also differs from the known IFN species induced by Sendai virus in Friend cells. The major component of this spontaneously secreted IFN is 20,000 M/sub r/, and differs from the corresponding virus-induced 20,000-M/sub r/ IFN by its lower affinity for antiserum to type I IFN and its antigenic characterization as BETA-murine IFN. The major component of the spontaneous IFN also exhibits a higher ratio of antigrowth to antiviral activity than the Sendai-induced IFNs. The authors suggest that Friend cells produce this specific type of IFN for the regulation of their growth and differentiation.

  16. Multiple origins of spontaneously arising micronuclei in HeLa cells: Direct evidence from long-term live cell imaging

    Energy Technology Data Exchange (ETDEWEB)

    Rao Xiaotang; Zhang Yingyin; Yi Qiyi; Hou Heli; Xu Bo; Chu Liang; Huang Yun; Zhang Wenrui [Laboratory of Molecular and Cell Genetics, Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 (China); Fenech, Michael [CSIRO Human Nutrition, PO Box 10041, Adelaide BC, Adelaide, SA 5000 (Australia); Shi Qinghua [Laboratory of Molecular and Cell Genetics, Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 (China)], E-mail: qshi@ustc.edu.cn

    2008-11-10

    Although micronuclei (MNi) are extensively used to evaluate genotoxic effects and chromosome instability, the most basic issue regarding their origins has not been completely addressed due to limitations of traditional methods. Recently, long-term live cell imaging was developed to monitor the dynamics of single cell in a real-time and high-throughput manner. In the present study, this state-of-the-art technique was employed to examine spontaneous micronucleus (MN) formation in untreated HeLa cells. We demonstrate that spontaneous MNi are derived from incorrectly aligned chromosomes in metaphase (displaced chromosomes, DCs), lagging chromosomes (LCs) and broken chromosome bridges (CBs) in later mitotic stages, but not nuclear buds in S phase. However, most of bipolar mitoses with DCs (91.29%), LCs (73.11%) and broken CBs (88.93%) did not give rise to MNi. Our data also show directly, for the first time, that MNi could originate spontaneously from (1) MNi already presented in the mother cells; (2) nuclear fragments that appeared during mitosis with CB; and (3) chromosomes being extruded into a minicell which fused with one of the daughter cells later. Quantitatively, most of MNi originated from LCs (63.66%), DCs (10.97%) and broken CBs (9.25%). Taken together, these direct evidences show that there are multiple origins for spontaneously arising MNi in HeLa cells and each mechanism contributes to overall MN formation to different extents.

  17. Multiple origins of spontaneously arising micronuclei in HeLa cells: Direct evidence from long-term live cell imaging

    International Nuclear Information System (INIS)

    Rao Xiaotang; Zhang Yingyin; Yi Qiyi; Hou Heli; Xu Bo; Chu Liang; Huang Yun; Zhang Wenrui; Fenech, Michael; Shi Qinghua

    2008-01-01

    Although micronuclei (MNi) are extensively used to evaluate genotoxic effects and chromosome instability, the most basic issue regarding their origins has not been completely addressed due to limitations of traditional methods. Recently, long-term live cell imaging was developed to monitor the dynamics of single cell in a real-time and high-throughput manner. In the present study, this state-of-the-art technique was employed to examine spontaneous micronucleus (MN) formation in untreated HeLa cells. We demonstrate that spontaneous MNi are derived from incorrectly aligned chromosomes in metaphase (displaced chromosomes, DCs), lagging chromosomes (LCs) and broken chromosome bridges (CBs) in later mitotic stages, but not nuclear buds in S phase. However, most of bipolar mitoses with DCs (91.29%), LCs (73.11%) and broken CBs (88.93%) did not give rise to MNi. Our data also show directly, for the first time, that MNi could originate spontaneously from (1) MNi already presented in the mother cells; (2) nuclear fragments that appeared during mitosis with CB; and (3) chromosomes being extruded into a minicell which fused with one of the daughter cells later. Quantitatively, most of MNi originated from LCs (63.66%), DCs (10.97%) and broken CBs (9.25%). Taken together, these direct evidences show that there are multiple origins for spontaneously arising MNi in HeLa cells and each mechanism contributes to overall MN formation to different extents

  18. Spontaneous Differentiation of Dental Pulp stem cells on Dental polymers

    Science.gov (United States)

    Bherwani, Aneel; Suarato, Giulia; Qin, Sisi; Chang, Chung-Cheh; Akhavan, Aaron; Spiegel, Joseph; Jurukovski, Vladimir; Rafailovich, Miriam; Simon, Marcia

    2012-02-01

    Dental pulp stem cells were plated on two dentally relevant materials i.e. PMMA commonly used for denture and Titanium used for implants. In both cases, we probed for the role of surface interaction and substrate morphology. Different films of PMMA were spun cast directly onto Si wafers; PMMA fibers of different diameters were electro spun onto some of these substrates. Titanium metal was evaporated onto Si surfaces using an electron beam evaporator. In addition, on some surfaces, P4VP nanofibers were spun cast. DPSC were grown in alpha-MEM supplemented with 10% fetal bovine serum, 0.2mM L-ascorbic acid 2-phosphate, 2mm glutamine and 10mM beta-glycerol phosphate either with or without 10nM dexamethasone. After 21 days samples were examined using confocal microscopy of cells and by scanning electron microscopy (SEM) and Energy dispersive X-ray Analysis (EDAX). In the case of Titanium biomineralization was observed independent of dexamethasone, where the deposits were templated along the fibers. Minimal biomineralization was observed on flat Titanium and PMMA samples. Markers of osteogenesis and specific signaling pathways are being evaluated by RT-PCR, which are up regulated on each surface, to understand the fundamental manner in which surfaces interact with cell differentiation.

  19. How variable is a spontaneous mutation rate in cultured mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Boesen, Jan J.B.; Niericker, Matthieu J.; Dieteren, Nicole; Simons, Jo W.I.M. (MGC-Dept. of Radiation Genetics and Chemical Mutagenesis, State Univ. of Leiden (Netherlands))

    1994-05-01

    The Luria-Delbrueck fluctuation analysis provides a method to estimate mutation rates and is commonly applied in somatic cell genetics and in cancer biology. We developed an assay for a Luria-Delbrueck fluctuation analysis using the mouse lymphoma cell line, GRSL13. As these cells grow in suspension, one can handle hundreds of parallel cultures using multiwell dishes and dispensers. This assay thereby allows not only an accurate determination of the mutation rate per cell generation but also makes it possible to determine at which time after seeding mutations take place. Using approx. 8000 parallel cultures it has been possible to test whether the mutation rate is constant during the assay. It has been found that the spontaneous mutation rate of GRSL13 cells decreases in the course of a fluctuation test from 2x10[sup -6] to about 2x10[sup -7]/cell/generation. It was shown that this increased replication fidelity may partly be caused by cell density: maintenance of cells at high cell density resulted in a spontaneous mutation rate of 0.7[+-]4.0x10[sup -7] compared to 4.0[+-]3.1x10[sup -7] for the standard protocol. In contrast, growing the cells at extremely low cell density resulted in an enhanced mutation rate of 7.7[+-]1.3x10[sup -7]. Thus altogether the mutation rate can vary from 2x10[sup -6] to 0.7x10[sup -7] (approx. 30-fold). These results show that the spontaneous mutation rate is not constant, but highly dependent on experimental conditions. As incomplete expression and metabolic cooperation cannot explain the findings, the data suggest that the fidelity of DNA replication is not fixed but open to variation. Hence, determination of replication infidelity in cultured cells needs rigorous standardization or/and application of controlled variation in culture conditions.

  20. Protons Sensitize Epithelial Cells to Mesenchymal Transition

    Science.gov (United States)

    Wang, Minli; Hada, Megumi; Saha, Janapriya; Sridharan, Deepa M.; Pluth, Janice M.; Cucinotta, Francis A.

    2012-01-01

    Proton radiotherapy has gained more favor among oncologists as a treatment option for localized and deep-seated tumors. In addition, protons are a major constituent of the space radiation astronauts receive during space flights. The potential for these exposures to lead to, or enhance cancer risk has not been well studied. Our objective is to study the biological effects of low energy protons on epithelial cells and its propensity to enhance transforming growth factor beta 1 (TGFβ1)-mediated epithelial-mesenchymal transition (EMT), a process occurring during tumor progression and critical for invasion and metastasis. Non-transformed mink lung epithelial cells (Mv1Lu) and hTERT- immortalized human esophageal epithelial cells (EPC) were used in this study. EMT was identified by alterations in cell morphology, EMT-related gene expression changes determined using real-time PCR, and EMT changes in specific cellular markers detected by immunostaining and western blotting. Although TGFβ1 treatment alone is able to induce EMT in both Mv1Lu and EPC cells, low energy protons (5 MeV) at doses as low as 0.1 Gy can enhance TGFβ1 induced EMT. Protons alone can also induce a mild induction of EMT. SD208, a potent TGFβ Receptor 1 (TGFβR1) kinase inhibitor, can efficiently block TGFβ1/Smad signaling and attenuate EMT induction. We suggest a model for EMT after proton irradiation in normal and cancerous tissue based on our results that showed that low and high doses of protons can sensitize normal human epithelial cells to mesenchymal transition, more prominently in the presence of TGFβ1, but also in the absence of TGFβ1. PMID:22844446

  1. Low threshold amplified spontaneous emission from tin oxide quantum dots: a instantiation of dipole transition silence semiconductors.

    Science.gov (United States)

    Pan, Shu Sheng; Yu, Siu Fung; Zhang, Wen Fei; Zhu, Hai; Lu, Wei; Jin, Li Min

    2013-12-07

    Direct bandgap semiconductors, such as In2O3, Cu2O, and SnO2, have enormous applications in photochemistry, photovoltaics, and optoelectronics. Due to the same parity of conduction and valence bands, the dipole transition is silent in these direct bandgap semiconductors. The low band-to-band transition efficiency prevents them from high intensity light emission or absorption. Here, we report the fabrication of SnO2 quantum dots (QDs) with sizes less than the exciton Bohr radius by a facile "top-down" strategy based on laser fragmentation of SnO in water. The SnO2 QDs shows exciton emission at ∼300 nm with a high quantum yield of ~17%. Amplified spontaneous exciton emission is also achieved from a thin layer of SnO2 QDs dispersed in PEG400 on a quartz substrate. Therefore, we have shown that SnO2 QDs can be a potential luminescent material suitable for the realization of ultraviolet B lasing devices.

  2. Spontaneous Orbital-Selective Mott Transitions and the Jahn-Teller Metal of A3C60

    Science.gov (United States)

    Hoshino, Shintaro; Werner, Philipp

    2017-04-01

    The alkali-doped fullerides A3C60 are half-filled three-orbital Hubbard systems which exhibit an unconventional superconducting phase next to a Mott insulator. While the pairing is understood to arise from an effectively negative Hund coupling, the highly unusual Jahn-Teller metal near the Mott transition, featuring both localized and itinerant electrons, has not been understood. This property is consistently explained by a previously unrecognized phenomenon: the spontaneous transition of multiorbital systems with negative Hund coupling into an orbital-selective Mott state. This symmetry-broken state, which has no ordinary orbital moment, is characterized by an orbital-dependent two-body operator (the double occupancy) or an orbital-dependent kinetic energy and may be regarded as a diagonal-order version of odd-frequency superconductivity. We propose that the recently discovered Jahn-Teller metal phase of Rbx Cs3 -xC60 is an experimental realization of this novel state of matter.

  3. BAFF promotes autoantibody production via TACI-dependent activation of transitional B cells

    Science.gov (United States)

    Jacobs, Holly M.; Thouvenel, Christopher D.; Leach, Sarah; Arkatkar, Tanvi; Metzler, Genita; Scharping, Nicole E.; Kolhatkar, Nikita S.; Rawlings, David J.; Jackson, Shaun W.

    2016-01-01

    Mice overexpressing B cell activating factor of the TNF family (BAFF) develop systemic autoimmunity characterized by class-switched anti-nuclear antibodies. Transmembrane activator and CAML interactor (TACI) signals are critical for BAFF-mediated autoimmunity, but the B cell developmental subsets undergoing TACI-dependent activation in settings of excess BAFF remains unclear. We now report that, whereas surface TACI expression is usually limited to mature B cells, excess BAFF promotes the expansion of TACI-expressing transitional B cells. TACIhi transitional cells from BAFF-Tg mice are characterized by an activated, cycling phenotype; and the TACIhi cell subset is specifically enriched for autoreactivity, expresses activation-induced cytidine deaminase (AID) and T-bet and exhibits evidence of somatic hypermutation. Consistent with a potential contribution to BAFF-mediated humoral autoimmunity, TACIhi transitional B cells from BAFF-Tg mice spontaneously produce class-switched autoantibodies ex vivo. These combined findings highlight a novel mechanism whereby BAFF promotes humoral autoimmunity via direct, TACI-dependent activation of transitional B cells. PMID:27022196

  4. Cutting Edge: BAFF Promotes Autoantibody Production via TACI-Dependent Activation of Transitional B Cells.

    Science.gov (United States)

    Jacobs, Holly M; Thouvenel, Christopher D; Leach, Sarah; Arkatkar, Tanvi; Metzler, Genita; Scharping, Nicole E; Kolhatkar, Nikita S; Rawlings, David J; Jackson, Shaun W

    2016-05-01

    Mice overexpressing B cell activating factor of the TNF family (BAFF) develop systemic autoimmunity characterized by class-switched anti-nuclear Abs. Transmembrane activator and CAML interactor (TACI) signals are critical for BAFF-mediated autoimmunity, but the B cell developmental subsets undergoing TACI-dependent activation in settings of excess BAFF remain unclear. We report that, although surface TACI expression is usually limited to mature B cells, excess BAFF promotes the expansion of TACI-expressing transitional B cells. TACI(+) transitional cells from BAFF-transgenic mice are characterized by an activated, cycling phenotype, and the TACI(+) cell subset is specifically enriched for autoreactivity, expresses activation-induced cytidine deaminase and T-bet, and exhibits evidence of somatic hypermutation. Consistent with a potential contribution to BAFF-mediated humoral autoimmunity, TACI(+) transitional B cells from BAFF-transgenic mice spontaneously produce class-switched autoantibodies ex vivo. These combined findings highlight a novel mechanism through which BAFF promotes humoral autoimmunity via direct, TACI-dependent activation of transitional B cells. Copyright © 2016 by The American Association of Immunologists, Inc.

  5. A developmentally plastic adult mouse kidney cell line spontaneously generates multiple adult kidney structures

    International Nuclear Information System (INIS)

    Webb, Carol F.; Ratliff, Michelle L.; Powell, Rebecca; Wirsig-Wiechmann, Celeste R.; Lakiza, Olga; Obara, Tomoko

    2015-01-01

    Despite exciting new possibilities for regenerative therapy posed by the ability to induce pluripotent stem cells, recapitulation of three-dimensional kidneys for repair or replacement has not been possible. ARID3a-deficient mouse tissues generated multipotent, developmentally plastic cells. Therefore, we assessed the adult mouse ARID3a−/− kidney cell line, KKPS5, which expresses renal progenitor surface markers as an alternative cell source for modeling kidney development. Remarkably, these cells spontaneously developed into multicellular nephron-like structures in vitro, and engrafted into immunocompromised medaka mesonephros, where they formed mouse nephron structures. These data implicate KKPS5 cells as a new model system for studying kidney development. - Highlights: • An ARID3a-deficient mouse kidney cell line expresses multiple progenitor markers. • This cell line spontaneously forms multiple nephron-like structures in vitro. • This cell line formed mouse kidney structures in immunocompromised medaka fish kidneys. • Our data identify a novel model system for studying kidney development

  6. Cycle length restitution in sinoatrial node cells: a theory for understanding spontaneous action potential dynamics.

    Directory of Open Access Journals (Sweden)

    Patric Glynn

    Full Text Available Normal heart rhythm (sinus rhythm is governed by the sinoatrial node, a specialized and highly heterogeneous collection of spontaneously active myocytes in the right atrium. Sinoatrial node dysfunction, characterized by slow and/or asynchronous pacemaker activity and even failure, is associated with cardiovascular disease (e.g. heart failure, atrial fibrillation. While tremendous progress has been made in understanding the molecular and ionic basis of automaticity in sinoatrial node cells, the dynamics governing sinoatrial nodel cell synchrony and overall pacemaker function remain unclear. Here, a well-validated computational model of the mouse sinoatrial node cell is used to test the hypothesis that sinoatrial node cell dynamics reflect an inherent restitution property (cycle length restitution that may give rise to a wide range of behavior from regular periodicity to highly complex, irregular activation. Computer simulations are performed to determine the cycle length restitution curve in the computational model using a newly defined voltage pulse protocol. The ability of the restitution curve to predict sinoatrial node cell dynamics (e.g., the emergence of irregular spontaneous activity and susceptibility to termination is evaluated. Finally, ionic and tissue level factors (e.g. ion channel conductances, ion concentrations, cell-to-cell coupling that influence restitution and sinoatrial node cell dynamics are explored. Together, these findings suggest that cycle length restitution may be a useful tool for analyzing cell dynamics and dysfunction in the sinoatrial node.

  7. A developmentally plastic adult mouse kidney cell line spontaneously generates multiple adult kidney structures

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Carol F., E-mail: carol-webb@omrf.org [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Ratliff, Michelle L., E-mail: michelle-ratliff@omrf.org [Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Powell, Rebecca, E-mail: rebeccapowell@gmail.com [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Wirsig-Wiechmann, Celeste R., E-mail: celeste-wirsig@ouhsc.edu [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Lakiza, Olga, E-mail: olga-lakiza@ouhsc.edu [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Obara, Tomoko, E-mail: tomoko-obara@ouhsc.edu [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2015-08-07

    Despite exciting new possibilities for regenerative therapy posed by the ability to induce pluripotent stem cells, recapitulation of three-dimensional kidneys for repair or replacement has not been possible. ARID3a-deficient mouse tissues generated multipotent, developmentally plastic cells. Therefore, we assessed the adult mouse ARID3a−/− kidney cell line, KKPS5, which expresses renal progenitor surface markers as an alternative cell source for modeling kidney development. Remarkably, these cells spontaneously developed into multicellular nephron-like structures in vitro, and engrafted into immunocompromised medaka mesonephros, where they formed mouse nephron structures. These data implicate KKPS5 cells as a new model system for studying kidney development. - Highlights: • An ARID3a-deficient mouse kidney cell line expresses multiple progenitor markers. • This cell line spontaneously forms multiple nephron-like structures in vitro. • This cell line formed mouse kidney structures in immunocompromised medaka fish kidneys. • Our data identify a novel model system for studying kidney development.

  8. Endo- and exocytic rate constants for spontaneous and protein kinase C-activated T cell receptor cycling

    DEFF Research Database (Denmark)

    Menné, Charlotte; Møller Sørensen, Tine; Siersma, Volkert

    2002-01-01

    To determine the rate constants of spontaneous and activated TCR cycling, we examined TCR endo- and exocytosis in the human T cell line Jurkat by three different methods. Using a simple kinetic model for TCR cycling and non-linear regression analyses, we found that the spontaneous endocytic rate...

  9. National Fuel Cell Bus Program : Accelerated Testing Report, AC Transit

    Science.gov (United States)

    2009-01-01

    This is an evaluation of hydrogen fuel cell transit buses operating at AC Transit in revenue service since March 20, 2006 compared to similar diesel buses operating from the same depot. This evaluation report includes results from November 2007 throu...

  10. Interactions between Hair Cells Shape Spontaneous Otoacoustic Emissions in a Model of the Tokay Gecko's Cochlea

    OpenAIRE

    Gelfand, Michael; Piro, Oreste; Magnasco, Marcelo O.; Hudspeth, A. J.

    2010-01-01

    Background The hearing of tetrapods including humans is enhanced by an active process that amplifies the mechanical inputs associated with sound, sharpens frequency selectivity, and compresses the range of responsiveness. The most striking manifestation of the active process is spontaneous otoacoustic emission, the unprovoked emergence of sound from an ear. Hair cells, the sensory receptors of the inner ear, are known to provide the energy for such emissions; it is unclear, though, how ens...

  11. Spontaneous Neuronal Activity in Developing Neocortical Networks: From Single Cells to Large-Scale Interactions.

    Science.gov (United States)

    Luhmann, Heiko J; Sinning, Anne; Yang, Jenq-Wei; Reyes-Puerta, Vicente; Stüttgen, Maik C; Kirischuk, Sergei; Kilb, Werner

    2016-01-01

    Neuronal activity has been shown to be essential for the proper formation of neuronal circuits, affecting developmental processes like neurogenesis, migration, programmed cell death, cellular differentiation, formation of local and long-range axonal connections, synaptic plasticity or myelination. Accordingly, neocortical areas reveal distinct spontaneous and sensory-driven neuronal activity patterns already at early phases of development. At embryonic stages, when immature neurons start to develop voltage-dependent channels, spontaneous activity is highly synchronized within small neuronal networks and governed by electrical synaptic transmission. Subsequently, spontaneous activity patterns become more complex, involve larger networks and propagate over several neocortical areas. The developmental shift from local to large-scale network activity is accompanied by a gradual shift from electrical to chemical synaptic transmission with an initial excitatory action of chloride-gated channels activated by GABA, glycine and taurine. Transient neuronal populations in the subplate (SP) support temporary circuits that play an important role in tuning early neocortical activity and the formation of mature neuronal networks. Thus, early spontaneous activity patterns control the formation of developing networks in sensory cortices, and disturbances of these activity patterns may lead to long-lasting neuronal deficits.

  12. Spontaneous formation of tumorigenic hybrids between breast cancer and multipotent stromal cells is a source of tumor heterogeneity.

    Science.gov (United States)

    Rappa, Germana; Mercapide, Javier; Lorico, Aurelio

    2012-06-01

    Breast cancer progression involves cancer cell heterogeneity, with generation of invasive/metastatic breast cancer cells within populations of nonmetastatic cells of the primary tumor. Sequential genetic mutations, epithelial-to-mesenchymal transition, interaction with local stroma, and formation of hybrids between cancer cells and normal bone marrow-derived cells have been advocated as tumor progression mechanisms. We report herein the spontaneous in vitro formation of heterotypic hybrids between human bone marrow-derived multipotent stromal cells (MSCs) and two different breast carcinoma cell lines, MDA-MB-231 (MDA) and MA11. Hybrids showed predominantly mesenchymal morphological characteristics, mixed gene expression profiles, and increased DNA ploidy. Both MA11 and MDA hybrids were tumorigenic in immunodeficient mice, and some MDA hybrids had an increased metastatic capacity. Both in culture and as xenografts, hybrids underwent DNA ploidy reduction and morphological reversal to breast carcinoma-like morphological characteristics, while maintaining a mixed breast cancer-mesenchymal expression profile. Analysis of coding single-nucleotide polymorphisms by RNA sequencing revealed genetic contributions from both parental partners to hybrid tumors and metastasis. Because MSCs migrate and localize to breast carcinoma, our findings indicate that formation of MSC-breast cancer cell hybrids is a potential mechanism of the generation of invasive/metastatic breast cancer cells. Our findings reconcile the fusion theory of cancer progression with the common observation that breast cancer metastases are generally aneuploid, but not tetraploid, and are histopathologically similar to the primary neoplasm. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  13. Omega 3 fatty acids increase spontaneous release of cytosolic components from tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Jenski, L.J.; Sturdevant, L.K.; Ehringer, W.D.; Stillwell, W. (Department of Biology, Indiana University-Purdue University, Indianapolis (United States))

    1991-05-01

    Mice fed menhaden (fish) oil or coconut oil-rich diets were inoculated intraperitoneally with a rapidly growing leukemia, T27A. After one week, the tumor cells were harvested, and 51Cr was used to label intracellular molecules. Spontaneous release of 51Cr was used as a measure of plasma membrane permeability. Compared to cells from mice fed coconut oil (rich in saturated fatty acids), tumor cells from mice fed menhaden oil (rich in long chain polyunsaturated omega 3 fatty acids) showed an increased level of spontaneous 51Cr release, which was exacerbated by increased temperature and reduced by extracellular protein. At physiological salt concentrations, the released 51Cr was detected in particles of approximately 2700 daltons. Enhanced permeability correlated with the incorporation of dietary (fish oil) omega 3 polyunsaturated fatty acids docosahexaenoic and eicosapentaenoic acid into the tumor cells. The results demonstrate that omega 3 fatty acids are incorporated into cellular constituents of tumor cells and change properties associated with the plasma membrane. This result suggests that dietary manipulation may be used to enhance tumor cell permeability and contribute to tumor eradication.

  14. Omega 3 fatty acids increase spontaneous release of cytosolic components from tumor cells

    International Nuclear Information System (INIS)

    Jenski, L.J.; Sturdevant, L.K.; Ehringer, W.D.; Stillwell, W.

    1991-01-01

    Mice fed menhaden (fish) oil or coconut oil-rich diets were inoculated intraperitoneally with a rapidly growing leukemia, T27A. After one week, the tumor cells were harvested, and 51Cr was used to label intracellular molecules. Spontaneous release of 51Cr was used as a measure of plasma membrane permeability. Compared to cells from mice fed coconut oil (rich in saturated fatty acids), tumor cells from mice fed menhaden oil (rich in long chain polyunsaturated omega 3 fatty acids) showed an increased level of spontaneous 51Cr release, which was exacerbated by increased temperature and reduced by extracellular protein. At physiological salt concentrations, the released 51Cr was detected in particles of approximately 2700 daltons. Enhanced permeability correlated with the incorporation of dietary (fish oil) omega 3 polyunsaturated fatty acids docosahexaenoic and eicosapentaenoic acid into the tumor cells. The results demonstrate that omega 3 fatty acids are incorporated into cellular constituents of tumor cells and change properties associated with the plasma membrane. This result suggests that dietary manipulation may be used to enhance tumor cell permeability and contribute to tumor eradication

  15. Prolonged Expansion Induces Spontaneous Neural Progenitor Differentiation from Human Gingiva-Derived Mesenchymal Stem Cells.

    Science.gov (United States)

    Rajan, Thangavelu Soundara; Scionti, Domenico; Diomede, Francesca; Piattelli, Adriano; Bramanti, Placido; Mazzon, Emanuela; Trubiani, Oriana

    2017-12-01

    Neural crest-derived mesenchymal stem cells (MSCs) obtained from dental tissues received considerable interest in regenerative medicine, particularly in nerve regeneration owing to their embryonic origin and ease of harvest. Proliferation efficacy and differentiation capacity into diverse cell lineages propose dental MSCs as an in vitro tool for disease modeling. In this study, we investigated the spontaneous differentiation efficiency of dental MSCs obtained from human gingiva tissue (hGMSCs) into neural progenitor cells after extended passaging. At passage 41, the morphology of hGMSCs changed from typical fibroblast-like shape into sphere-shaped cells with extending processes. Next-generation transcriptomics sequencing showed increased expression of neural progenitor markers such as NES, MEIS2, and MEST. In addition, de novo expression of neural precursor genes, such as NRN1, PHOX2B, VANGL2, and NTRK3, was noticed in passage 41. Immunocytochemistry results showed suppression of neurogenesis repressors TP53 and p21, whereas Western blot results revealed the expression of neurotrophic factors BDNF and NT3 at passage 41. Our results showed the spontaneous efficacy of hGMSCs to differentiate into neural precursor cells over prolonged passages and that these cells may assist in producing novel in vitro disease models that are associated with neural development.

  16. Evaluation of Th1 and Th17 cells cytokines in cell culture stimulated in women with recurrent spontaneous abortion

    OpenAIRE

    Y Varghaiyan; H Hadi neduoshan; A Aflatoonian; A Mirghanizadeh; S Najafi

    2013-01-01

    Introduction: Various immunological abnormalities have been reported in women with RSA of unknown aetiologies including autoimmune abnormalities and increased cellular immunity such as elevated natural killer (NK) , Th1 and Th17 cell levels. Th17 and Th1 cells play a central role during inflammation. Th1 cells product cytokines IFN-γ, IL-2 and Th17 cells mainly cytokines IL-17A, F, IL-22. The aim of this study is evaluation of Th1 and Th17 activity in women with recurrent spontaneous abortion...

  17. Spontaneous cytotoxic T-Cell reactivity against indoleamine 2,3-dioxygenase-2

    DEFF Research Database (Denmark)

    Sørensen, Rikke Bæk; Køllgaard, Tania; Andersen, Rikke Sick

    2011-01-01

    Several lines of data have suggested a possible link between the indoleamine 2,3-dioxygenase (IDO)-like protein IDO2 and cancer. First, IDO2 expression has been described in human tumors, including renal, gastric, colon, and pancreatic tumors. Second, the apparent selective inhibition of IDO2...... in mouse models of cancer in a nontoxic fashion. Here, we describe the immunogenicity of IDO2 by showing the presence of spontaneous cytotoxic T-cell reactivity against IDO2 in peripheral blood of both healthy donors and cancer patients. Furthermore, we show that these IDO2-specific T cells are cytotoxic...

  18. Dentate gyrus mossy cells control spontaneous convulsive seizures and spatial memory.

    Science.gov (United States)

    Bui, Anh D; Nguyen, Theresa M; Limouse, Charles; Kim, Hannah K; Szabo, Gergely G; Felong, Sylwia; Maroso, Mattia; Soltesz, Ivan

    2018-02-16

    Temporal lobe epilepsy (TLE) is characterized by debilitating, recurring seizures and an increased risk for cognitive deficits. Mossy cells (MCs) are key neurons in the hippocampal excitatory circuit, and the partial loss of MCs is a major hallmark of TLE. We investigated how MCs contribute to spontaneous ictal activity and to spatial contextual memory in a mouse model of TLE with hippocampal sclerosis, using a combination of optogenetic, electrophysiological, and behavioral approaches. In chronically epileptic mice, real-time optogenetic modulation of MCs during spontaneous hippocampal seizures controlled the progression of activity from an electrographic to convulsive seizure. Decreased MC activity is sufficient to impede encoding of spatial context, recapitulating observed cognitive deficits in chronically epileptic mice. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  19. Generation and characterization of a spontaneously immortalized endothelial cell line from mice microcirculation.

    Science.gov (United States)

    Loiola, Rodrigo A; Torres, Tathiany C; Aburaya, Carla M; Landgraf, Maristella A; Landgraf, Richardt G; Bosco Pesquero, João; Fernandes, Liliam

    2013-05-01

    Endothelial cells from microvasculature are directly involved in a large number of vascular diseases; however, culture of these cells is problematic, since most methodologies employ proteolytic enzymes or mechanical techniques, leading to cell damage and contamination of endothelial cultures with other cellular types. Besides, primary cultured cells have a short life span in vitro and undergo replicative senescence after 3-4 passages, limiting long-term studies. In the present work we report the generation of a spontaneously immortalized endothelial culture obtained from mice pulmonary capillaries. Firstly, primary (third passage) and immortalized (100th) cultures were established. Further, monoclonal populations were obtained by serial dilutions from immortalized cultures. Cells were analyzed according to: (1) morphological appearance, (2) expression of specific endothelial markers by fluorescent staining [von Willebrand Factor (vWF), endothelial nitric oxide synthase (eNOS), angiotensin converting enzyme (ACE) and Ulex europaeus (UEA-1)] and by flow cytometry (endoglin, VE-cadherin and VCAM-1), and (3) release of nitric oxide (NO), assessed by the specific fluorescent dye DAF-2 DA, and prostacyclin (PGI2), quantified by enzyme immune assay. In both cultures cells grew in monolayers and presented cobblestone appearance at confluence. Positive staining for vWF, eNOS, ACE and UEA-1 was detected in cloned as well as in early-passage cultured cells. Similarly, cultures presented equal expressions of endoglin, VE-cadherin and VCAM-1. Values of NO and PGI2 levels did not differ between cultures. From these results we confirm that the described spontaneously immortalized endothelial cell line is capable of unlimited growth and retains typical morphological and functional properties exhibited by primary cultured cells. Therefore, the endothelial cell line described in the present study can become a suitable tool in the field of endothelium research and can be useful for

  20. Reduced graphene oxide-coated hydroxyapatite composites stimulate spontaneous osteogenic differentiation of human mesenchymal stem cells

    Science.gov (United States)

    Lee, Jong Ho; Shin, Yong Cheol; Jin, Oh Seong; Kang, Seok Hee; Hwang, Yu-Shik; Park, Jong-Chul; Hong, Suck Won; Han, Dong-Wook

    2015-07-01

    Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite the potential biomedical applications of graphene and its derivatives, only limited information is available regarding their osteogenic activity. This study concentrates upon the effects of reduced graphene oxide (rGO)-coated hydroxyapatite (HAp) composites on osteogenic differentiation of hMSCs. The average particle sizes of HAp and rGO were 1270 +/- 476 nm and 438 +/- 180 nm, respectively. When coated on HAp particulates, rGO synergistically enhanced spontaneous osteogenic differentiation of hMSCs, without hampering their proliferation. This result was confirmed by determining alkaline phosphatase activity and mineralization of calcium and phosphate as early and late stage markers of osteogenic differentiation. It is suggested that rGO-coated HAp composites can be effectively utilized as dental and orthopedic bone fillers since these graphene-based particulate materials have potent effects on stimulating the spontaneous differentiation of MSCs and show superior bioactivity and osteoinductive potential.Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite

  1. Blockage of spontaneous Ca2+ oscillation causes cell death in intraerythrocitic Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Masahiro Enomoto

    Full Text Available Malaria remains one of the world's most important infectious diseases and is responsible for enormous mortality and morbidity. Resistance to antimalarial drugs is a challenging problem in malaria control. Clinical malaria is associated with the proliferation and development of Plasmodium parasites in human erythrocytes. Especially, the development into the mature forms (trophozoite and schizont of Plasmodium falciparum (P. falciparum causes severe malaria symptoms due to a distinctive property, sequestration which is not shared by any other human malaria. Ca(2+ is well known to be a highly versatile intracellular messenger that regulates many different cellular processes. Cytosolic Ca(2+ increases evoked by extracellular stimuli are often observed in the form of oscillating Ca(2+ spikes (Ca(2+ oscillation in eukaryotic cells. However, in lower eukaryotic and plant cells the physiological roles and the molecular mechanisms of Ca(2+ oscillation are poorly understood. Here, we showed the observation of the inositol 1,4,5-trisphospate (IP(3-dependent spontaneous Ca(2+ oscillation in P. falciparum without any exogenous extracellular stimulation by using live cell fluorescence Ca(2+ imaging. Intraerythrocytic P. falciparum exhibited stage-specific Ca(2+ oscillations in ring form and trophozoite stages which were blocked by IP(3 receptor inhibitor, 2-aminoethyl diphenylborinate (2-APB. Analyses of parasitaemia and parasite size and electron micrograph of 2-APB-treated P. falciparum revealed that 2-APB severely obstructed the intraerythrocytic maturation, resulting in cell death of the parasites. Furthermore, we confirmed the similar lethal effect of 2-APB on the chloroquine-resistant strain of P. falciparum. To our best knowledge, we for the first time showed the existence of the spontaneous Ca(2+ oscillation in Plasmodium species and clearly demonstrated that IP(3-dependent spontaneous Ca(2+ oscillation in P. falciparum is critical for the development

  2. Position-dependent patterning of spontaneous action potentials in immature cochlear inner hair cells

    Science.gov (United States)

    Johnson, Stuart L.; Eckrich, Tobias; Kuhn, Stephanie; Zampini, Valeria; Franz, Christoph; Ranatunga, Kishani M.; Roberts, Terri P.; Masetto, Sergio; Knipper, Marlies; Kros, Corné J.; Marcotti, Walter

    2011-01-01

    Spontaneous action potential activity is crucial for mammalian sensory system development. In the auditory system, patterned firing activity has been observed in immature spiral ganglion cells and brain-stem neurons and is likely to depend on cochlear inner hair cell (IHC) action potentials. It remains uncertain whether spiking activity is intrinsic to developing IHCs and whether it shows patterning. We found that action potentials are intrinsically generated by immature IHCs of altricial rodents and that apical IHCs exhibit bursting activity as opposed to more sustained firing in basal cells. We show that the efferent neurotransmitter ACh, by fine-tuning the IHC’s resting membrane potential (Vm), is crucial for the bursting pattern in apical cells. Endogenous extracellular ATP also contributes to the Vm of apical and basal IHCs by activating SK2 channels. We hypothesize that the difference in firing pattern along the cochlea instructs the tonotopic differentiation of IHCs and auditory pathway. PMID:21572434

  3. Role of spinal glial cells in bee-toxin-induced spontaneous pain, hyperalgesia, and inflammation

    Directory of Open Access Journals (Sweden)

    Yao LU

    2012-08-01

    Full Text Available Objective To observe the effects of intrathecal injection of fluorocitrate, a glial metabolism inhibitor, on bee-toxin-induced spontaneous pain, hyperalgesia and inflammatory response. Methods Forty adult male SD rats with intrathecal catheterization were randomly divided into five groups (8 each: (1 bee-toxin alone group; (2 vehicle (solvent group; (3 low dose (1nmol fluorocitrate group; (4 middle dose (10nmol fluorocitrate group; (5 high dose (50nmol fluorocitrate group. After the measurement of rat paw withdrawal mechanical threshold (PWMT and paw volume (PV, the drug or vehicle was administered intrathecally. Twenty minutes later, bee-toxin (0.2mg/50μl was intraplantarly injected into the left hind paw of every rat, and spontaneous flinching reflexes (SFR were observed instantly for 1 hour. Two hours later, PWMT and PV were measured again. Results Intraplantar injection of bee-toxin into one hind paw of rat induced persistent SFR lasting for 1 hour, with PWMT decreased and PV increased in the injected paw. Compared with control group, pretreatment with intrathecal injection of fluorocitrate produced a significant inhibition of bee-toxin-induced persistent SFR (P < 0.05, P < 0.01, decreased the PWMT in a dose-dependent manner (P < 0.05, but it had no effect on bee-toxin-induced paw edema. Conclusion Activation of spinal glial cells may participate in bee-toxin-induced spontaneous pain and mechanical hyperalgesia, but not inflammatory response.

  4. Isolation of stem-like cells from spontaneous feline mammary carcinomas: Phenotypic characterization and tumorigenic potential

    Energy Technology Data Exchange (ETDEWEB)

    Barbieri, Federica; Wurth, Roberto [Section of Pharmacology, Dept. of Internal Medicine Di.M.I., and Center of Excellence for Biomedical Research - University of Genova, Viale Benedetto XV, 2, 16132 Genova (Italy); Ratto, Alessandra; Campanella, Chiara; Vito, Guendalina [Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle D' Aosta, National Reference Center of Veterinary and Comparative Oncology (CEROVEC), Piazza Borgo Pila, 16129, Genova (Italy); Thellung, Stefano [Section of Pharmacology, Dept. of Internal Medicine Di.M.I., and Center of Excellence for Biomedical Research - University of Genova, Viale Benedetto XV, 2, 16132 Genova (Italy); Daga, Antonio [Laboratory of Translational Oncology, IRCCS Azienda Ospedaliera Universitaria San Martino - IST- Istituto Nazionale Ricerca sul Cancro, L.go R. Benzi, 10, 16132 Genova Italy (Italy); Cilli, Michele [Animal Facility, IRCCS Azienda Ospedaliera Universitaria San Martino - IST- Istituto Nazionale Ricerca sul Cancro, L.go R. Benzi, 10, 16132 Genova Italy (Italy); Ferrari, Angelo [Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle D' Aosta, National Reference Center of Veterinary and Comparative Oncology (CEROVEC), Piazza Borgo Pila, 16129, Genova (Italy); Florio, Tullio, E-mail: tullio.florio@unige.it [Section of Pharmacology, Dept. of Internal Medicine Di.M.I., and Center of Excellence for Biomedical Research - University of Genova, Viale Benedetto XV, 2, 16132 Genova (Italy)

    2012-04-15

    Current carcinogenesis theory states that only a small subset of tumor cells, the cancer stem cells or tumor initiating cells (TICs), are responsible for tumor formation and progression. Human breast cancer-initiating cells have been identified as CD44-expressing cells, which retain tumorigenic activity and display stem cell-like properties. Spontaneous feline mammary carcinoma (FMC) is an aggressive cancer, which shows biological similarities to the human tumor counterpart. We report the isolation and phenotypic characterization of FMC-derived stem/progenitor cells, showing in vitro self-renewal, long-lasting proliferation and in vivo tumorigenicity. Twenty-one FMC samples were collected, histologically classified and characterized for the expression of Ki67, EGFR, ER-{alpha} and CD44, by immunohistochemistry. By culture in stem cell permissive conditions, we isolated, from 13 FMCs, a CD44-positive subpopulation able to survive and proliferate in vitro as mammospheres of different sizes and morphologies. When injected in NOD/SCID mice, FMC stem-like cells initiate tumors, generating cell heterogeneity and recapitulating the original histotype. In serum-containing medium, spheroid cells showed differentiation properties as shown by morphological changes, the loss of CD44 expression and tumorigenic potential. These data show that stem-defined culture of FMC enriches for TICs and validate the use of these cells as a suitable model for comparative oncology studies of mammary biology and testing therapeutic strategies aimed at eradicating TICs. -- Highlights: Black-Right-Pointing-Pointer Feline mammary carcinoma contain a sub-population of stem-like cells expressing CD44 Black-Right-Pointing-Pointer These grow as spheres in serum-free medium and self-renew Black-Right-Pointing-Pointer Isolated stem-like cancer cells initiate tumor in immunodeficient mice Black-Right-Pointing-Pointer Xenografted tumors are phenotypically similar to the original tumor Black

  5. p53 regulates the proliferation, differentiation and spontaneous transformation of mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Armesilla-Diaz, Alejandro, E-mail: aarmesilla@cib.csic.es [Department of Cellular and Molecular Physiopathology, Centro de Investigaciones Biologicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid (Spain); Elvira, Gema; Silva, Augusto [Department of Cellular and Molecular Physiopathology, Centro de Investigaciones Biologicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid (Spain)

    2009-12-10

    Mesenchymal stem cells (MSC) have been extensively studied and gained wide popularity due to their therapeutic potential. Spontaneous transformation of MSC, from both human and murine origin, has been reported in many studies. MSC transformation depends on the culture conditions, the origin of the cells and the time on culture; however, the precise biological characteristics involved in this process have not been fully defined yet. In this study, we investigated the role of p53 in the biology and transformation of murine bone marrow (BM)-derived MSC. We demonstrate that the MSC derived from p53KO mice showed an augmented proliferation rate, a shorter doubling time and also morphologic and phenotypic changes, as compared to MSC derived from wild-type animals. Furthermore, the MSC devoid of p53 had an increased number of cells able to generate colonies. In addition, not only proliferation but also MSC differentiation is controlled by p53 since its absence modifies the speed of the process. Moreover, genomic instability, changes in the expression of c-myc and anchorage independent growth were also observed in p53KO MSC. In addition, the absence of p53 implicates the spontaneous transformation of MSC in long-term cultures. Our results reveal that p53 plays a central role in the biology of MSC.

  6. Isolation of stem-like cells from spontaneous feline mammary carcinomas: Phenotypic characterization and tumorigenic potential

    International Nuclear Information System (INIS)

    Barbieri, Federica; Wurth, Roberto; Ratto, Alessandra; Campanella, Chiara; Vito, Guendalina; Thellung, Stefano; Daga, Antonio; Cilli, Michele; Ferrari, Angelo; Florio, Tullio

    2012-01-01

    Current carcinogenesis theory states that only a small subset of tumor cells, the cancer stem cells or tumor initiating cells (TICs), are responsible for tumor formation and progression. Human breast cancer-initiating cells have been identified as CD44-expressing cells, which retain tumorigenic activity and display stem cell–like properties. Spontaneous feline mammary carcinoma (FMC) is an aggressive cancer, which shows biological similarities to the human tumor counterpart. We report the isolation and phenotypic characterization of FMC-derived stem/progenitor cells, showing in vitro self-renewal, long-lasting proliferation and in vivo tumorigenicity. Twenty-one FMC samples were collected, histologically classified and characterized for the expression of Ki67, EGFR, ER-α and CD44, by immunohistochemistry. By culture in stem cell permissive conditions, we isolated, from 13 FMCs, a CD44-positive subpopulation able to survive and proliferate in vitro as mammospheres of different sizes and morphologies. When injected in NOD/SCID mice, FMC stem-like cells initiate tumors, generating cell heterogeneity and recapitulating the original histotype. In serum-containing medium, spheroid cells showed differentiation properties as shown by morphological changes, the loss of CD44 expression and tumorigenic potential. These data show that stem-defined culture of FMC enriches for TICs and validate the use of these cells as a suitable model for comparative oncology studies of mammary biology and testing therapeutic strategies aimed at eradicating TICs. -- Highlights: ► Feline mammary carcinoma contain a sub-population of stem-like cells expressing CD44 ► These grow as spheres in serum-free medium and self-renew ► Isolated stem-like cancer cells initiate tumor in immunodeficient mice ► Xenografted tumors are phenotypically similar to the original tumor ► Upon differentiation, cells grow as monolayers, loosing the tumorigenic potential

  7. Umbilical cord CD71+ erythroid cells are reduced in neonates born to women in spontaneous preterm labor.

    Science.gov (United States)

    Gomez-Lopez, Nardhy; Romero, Roberto; Xu, Yi; Miller, Derek; Unkel, Ronald; C MacKenzie, Tippi; Frascoli, Michela; Hassan, Sonia S

    2016-10-01

    Preterm neonates are highly susceptible to infection. Neonatal host defense against infection seems to be maintained by the temporal presence of immunosuppressive CD71+ erythroid cells. The aim of this study was to investigate whether umbilical cord CD71+ erythroid cells are reduced in neonates born to women who undergo spontaneous preterm labor/birth. Umbilical cord blood samples (n=155) were collected from neonates born to women who delivered preterm with (n=39) and without (n=12) spontaneous labor or at term with (n=82) and without (n=22) spontaneous labor. Time-matched maternal peripheral blood samples were also included (n=111). Mononuclear cells were isolated from these samples, and CD71+ erythroid cells were identified and quantified as CD3-CD235a+CD71+ cells by flow cytometry. (i) The proportion of CD71+ erythroid cells was 50-fold higher in cord blood than in maternal blood; (ii) a reduced number and frequency of umbilical cord CD71+ erythroid cells were found in neonates born to women who underwent spontaneous preterm labor compared to those born to women who delivered preterm without labor; (iii) umbilical cord CD71+ erythroid cells were fewer in neonates born to term pregnancies, regardless of the process of labor, than in those born to women who delivered preterm without labor; and (iv) no differences were seen in umbilical cord CD71+ erythroid cells between neonates born to women who underwent spontaneous preterm labor and those born to women who delivered at term with labor. Umbilical cord CD71+ erythroid cells are reduced in neonates born to women who had undergone spontaneous preterm labor. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  8. Spontaneous oscillations of cell voltage, power density, and anode exit CO concentration in a PEM fuel cell.

    Science.gov (United States)

    Lu, Hui; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2011-10-28

    The spontaneous oscillations of the cell voltage and output power density of a PEMFC (with PtRu/C anode) using CO-containing H(2) streams as anodic fuels have been observed during galvanostatic operating. It is ascribed to the dynamic coupling of the CO adsorption (poisoning) and the electrochemical CO oxidation (reactivating) processes in the anode chamber of the single PEMFC. Accompanying the cell voltage and power density oscillations, the discrete CO concentration oscillations at the anode outlet of the PEMFC were also detected, which directly confirms the electrochemical CO oxidation taking place in the anode chamber during galvanostatic operating. This journal is © the Owner Societies 2011

  9. Spontaneous transition rates for electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2) and magnetic quadrupole (M2) transitions for He-like calcium and sulfur ions

    International Nuclear Information System (INIS)

    Kingston, A.E.; Norrington, P.H.; Boone, A.W.

    2002-01-01

    The spontaneous decay rates for the electric dipole (E1), electric quadrupole (E2), magnetic dipole (M1) and magnetic quadrupole (M2) transitions between all of the 1s 2 , 1s2 l and 1s3 l states have been obtained for helium-like calcium and sulfur ions. To assess the accuracy of the calculations, the transition probabilities were calculated using two sets of configuration interaction wavefunctions. One set of wavefunctions was generated using the fully relativistic GRASP code and the other was obtained using CIV3, in which relativistic effects are introduced using the Breit-Pauli approximation. The transition rates, A values, oscillator strengths and line strengths from our two calculations are found to be similar and to compare very well with other recent results for Δn=1 or 2 transitions. For Δn=0 transitions the agreement is much less good; this is mainly due to differences in the calculated excitation energies. (author)

  10. Spontaneous gene transfection of human bone cells using 3D mineralized alginate-chitosan macrocapsules.

    Science.gov (United States)

    Green, David W; Kim, Eun-Jung; Jung, Han-Sung

    2015-09-01

    The effectiveness of nonviral gene therapy remains uncertain because of low transfection efficiencies and high toxicities compared with viral-based strategies. We describe a simple system for transient transfection of continuous human cell lines, with low toxicity, using mineral-coated chitosan and alginate capsules. As proof-of-concept, we demonstrate transfection of Saos-2 and MG63 human osteosarcoma continuous cell lines with gfp, LacZ reporter genes, and a Sox-9 carrying plasmid, to illustrate expression of a functional gene with therapeutic relevance. We show that continuous cell lines transfect with significant efficiency of up to 65% possibly through the interplay between chitosan and DNA complexation and calcium/phosphate-induced translocation into cells entrapped within the 3D polysaccharide based environment, as evidenced by an absence of transfection in unmineralized and chitosan-free capsules. We demonstrated that our transfection system was equally effective at transfection of primary human bone marrow stromal cells. To illustrate, the Sox-9, DNA plasmid was spontaneously expressed in primary human bone marrow stromal cells at 7 days with up to 90% efficiency in two repeats. Mineralized polysaccharide macrocapsules are gene delivery vehicles with a number of biological and practical advantages. They are highly efficient at self-transfecting primary bone cells, with programmable spatial and temporal delivery prospects, premineralized bone-like environments, and have no cytotoxic effects, as compared with many other nonviral systems. © 2015 Wiley Periodicals, Inc.

  11. Subcutaneous Panniculitis-Like T-Cell Lymphoma (SPTL in a Child with Spontaneous Resolution

    Directory of Open Access Journals (Sweden)

    Achiléa L. Bittencourt

    2011-01-01

    Full Text Available Subcutaneous panniculitis-like T-cell lymphomas (SPTLs α/β are rare in childhood. The present report refers to a case of a 7-year-old male child presenting an extensive skin lesion that began when he was 5 years of age. Two biopsies were evaluated using the CD3, CD4, CD8, CD56, βF1, and TIA markers. A dense infiltrate of CD3+, CD4−, CD8+, CD56−, βF1+, and TIA+ pleomorphic lymphocytes was found in the subcutis. The previous biopsy showed cytophagic histiocytic panniculitis with a small focus on CD8+ and βF1+ malignant cells. The lesion regressed spontaneously. This case shows that prognosis may be excellent in SPTL (α/β. On the other hand, it also serves as an alert that a biopsy performed in an area of cytophagic panniculitis may lead to misdiagnosis.

  12. Impact of Molecular Orientation and Spontaneous Interfacial Mixing on the Performance of Organic Solar Cells

    KAUST Repository

    Ngongang Ndjawa, Guy Olivier

    2015-07-28

    A critically important question that must be answered to understand how organic solar cells operate and should be improved is how the orientation of the donor and acceptor molecules at the interface influences exciton diffusion, exciton dissociation by electron transfer and recombination. It is exceedingly difficult to probe the orientation in bulk heterojunctions because there are many interfaces and they are arranged with varying angles with respect to the substrate. One of the best ways to study the interface is to make bilayer solar cells with just one donor-acceptor interface. Zinc phthalocyanine is particularly interesting to study because its orientation can be adjusted by using a 2-nm-thick copper iodide seed layer before it is deposited. Previous studies have claimed that solar cells in which fullerene acceptor molecules touch the face of zinc phthalocyanine have more current than ones in which the fullerenes touch the edge of zinc phthalocyanine because of suppressed recombination. We have more thoroughly characterized the system using in situ x-ray photoelectron spectroscopy and found that the interfaces are not as sharp as previous studies claimed when formed at room temperature or above. Fullerenes have a much stronger tendency to mix into the face-on films than into the edge-on films. Moreover we show that almost all of the increase in the current with face-on films can be attributed to improved exciton diffusion and to the formation of a spontaneously mixed interface, not suppressed recombination. This work highlights the importance of spontaneous interfacial molecular mixing in organic solar cells, the extent of which depends on molecular orientation of frontier molecules in donor domains.

  13. Characterization of spontaneous excitatory synaptic currents in salamander retinal ganglion cells.

    Science.gov (United States)

    Taylor, W R; Chen, E; Copenhagen, D R

    1995-01-01

    1. Spontaneous excitatory postsynaptic currents (sEPSCs) were recorded under voltage-clamp conditions. Consistent with activation of non-NMDA-type glutamate receptors, the sEPSCs reversed at potentials above 0 mV, were blocked by 1 microM CNQX and prolonged by 2 mM aniracetam. 2. The peak conductance of the averaged sEPSCs (n = 70-400) was 130 +/- 60 pS (mean +/- S.D.; 17 cells, ranging from 70 to 290 pS). Amplitude distributions were skewed towards larger amplitudes. 3. The decay of individual and mean sEPSCs was exponential with a mean time constant (tau d) of 3.75 +/- 0.84 ms (n = 13), which was voltage independent. The 10-90% rise time of the sEPSCs was 1.30 +/- 0.44 ms (n = 13). There was no correlation between sEPSC rise time and tau d suggesting that dendritic filtering alone did not shape the time course of sEPSCs. 4. Light-evoked EPSCs in these retinal ganglion cells are mediated by concomitant activation of NMDA and non-NMDA receptors; however, no NMDA component was discerned in the sEPSCs, even when recording at -96 mV in Mg(2+)-free solutions. The decay time course was not altered by 20 microM AP7, an NMDA antagonist, nor was an NMDA component unmasked by adding glycine or D-serine. These results suggest that NMDA and non-NMDA receptors are not coactivated by a single vesicle of transmitter during spontaneous release, and thus are probably not colocalized in the postsynaptic membrane at the sites of spontaneous release. 5. The sEPSCs were an order of magnitude faster than the non-NMDA receptor-mediated EPSCs evoked by light stimuli, and it is proposed that the EPSC time course is determined largely by the extended time course of release of synaptic vesicles from bipolar cells. The quantal content of a light-evoked non-NMDA receptor-mediated EPSC in an on-off cell is about 200 quanta. Images Figure 6 PMID:7562636

  14. Modeling the Mechanics of Cell Division: Influence of Spontaneous Membrane Curvature, Surface Tension, and Osmotic Pressure

    Directory of Open Access Journals (Sweden)

    Elena Beltrán-Heredia

    2017-05-01

    Full Text Available Many cell division processes have been conserved throughout evolution and are being revealed by studies on model organisms such as bacteria, yeasts, and protozoa. Cellular membrane constriction is one of these processes, observed almost universally during cell division. It happens similarly in all organisms through a mechanical pathway synchronized with the sequence of cytokinetic events in the cell interior. Arguably, such a mechanical process is mastered by the coordinated action of a constriction machinery fueled by biochemical energy in conjunction with the passive mechanics of the cellular membrane. Independently of the details of the constriction engine, the membrane component responds against deformation by minimizing the elastic energy at every constriction state following a pathway still unknown. In this paper, we address a theoretical study of the mechanics of membrane constriction in a simplified model that describes a homogeneous membrane vesicle in the regime where mechanical work due to osmotic pressure, surface tension, and bending energy are comparable. We develop a general method to find approximate analytical expressions for the main descriptors of a symmetrically constricted vesicle. Analytical solutions are obtained by combining a perturbative expansion for small deformations with a variational approach that was previously demonstrated valid at the reference state of an initially spherical vesicle at isotonic conditions. The analytic approximate results are compared with the exact solution obtained from numerical computations, getting a good agreement for all the computed quantities (energy, area, volume, constriction force. We analyze the effects of the spontaneous curvature, the surface tension and the osmotic pressure in these quantities, focusing especially on the constriction force. The more favorable conditions for vesicle constriction are determined, obtaining that smaller constriction forces are required for positive

  15. Chemoablated mouse seminiferous tubular cells enriched for very small embryonic-like stem cells undergo spontaneous spermatogenesis in vitro.

    Science.gov (United States)

    Anand, Sandhya; Patel, Hiren; Bhartiya, Deepa

    2015-04-18

    Extensive research is ongoing to empower cancer survivors to have biological parenthood. For this, sperm are cryopreserved prior to therapy and in younger children testicular biopsies are cryopreserved with a hope to mature the germ cells into sperm later on for assisted reproduction. In addition, lot of hope was bestowed on pluripotent embryonic and induced pluripotent stem cells to differentiate into sperm and oocytes. However, obtaining functional gametes from pluripotent stem cells still remains a distant dream and major bottle-neck appears to be their inefficient differentiation into primordial germ cells (PGCs). There exists yet another population of pluripotent stem cells termed very small embryonic-like stem cells (VSELs) in adult body organs including gonads. We have earlier reported that busulphan (25 mg/Kg) treatment to 4 weeks old mice destroys actively dividing cells and sperm but VSELs survive and differentiate into sperm when a healthy niche is provided in vivo. Mouse testicular VSELs that survived busulphan treatment were cultured for 3 weeks. A mix of surviving cells in seminiferous tubules (VSELs, possibly few spermatogonial stem cells and Sertoli cells) were cultured using Sertoli cells conditioned medium containing fetal bovine serum, follicle stimulating hormone and with no additional growth factors. Stem cells underwent proliferation and clonal expansion in culture and spontaneously differentiated into sperm whereas Sertoli cells attached and provided a somatic support. Transcripts specific for various stages of spermatogenesis were up-regulated by qRT-PCR studies on day 7 suggesting VSELs (Sca1) and SSCs (Gfra) proliferate (Pcna), undergo spermatogenesis (spermatocyte specific marker prohibitin), meiosis (Scp3) and differentiate into sperm (post-meiotic marker protamine). Process of spermatogenesis and spermiogenesis was replicated in vitro starting with testicular cells that survived busulphan treatment. We have earlier reported similar

  16. BC Transit Fuel Cell Bus Project: Evaluation Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-02-01

    This report evaluates a fuel cell electric bus demonstration led by British Columbia Transit (BC Transit) in Whistler, Canada. BC Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory to evaluate the buses in revenue service. This evaluation report covers two years of revenue service data on the buses from April 2011 through March 2013.

  17. Measurements of a vortex transitional ndro Josephson memory cell

    International Nuclear Information System (INIS)

    Tahara, S.; Ishida, I.; Hidaka, M.; Nagasawa, S.; Ajisawa, Y.; Wada, Y.

    1988-01-01

    A novel vortex transitional NDRO Jospehson memory cell has been successfully fabricated and tested. The memory cell consists of two superconducting loops and a two-junction interferometer gate as a sense gate. The superconducting loop contains one Josephson junction and inductances, and stores single flux quantum. The memory cell employs vortex transitions in the superconducting loops for writing and reading data. The memory cell chips have been fabricated using niobium planarization process. The +-21 percent address signal current margin and the +-33 percent sense gate current margin have been obtained experimentally. The memory operation of the cell driven by the two-junction interferometer gates has been accurately demonstrated

  18. Spontaneous class switch recombination in B cell lymphopoiesis generates aberrant switch junctions and is increased after VDJ rearrangement.

    Science.gov (United States)

    Edry, Efrat; Koralov, Sergei B; Rajewsky, Klaus; Melamed, Doron

    2007-11-15

    Mature B cells replace the mu constant region of the H chain with a downstream isotype in a process of class switch recombination (CSR). Studies suggest that CSR induction is limited to activated mature B cells in the periphery. Recently, we have shown that CSR spontaneously occur in B lymphopoiesis. However, the mechanism and regulation of it have not been defined. In this study, we show that spontaneous CSR occurs at all stages of B cell development and generates aberrant joining of the switch junctions as revealed by: 1) increased load of somatic mutations around the CSR break points, 2) reduced sequence overlaps at the junctions, and 3) excessive switch region deletion. In addition, we found that incidence of spontaneous CSR is increased in cells carrying VDJ rearrangements. Our results reveal major differences between spontaneous CSR in developing B cells and CSR induced in mature B cells upon activation. These differences can be explained by deregulated expression or function of activation-induced cytidine deaminase early in B cell development.

  19. The spontaneous and stimulated nitroblue tetrazolium (NBT) tests in mononuclear cells of patients with tuberculosis.

    Science.gov (United States)

    Dubaniewicz, A; Hoppe, A

    2004-01-01

    The aim of this study was to evaluate the ability of the NBT reduction by non- and BCG-stimulated monocytes isolated from peripheral blood persons with pulmonary tuberculosis (TB) before treatment, after two-month antituberculosis therapy and in an inactive stage of this disease. The spontaneous and induced NBT tests were done in 24 healthy individuals and 59 patients with pulmonary tuberculosis: 33 before antituberculosis treatment and 26 with inactive stage of TB. Mononuclear cells were isolated from peripheral blood by the Bøyum method and identified by histochemical assay. The abilities of non- and BCG-stimulated monocytes of NBT reduction were estimated by the method according to Park with Szczylik modification. In an active state of TB and after 2 months treatment, the non- and BCG-stimulated monocytes capacity to reduce NBT was found to be significantly increased in comparison to controls. The NBT test parameters in the absence of cell stimulation and after administration of BCG were comparable in active TB and after two-month treatment. In an inactive TB, the ability of NBT reduction by non- and BCG-stimulated monocytes was comparable to the controls. The stimulation of mononuclear cells accompanied by the significantly higher capacity of monocytes to reduce NBT in controls and in TB patients with post-tuberculous changes in the lungs. These results of the spontaneous and induced NBT tests adequately reflect the status of the host's specific reactivity during tuberculosis and can be a simple, inexpensive and useful method for monitoring antituberculosis treatment.

  20. Establishment of an animal model of spontaneous cervical lymph node metastasis of laryngeal squamous cell carcinoma and obtaining laryngocarcinoma cells with high metastatic potential.

    Science.gov (United States)

    Chen, L W; Wang, J L; Zhang, L Y; Yang, S M; Li, C S; Yu, N; Zhao W, J D; Zhao, L D; Li, K; Liu, M B; Zhai, S Q

    2013-01-01

    To establish an animal model of spontaneous cervical lymph node metastasis of laryngeal squamous cell carcinoma and obtain laryngocarcinoma cells with high metastatic potential, laryngeal squamous cell carcinoma cell line HEP-2 in logarithmic phase were inoculated under the lingual margin mucosa of nude mice. HEP-2 cells metastasized to the cervical lymph nodes were isolated, cultured, and re-inoculated under the lingual margin mucosa of nude mice twice. The tumor formation in the tongue and in the cervical lymph nodes was confirmed by pathological examination. Carcinoma cells' ability of invasion and migration was detected by transwell assay. Human specific Alu sequences were detected by PCR, which indicated that the tumor cells originated from human laryngeal squamous cell carcinoma cell line HEP-2. Finally, an animal model of spontaneous lymph node metastasis of laryngeal squamous cell carcinoma was successfully established. Laryngeal squamous cell carcinoma cells with high metastatic potential to lymph nodes were obtained through repeated inoculations. .

  1. A human breast cell model of pre-invasive to invasive transition

    Energy Technology Data Exchange (ETDEWEB)

    Bissell, Mina J; Rizki, Aylin; Weaver, Valerie M.; Lee, Sun-Young; Rozenberg, Gabriela I.; Chin, Koei; Myers, Connie A.; Bascom, Jamie L.; Mott, Joni D.; Semeiks, Jeremy R.; Grate, Leslie R.; Mian, I. Saira; Borowsky, Alexander D.; Jensen, Roy A.; Idowu, Michael O.; Chen, Fanqing; Chen, David J.; Petersen, Ole W.; Gray, Joe W.; Bissell, Mina J.

    2008-03-10

    A crucial step in human breast cancer progression is the acquisition of invasiveness. There is a distinct lack of human cell culture models to study the transition from pre-invasive to invasive phenotype as it may occur 'spontaneously' in vivo. To delineate molecular alterations important for this transition, we isolated human breast epithelial cell lines that showed partial loss of tissue polarity in three-dimensional reconstituted-basement membrane cultures. These cells remained non-invasive; however, unlike their non-malignant counterparts, they exhibited a high propensity to acquire invasiveness through basement membrane in culture. The genomic aberrations and gene expression profiles of the cells in this model showed a high degree of similarity to primary breast tumor profiles. The xenograft tumors formed by the cell lines in three different microenvironments in nude mice displayed metaplastic phenotypes, including squamous and basal characteristics, with invasive cells exhibiting features of higher grade tumors. To find functionally significant changes in transition from pre-invasive to invasive phenotype, we performed attribute profile clustering analysis on the list of genes differentially expressed between pre-invasive and invasive cells. We found integral membrane proteins, transcription factors, kinases, transport molecules, and chemokines to be highly represented. In addition, expression of matrix metalloproteinases MMP-9,-13,-15,-17 was up regulated in the invasive cells. Using siRNA based approaches, we found these MMPs to be required for the invasive phenotype. This model provides a new tool for dissection of mechanisms by which pre-invasive breast cells could acquire invasiveness in a metaplastic context.

  2. Moringa oleifera-rich diet and T cell calcium signaling in spontaneously hypertensive rats.

    Science.gov (United States)

    Attakpa, E S; Bertin, G A; Chabi, N W; Ategbo, J-M; Seri, B; Khan, N A

    2017-11-24

    Moringa oleifera is a plant whose fruits, roots and leaves have been advocated for traditional medicinal uses. The physicochemical analysis shows that Moringa oleifera contains more dietary polyunsaturated fatty acids (PUFA) than saturated fatty acids (SFA). The consumption of an experimental diet enriched with Moringa oleifera extracts lowered blood pressure in spontaneously hypertensive rats (SHR), but not in normotensive Wistar-Kyoto (WKY) rats as compared to rats fed an unsupplemented control diet. Anti-CD3-stimulated T cell proliferation was diminished in both strains of rats fed the Moringa oleifera. The experimental diet lowered secretion of interleukin-2 in SHR, but not in WKY rats compared with rats fed the control diet. Studies of platelets from patients with primary hypertension and from SHR support the notion that the concentration of intracellular free calcium [Ca(2+)](i) is modified in both clinical and experimental hypertension. We observed that the basal, [Ca(2+)](i) was lower in T cells of SHR than in those of WKY rats fed the control diet. Feeding the diet with Moringa oleifera extracts to WKY rats did not alter basal [Ca(2+)](i) in T cells but increased basal [Ca(2+)](i) in SHR. Our study clearly demonstrated that Moringa oleifera exerts antihypertensive effects by inhibiting the secretion of IL-2 and modulates T cell calcium signaling in hypertensive rats.

  3. Cellular Origin of Spontaneous Ganglion Cell Spike Activity in Animal Models of Retinitis Pigmentosa

    Directory of Open Access Journals (Sweden)

    David J. Margolis

    2011-01-01

    Full Text Available Here we review evidence that loss of photoreceptors due to degenerative retinal disease causes an increase in the rate of spontaneous ganglion spike discharge. Information about persistent spike activity is important since it is expected to add noise to the communication between the eye and the brain and thus impact the design and effective use of retinal prosthetics for restoring visual function in patients blinded by disease. Patch-clamp recordings from identified types of ON and OFF retinal ganglion cells in the adult (36–210 d old rd1 mouse show that the ongoing oscillatory spike activity in both cell types is driven by strong rhythmic synaptic input from presynaptic neurons that is blocked by CNQX. The recurrent synaptic activity may arise in a negative feedback loop between a bipolar cell and an amacrine cell that exhibits resonant behavior and oscillations in membrane potential when the normal balance between excitation and inhibition is disrupted by the absence of photoreceptor input.

  4. Spontaneous chylothorax complicating small cell lung cancer – Review of aetiology and diagnosis

    Directory of Open Access Journals (Sweden)

    S. Hanina

    2015-01-01

    Full Text Available We report the first case of spontaneous chylothorax complicating small cell lung cancer. A 52 year old female presented with exertional dyspnoea, left-sided chest and neck pain, and dysphagia. The chest X-ray on admission revealed a large left-sided pleural effusion. A subsequent CT chest showed a large anterior mediastinal mass with a left brachiocephalic and jugular vein thrombosis. The patient underwent medical thoracoscopy with chest drain insertion, which drained pleural fluid high in triglycerides, consistent with a chylothorax. Due to its uncommon nature, the management of chylothorax is not well defined. Alongside the case report, we provide a review of aetiology, mechanism and diagnosis with a brief summary of treatment options.

  5. Reduced L-Carnitine Transport in Aortic Endothelial Cells from Spontaneously Hypertensive Rats

    Science.gov (United States)

    Salsoso, Rocío; Guzmán-Gutiérrez, Enrique; Arroyo, Pablo; Salomón, Carlos; Zambrano, Sonia; Ruiz-Armenta, María Victoria; Blanca, Antonio Jesús; Pardo, Fabián; Leiva, Andrea; Mate, Alfonso; Sobrevia, Luis; Vázquez, Carmen María

    2014-01-01

    Impaired L-carnitine uptake correlates with higher blood pressure in adult men, and L-carnitine restores endothelial function in aortic rings from spontaneously hypertensive rat (SHR). Thus, endothelial dysfunction in hypertension could result from lower L-carnitine transport in this cell type. L-Carnitine transport is mainly mediated by novel organic cation transporters 1 (Octn1, Na+-independent) and 2 (Octn2, Na+-dependent); however, their kinetic properties and potential consequences in hypertension are unknown. We hypothesize that L-carnitine transport kinetic properties will be altered in aortic endothelium from spontaneously hypertensive rats (SHR). L-Carnitine transport was measured at different extracellular pH (pHo 5.5–8.5) in the absence or presence of sodium in rat aortic endothelial cells (RAECs) from non-hypertensive Wistar-Kyoto (WKY) rats and SHR. Octn1 and Octn2 mRNA relative expression was also determined. Dilation of endothelium-intact or denuded aortic rings in response to calcitonine gene related peptide (CGRP, 0.1–100 nmol/L) was measured (myography) in the absence or presence of L-carnitine. Total L-carnitine transport was lower in cells from SHR compared with WKY rats, an effect due to reduced Na+-dependent (Na+ dep) compared with Na+-independent (Na+ indep) transport components. Saturable L-carnitine transport kinetics show maximal velocity (V max), without changes in apparent K m for Na+ indep transport in SHR compared with WKY rats. Total and Na+ dep component of transport were increased, but Na+ indep transport was reduced by extracellular alkalization in WKY rats. However, alkalization reduced total and Na+ indep transport in cells from SHR. Octn2 mRNA was higher than Octn-1 mRNA expression in cells from both conditions. Dilation of artery rings in response to CGRP was reduced in vessels from SHR compared with WKY rats. CGRP effect was endothelium-dependent and restored by L-carnitine. All together these results suggest that reduced

  6. Crosstalk between type II NKT cells and T cells leads to spontaneous chronic inflammatory liver disease.

    Science.gov (United States)

    Weng, Xiufang; He, Ying; Visvabharathy, Lavanya; Liao, Chia-Min; Tan, Xiaosheng; Balakumar, Arjun; Wang, Chyung-Ru

    2017-10-01

    Natural killer T (NKT) cells are CD1d-restricted innate-like T cells that modulate innate and adaptive immune responses. Unlike the well-characterized invariant/type I NKT cells, type II NKT cells with a diverse T cell receptor repertoire are poorly understood. This study defines the pathogenic role of type II NKT cells in the etiology of chronic liver inflammation. Transgenic mice with the Lck promoter directing CD1d overexpression on T cells in Jα18 wild-type (Lck-CD1dTgJα18 + ; type I NKT cell sufficient) and Jα18-deficient (Lck-CD1dTgJα18 o , type I NKT cell deficient) mice were analyzed for liver pathology and crosstalk between type II NKT cells and conventional T cells. CD1d expression on T cells in peripheral blood samples and liver sections from autoimmune hepatitis patients and healthy individuals were also examined. Lck-CD1dTgJα18 o and Lck-CD1dTgJα18 + mice developed similar degrees of liver pathology resembling chronic autoimmune hepatitis in humans. Increased CD1d expression on T cells promoted the activation of type II NKT cells and other T cells. This resulted in T h 1-skewing and impaired T h 2 cytokine production in type II NKT cells. Dysfunction of type II NKT cells was accompanied by conventional T cell activation and pro-inflammatory cytokine production, leading to a hepatic T/B lymphocyte infiltration, elevated autoantibodies and hepatic injury in Lck-CD1dTg mice. A similar mechanism could be extended to humans as CD1d expression is upregulated on activated human T cells and increased presence of CD1d-expressing T cells was observed in autoimmune hepatitis patients. Our data reveals enhanced crosstalk between type II NKT cells and conventional T cells, leading to a T h 1-skewed inflammatory milieu, and consequently, to the development of chronic autoimmune liver disease. Lay summary: CD1d overexpression on T cells enhances crosstalk between type II NKT cells and T cells, resulting in their aberrant activation and leading to the

  7. Position-dependent patterning of spontaneous action potentials in immature cochlear inner hair cells.

    Science.gov (United States)

    Johnson, Stuart L; Eckrich, Tobias; Kuhn, Stephanie; Zampini, Valeria; Franz, Christoph; Ranatunga, Kishani M; Roberts, Terri P; Masetto, Sergio; Knipper, Marlies; Kros, Corné J; Marcotti, Walter

    2011-06-01

    Spontaneous action potential activity is crucial for mammalian sensory system development. In the auditory system, patterned firing activity has been observed in immature spiral ganglion and brain-stem neurons and is likely to depend on cochlear inner hair cell (IHC) action potentials. It remains uncertain whether spiking activity is intrinsic to developing IHCs and whether it shows patterning. We found that action potentials were intrinsically generated by immature IHCs of altricial rodents and that apical IHCs showed bursting activity as opposed to more sustained firing in basal cells. We show that the efferent neurotransmitter acetylcholine fine-tunes the IHC's resting membrane potential (V(m)), and as such is crucial for the bursting pattern in apical cells. Endogenous extracellular ATP also contributes to the V(m) of apical and basal IHCs by triggering small-conductance Ca(2+)-activated K(+) (SK2) channels. We propose that the difference in firing pattern along the cochlea instructs the tonotopic differentiation of IHCs and auditory pathway.

  8. Self-organized spatiotemporal patterns of PIP3 and PTEN during spontaneous cell polarization

    Science.gov (United States)

    Knoch, Fabian; Tarantola, Marco; Rappel, Wouter-Jan; Bodenschatz, Eberhard

    2014-03-01

    During spontaneous cell polarization of Dictyostelium discoideum cells, PIP3 (phosphatidylinositol (3,4,5)-triphoshpate) and PTEN (phosphatase tensin homolog) have been identified as key signaling molecules, which govern the process of polarization in a self-organized manner. Gerisch et al. have shown that randomly triggered excitable PIP3 waves regulate the anti-correlated PTEN concentration. Here we show that this requires a switch-like dynamics of the overall membrane bound PTEN concentration in combination with two species of PTEN differing in their dephosphorylation rates. A quantitative modeling with a coupled reaction-diffusion system shows excellent agreement with experimental results and predicts a ratio σ of dephosphorylation rates acting on PIP3 of σ ~ 80 - 100. Our quantitative analysis suggests that surface-attached cell membrane spanning PIP3 waves are necessary for resetting the global actin network. This is evidenced by the experimentally observed delay between polarization-cycles also quantitatively captured by our analysis. Max Planck Society and Center for Theoretical Biological Physics.

  9. Cell-free fetal DNA and cell-free total DNA levels in spontaneous abortion with fetal chromosomal aneuploidy.

    Directory of Open Access Journals (Sweden)

    Ji Hyae Lim

    Full Text Available Cell-free fetal DNA and cell-free total DNA in maternal circulation have been proposed as potential markers for noninvasive monitoring of the placental condition during the pregnancy. However, the correlation of and change in cell-free fetal DNA and cell-free total DNA in spontaneous abortion (SA with fetal chromosomal aneuploidy have not yet been reported. Therefore, we investigated cell-free fetal DNA and cell-free total DNA levels in SA women with fetal chromosomal aneuploidy.A nested case-control study was conducted with maternal plasma collected from 268 women in their first trimester of pregnancy. Subjects included 41 SA with normal fetal karyotype, 26 SA with fetal chromosomal aneuploidy, and 201 normal controls. The unmethylated PDE9A gene was used to measure the maternal plasma levels of cell-free fetal DNA. The GAPDH gene was used to measure the maternal plasma levels of cell-free total DNA. The diagnostic accuracy was measured using receiver-operating characteristic (ROC curves. Levels of cell-free fetal DNA and cell-free total DNA were significantly higher in both SA women with normal fetal karyotype and SA women with fetal chromosomal aneuploidy in comparison with the normal controls (P<0.001 in both. The correlation between cell-free fetal DNA and cell-free total DNA levels was stronger in the normal controls (r = 0.843, P<0.001 than in SA women with normal karyotype (r = 0.465, P = 0.002 and SA women with fetal chromosomal aneuploidy (r = 0.412, P = 0.037. The area under the ROC curve for cell-free fetal DNA and cell-free total DNA was 0.898 (95% CI, 0.852-0.945 and 0.939 (95% CI, 0.903-0.975, respectively.Significantly high levels of cell-free fetal DNA and cell-free total DNA were found in SA women with fetal chromosomal aneuploidy. Our findings suggest that cell-free fetal DNA and cell-free total DNA may be useful biomarkers for the prediction of SA with fetal chromosomal aneuploidy, regardless of fetal

  10. Establishment and characterization of a spontaneously immortalized trophoblast cell line (HPT-8) and its hepatitis B virus-expressing clone.

    Science.gov (United States)

    Zhang, Lei; Zhang, Weilu; Shao, Chen; Zhang, Jingxia; Men, Ke; Shao, Zhongjun; Yan, Yongping; Xu, Dezhong

    2011-08-01

    Most trophoblast cell lines currently available to study vertical transmission of hepatitis B virus (HBV) are immortalized by viral transformation. Our goal was to establish and characterize a spontaneously immortalized human first-trimester trophoblast cell line and its HBV-expressing clone. Chorionic villi of Asian human first-trimester placentae were digested with trypsin and collagenase I to obtain the primary trophoblast cell culture. A spontaneously immortalized trophoblast cell line (HPT-8) was analyzed by scanning and transmission electron microscopy, cell cycle analysis, immunohistochemistry and immunofluorescence. HPT-8 cells were stably transfected with the adr subtype of HBV (HPT-8-HBV) and characterized by PCR and enzyme-linked immunosorbent assay. We obtained a clonal derivative of a spontaneously immortalized primary cell clone (HPT-8). HPT-8 cells were epithelioid and polygonal, and formed multinucleate, giant cells. They exhibited microvilli, distinct desmosomes between adjacent cells, abundant endoplasm, lipid inclusions and glycogen granules, which are all characteristic of cytotrophoblasts. HPT-8 cells expressed cytokeratin 7, cytokeratin 18, vimentin, cluster of differentiation antigen 9, epidermal growth factor receptor, stromal cell-derived factor 1 and placental alkaline phosphatase. They secreted prolactin, estradiol, progesterone and hCG, and were positive for HLA-G, a marker of extravillous trophoblasts. HPT-8-HBV cells were positive for HBV relaxed-circular, covalently closed circular DNA and pre-S sequence. HPT-8-HBV cells also produced and secreted HBV surface antigen and HBV e antigen. We established a trophoblast cell line, HPT-8 and its HBV-expressing clone which could be valuable in exploring the mechanism of HBV viral integration in human trophoblasts during intrauterine infection.

  11. Tracking the embryonic stem cell transition from ground state pluripotency

    NARCIS (Netherlands)

    Kalkan, T.; Olova, N.; Roode, M.; Mulas, C.; Lee, H.J.; Nett, I.; Marks, H.; Walker, R.; Stunnenberg, H.; Lilley, K.S.; Nichols, J.; Reik, W.; Bertone, P.; Smith, A.

    2017-01-01

    Mouse embryonic stem (ES) cells are locked into self-renewal by shielding from inductive cues. Release from this ground state in minimal conditions offers a system for delineating developmental progression from naive pluripotency. Here we examined the initial transition process. The ES cell

  12. Nanodisperse transition metal electrodes (NTME) for electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Striebel, Kathryn A.; Wen, Shi-Jie

    1998-12-01

    Disclosed are transition metal electrodes for electrochemical cells using gel-state and solid-state polymers. The electrodes are suitable for use in primary and secondary cells. The electrodes (either negative electrode or positive electrode) are characterized by uniform dispersion of the transition metal at the nanoscale in the polymer. The transition metal moiety is structurally amorphous, so no capacity fade should occur due to lattice expansion/contraction mechanisms. The small grain size, amorphous structure and homogeneous distribution provide improved charge/discharge cycling performance, and a higher initial discharge rate capability. The cells can be cycled at high current densities, limited only by the electrolyte conductivity. A method of making the electrodes (positive and negative), and their usage in electrochemical cells are disclosed.

  13. General Information about Transitional Cell Cancer of the Renal Pelvis and Ureter

    Science.gov (United States)

    ... Transitional Cell Cancer of the Renal Pelvis and Ureter Treatment (PDQ®)–Patient Version General Information About Transitional Cell Cancer of the Renal Pelvis and Ureter Go to Health Professional Version Key Points Transitional ...

  14. Generation of an induced pluripotent stem cell line from chorionic villi of a Turner syndrome spontaneous abortion.

    Science.gov (United States)

    Parveen, Shagufta; Panicker, M M; Gupta, Pawan Kumar

    2017-03-01

    A major cause of spontaneous abortions is chromosomal abnormality of foetal cells. We report the generation of an induced pluripotent stem cell line from the fibroblasts isolated from chorionic villi of an early spontaneously aborted foetus with Turner syndrome. The Turner syndrome villus induced pluripotent stem cell line is transgene free, retains the original XO karyotype, expresses pluripotency markers and undergoes trilineage differentiation. This pluripotent stem cell model of Turner syndrome should serve as a tool to study the developmental abnormalities of foetus and placenta that lead to early embryo lethality and profound symptoms like infertility in 45 XO survivors. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Spontaneous cell polarization: Feedback control of Cdc42 GTPase breaks cellular symmetry.

    Science.gov (United States)

    Martin, Sophie G

    2015-11-01

    Spontaneous polarization without spatial cues, or symmetry breaking, is a fundamental problem of spatial organization in biological systems. This question has been extensively studied using yeast models, which revealed the central role of the small GTPase switch Cdc42. Active Cdc42-GTP forms a coherent patch at the cell cortex, thought to result from amplification of a small initial stochastic inhomogeneity through positive feedback mechanisms, which induces cell polarization. Here, I review and discuss the mechanisms of Cdc42 activity self-amplification and dynamic turnover. A robust Cdc42 patch is formed through the combined effects of Cdc42 activity promoting its own activation and active Cdc42-GTP displaying reduced membrane detachment and lateral diffusion compared to inactive Cdc42-GDP. I argue the role of the actin cytoskeleton in symmetry breaking is not primarily to transport Cdc42 to the active site. Finally, negative feedback and competition mechanisms serve to control the number of polarization sites. © 2015 WILEY Periodicals, Inc.

  16. Modeling self-organized spatio-temporal patterns of PIP₃ and PTEN during spontaneous cell polarization.

    Science.gov (United States)

    Knoch, Fabian; Tarantola, Marco; Bodenschatz, Eberhard; Rappel, Wouter-Jan

    2014-08-01

    During spontaneous cell polarization of Dictyostelium discoideum cells, phosphatidylinositol (3,4,5)-triphoshpate (PIP3) and PTEN (phosphatase tensin homolog) have been identified as key signaling molecules which govern the process of polarization in a self-organized manner. Recent experiments have quantified the spatio-temporal dynamics of these signaling components. Surprisingly, it was found that membrane-bound PTEN can be either in a high or low state, that PIP3 waves were initiated in areas lacking PTEN through an excitable mechanism, and that PIP3 was degraded even though the PTEN concentration remained low. Here we develop a reaction-diffusion model that aims to explain these experimental findings. Our model contains bistable dynamics for PTEN, excitable dynamics for PIP3, and postulates the existence of two species of PTEN with different dephosphorylation rates. We show that our model is able to produce results that are in good qualitative agreement with the experiments, suggesting that our reaction-diffusion model underlies the self-organized spatio-temporal patterns observed in experiments.

  17. Prognostic relevance of induced and spontaneous apoptosis of disseminated tumor cells in primary breast cancer patients

    International Nuclear Information System (INIS)

    Krawczyk, Natalia; Fehm, Tanja; Hartkopf, Andreas; Banys, Malgorzata; Meier-Stiegen, Franziska; Staebler, Annette; Wallwiener, Markus; Röhm, Carmen; Hoffmann, Juergen; Hahn, Markus

    2014-01-01

    An imbalance between cell proliferation and programmed cell death can result in tumor growth. Although most systemic cytotoxic agents induce apoptosis in tumor cells, a high apoptotic rate in primary breast cancer correlates with poor prognosis. The aim of this study was to investigate the incidence and the prognostic significance of apoptotic disseminated tumor cells (DTC) in the bone marrow (BM) of breast cancer patients who either underwent primary surgery or primary systemic chemotherapy (PST). A total of 383 primary breast cancer patients with viable DTC in the BM were included into this study. Eighty-five patients were initially treated with primary systemic chemotherapy whereas 298 patients underwent surgery first. Detection of apoptotic DTC were performed by immunocytochemistry using the M30 antibody which detects a neo-epitope expressed after caspase cleavage of cytokeratin 18 during early apoptosis. The median follow up was 44 months (range 10–88 months). Eighty-two of 298 (27%) primary operated patients and 41 of 85 (48%) patients treated with primary systemic systemic therapy had additional apoptotic DTC (M30 positive). In the neoadjuvant group M30-positive patients were less likely to suffer relapse than those without apoptotic DTC (7% vs. 23% of the events, p = 0.049). In contrast, the detection of apoptotic DTC in patients treated by primary surgery was significantly associated with poor overall survival (5% vs. 12% of the events, p = 0.008). Apoptotic DTC can be detected in breast cancer patients before and after systemic treatment. The presence of apoptotic DTC in patients with PST may be induced by the cytotoxic agents. Thus, both spontaneous and chemotherapy-induced apoptosis may have different prognostic significance

  18. Cell-free DNA, inflammation, and the initiation of spontaneous term labor.

    Science.gov (United States)

    Herrera, Christina A; Stoerker, Jay; Carlquist, John; Stoddard, Gregory J; Jackson, Marc; Esplin, Sean; Rose, Nancy C

    2017-11-01

    Hypomethylated cell-free DNA from senescent placental trophoblasts may be involved in the activation of the inflammatory cascade to initiate labor. To determine the changes in cell-free DNA concentrations, the methylation ratio, and inflammatory markers between women in labor at term vs women without labor. In this prospective cohort study, eligible participants carried a nonanomalous singleton fetus. Women with major medical comorbidity, preterm labor, progesterone use, aneuploidy, infectious disease, vaginal bleeding, abdominal trauma, or invasive procedures during the pregnancy were excluded. Maternal blood samples were collected at 28 weeks, 36 weeks, and at admission for delivery. Total cell-free DNA concentration, methylation ratio, and interleukin-6 were analyzed. The primary outcome was the difference in methylation ratio in women with labor vs without labor. Secondary outcomes included the longitudinal changes in these biomarkers corresponding to labor status. A total of 55 women were included; 20 presented in labor on admission and 35 presented without labor. Women in labor had significantly greater methylation ratio (P = .001) and interleukin-6 (P labor. After we controlled for body mass index and maternal age, methylation ratio (adjusted relative risk, 1.38; 95% confidence interval, 1.13 to 1.68) and interleukin-6 (adjusted relative risk, 1.12, 95% confidence interval, 1.07 to 1.17) remained greater in women presenting in labor. Total cell-free DNA was not significantly different in women with labor compared with women without. Longitudinally, total cell-free DNA (P labor, P = .002 without labor) and interleukin-6 (P labor, P = .01 without labor) increased significantly across gestation in both groups. The methylation ratio increased significantly in women with labor from 36 weeks to delivery (P = .02). Spontaneous labor at term is associated with a greater cell-free DNA methylation ratio and interleukin-6 compared with nonlabored controls. As

  19. Fibroblast growth factor-2 counteracts the effect of ciliary neurotrophic factor on spontaneous differentiation in adult hippocampal progenitor cells.

    Science.gov (United States)

    He, Zhili; Ding, Jun; Zhang, Jianfang; Liu, Ying; Gong, Chengxin; Sun, Shenggang; Chen, Honghui

    2012-12-01

    Neural stem/progenitor cells (NSCs) can spontaneously differentiate into neurons and glial cells in the absence of mitogen fibroblast growth factor-2 (FGF-2) or epidermal growth factor (EGF) in medium and the spontaneous differentiation of NSCs is mediated partially by endogenous ciliary neurotrophic factor (CNTF). This study examined the relationship of FGF-2 and CNTF in the spontaneous differentiation of adult hippocampal progenitor cells (AHPs). AHPs were cultured in the medium containing different concentration of FGF-2 (1-100 ng/mL). Western blotting and immunofluorescence staining were applied to detect the expression of the astrocytic marker GFAP, the neuronal marker Tuj1, the oligodendrocytic marker CNPase and, Nestin, the marker of AHPs. The expression of endogenous CNTF in AHPs at early (passage 4) and late stage (passage 22) was also measured by Western blotting. The results showed that FGF-2 increased the expression of Nestin, dramatically inhibited the expression of GFAP and Tuj1 and slightly suppressed the expression of CNPase. FGF-2 down-regulated the expression of endogenous CNTF in AHPs at both early (passage 4) and late stage (passage 22). These results suggested that FGF-2 could inhibit the spontaneous differentiation of cultured AHPs by negatively regulating the expression of endogenous CNTF in AHPs.

  20. Conditions of steady switching in phase-transition memory cells

    International Nuclear Information System (INIS)

    Popov, A. I.; Salnikov, S. M.; Anufriev, Yu. V.

    2015-01-01

    Three types of non-volatile memory cells of different designs based on phase transitions are developed and implemented. The effect of the design features of the cells and their active-region sizes on the switching characteristics and normal operation of the cells is considered as a whole. The causes of failure of the cells are analyzed from the obtained series of scanning electron images upon level-by-level etching of the samples. It is shown that the cell design is the most critical factor from the viewpoint of switching to the high-resistance state. The causes of this fact are analyzed and the criterion for providing the steady operation of cells of non-volatile memory based on phase transitions is formulated

  1. BC Transit Fuel Cell Bus Project Evaluation Results: Second Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Post, M.

    2014-09-01

    Second report evaluating a fuel cell electric bus (FCEB) demonstration led by British Columbia Transit (BC Transit) in Whistler, Canada. BC Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory to evaluate the buses in revenue service. NREL published its first report on the demonstration in February 2014. This report is an update to the previous report; it covers 3 full years of revenue service data on the buses from April 2011 through March 2014 and focuses on the final experiences and lessons learned.

  2. Chemokine CCL28 induces apoptosis of decidual stromal cells via binding CCR3/CCR10 in human spontaneous abortion.

    Science.gov (United States)

    Sun, Chan; Zhang, Yuan-Yuan; Tang, Chuan-Ling; Wang, Song-Cun; Piao, Hai-Lan; Tao, Yu; Zhu, Rui; Du, Mei-Rong; Li, Da-Jin

    2013-10-01

    Spontaneous abortion is the most common complication of pregnancy. Immune activation and the subsequent inflammation-induced tissue injury are often observed at the maternal-fetal interface as the final pathological assault in recurrent spontaneous abortion. However, the precise mechanisms responsible for spontaneous abortion involving inflammation are not fully understood. Chemokine CCL28 and its receptors CCR3 and CCR10 are important regulators in inflammatory process. Here, we examined the expression of CCL28 and its receptors in decidual stromal cells (DSCs) by immunochemistry and flow cytometry (FCM), and compared their expression level in DSCs from normal pregnancy versus spontaneous abortion, and their relationship to inflammatory cytokines production by DSCs. We further analyzed regulation of the pro-inflammatory cytokines on CCL28 expression in DSCs by real-time polymerase chain reaction, In-cell Western and FCM. The effects of CCL28-CCR3/CCR10 interaction on DSC apoptosis was investigated by Annexin V staining and FCM analysis or DAPI staining and nuclear morphology. Higher levels of the inflammatory cytokines interleukin (IL)-1β, IL-17A and tumor necrosis factor-α, and increased CCR3/CCR10 expression were observed in DSCs from spontaneous abortion compared with normal pregnancy. Treatment with inflammatory cytokines differently affected CCL28 and CCR3/CCR10 expression in DSCs. Human recombinant CCL28 promoted DSC apoptosis, which was eliminated by pretreatment with neutralizing antibodies against CCR3/CCR10 and CCL28. However, CCL28 did not affect DSC growth. These results suggest that the inflammation-promoted up-regulation of CCL28 and its receptors interaction in DSCs is involved in human spontaneous abortion via inducing DSC apoptosis.

  3. Endogenous WNT Signals Mediate BMP-Induced and Spontaneous Differentiation of Epiblast Stem Cells and Human Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Dorota Kurek

    2015-01-01

    Full Text Available Therapeutic application of human embryonic stem cells (hESCs requires precise control over their differentiation. However, spontaneous differentiation is prevalent, and growth factors induce multiple cell types; e.g., the mesoderm inducer BMP4 generates both mesoderm and trophoblast. Here we identify endogenous WNT signals as BMP targets that are required and sufficient for mesoderm induction, while trophoblast induction is WNT independent, enabling the exclusive differentiation toward either lineage. Furthermore, endogenous WNT signals induce loss of pluripotency in hESCs and their murine counterparts, epiblast stem cells (EpiSCs. WNT inhibition obviates the need to manually remove differentiated cells to maintain cultures and improves the efficiency of directed differentiation. In EpiSCs, WNT inhibition stabilizes a pregastrula epiblast state with novel characteristics, including the ability to contribute to blastocyst chimeras. Our findings show that endogenous WNT signals function as hidden mediators of growth factor-induced differentiation and play critical roles in the self-renewal of hESCs and EpiSCs.

  4. Ouabain binding to cultured vascular smooth muscle cells of the spontaneously hypertensive rat

    International Nuclear Information System (INIS)

    Hopp, L.; Khalil, F.; Tamura, H.; Kino, M.; Searle, B.M.; Tokushige, A.; Aviv, A.

    1986-01-01

    The binding of ouabain and K + to the Na + pump were analyzed in serially passed cultured vascular smooth muscle cells (VSMCs) originating from spontaneously hypertensive (SH) Wistar-Kyoto (WKY), and American Wistar (W) rats. The techniques have utilized analyses of displacement of [ 3 H]ouabain by both unlabeled ouabain and K + from specific binding sites on the VSMCs. The authors have found that 1) each of the VSMC preparations from the three rat strains appeared to demonstrate one population of specific ouabain receptors (Na + pumps); 2) the number of Na + pump units of both the SH and WKY rats was significantly lower than the number of Na + pump units of W rat VSMCs; 3) the equilibrium dissociation constant values (μM) for ouabain in VSMCs of SH and WKY rats were similar but were significantly higher than that of VSMCs derived from W rats; and 4) among the VSMCs originating from the three rat strains, the apparent equilibrium dissociation constant value for K + (mM) was the lowest in those of the SH rat compared with VSMCs of the WKY rat and W rat. Previous studies have demonstrated increased passive Na + and K + transport rate constants of SH rat VSMCs compared with either W or WKY rat cells. These findings suggest the possibility of higher permeabilities of the SH cells. They propose that the combined effect of a low number of Na + pump units with higher permeabilities to Na + and K + predisposes VSMCs of the SH rat to disturbances in their cellular ionic regulation. These genetic defects, if they occur in vivo, may lead to an increase in the vascular tone

  5. Surgical management for upper urinary tract transitional cell carcinoma.

    Science.gov (United States)

    Rai, Bhavan Prasad; Shelley, Mike; Coles, Bernadette; Biyani, Chandra S; El-Mokadem, Ismail; Nabi, Ghulam

    2011-04-13

    Upper tract transitional cell carcinomas (TCC) are uncommon and aggressive tumours. There are a number of surgical approaches to manage this condition including open radical nephroureterectomy and laparoscopic procedures. To determine the best surgical management option for upper tract transitional cell carcinoma. A sensitive search strategy was developed to identify relevant studies for inclusion in this review. The following databases were searched for randomised trials evaluating surgical approaches to the management of upper tract TCC: Medline EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, British Nursing Index, AMED, LILACS, Web of Science®, Scopus, Biosis, TRIP, Biomed Central, Dissertation Abstracts, and ISI Proceedings. The following criteria that were considered for this review.Types of studies - All randomised or quasi-randomised controlled trials comparing the various surgical methods and approaches for the management of localised upper tract transitional cell carcinoma. Types of participants - All adult patients with localised transitional cell carcinoma. Localised disease was defined as limited to the kidney or ureter with no gross regional lymph nodal enlargement on imaging. Types of interventions - Any surgical method or approach for managing localised upper tract transitional cell carcinoma. Types of outcome measures - Overall and cancer-specific survival were primary outcomes. Surgery-related morbidity. Quality of life and health economics outcomes were secondary outcomes. Two review authors examined the search results independently to identify trials for inclusion. We identified one randomised controlled trial that met our inclusion criteria. The trial showed that the laparoscopic approach had superior peri-operative outcomes compared to open approach. Laparoscopic was superior and statistically significant for blood loss (104 mL (millilitres) versus 430 mL, P management of upper tract transitional cell carcinoma

  6. Metastatic transitional cell carcinoma of the tibia radiologically mimicking osteosarcoma.

    LENUS (Irish Health Repository)

    Cunningham, Laurence Patrick

    2013-01-01

    We report a case of a 73-year-old lady with transitional cell carcinoma and no evidence of metastatic disease presenting with gradual weight loss, pretibial swelling and painful weightbearing. Investigations revealed a lesion of the right tibial diaphysis. The radiological and clinical appearance was that of primary osteosarcoma. Biopsy results revealed metastatic transitional cell carcinoma of the tibia. Intramedullary nailing was performed which relieved pain on weightbearing. The patient declined radiotherapy and was started on a palliative care regimen. This case illustrates the importance of histological diagnosis in the treatment of diaphyseal lesions.

  7. Characterization of a spontaneously generated murine retinal pigmented epithelium cell line; a model for in vitro experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ranaei Pirmardan, Ehsan [Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Soheili, Zahra-Soheila [Department of Molecular Medicine, National Institute of Genetic Engineering and Biotechnology, Tehran (Iran, Islamic Republic of); Samiei, Shahram [Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran (Iran, Islamic Republic of); Ahmadieh, Hamid [Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Mowla, Seyed Javad [Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Ezzati, Razie [Department of Molecular Medicine, National Institute of Genetic Engineering and Biotechnology, Tehran (Iran, Islamic Republic of); Naseri, Marzieh [Department of Molecular Medicine, Faculty of Advanced Technology, Iran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2016-10-01

    Retinal pigmented epithelium (RPE), the outermost layer of the retina, has a key role in maintaining retinal cells’ functions. Severity of the culture of RPE cells has exerted many limitations to both in vitro and in vivo studies and its therapeutic applications. Therefore, establishment of RPE cell lines with high proliferative potential can considerably improve study of RPE cell biology. Here we report generation of a spontaneously immortalized murine RPE cell line in primary mouse RPE cell culture. Founded colonized cells were picked up and expression of RPE and retinal progenitor cells’ (RPC) markers were studied using immunocytochemistry (ICC). Emerged cells cultured over 35 passages and population doubling times in different serum concentrations were calculated. We also investigated the ability of cells for becoming transfected by calcium-phosphate method and for becoming infected by adeno-associated virus serotype 2 (AAV2) using flow cytometry. Data showed that the cobblestone constituent cells expressed RPE65, cytokeratin and ZO1 and moreover several progenitor markers such as Pax6, Sox2, Nestin and Chx10. It revealed that, despite primary RPE cells, the newly emerged cells were easily transfectable and were highly infectable when compared with HEK293T cells. Our data indicated that the emerged mouse RPE cell line pretended RPC-like phenotype and also simultaneously expressed RPE markers. It would be a promising model for leading studies on RPE and RPC cells and substantially confirmed the great RPE plasticity and its invaluable potential in research studies. - Highlights: • Isolation of a spontaneously generated retinal pigmented epithelium cell line is reported. • The cells express some of the retinal progenitor cell markers in addition to the RPE markers. • The aforesaid cell line is highly transfecable and considerably infectable by AAV2. • These results confirm the great RPE plasticity and its invaluable potential in research studies.

  8. Spontaneous and field-induced phase transitions in TbFe.sub.5./sub.Al.sub.7./sub..

    Czech Academy of Sciences Publication Activity Database

    Gorbunov, Denis; Yasin, S.; Andreev, Alexander V.; Mushnikov, N. V.; Skourski, Y.; Zherlitsyn, S.; Wosnitza, J.

    2014-01-01

    Roč. 535, Sep (2014), 56-63 ISSN 0304-8853 R&D Projects: GA ČR GAP204/12/0150 Grant - others:AVČR(CZ) M100101203 Institutional support: RVO:68378271 Keywords : rare-earth intermetallics * ferrimagnetism * magnetic anisotropy * spin-reorientation transition * high magnetic fields * field-induced transition Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.970, year: 2014

  9. Novel spontaneous deletion of artemis exons 10 and 11 in mice leads to T- and B-cell deficiency.

    Directory of Open Access Journals (Sweden)

    Christian Barthels

    Full Text Available Here we describe a novel, spontaneous, 4035 basepairs long deletion in the DNA cross-link repair 1C (Dclre1c-locus in C57BL/6-mice, which leads to loss of exons 10 and 11 of the gene encoding for Artemis, a protein involved into V(D J-recombination of antigen receptors of T and B cells. While several spontaneous mutations of Artemis have been described to cause SCID in humans, in mice, only targeted deletions by knockout technology are known to cause the same phenotype so far. The deletion we observed causes a loss of Artemis function in the C57BL/6 strain and, consequently, the absence of T and B cells, in presence of normal numbers of NK cells and cells of the myeloid lineage. Thus, for the first time we present T(-B(-NK(+ severe combined immunodeficiency (SCID phenotype after spontaneously occurring modification of Artemis gene in mice. Our mouse model may serve as a valuable tool to study mechanisms as well as potential therapies of SCID in humans.

  10. Staghorn calculi and xanthogranulomatous pyelonephritis associated with transitional cell carcinoma

    Directory of Open Access Journals (Sweden)

    Chao-Wei Tseng

    2015-03-01

    Full Text Available Untreated staghorn calculi can cause xanthogranulomatous pyelonephritis (XGP, diminished renal function, and renal malignancy. Squamous cell carcinoma (SCC of the upper urinary tract is associated with kidney stones and chronic infection, but their association with transitional cell carcinoma (TCC has not been proven and has rarely been reported in literature. We present a rare case of staghorn calculi and XGP associated with TCC.

  11. Transitional cell carcinoma developing in a bladder diverticulum ...

    African Journals Online (AJOL)

    Computed tomography confirmed a left-sided narrow neck urinary bladder diverticulum, with wall thickening, in a 56-year-old man. These findings were initially detected on ultrasonographic investigation. Transitional cell carcinoma was confirmed histologically. There is an increased incidence of neoplastic transformation in ...

  12. Transitional Cell Carcinoma within a Portion of Inguinally Herniated Bladder

    Directory of Open Access Journals (Sweden)

    Matthew A. Uhlman

    2013-01-01

    Full Text Available Bladder herniation within the inguinal canal is a relatively uncommon finding. We report an even less-common occurrence of transitional cell carcinoma located within a portion of inguinally herniated bladder. Fewer than 20 reports exist in the literature describing this scenario.

  13. Leukemoid reaction associated with transitional cell carcinoma: A ...

    African Journals Online (AJOL)

    The goal of this article was to investigate the diagnosis, treatment and mechanisms of the leukemoid reaction (LKR) 14 15 associated with transitional cell carcinoma. A 64-year-old male patient presented with anuria. Color ultrasound imaging 15 16 revealed a large bladder tumor. Digital radiography and computerized ...

  14. Recurrence of isolated transitional cell carcinoma in an orthotopic ...

    African Journals Online (AJOL)

    A.M. Moeen

    2015-11-10

    Nov 10, 2015 ... rare with less than 10 cases reported to date [2,3]. We present the case of a female patient with isolated recurrent transitional cell carcinoma (TCC) in an ileal neobladder, diagnosed 18 months after radical cystectomy and modified Hautmann ileal bladder substitution. E-mail address: moeen3@yahoo.com.

  15. Management of transitional cell carcinoma of the urinary bladder at ...

    African Journals Online (AJOL)

    Management of transitional cell carcinoma of the urinary bladder at Kenyatta National Hospital, Nairobi. C G Waihenya, P N Mungai. Abstract. No Abstract. East African Medical Journal Vol. 83 (12) 2006: pp. 679-683. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL ...

  16. Spontaneous Rotational Inversion in Phycomyces

    KAUST Repository

    Goriely, Alain

    2011-03-01

    The filamentary fungus Phycomyces blakesleeanus undergoes a series of remarkable transitions during aerial growth. During what is known as the stagea IV growth phase, the fungus extends while rotating in a counterclockwise manner when viewed from above (stagea IVa) and then, while continuing to grow, spontaneously reverses to a clockwise rotation (stagea IVb). This phase lasts for 24-48Ah and is sometimes followed by yet another reversal (stageAIVc) before the overall growth ends. Here, we propose a continuum mechanical model of this entire process using nonlinear, anisotropic, elasticity and show how helical anisotropy associated with the cell wall structure can induce spontaneous rotation and, under appropriate circumstances, the observed reversal of rotational handedness. © 2011 American Physical Society.

  17. Total cystectomy for treatment of transitional cell carcinoma of the urethra and bladder trigone in a dog.

    Science.gov (United States)

    Boston, Sarah; Singh, Ameet

    2014-03-01

    To report total cystectomy with reimplantation of the ureters in the proximal aspect of the vagina. Case report. An 11-year-old female spayed Vizsla with spontaneously occurring transitional cell carcinoma of the urethra and bladder. After initial treatment for transitional cell carcinoma of the bladder trigone with urethral stent placement and chemotherapy, the dog developed urinary incontinence 2 months after stent placement. Eleven months after initial diagnosis, the dog developed pulmonary metastasis and local progression, leading to bilateral ureteral dilatation. After palliative radiation, total cystectomy was performed. The owners elected euthanasia 442 days after original presentation and 92 days after total cystectomy. Euthanasia was unrelated to the surgical procedure, but was related to the primary disease. Total cystectomy is a technically feasible procedure that should be considered for the treatment of bladder cancer in dogs. © Copyright 2014 by The American College of Veterinary Surgeons.

  18. Chronic hepatitis C virus infection triggers spontaneous differential expression of biosignatures associated with T cell exhaustion and apoptosis signaling in peripheral blood mononucleocytes.

    Science.gov (United States)

    Barathan, Muttiah; Gopal, Kaliappan; Mohamed, Rosmawati; Ellegård, Rada; Saeidi, Alireza; Vadivelu, Jamuna; Ansari, Abdul W; Rothan, Hussin A; Ravishankar Ram, M; Zandi, Keivan; Chang, Li Y; Vignesh, Ramachandran; Che, Karlhans F; Kamarulzaman, Adeeba; Velu, Vijayakumar; Larsson, Marie; Kamarul, Tunku; Shankar, Esaki M

    2015-04-01

    Persistent hepatitis C virus (HCV) infection appears to trigger the onset of immune exhaustion to potentially assist viral persistence in the host, eventually leading to hepatocellular carcinoma. The role of HCV on the spontaneous expression of markers suggestive of immune exhaustion and spontaneous apoptosis in immune cells of chronic HCV (CHC) disease largely remain elusive. We investigated the peripheral blood mononuclear cells of CHC patients to determine the spontaneous recruitment of cellular reactive oxygen species (cROS), immunoregulatory and exhaustion markers relative to healthy controls. Using a commercial QuantiGenePlex(®) 2.0 assay, we determined the spontaneous expression profile of 80 different pro- and anti-apoptotic genes in persistent HCV disease. Onset of spontaneous apoptosis significantly correlated with the up-regulation of cROS, indoleamine 2,3-dioxygenase (IDO), cyclooxygenase-2/prostaglandin H synthase (COX-2/PGHS), Foxp3, Dtx1, Blimp1, Lag3 and Cd160. Besides, spontaneous differential surface protein expression suggestive of T cell inhibition viz., TRAIL, TIM-3, PD-1 and BTLA on CD4+ and CD8+ T cells, and CTLA-4 on CD4+ T cells was also evident. Increased up-regulation of Tnf, Tp73, Casp14, Tnfrsf11b, Bik and Birc8 was observed, whereas FasLG, Fas, Ripk2, Casp3, Dapk1, Tnfrsf21, and Cflar were moderately up-regulated in HCV-infected subjects. Our observation suggests the spontaneous onset of apoptosis signaling and T cell exhaustion in chronic HCV disease.

  19. Changes of spontaneous miniature excitatory postsynaptic currents in rat hippocampal pyramidal cells induced by aniracetam.

    Science.gov (United States)

    Ghamari-Langroudi, M; Glavinovíc, M I

    1998-01-01

    Spontaneous miniature excitatory postsynaptic currents (mEPSCs) in rat hippocampal pyramidal neurones in slices (CA1 region) were recorded at 35-37 degrees C using the whole-cell patch-clamp technique before and after addition of aniracetam (1 mM) to determine how a partial blockade of desensitization alters the relationship between the amplitude (A) and kinetics of mEPSCs, and to evaluate the factors that determine their variability. The rise time (taur) and the time constant of decay of mEPSCs (taud) are essentially amplitude independent in control conditions, but become clearly amplitude dependent in the presence of aniracetam. The slopes of the best fitting lines to taud:A and taur:A data pairs were (+/- SD; ms/pA; n = 5): (1) (control) 0.07 +/- 0.02 and 0.008 +/- 0.003; (2) (aniracetam) 0.40 +/- 0.19 and 0.22 +/- 0.22. The amplitude-dependent prolongation of taud is explained by the concentration dependence of two related processes, the buffering of glutamate molecules by AMPA receptor channels, and the occupancy of the double-bound activatable states. A slower deactivation makes an amplitude-independent contribution. Desensitization reduces the amplitude dependence of taud by minimizing repeated openings of alpha-amino-3-hydroxy-methyl-isoxazole (AMPA) receptor channels. A greater amplitude dependence of taur probably involves both pre- and postsynaptic factors. The variability of A and taud values did not change significantly, but the factors underlying the variability of taud values were much affected. The greater amplitude dependence and the greater scatter about the best fitting lines to taud:A data pairs are approximately balanced by the greater mean values. The greater scatter of taud about the best fitting lines probably occurs because the saturation of AMPA receptors is not the same at different synapses with different numbers of AMPA receptors.

  20. Tracking the embryonic stem cell transition from ground state pluripotency.

    Science.gov (United States)

    Kalkan, Tüzer; Olova, Nelly; Roode, Mila; Mulas, Carla; Lee, Heather J; Nett, Isabelle; Marks, Hendrik; Walker, Rachael; Stunnenberg, Hendrik G; Lilley, Kathryn S; Nichols, Jennifer; Reik, Wolf; Bertone, Paul; Smith, Austin

    2017-04-01

    Mouse embryonic stem (ES) cells are locked into self-renewal by shielding from inductive cues. Release from this ground state in minimal conditions offers a system for delineating developmental progression from naïve pluripotency. Here, we examine the initial transition process. The ES cell population behaves asynchronously. We therefore exploited a short-half-life Rex1::GFP reporter to isolate cells either side of exit from naïve status. Extinction of ES cell identity in single cells is acute. It occurs only after near-complete elimination of naïve pluripotency factors, but precedes appearance of lineage specification markers. Cells newly departed from the ES cell state display features of early post-implantation epiblast and are distinct from primed epiblast. They also exhibit a genome-wide increase in DNA methylation, intermediate between early and late epiblast. These findings are consistent with the proposition that naïve cells transition to a distinct formative phase of pluripotency preparatory to lineage priming. © 2017. Published by The Company of Biologists Ltd.

  1. The order parameter of glass transition: Spontaneously delocalized nanoscale solitary wave with transverse ripplon-like soft wave

    Directory of Open Access Journals (Sweden)

    Jia Lin Wu

    2013-06-01

    Full Text Available In macromolecular self-avoiding random walk, movement of each chain-particle accompanies an instantaneous spin system with de Gennes n = 0 that provides extra energy, extra vacancy volume and relaxation time needed for chain-particles co-movement. Using these additional and instantaneous spin systems not only directly yields the same Brownian motion mode in glass transition (GT and reptation-tube model, but also proves that the entangled chain length corresponding to the Reynolds number in hydrodynamics and the inherent diffusion - delocalization mode of entangled chains, from frozen glass state to melt liquid state, is a chain-size solitary wave with transverse ripplon-like soft wave. Thus, the order parameter of GT is found. The various currently available GT theories, such as Static Replica, Random First-Order Transition, Potential Energy Landscape, Mode-Coupling and Nanoscale Heterogeneity, can be unified using the additional and instantaneous spin system. GT served as an inspiration and continues to serve as the paradigm in the universal random delocalization transitions from disorder to more disorder until turbulence.

  2. Spontaneous fertility in a male thalassemic patient after allogeneic hematopoietic cell transplantation

    Directory of Open Access Journals (Sweden)

    Nicoletta Iacovidou

    2017-11-01

    Full Text Available Patients with thalassemia major who received allogeneic hematopoietic cell transplantation are at increased risk of gonadal insufficiency and reduced fertility due to the toxicity of both the transfusional iron overload and the gonadotoxic effects of drugs used in the conditioning regimen. We present a case of an ex-thalassemic patient with spontaneous recovery of spermatogenesis that fathered a healthy, term male neonate. Maternal hemoglobin electrophoresis was within normal limits. At the age of 9.5 years the patient underwent hematopoietic cell transplantation. The conditioning therapy included busulfan (16 mg/kg and cyclophosphamide (200 mg/kg. No irradiation was administered. Thirty-two days after the hematopoietic cell transplantation the patient developed acute graft-versus-host disease needing long-term treatment with methylprednisolone, cyclosporine and immunoglobulin. Although consecutive semen analyses after the hematopoietic cell transplantation revealed azoospermia, the last semen analysis before conception, at the age of 33 years, was improved and normal follicle stimulating hormone (FSH, luteinizing hormone (LH and testosterone (Te levels were detected. The current pregnancy was the result of physical conception. In this case, it seems that thalassemia major along with the respective treatment prior to- and posthematopoietic cell transplantation did not irreparably impair spermatogenesis, probably due to the pre-pubertal time frame they were implemented.   对于接受异基因造血细胞移植的重型地中海贫血患者,由于输注性铁过载的毒性和预处理方案中所用药物性腺毒性作用这两方面的原因,都使其面临更大的性腺功能不全风险和更低的生育力。本文报道一例精子发生出现自然恢复的原重型地中海贫血患者,他成功孕育出一个健康的足月男婴。母体血红蛋白电泳在正常范围内。患者在9岁半时接受了造血细胞移植。预

  3. Computer algorithms for automated detection and analysis of local Ca2+ releases in spontaneously beating cardiac pacemaker cells.

    Directory of Open Access Journals (Sweden)

    Alexander V Maltsev

    Full Text Available Local Ca2+ Releases (LCRs are crucial events involved in cardiac pacemaker cell function. However, specific algorithms for automatic LCR detection and analysis have not been developed in live, spontaneously beating pacemaker cells. In the present study we measured LCRs using a high-speed 2D-camera in spontaneously contracting sinoatrial (SA node cells isolated from rabbit and guinea pig and developed a new algorithm capable of detecting and analyzing the LCRs spatially in two-dimensions, and in time. Our algorithm tracks points along the midline of the contracting cell. It uses these points as a coordinate system for affine transform, producing a transformed image series where the cell does not contract. Action potential-induced Ca2+ transients and LCRs were thereafter isolated from recording noise by applying a series of spatial filters. The LCR birth and death events were detected by a differential (frame-to-frame sensitivity algorithm applied to each pixel (cell location. An LCR was detected when its signal changes sufficiently quickly within a sufficiently large area. The LCR is considered to have died when its amplitude decays substantially, or when it merges into the rising whole cell Ca2+ transient. Ultimately, our algorithm provides major LCR parameters such as period, signal mass, duration, and propagation path area. As the LCRs propagate within live cells, the algorithm identifies splitting and merging behaviors, indicating the importance of locally propagating Ca2+-induced-Ca2+-release for the fate of LCRs and for generating a powerful ensemble Ca2+ signal. Thus, our new computer algorithms eliminate motion artifacts and detect 2D local spatiotemporal events from recording noise and global signals. While the algorithms were developed to detect LCRs in sinoatrial nodal cells, they have the potential to be used in other applications in biophysics and cell physiology, for example, to detect Ca2+ wavelets (abortive waves, sparks and

  4. A new Zero-Voltage-Transition PWM switching cell

    Energy Technology Data Exchange (ETDEWEB)

    Grigore, V. [Electronics and Telecommunications Faculty `Politebuica` University Bucharest (Romania); Kyyrae, J. [Helsinki University of Technology, Otaniemi (Finland): Institute of Intelligent Power Electronics

    1997-12-31

    In this paper a new Zero-Voltage-Transition (ZVT) PWM switching cell is presented. The proposed switching cell is composed of the normal hard-switched PWM cell (consisting of one active switch and one passive switch), plus an auxiliary circuit (consisting of one active switch and some reactive components). The auxiliary circuit is inactive during the ON and OFF intervals of the switches in the normal PWM switch. However, the transitions between the two states are controlled by the auxiliary circuit. Prior to turn-on, the voltage across the active switch in the PWM cell is forced to zero, thus the turn-on losses of the active switch are practically eliminated. At turn-off the auxiliary circuit behaves like a non-dissipative passive snubber reducing the turn-off losses to a great extent. Zero-Voltage-Transition switching technique almost eliminates switching losses. The active switch operates under ZVT conditions, the passive switch (diode) has a controlled reverse recovery, and the switch in the auxiliary circuit operates under Zero-Current-Switching (ZCS) conditions. (orig.) 6 refs.

  5. Spontaneous squamous cell carcinoma of the tongue and multiple bronchioloalveolar carcinomas in a Virginia opossum (Didelphis virginiana).

    Science.gov (United States)

    Kim, D Y; Mitchell, M A; De las Heras, M; Taylor, H W; Cho, D-Y

    2002-01-01

    Two primary tumours, squamous cell carcinoma of the tongue and multiple bronchioloalveolar carcinomas, were diagnosed in a Virginia opossum (Didelphis virginiana). Two oral masses were located in the right ventrolateral surface of the tongue, near the frenulum, and the lungs contained multiple, widely distributed, nodular masses. Microscopically, the oral masses were composed of invasive cords of pleomorphic, polyhedral cells, typical of squamous cells. The multiple pulmonary masses consisted of non-ciliated, cuboidal, columnar, or occasionally polyhedral cells arranged in an alveolar pattern with multifocal areas of necrosis. This is the first report of spontaneous oropharyngeal squamous cell carcinoma in the Virginia opossum. However, multiple pulmonary adenomas have been reported previously in this species, the lesions being similar to those in sheep pulmonary adenomatosis (jaagsiekte). In the present study, immunohistochemical examination of the pulmonary tumours with a rabbit polyclonal antiserum to jaagsiekte retroviral capsid protein proved negative. Copyright Harcourt Publishers Ltd.

  6. Somatic cell hybrids between human lymphoma lines. II. Spontaneous and induced patterns of the Epstein-Barr virus (EBV) cycle.

    Science.gov (United States)

    Klein, G; Clements, G; Zeuthen, J; Westman, A

    1976-06-15

    The regulation of spontaneous, IUDR-induced and P3HR-1 virus-induced EA and VCA production patterns was studied in two new somatic hybrids between human lymphoma lines. The hybrid 8A was derived from the crossing of the non-producer Raji with the spontaneous producer Daudi line. The second hybrid, 83, was produced by the fusion of Raji with the EBV-genome-negative B-lymphoma line, BJAB. The studies suggest the following EBV regulation patterns: (1) the spontaneous production of EA and VCA appears to be regulated by controls that differ from the regulators of P3HR-1 virus-induced or IUDR-induced EA synthesis. While spontaneous producer status was dominant over non-producer status, the level of EA inducibility was set by one of the parental cells, Raji ATG, and could either raise (in the previously studied Raji/Namalwa hybrid, cf Nyormoi et al. 1973) or depress (in Raji/Daudi) the level of relative EA inducibility found in the partner cell. (2) Although EA production is a prerequisite for VCA synthesis, the latter is under its own restriction mechanisms, quite independent of those that regulate the level of EA synthesis. (3) Inducibility of EA synthesis by P3HR-1 virus and by IUDR appear to be under the influence of at least partially identical controls. (4) EBV-negative lymphoma cells, exemplified by BJAB, may exert a "complementation" effect on the EA inducibility of their EBV-positive fusion partner, in spite of their own restrictivity against virus-induced EA synthesis. In more general terms, it is obvious that the EBV cycle is under the influence of multiple regulatory mechanisms in the human lymphoid cell. Depending on the parental cell and viral genomes that are allowed to interact, somatic cell hybrids may display a variety of patterns. At this time, cell hybridization is one of the few pathways that permit an approach to this complex and completely unknown world.

  7. Aggressive natural killer-cell leukemia with jaundice and spontaneous splenic rupture: a case report and review of the literature.

    Science.gov (United States)

    Gao, Li-min; Liu, Wei-ping; Yang, Qun-pei; Li, Hui-fang; Chen, Jun-jie; Tang, Yuan; Zou, Yan; Liao, Dian-Ying; Liu, Yan-mei; Zhao, Sha

    2013-03-11

    Aggressive natural killer cell leukemia/lymphoma (ANKL) is a rare aggressive form of NK-cell neoplasm. We report an uncommon case of 36-year-old male who showed jaundice and spontaneous splenic rupture. The diagnosis was established by the biopsy of liver and spleen. The monomorphous medium-size neoplastic cells infiltrated into portal areas and sinus of liver as well as the cords and sinus of the spleen. Necrosis, mitotic figures and significant apoptosis could be seen easily. These neoplastic cells demonstrated a typical immunophenotype of CD3ε+, CD56+, CD16+, Granzyme B+, TIA-1+. T-cell receptor γ (TCR-γ) gene rearrangement analysis showed germline configuration and the result of in situ hybridization for Epstein-Barr virus-encoded RNA (EBER-ISH) was positive. The patient has undergone an aggressive clinical course and died of multi-organ function failure 14 days later after admission. To the best of our knowledge, this is the first case of ANKL with spontaneous splenic rupture, and we should pay more attention to recognize it. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2048154883890867.

  8. Subcutaneous Transitional Cell Cancer After Percutaneous Nephrolithotomy: A Case Report

    Directory of Open Access Journals (Sweden)

    Lokman Ižrkilata

    2013-10-01

    Full Text Available Transitional cell carcinomas of the upper urinary tract are rare but, highly predisposing to tumoral seeding. Percutaneous lithotripsy (PNL recently has expanded the therapeutic choices for patients with kidney stones and gained popularity by urologic surgeons. Although unusual, renal collecting system tumours may be encountered during PNL. We present and discuss the clinical course of a 48 years old male patient who underwent PNL surgery for kidney stone in whom transitional cell carcinoma in the renal collecting system obscured by stone left undiagnosed. Three months later following PNL he admitted with a bulge on lumbar region. Excisional biopsy revealed carcinoma and therefore, he was directed to chemoradiotherapy and died 21 months later. Renal collecting system tumors undiagnosed during surgery may progress and demonstrate local invasion in a short period of time. Therefore, we recommend to take more caution during any percutaneous access and to exclude the possible existence of tumor.

  9. Long-Term Quiescent Fibroblast Cells Transit into Senescence

    Science.gov (United States)

    Marthandan, Shiva; Priebe, Steffen; Hemmerich, Peter; Klement, Karolin; Diekmann, Stephan

    2014-01-01

    Cellular senescence is described to be a consequence of telomere erosion during the replicative life span of primary human cells. Quiescence should therefore not contribute to cellular aging but rather extend lifespan. Here we tested this hypothesis and demonstrate that cultured long-term quiescent human fibroblasts transit into senescence due to similar cellular mechanisms with similar dynamics and with a similar maximum life span as proliferating controls, even under physiological oxygen conditions. Both, long-term quiescent and senescent fibroblasts almost completely fail to undergo apoptosis. The transition of long-term quiescent fibroblasts into senescence is also independent of HES1 which protects short-term quiescent cells from becoming senescent. Most significantly, DNA damage accumulates during senescence as well as during long-term quiescence at physiological oxygen levels. We suggest that telomere-independent, potentially maintenance driven gradual induction of cellular senescence during quiescence is a counterbalance to tumor development. PMID:25531649

  10. Transitional Cell Carcinoma of Kidney- Report of a Rare Case

    Directory of Open Access Journals (Sweden)

    Priyesh Halgaonkar

    2015-01-01

    Full Text Available Hematuria is a common presentation in the surgical outpatient department. The most common causes being urinary tract infection or renal calculi that causes hematuria. Few of them are being diagnosed as Renal or Bladder mass. Transitional cell carcinoma affecting urogenital tract accounts for 5-10% of the primary renal malignancies which is relatively rare. Here we report such rare case in an elderly female who presented with painless hematuria.

  11. Isolated Meningeal Recurrence of Transitional Cell Carcinoma of the Bladder

    Directory of Open Access Journals (Sweden)

    Catherine Butchart

    2010-06-01

    Full Text Available Meningeal carcinomatosis occurs in 1–18% of patients with solid tumours, most commonly carcinomas of the breast and lung or melanomas. There are relatively few reports of meningeal carcinomatosis in transitional cell carcinoma of the bladder. Isolated meningeal recurrence is particularly uncommon, and we present an unusual case of this in a 58-year-old man. The case was further complicated by the somewhat atypical presentation with a confirmed ischaemic stroke. The patient died one month after presentation.

  12. Effects of harman and norharman on spontaneous and ultraviolet light-induced mutagenesis in cultured Chinese hamster cells

    International Nuclear Information System (INIS)

    Chang, C.C.; Castellazzi, M.; Glover, T.W.; Trosko, J.E.

    1978-01-01

    Nontoxic concentrations of harman and norharman were tested in cultured Chinese hamster cells for their effects on DNA repair and mutagenesis. The following effects of harman were observed: (a) the survival of ultraviolet light- or x-ray-damaged cells was reduced; (b) the ultraviolet light-induced unscheduled DNA synthesis was slightly inhibited; and (c) the frequency of spontaneous or ultraviolet light-induced ouabain-resistant (ouar) or 6-thioguanine-resistant (6-TGr) mutations was reduced. Furthermore, the effect of harman on survival and mutagenesis was greater than that of norharman and was detected primarily in treatments in which cells were exposed to harman immediately following ultraviolet light irradiation. Our data clearly indicate that harman decreases the capacity to repair DNA damage and fix mutations in Chinese hamster cells, possibly because of the intercalation properties of this compound

  13. Spontaneous food allergy in Was-/-mice occurs independent of FcεRI-mediated mast cell activation.

    Science.gov (United States)

    Lexmond, W S; Goettel, J A; Sallis, B F; McCann, K; Rings, E H H M; Jensen-Jarolim, E; Nurko, S; Snapper, S B; Fiebiger, E

    2017-12-01

    Food allergies are a growing health problem, and the development of therapies that prevent disease onset is limited by the lack of adjuvant-free experimental animal models. We compared allergic sensitization in patients with food allergy or Wiskott-Aldrich syndrome (WAS) and defined whether spontaneous disease in Was -/- mice recapitulates the pathology of a conventional disease model and/or human food allergy. Comparative ImmunoCAP ISAC microarray was performed in patients with food allergy or WAS. Spontaneous food allergy in Was -/- mice was compared to an adjuvant-based model in wild-type mice (WT-OVA/alum). Intestinal and systemic anaphylaxis was assessed, and the role of the high-affinity IgE Fc receptor (FcεRI) in allergic sensitization was evaluated using Was -/- Fcer1a -/- mice. Polysensitization to food was detected in both WAS and food-allergic patients which was recapitulated in the Was -/- model. Oral administration of ovalbumin (OVA) in Was -/- mice induced low titers of OVA-specific IgE compared to the WT-OVA/alum model. Irrespectively, 79% of Was -/- mice developed allergic diarrhea following oral OVA challenge. Systemic anaphylaxis occurred in Was -/- mice (95%) with a mortality rate >50%. Spontaneous sensitization and intestinal allergy occurred independent of FcεRI expression on mast cells (MCs) and basophils. Was -/- mice provide a model of food allergy with the advantage of mimicking polysensitization and low food-antigen IgE titers as observed in humans with clinical food allergy. This model will facilitate studies on aberrant immune responses during spontaneous disease development. Our results imply that therapeutic targeting of the IgE/FcεRI activation cascade will not affect sensitization to food. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  14. A new Zero-Current-Transition PWM switching cell

    Energy Technology Data Exchange (ETDEWEB)

    Grigore, V. [Electronics and Telecommunications Faculty, `Politechnica` University Bucharest (Romania); Kyyrae, J. [Helsinki University of Technology, Otaniemi (Finland): Institute of Intelligent Power Electronics

    1997-12-31

    In this paper a new Zero-Current-Transition (ZCT) PWM switching cell is presented. The proposed switching cell is composed of the normal hard-switched PWM cell (consisting of one active switch and one passive switch), plus as auxiliary circuit. The auxiliary circuit is inactive during the ON ad OFF intervals of the switches in the normal PWM switch. The transitions between the two states are controlled by the auxiliary circuit. Prior to turn-off, the current through the active switch in the PWM cell is forced to zero, thus the turn-off losses of the active switch are practically eliminated. At turn-on the auxiliary circuit slows down the growing rate of the current through the main switch. Thus, turn-on losses are also very much reduced. The active switch operates under ZCT conditions, the passive switch (diode) has a controlled reverse recovery, while the switch in the auxiliary circuit operates under Zero-Current-Switching (ZCS) conditions. (orig.) 3 refs.

  15. Role of spinal glial cells in bee-toxin-induced spontaneous pain, hyperalgesia, and inflammation

    OpenAIRE

    Yao LU; Jian-xiu WANG; Zhi-guo YAO; Hui-sheng CHEN

    2012-01-01

    Objective To observe the effects of intrathecal injection of fluorocitrate, a glial metabolism inhibitor, on bee-toxin-induced spontaneous pain, hyperalgesia and inflammatory response. Methods Forty adult male SD rats with intrathecal catheterization were randomly divided into five groups (8 each): (1) bee-toxin alone group; (2) vehicle (solvent) group; (3) low dose (1nmol) fluorocitrate group; (4) middle dose (10nmol) fluorocitrate group; (5) high dose (50nmol) fluorocitrate group. After the...

  16. DNA Amplification by Breakage/Fusion/Bridge Cycles Initiated by Spontaneous Telomere Loss in a Human Cancer Cell Line

    Directory of Open Access Journals (Sweden)

    Anthony W.l. Lo

    2002-01-01

    Full Text Available The development of genomic instability is an important step in generatingthe multiple genetic changes required for cancer. One consequence of genomic instability is the overexpression of oncogenes due to gene amplification. One mechanism for gene amplification is the breakagelfusionlbridge (B/F/Bcyclethatinvolvesthe repeated fusion and breakage of chromosomes following the loss of a telomere. B/F/B cycles have been associated with low-copy gene amplification in human cancer cells, and have been proposed to be an initiating event in high-copy gene amplification. We have found that spontaneous telomere loss on a marker chromosome 16 in a human tumor cell line results in sister chromatid fusion and prolonged periods of chromosome instability. The high rate of anaphase bridges involving chromosome 16 demonstrates that this instability results from B/F/B cycles. The amplification of subtelomeric DNA on the marker chromosome provides conclusive evidence that B/F/B cycles initiated by spontaneous telomere loss are a mechanism for gene amplification in human cancer cells.

  17. CERDEC Fuel Cell Team: Military Transitions for Soldier Fuel Cells

    Science.gov (United States)

    2008-10-27

    Continued Ardica: 20W Wearable PEMFC operating on Chemical Hydrides Spectrum Brands w/ Rayovac: Hydrogen Generators and Alkaline Fuel Cells for AA...running on JP-8 / diesel fuel & 250W RMFC Aspen : 5kWe integrated desulfurizer and JP-8 / diesel fuel processor Altex: 2-kWe integrated desulfurizer...and JP-8 / diesel fuel processor Precision Combustion : 5-kWt integrated desulfurizer and JP-8 and diesel fuel processor Customers Partners Army

  18. Spontaneous confocal Raman microscopy--a tool to study the uptake of nanoparticles and carbon nanotubes into cells

    Science.gov (United States)

    Romero, Gabriela; Rojas, Elena; Estrela-Lopis, Irina; Donath, Edwin; Moya, Sergio Enrique

    2011-06-01

    Confocal Raman microscopy as a label-free technique was applied to study the uptake and internalization of poly(lactide- co-glycolide) (PLGA) nanoparticles (NPs) and carbon nanotubes (CNTs) into hepatocarcinoma human HepG2 cells. Spontaneous confocal Raman spectra was recorded from the cells exposed to oxidized CNTs and to PLGA NPs. The Raman spectra showed bands arising from the cellular environment: lipids, proteins, nucleic acids, as well as bands characteristic for either PLGA NPs or CNTs. The simultaneous generation of Raman bands from the cell and nanomaterials from the same spot proves internalization, and also indicates the cellular region, where the nanomaterial is located. For PLGA NPs, it was found that they preferentially co-localized with lipid bodies, while the oxidized CNTs are located in the cytoplasm.

  19. Proteomics research on muscle-invasive bladder transitional cell carcinoma

    Directory of Open Access Journals (Sweden)

    Cao Yan

    2011-06-01

    Full Text Available Abstract Background Aimed to facilitate candidate biomarkers selection and improve network-based multi-target therapy, we perform comparative proteomics research on muscle-invasive bladder transitional cell carcinoma. Laser capture microdissection was used to harvest purified muscle-invasive bladder cancer cells and normal urothelial cells from 4 paired samples. Two-dimensional liquid chromatography tandem mass spectrometry was used to identify the proteome expression profile. The differential proteins were further analyzed using bioinformatics tools and compared with the published literature. Results A total of 885/890 proteins commonly appeared in 4 paired samples. 295/337 of the 488/493 proteins that specific expressed in tumor/normal cells own gene ontology (GO cellular component annotation. Compared with the entire list of the international protein index (IPI, there are 42/45 GO terms exhibited as enriched and 9/5 exhibited as depleted, respectively. Several pathways exhibit significantly changes between cancer and normal cells, mainly including spliceosome, endocytosis, oxidative phosphorylation, etc. Finally, descriptive statistics show that the PI Distribution of candidate biomarkers have certain regularity. Conclusions The present study identified the proteome expression profile of muscle-invasive bladder cancer cells and normal urothelial cells, providing information for subcellular pattern research of cancer and offer candidate proteins for biomarker panel and network-based multi-target therapy.

  20. Effect of in vitro irradiation and cell cycle-inhibitory drugs on the spontaneous human IgE synthesis in vitro

    International Nuclear Information System (INIS)

    Del Prete, G.F.; Vercelli, D.; Tiri, A.; Maggi, E.; Rossi, O.; Romagnani, S.; Ricci, M.

    1987-01-01

    The in vitro effects of radiation, diterpine forskolin (FK), and hydrocortisone (HC) on the in vitro spontaneous IgE synthesis by peripheral blood B-lymphocytes from atopic patients were investigated. Without affecting cell viability, in vitro irradiation inhibited in a dose-dependent fashion de novo IgE synthesis in vitro by B cells from all patients examined with a mean 40% reduction of in vitro IgE product after treatment with 100 rads. In contrast, the in vitro IgE production by the U266 myeloma cell line was unaffected, even by irradiation with 1600 rads. The addition to B cell cultures from atopic patients of FK consistently resulted in a dose-dependent inhibition of the spontaneous IgE production in vitro. The addition to cultures of 10(-5) and 10(-6) molar concentrations of HC was also usually inhibitory, whereas lower HC concentrations were uneffective or even enhanced the spontaneous in vitro IgE synthesis. When 10(-6) molar concentrations of both HC and FK were combined in culture, a summation inhibitory effect on the spontaneous IgE synthesis was observed. In contrast, neither FK nor HC had inhibitory effect on the in vitro spontaneous IgE synthesis by the U266 myeloma cell line. The spontaneous in vitro IgE synthesis by B cells from patients with Hodgkin's disease, demonstrating high levels of serum IgE, was strongly reduced or virtually abolished after patients underwent total nodal irradiation to prevent the spread of the disease. In addition, the in vitro spontaneous IgE synthesis by B cells from atopic patients was markedly decreased or abolished by in vivo administration of betamethasone

  1. Dentate gyrus progenitor cell proliferation after the onset of spontaneous seizures in the tetanus toxin model of temporal lobe epilepsy.

    Science.gov (United States)

    Jiruska, Premysl; Shtaya, Anan B Y; Bodansky, David M S; Chang, Wei-Chih; Gray, William P; Jefferys, John G R

    2013-06-01

    Temporal lobe epilepsy alters adult neurogenesis. Existing experimental evidence is mainly from chronic models induced by an initial prolonged status epilepticus associated with substantial cell death. In these models, neurogenesis increases after status epilepticus. To test whether status epilepticus is necessary for this increase, we examined precursor cell proliferation and neurogenesis after the onset of spontaneous seizures in a model of temporal lobe epilepsy induced by unilateral intrahippocampal injection of tetanus toxin, which does not cause status or, in most cases, detectable neuronal loss. We found a 4.5 times increase in BrdU labeling (estimating precursor cells proliferating during the 2nd week after injection of toxin and surviving at least up to 7days) in dentate gyri of both injected and contralateral hippocampi of epileptic rats. Radiotelemetry revealed that the rats experienced 112±24 seizures, lasting 88±11s each, over a period of 8.6±1.3days from the first electrographic seizure. On the first day of seizures, their duration was a median of 103s, and the median interictal period was 23min, confirming the absence of experimentally defined status epilepticus. The total increase in cell proliferation/survival was due to significant population expansions of: radial glial-like precursor cells (type I; 7.2×), non-radial type II/III neural precursors in the dentate gyrus stem cell niche (5.6×), and doublecortin-expressing neuroblasts (5.1×). We conclude that repeated spontaneous brief temporal lobe seizures are sufficient to promote increased hippocampal neurogenesis in the absence of status epilepticus. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Epithelial to mesenchymal transition in human endocrine islet cells.

    Directory of Open Access Journals (Sweden)

    José Luis Moreno-Amador

    Full Text Available β-cells undergo an epithelial to mesenchymal transition (EMT when expanded in monolayer culture and give rise to highly proliferative mesenchymal cells that retain the potential to re-differentiate into insulin-producing cells.To investigate whether EMT takes place in the endocrine non-β cells of human islets.Human islets isolated from 12 multiorgan donors were dissociated into single cells, purified by magnetic cell sorting, and cultured in monolayer.Co-expression of insulin and the mesenchymal marker vimentin was identified within the first passage (p1 and increased subsequently (insulin+vimentin+ 7.2±6% at p1; 43±15% at p4. The endocrine non-β-cells did also co-express vimentin (glucagon+vimentin+ 59±1.5% and 93±6%, somatostatin+vimentin+ 16±9.4% and 90±10% at p1 and p4 respectively; PP+vimentin+ 74±14% at p1; 88±12% at p2. The percentage of cells expressing only endocrine markers was progressively reduced (0.6±0.2% insulin+, 0.2±0.1% glucagon+, and 0.3±0.2% somatostatin+ cells at p4, and 0.7±0.3% PP+ cells at p2. Changes in gene expression were also indicated of EMT, with reduced expression of endocrine markers and the epithelial marker CDH-1 (p<0.01, and increased expression of mesenchymal markers (CDH-2, SNAI2, ZEB1, ZEB2, VIM, NT5E and ACTA2; p<0.05. Treatment with the EMT inhibitor A83-01 significantly reduced the percentage of co-expressing cells and preserved the expression of endocrine markers.In adult human islets, all four endocrine islet cell types undergo EMT when islet cells are expanded in monolayer conditions. The presence of EMT in all islet endocrine cells could be relevant to design of strategies aiming to re-differentiate the expanded islet cells towards a β-cell phenotype.

  3. Fingolimod induces BAFF and expands circulating transitional B cells without activating memory B cells and plasma cells in multiple sclerosis.

    Science.gov (United States)

    Miyazaki, Yusei; Niino, Masaaki; Takahashi, Eri; Suzuki, Masako; Mizuno, Masanori; Hisahara, Shin; Fukazawa, Toshiyuki; Amino, Itaru; Nakano, Fumihito; Nakamura, Masakazu; Akimoto, Sachiko; Minami, Naoya; Fujiki, Naoto; Doi, Shizuki; Shimohama, Shun; Terayama, Yasuo; Kikuchi, Seiji

    2018-02-01

    Patients with multiple sclerosis (MS) who are treated with fingolimod have an increased proportion of transitional B cells in the circulation, but the underlying mechanism is not known. We hypothesized that B cell-activating factor of the tumor necrosis factor family (BAFF) is involved in the process. Compared with healthy controls and untreated MS patients, fingolimod-treated MS patients had significantly higher serum concentrations of BAFF, which positively correlated with the proportions and the absolute numbers of transitional B cells in blood. Despite the elevated concentrations of BAFF in fingolimod-treated MS patients, serum levels of soluble transmembrane activator and calcium-modulating cyclophilin ligand interactor, and B cell maturation antigen were not elevated. Our results show that fingolimod induces BAFF in the circulation and expands transitional B cells, but does not activate memory B cells or plasma cells in MS, which is favorable for the treatment of this disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Speeding the transition: Designing a fuel-cell hypercar

    Energy Technology Data Exchange (ETDEWEB)

    Williams, B.D.; Moore, T.C.; Lovins, A.B. [Rocky Mountain Inst., Snowmass, CO (United States). Hypercar Center

    1997-12-31

    A rapid transformation now underway in automotive technology could accelerate the transition to transportation powered by fuel cells. Ultralight, advanced-composite, low-drag, hybrid-electric hypercars--using combustion engines--could be three- to fourfold more efficient and one or two orders of magnitude cleaner than today`s cars, yet equally safe, sporty, desirable, and (probably) affordable. Further, important manufacturing advantages--including low tooling and equipment costs, greater mechanical simplicity, autobody parts consolidation, shorter product cycles, and reduced assembly effort and space--permit a free-market commercialization strategy. This paper discusses a conceptual hypercar powered by a proton-exchange-membrane fuel cell (PEMFC). It outlines the implications of platform physics and component selection for the vehicle`s mass budget and performance. The high fuel-to-traction conversion efficiency of the hypercar platform could help automakers overcome the Achilles` heel of hydrogen-powered vehicles: onboard storage. Moreover, because hypercars would require significantly less tractive power, and even less fuel-cell power, they could adopt fuel cells earlier, before fuel cells` specific cost, mass, and volume have fully matured. In the meantime, commercialization in buildings can help prepare fuel cells for hypercars. The promising performance of hydrogen-fueled PEMFC hypercars suggests important opportunities in infrastructure development for direct-hydrogen vehicles.

  5. Direct transplantation of mesenchymal stem cells into the knee joints of Hartley strain guinea pigs with spontaneous osteoarthritis.

    Science.gov (United States)

    Sato, Mitsuhiko; Uchida, Kenzo; Nakajima, Hideaki; Miyazaki, Tsuyoshi; Guerrero, Alexander Rodriguez; Watanabe, Shuji; Roberts, Sally; Baba, Hisatoshi

    2012-02-07

    Mesenchymal stem cells (MSCs) can differentiate into various connective tissue cells. Several techniques have been used for the clinical application of MSCs in articular cartilage repair; however, there are many issues associated with the selection of the scaffold material, including its ability to support cell viability and differentiation and its retention and degradation in situ. The application of MSCs via a scaffold also requires a technically demanding surgical procedure. The aim of this study was to test the outcome of intra-articular transplantation of mesenchymal stem cells suspended in hyaluronic acid (HA) in the knee joints of Hartley strain guinea pigs with spontaneous osteoarthritis (OA). Commercially available human MSCs were cultured, labeled with carboxyfluorescein diacetate succinimidyl ester (CFDA-SE), suspended in either PBS or HA, and injected into the knee joints of 7-month-old animals. The control animals were injected with either PBS or HA alone. The animals were sacrificed at 1, 3, and 5 weeks post transplantation, the knee joints harvested, and fluorescent microscopic analysis was performed. Histological and immunohistochemical analysis were performed at 5 weeks post transplantation. At 5 weeks post transplantation, partial cartilage repair was noted in the HA-MSC group but not in the other groups. Examination of CFDA-SE-labeled cells demonstrated migration, differentiation, and proliferation of MSC in the HA-MSC group. There was strong immunostaining for type II collagen around both residual chondrocytes and transplanted MSCs in the OA cartilage. This scaffold-free and technically undemanding technique appears to result in the regeneration of articular cartilage in the spontaneous OA animal model. Although further examination of the long-term effects of transplantation is necessary, the findings suggest that intra-articular injection of HA-MSC mixture is potentially beneficial for OA.

  6. Novel pancreatic cancer cell lines derived from genetically engineered mouse models of spontaneous pancreatic adenocarcinoma: applications in diagnosis and therapy.

    Directory of Open Access Journals (Sweden)

    María P Torres

    Full Text Available Pancreatic cancer (PC remains one of the most lethal human malignancies with poor prognosis. Despite all advances in preclinical research, there have not been significant translation of novel therapies into the clinics. The development of genetically engineered mouse (GEM models that produce spontaneous pancreatic adenocarcinoma (PDAC have increased our understanding of the pathogenesis of the disease. Although these PDAC mouse models are ideal for studying potential therapies and specific genetic mutations, there is a need for developing syngeneic cell lines from these models. In this study, we describe the successful establishment and characterization of three cell lines derived from two (PDAC mouse models. The cell line UN-KC-6141 was derived from a pancreatic tumor of a Kras(G12D;Pdx1-Cre (KC mouse at 50 weeks of age, whereas UN-KPC-960 and UN-KPC-961 cell lines were derived from pancreatic tumors of Kras(G12D;Trp53(R172H;Pdx1-Cre (KPC mice at 17 weeks of age. The cancer mutations of these parent mice carried over to the daughter cell lines (i.e. Kras(G12D mutation was observed in all three cell lines while Trp53 mutation was observed only in KPC cell lines. The cell lines showed typical cobblestone epithelial morphology in culture, and unlike the previously established mouse PDAC cell line Panc02, expressed the ductal marker CK19. Furthermore, these cell lines expressed the epithelial-mesenchymal markers E-cadherin and N-cadherin, and also, Muc1 and Muc4 mucins. In addition, these cell lines were resistant to the chemotherapeutic drug Gemcitabine. Their implantation in vivo produced subcutaneous as well as tumors in the pancreas (orthotopic. The genetic mutations in these cell lines mimic the genetic compendium of human PDAC, which make them valuable models with a high potential of translational relevance for examining diagnostic markers and therapeutic drugs.

  7. Spontaneous development of hepatocellular carcinoma with cancer stem cell properties in PR-SET7-deficient livers

    Science.gov (United States)

    Nikolaou, Kostas C; Moulos, Panagiotis; Chalepakis, George; Hatzis, Pantelis; Oda, Hisanobu; Reinberg, Danny; Talianidis, Iannis

    2015-01-01

    PR-SET7-mediated histone 4 lysine 20 methylation has been implicated in mitotic condensation, DNA damage response and replication licensing. Here, we show that PR-SET7 function in the liver is pivotal for maintaining genome integrity. Hepatocyte-specific deletion of PR-SET7 in mouse embryos resulted in G2 phase arrest followed by massive cell death and defect in liver organogenesis. Inactivation at postnatal stages caused cell duplication-dependent hepatocyte necrosis, accompanied by inflammation, fibrosis and compensatory growth induction of neighboring hepatocytes and resident ductal progenitor cells. Prolonged necrotic regenerative cycles coupled with oncogenic STAT3 activation led to the spontaneous development of hepatic tumors composed of cells with cancer stem cell characteristics. These include a capacity to self-renew in culture or in xenografts and the ability to differentiate to phenotypically distinct hepatic cells. Hepatocellular carcinoma in PR-SET7-deficient mice displays a cancer stem cell gene signature specified by the co-expression of ductal progenitor markers and oncofetal genes. PMID:25515659

  8. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2010

    Science.gov (United States)

    2010-11-11

    This past year has been one of transition for the introduction of fuel cell transit buses. The existing generation of fuel cell buses from Van Hool and UTC Power has continued to operate in service at three transit agencies. At the same time, a new g...

  9. Emergence of p53 mutant cisplatin-resistant ovarian carcinoma cells following drug exposure: spontaneously mutant selection.

    Science.gov (United States)

    Righetti, S C; Perego, P; Corna, E; Pierotti, M A; Zunino, F

    1999-07-01

    We have previously shown that p53 mutations are associated with cisplatin resistance in ovarian carcinoma IGROV-1/Pt 1 cells. The relationship between p53 status and the development of resistance has not been completely elucidated; in particular, the biological mechanisms behind the acquired drug-resistant p53-mutant phenotype were not clearly explained. Thus, in this study, we investigated whether the p53 mutations found in IGROV-1/Pt 1 cells (270 and 282 codons) resulted from selection, under the selective pressure of the cytotoxic treatment, of a spontaneously mutant cell population preexistent in the cisplatin-sensitive parental cell line (IGROV-1) or were induced by drug (genotoxic) treatment. For this purpose, an allele-specific PCR approach was used. Primers carrying the desired mutations (T-->A codon 270, C-->T codon 282) in the 3' terminus, and the corresponding wild-type primers were used to amplify genomic DNA from the original IGROV-1 cell line used to select the mutant IGROV-1/Pt 1. To increase sensitivity, we hybridized blots of the PCRs with the radiolabeled PCR fragment from IGROV-1/Pt 1. Amplification was obtained for IGROV-1 DNA with the mutated allele-specific primers, indicating the preexistence of a mutated population in the IGROV-1 cell line. Titration experiments suggested that the frequency of the mutated alleles was PCR analysis of the IGROV-1/Pt 0.1 cells, which are less resistant to cisplatin than IGROV-1/Pt 1 cells and which carry both mutant and wild-type p53 alleles with a wild-type predominance, suggested a progressive selection of the mutant population by cisplatin treatment. This is the first observation that indicates that a subpopulation of p53 mutant cells can occasionally be selected by cisplatin treatment. Thus, considering the susceptibility to spontaneous mutations of the p53 gene in advanced ovarian carcinoma, the selection process resulting in emergence of p53 mutant tumors is a possible origin of resistance of ovarian

  10. CD4+ T cells spontaneously producing human immunodeficiency virus type I in breast milk from women with or without antiretroviral drugs

    Directory of Open Access Journals (Sweden)

    Rubbo Pierre-Alain

    2011-05-01

    Full Text Available Abstract Background Transmission of human immunodeficiency virus type 1 (HIV-1 through breast-feeding may involve both cell-free and cell-associated virus. This latter viral reservoir remains, however, to be fully explored. CD4+ T cell-associated virus production in breast milk was therefore investigated. Methods The ex vivo spontaneous production of HIV-1 antigen and HIV-1 RNA by CD4+ T cells was measured in paired blood and breast milk samples from 15 HIV-1 infected women treated or not with antiretroviral drugs. Spontaneous antigen secreting cells (HIV-1-AgSCs from breast milk and blood were enumerated by an ELISpot assay, and cell-associated HIV-1 RNA was quantified by real-time PCR in supernatants of CD4+ T cells cultured for 18 hours without addition of polyclonal activators. Results Among the CD4+ T cells present in breast milk, memory cells expressing high levels of cell-surface activation markers were predominant. Spontaneous HIV-1-AgSCs were detected and enumerated in the breast milk of all 15 women, with a median number of 13.0 and 9.5 HIV-1- AgSCs/106 CD4+ T cells in aviremic (n = 7 and viremic (n = 8 women, respectively. Cell- associated HIV-1 RNA was detected in cell-free supernatants from 4/7 aviremic and 5/8 viremic individuals at median levels of 190 and 245 copies/ml, respectively. Conclusions Activated CD4+ T cells producing HIV-1 are detected in the breast milk of untreated individuals as well as those receiving highly active antiretroviral therapy. This finding strongly suggests that HIV-1 replication occurs in latently infected CD4+ T cells that, upon spontaneous activation, revert to productively infected cells. These cells might be responsible for a residual breast milk transmission despite maternal highly active antiretroviral therapy.

  11. CD4+ T cells spontaneously producing human immunodeficiency virus type I in breast milk from women with or without antiretroviral drugs.

    Science.gov (United States)

    Valea, Diane; Tuaillon, Edouard; Al Tabaa, Yassine; Rouet, François; Rubbo, Pierre-Alain; Meda, Nicolas; Foulongne, Vincent; Bollore, Karine; Nagot, Nicolas; Van de Perre, Philippe; Vendrell, Jean-Pierre

    2011-05-13

    Transmission of human immunodeficiency virus type 1 (HIV-1) through breast-feeding may involve both cell-free and cell-associated virus. This latter viral reservoir remains, however, to be fully explored. CD4+ T cell-associated virus production in breast milk was therefore investigated. The ex vivo spontaneous production of HIV-1 antigen and HIV-1 RNA by CD4+ T cells was measured in paired blood and breast milk samples from 15 HIV-1 infected women treated or not with antiretroviral drugs. Spontaneous antigen secreting cells (HIV-1-AgSCs) from breast milk and blood were enumerated by an ELISpot assay, and cell-associated HIV-1 RNA was quantified by real-time PCR in supernatants of CD4+ T cells cultured for 18 hours without addition of polyclonal activators. Among the CD4+ T cells present in breast milk, memory cells expressing high levels of cell-surface activation markers were predominant. Spontaneous HIV-1-AgSCs were detected and enumerated in the breast milk of all 15 women, with a median number of 13.0 and 9.5 HIV-1- AgSCs/106 CD4+ T cells in aviremic (n = 7) and viremic (n = 8) women, respectively. Cell- associated HIV-1 RNA was detected in cell-free supernatants from 4/7 aviremic and 5/8 viremic individuals at median levels of 190 and 245 copies/ml, respectively. Activated CD4+ T cells producing HIV-1 are detected in the breast milk of untreated individuals as well as those receiving highly active antiretroviral therapy. This finding strongly suggests that HIV-1 replication occurs in latently infected CD4+ T cells that, upon spontaneous activation, revert to productively infected cells. These cells might be responsible for a residual breast milk transmission despite maternal highly active antiretroviral therapy.

  12. Spontaneous pneumothorax

    Directory of Open Access Journals (Sweden)

    Davari R

    1996-07-01

    Full Text Available A case with bilateral spontaneous pneumothorax was presented. Etiology, mechanism, and treatment were discussed on the review of literature. Spontaneous Pneumothorax is a clinical entity resulting from a sudden non traumatic rupture of the lung. Biach reported in 1880 that 78% of 916 patients with spontaneous pneumothorax had tuberculosis. Kjergaard emphasized 1932 the primary importance of subpleural bleb disease. Currently the clinical spectrum of spontaneous pneumothorax seems to have entered a third era with the recognition of the interstitial lung disease and AIDS as a significant etiology. Standard treatment is including: observation, thoracocentesis, tube thoracostomy. Chemical pleurodesis, bullectomy or wedge resection of lung with pleural abrasion and occasionally pleurectomy. Little information has been reported regarding the efficacy of such treatment in spontaneous pneumothorax secondary to non bleb disease

  13. Age-related changes in immunoreactivity for dopamine β-hydroxylase in carotid body glomus cells in spontaneously hypertensive rats.

    Science.gov (United States)

    Kato, Kouki; Fushuku, Seigo; Yamamoto, Yoshio

    2017-07-01

    The purpose of this study was to investigate immunoreactivity for dopamine β-hydroxylase (DBH) and tyrosine hydroxylase (TH) in carotid body (CB) glomus cells in spontaneously hypertensive rats (SHR/Izm) at 4 (prehypertensive stage), 8 (early stage of developmental hypertension), 12 (later stage of developmental hypertension), and 16weeks of age (established hypertensive stage). Age-matched Wistar Kyoto rats (WKY/Izm) were used as controls. Staining properties for TH were similar between both strains at each age. Regarding DBH immunostaining, although some glomus cells showed intense DBH immunoreactivity at 4weeks of age, these cells were rarely observed at 8, 12, and 16weeks of age in WKY/Izm. In SHR/Izm, intense DBH immunoreactivity was observed in some glomus cells at 4weeks of age, these cells were also observed at 8 and 12weeks of age, and their number increased at 16weeks of age. An image analysis showed that the percentage of DBH-immunopositive glomus cells in WKY/Izm was approximately 30% at 4weeks of age and significantly decreased to approximately 10% at 8, 12, and 16weeks of age (pcells was similar in both strains at 4weeks of age, but became significantly lower in WKY/Izm and higher in SHR/Izm with increase in age (pcells plays an important role in the regulation of neurotransmission between CB and afferent nerves during developmental hypertension. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Transitional cell carcinoma involving the ductus deferens in a dog.

    Science.gov (United States)

    Guerin, Vincent J; 't Hooft, Krista W Visser; L'Eplattenier, Henry F; Petite, Audrey F

    2012-02-15

    A 12-year-old neutered male Springer Spaniel was referred with a 1-year history of recurring urinary tract infections. Repeated treatment with appropriate antimicrobials selected on the basis of bacterial culture and antimicrobial susceptibility results would result in clinical improvement, but recurrence of clinical signs was observed within days after discontinuation of treatment. Ultrasound examination revealed a tubular, fluid-filled structure dorsal to the bladder that extended from the midlevel of the bladder to the cranial pole of the prostate. Mineralized foci within a heterogeneous prostatic parenchyma were also noted. Dilation of the right ductus deferens (DD) was observed during exploratory laparotomy. Both DD were surgically removed, and the prostate was biopsied. The histopathological diagnosis was transitional cell carcinoma involving the right DD and the prostate. The dog was treated with meloxicam (0.1 mg/kg [0.05 mg/lb], p.o., q 24 h) for 9 months after diagnosis before being euthanized. Because the normal DD is rarely visualized during abdominal ultrasonography in dogs, identification of a tubular, fluid-filled structure dorsal to the bladder may indicate an abnormal DD. Transitional cell carcinoma of the DD should be included in the differential diagnoses of affected patients examined for clinical signs involving the urinary tract.

  15. Cell reprogramming modelled as transitions in a hierarchy of cell cycles

    Science.gov (United States)

    Hannam, Ryan; Annibale, Alessia; Kühn, Reimer

    2017-10-01

    We construct a model of cell reprogramming (the conversion of fully differentiated cells to a state of pluripotency, known as induced pluripotent stem cells, or iPSCs) which builds on key elements of cell biology viz. cell cycles and cell lineages. Although reprogramming has been demonstrated experimentally, much of the underlying processes governing cell fate decisions remain unknown. This work aims to bridge this gap by modelling cell types as a set of hierarchically related dynamical attractors representing cell cycles. Stages of the cell cycle are characterised by the configuration of gene expression levels, and reprogramming corresponds to triggering transitions between such configurations. Two mechanisms were found for reprogramming in a two level hierarchy: cycle specific perturbations and a noise induced switching. The former corresponds to a directed perturbation that induces a transition into a cycle-state of a different cell type in the potency hierarchy (mainly a stem cell) whilst the latter is a priori undirected and could be induced, e.g. by a (stochastic) change in the cellular environment. These reprogramming protocols were found to be effective in large regimes of the parameter space and make specific predictions concerning reprogramming dynamics which are broadly in line with experimental findings.

  16. Spontaneous presence of FOXO3-specific T cells in cancer patients

    DEFF Research Database (Denmark)

    Larsen, Stine Kiaer; Ahmad, Shamaila Munir; Idorn, Manja

    2014-01-01

    may naturally serve as a target antigen for tumor-reactive T cells as it is frequently over-expressed in cancer cells. In addition, expression of FOXO3 plays a critical role in immunosuppression mediated by tumor-associated dendritic cells (TADCs). Indeed, FOXO3-specific cytotoxic T lymphocytes (CTLs......) were able to specifically recognize and kill both FOXO3-expressing cancer cells as well as dendritic cells. Thus, FOXO3 was processed and presented by HLA-A2 on the cell surface of both immune cells and cancer cells. As FOXO3 programs TADCs to become tolerogenic, FOXO3 signaling thereby comprises...... a significant immunosuppressive mechanism, such that FOXO3 targeting by means of specific T cells is an attractive clinical therapy to boost anticancer immunity. In addition, the natural occurrence of FOXO3-specific CTLs in the periphery suggests that these T cells hold a function in the complex network...

  17. In vivo single cell analysis reveals Gata2 dynamics in cells transitioning to hematopoietic fate.

    Science.gov (United States)

    Eich, Christina; Arlt, Jochen; Vink, Chris S; Solaimani Kartalaei, Parham; Kaimakis, Polynikis; Mariani, Samanta A; van der Linden, Reinier; van Cappellen, Wiggert A; Dzierzak, Elaine

    2018-01-02

    Cell fate is established through coordinated gene expression programs in individual cells. Regulatory networks that include the Gata2 transcription factor play central roles in hematopoietic fate establishment. Although Gata2 is essential to the embryonic development and function of hematopoietic stem cells that form the adult hierarchy, little is known about the in vivo expression dynamics of Gata2 in single cells. Here, we examine Gata2 expression in single aortic cells as they establish hematopoietic fate in Gata2Venus mouse embryos. Time-lapse imaging reveals rapid pulsatile level changes in Gata2 reporter expression in cells undergoing endothelial-to-hematopoietic transition. Moreover, Gata2 reporter pulsatile expression is dramatically altered in Gata2 +/- aortic cells, which undergo fewer transitions and are reduced in hematopoietic potential. Our novel finding of dynamic pulsatile expression of Gata2 suggests a highly unstable genetic state in single cells concomitant with their transition to hematopoietic fate. This reinforces the notion that threshold levels of Gata2 influence fate establishment and has implications for transcription factor-related hematologic dysfunctions. © 2018 Eich et al.

  18. The spontaneous ataxic mouse mutant tippy is characterized by a novel Purkinje cell morphogenesis and degeneration phenotype

    Science.gov (United States)

    Shih, Evelyn K.; Sekerková, Gabriella; Ohtsuki, Gen; Aldinger, Kimberly A.; Chizhikov, Victor V.; Hansel, Christian; Mugnaini, Enrico; Millen, Kathleen J.

    2015-01-01

    This study represents the first detailed analysis of the spontaneous neurological mouse mutant, tippy, uncovering its unique cerebellar phenotype. Homozygous tippy mutant mice are small, ataxic and die around weaning. Although the cerebellum shows grossly normal foliation, tippy mutants display a complex cerebellar Purkinje cell phenotype consisting of abnormal dendritic branching with immature spine features and patchy, non-apoptotic cell death that is associated with widespread dystrophy and degeneration of the Purkinje cell axons throughout the white matter, the cerebellar nuclei and the vestibular nuclei. Moderate anatomical abnormalities of climbing fiber innervation of tippy mutant Purkinje cells were not associated with changes in climbing fiber-EPSC amplitudes. However, decreased ESPC amplitudes were observed in response to parallel fiber stimulation and correlated well with anatomical evidence for patchy dark cell degeneration of Purkinje cell dendrites in the molecular layer. The data suggest that the Purkinje neurons are a primary target of the tippy mutation. Furthermore, we hypothesize that the Purkinje cell axonal pathology together with disruptions in the balance of climbing fiber and parallel fiber Purkinje cell input in the cerebellar cortex underlie the ataxic phenotype in these mice. The constellation of Purkinje cell dendritic malformation and degeneration phenotypes in tippy mutants is unique and has not been reported in any other neurologic mutant. Fine mapping of the tippy mutation to a 2.1MB region of distal chromosome 9, which does not encompass any gene previously implicated in cerebellar development or neuronal degeneration, confirms that the tippy mutation identifies novel biology and gene function. PMID:25626522

  19. High-Efficiency Fullerene Solar Cells Enabled by a Spontaneously Formed Mesostructured CuSCN-Nanowire Heterointerface

    KAUST Repository

    Sit, Wai-Yu

    2018-02-02

    Fullerenes and their derivatives are widely used as electron acceptors in bulk-heterojunction organic solar cells as they combine high electron mobility with good solubility and miscibility with relevant semiconducting polymers. However, studies on the use of fullerenes as the sole photogeneration and charge-carrier material are scarce. Here, a new type of solution-processed small-molecule solar cell based on the two most commonly used methanofullerenes, namely [6,6]-phenyl-C61-butyric acid methyl ester (PC60BM) and [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM), as the light absorbing materials, is reported. First, it is shown that both fullerene derivatives exhibit excellent ambipolar charge transport with balanced hole and electron mobilities. When the two derivatives are spin-coated over the wide bandgap p-type semiconductor copper (I) thiocyanate (CuSCN), cells with power conversion efficiency (PCE) of ≈1%, are obtained. Blending the CuSCN with PC70BM is shown to increase the performance further yielding cells with an open-circuit voltage of ≈0.93 V and a PCE of 5.4%. Microstructural analysis reveals that the key to this success is the spontaneous formation of a unique mesostructured p–n-like heterointerface between CuSCN and PC70BM. The findings pave the way to an exciting new class of single photoactive material based solar cells.

  20. Spontaneous ATM Gene Reversion in A-T iPSC to Produce an Isogenic Cell Line

    Directory of Open Access Journals (Sweden)

    Lucy Lin

    2015-12-01

    Full Text Available A spontaneously reverted iPSC line was identified from an A-T subject with heterozygous ATM truncation mutations. The reverted iPSC line expressed ATM protein and was capable of radiation-induced phosphorylation of CHK2 and H2A.X. Genome-wide SNP analysis confirmed a match to source T cells and also to a distinct, non-reverted iPSC line from the same subject. Rearranged T cell receptor sequences predict that the iPSC culture originated as several independently reprogrammed cells that resolved into a single major clone, suggesting that gene correction likely occurred early in the reprogramming process. Gene expression analysis comparing ATM−/− iPSC lines to unrelated ATM+/− cells identifies a large number of differences, but comparing only the isogenic pair of A-T iPSC lines reveals that the primary pathway affected by loss of ATM is a diminished expression of p53-related mRNAs. Gene reversion in culture, although likely a rare event, provided a novel, reverted cell line for studying ATM function.

  1. A third measure-metastable state in the dynamics of spontaneous shape change in healthy human's white cells.

    Directory of Open Access Journals (Sweden)

    Karen A Selz

    2011-04-01

    Full Text Available Human polymorphonuclear leucocytes, PMN, are highly motile cells with average 12-15 µm diameters and prominent, loboid nuclei. They are produced in the bone marrow, are essential for host defense, and are the most populous of white blood cell types. PMN also participate in acute and chronic inflammatory processes, in the regulation of the immune response, in angiogenesis, and interact with tumors. To accommodate these varied functions, their behavior is adaptive, but still definable in terms of a set of behavioral states. PMN morphodynamics have generally involved a non-equilibrium stationary, spheroid Idling state that transitions to an activated, ellipsoid translocating state in response to chemical signals. These two behavioral shape-states, spheroid and ellipsoid, are generally recognized as making up the vocabulary of a healthy PMN. A third, "random" state has occasionally been reported as associated with disease states. I have observed this third, Treadmilling state, in PMN from healthy subjects, the cells demonstrating metastable dynamical behaviors known to anticipate phase transitions in mathematical, physical, and biological systems. For this study, human PMN were microscopically imaged and analyzed as single living cells. I used a microscope with a novel high aperture, cardioid annular condenser with better than 100 nanometer resolution of simultaneous, mixed dark field and intrinsic fluorescent images to record shape changes in 189 living PMNs. Relative radial roundness, R(t, served as a computable order parameter. Comparison of R(t series of 10 cells in the Idling and 10 in the Treadmilling state reveals the robustness of the "random" appearing Treadmilling state, and the emergence of behaviors observed in the neighborhood of global state transitions, including increased correlation length and variance (divergence, sudden jumps, mixed phases, bimodality, power spectral scaling and temporal slowing. Wavelet transformation of an R

  2. Silk-Fibroin and Graphene Oxide Composites Promote Human Periodontal Ligament Stem Cell Spontaneous Differentiation into Osteo/Cementoblast-Like Cells.

    Science.gov (United States)

    Vera-Sánchez, Mar; Aznar-Cervantes, Salvador; Jover, Eva; García-Bernal, David; Oñate-Sánchez, Ricardo E; Hernández-Romero, Diana; Moraleda, Jose M; Collado-González, Mar; Rodríguez-Lozano, Francisco Javier; Cenis, Jose Luis

    2016-11-15

    Graphene represents one of the most interesting additions to the tissue engineering toolbox. Novel graphene-based composites are required to improve the beneficial graphene properties in terms of tridimensional polymeric structure, conferring a higher mechanical strength and favoring the differentiation of human mesenchymal stem cells. Here, we have demonstrated in a wide range of composite combinations, the successful use of graphene and silk-fibroin constructs for future bioengineering applications in the field of clinical regenerative dentistry using human periodontal ligament stem cells. Our results provide exciting new data for the development of suitable scaffolds that allow good cell engrafting, preservation of cell viability and proliferation, promotion of spontaneous osteoblastic differentiation, and importantly, stimulation of a higher cementum physiological synthesis than using other different available biomaterials.

  3. Mn++-stimulated 3H-inositol incorporation in cultured vascular smooth muscle cells: deficiency in cells from spontaneously hypertensive rats

    International Nuclear Information System (INIS)

    Buck, S.H.; Nabika, T.; Lovenberg, W.

    1985-01-01

    Incubation of cultured dissociated aortic smooth muscle cells from Wistar-Kyoto rats (WKY) with Mn++ resulted in a 10-fold stimulation of 3 H-myo-inositol incorporation into membrane phospholipids. The stimulation was temperature and energy dependent. The Mn++ EC50 was 1 mM and maximum stimulation occurred at 10 mM Mn++. Other cations were ineffective. In cells from spontaneously hypertensive rats (SHR), the Mn++ EC50 was unchanged whereas the maximum stimulation of 3 H-inositol incorporation was reduced by 50% compared to cells from parallel WKY cultures. These results suggest that in SHR cultured vascular smooth muscle cells there is a deficiency in an enzymatic process mediating exchange of free inositol with the headgroup inositol of membrane phosphatidylinositol

  4. CT and MRI Findings of a Transitional Cell Carcinoma Case Located at Sino-nasopharyngeal Junction

    Directory of Open Access Journals (Sweden)

    Erkan Gokce

    2015-09-01

    Full Text Available Nonkeratinizing carcinoma (transitional cell carcinoma accounts for 1 to 20% of carcinomas of the sinonasal tract. Most of transitional cell carcinomas develop de novo, but a few may arise from preexisting inverted papillomas. Although histopathological findings of transitional cell carcinomas are well documented in the literature, detailed information on imaging findings is scarce. In the present study, CT and MRI findings of a de novo developed transitional cell carcinoma located at sino-nasopharyngeal junction are presented. [J Contemp Med 2015; 5(3.000: 199-202

  5. Flow cytometric applications of tumor biology: prospects and pitfalls. [Applications in study of spontaneous dog tumors and in drug and radiation effects on cultured V79 cells

    Energy Technology Data Exchange (ETDEWEB)

    Raju, M.R.; Johnson, T.S.; Tokita, N.; Gillette, E.L.

    1979-01-01

    A brief review of cytometry instrumentation and its potential applications in tumor biology is presented using our recent data. Age-distribution measurements of cells from spontaneous dog tumors and cultured cells after exposure to x rays, alpha particles, or adriamycin are shown. The data show that DNA fluorescence measurements have application in the study of cell kinetics after either radiation or drug treatment. Extensive and careful experimentation is needed to utilize the sophisticated developments in flow cytometry instrumentation.

  6. X-ray-induced bystander response reduce spontaneous mutations in V79 cells

    International Nuclear Information System (INIS)

    Maeda, Munetoshi; Kobayashi, Katsumi; Matsumoto, Hideki; Usami, Noriko; Tomiya, Masanori

    2013-01-01

    The potential for carcinogenic risks is increased by radiation-induced bystander responses; these responses are the biological effects in unirradiated cells that receive signals from the neighboring irradiated cells. Bystander responses have attracted attention in modern radiobiology because they are characterized by non-linear responses to low-dose radiation. We used a synchrotron X-ray microbeam irradiation system developed at the Photon Factory, High Energy Accelerator Research Organization, KEK, and showed that nitric oxide (NO)-mediated bystander cell death increased biphasically in a dose-dependent manner. Here, we irradiated five cell nuclei using 10 × 10 µm 2 5.35 keV X-ray beams and then measured the mutation frequency at the hypoxanthine-guanosine phosphoribosyl transferase (HPRT) locus in bystander cells. The mutation frequency with the null radiation dose was 2.6 × 10 -5 (background level), and the frequency decreased to 5.3 × 10 -6 with a dose of approximately 1 Gy (absorbed dose in the nucleus of irradiated cells). At high doses, the mutation frequency returned to the background level. A similar biphasic dose-response effect was observed for bystander cell death. Furthermore, we found that incubation with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), a specific scavenger of NO, suppressed not only the biphasic increase in bystander cell death but also the biphasic reduction in mutation frequency of bystander cells. These results indicate that the increase in bystander cell death involves mechanisms that suppress mutagenesis. This study has thus shown that radiation-induced bystander responses could affect processes that protect the cell against naturally occurring alterations such as mutations. (author)

  7. Spontaneous loss and alteration of antigen receptor expression in mature CD4+ T cells

    International Nuclear Information System (INIS)

    Kyoizumi, Seishi; Akiyama, Mitoshi; Hirai, Yuko; Kusunoki; Yoichiro; Tanabe, Kazumi; Umeki, Shigeko; Nakamura, Nori; Yamakido, Michio; Hamamoto, Kazuko.

    1990-04-01

    The T-cell receptor CD3 (TCR/CD3) complex plays a central role in antigen recognition and activation of mature T cells, and therefore abnormalities in the expression of the complex should induce unresponsiveness of T cells to antigen stimulus. Using flow cytometry, we detected and enumerated variant cells with loss or alteration of surface TCR/CD3 expression among human mature CD4 + T cells. The presence of variant CD4 + T cells was demonstrated by isolating and cloning them from peripheral blood, and their abnormalities can be accounted for by alterations in TCR expression such as defects of protein expression and partial protein deletion. The variant frequency in peripheral blood increased with aging in normal donors and was highly elevated in patients with ataxia telangiectasia, an autosomal recessive inherited disease with defective DNA repair and variable T-cell immunodeficiency. These findings suggest that such alterations in TCR expression are induced by somatic mutagenesis of TCR genes and can be important factors related to age-dependent and genetic disease-associated T-cell dysfunction. (author)

  8. Disruption of the p53-mediated G{sub 1}/S cell cycle checkpoint results in elevated rates of spontaneous genetic recombination in human fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Strasfeld, L.; Brainerd, E.; Meyn, M.S. [Yale Univ. School of Medicine, New Haven, CT (United States)

    1994-09-01

    A key feature of the cancer-prone inherited disease ataxia-telangiectasia (A-T) is genetic instability. We recently demonstrated that one aspect of genetic instability in A-T is a marked elevation in the spontaneous rates of intrachromosomal mitotic recombination. We have proposed a model for A-T that attributes these high recombination rates to a lack of DNA damage-sensitive cell cycle checkpoints. One prediction of this model is that disrupting p53 function in normal cells should increase their spontaneous rates of recombination by interfering with their p53-dependent G{sub 1}/S cell cycle checkpoint. To test this prediction, we transfected control and A-T fibroblast lines that each harbor a single integrated copy of lacZ-based recombination vector (pLrec) with derivatives of a eukaryotic expression vector (pRep5) that contain either a dominant-negative p53 mutant (143{sup val{yields}ala}) or a human papilloma virus E6 gene (HPV18 E6). Expression of either of these genes results in loss of p53 function and abolition of the G{sub 1}/S cell cycle checkpoint. Four independent p53{sup 143ala} transformants of the control line showed 25-80 fold elevations in spontaneous recombination rates when compared to their parent cell line. Elevations in spontaneous recombination rates were also detected following transfection with the HPV18 E6 gene. In contrast, four independent p53{sup 143ala} transformants of the A-T cell line showed no significant changes in their already high spontaneous recombination rates. We are now extending these observations to additional normal human fibroblast lines and carrying out molecular analyses of the products of these recombinational events. Our results support our hypothesis that the lack of a p53-dependent G{sub 1}/S cell cycle checkpoint contributes to the hyperrecombination seen in A-T.

  9. Role of primary T-cell immunodeficiency and hepatitis B coinfection on spontaneous clearance of hepatitis C: The BC Hepatitis Testers Cohort.

    Science.gov (United States)

    Islam, N; Krajden, M; Gilbert, M; Gustafson, P; Yu, A; Kuo, M; Chong, M; Alvarez, M; Wong, J; Tyndall, M W; Janjua, N Z

    2017-05-01

    T-cell host immune response against hepatitis C virus (HCV) has been suggested to play an important role in determining HCV infection outcome. However, data from human studies are not available. This study examined the effect of primary T-cell deficiency along with other factors on the spontaneous clearance of HCV in a large population-based cohort in British Columbia, Canada. The BC Hepatitis Testers Cohort includes all individuals tested for HCV in BC in 1990-2013 linked with data on their medical visits, hospitalizations and prescription drugs. HCV-positive individuals with at least one valid HCV PCR test on/after HCV diagnosis (n=46 783) were included in this study. To examine factors associated with the spontaneous clearance of HCV, multivariable logistic regression was fitted on the full sample, and Cox proportional hazards model on the HCV seroconverters. Spontaneous clearance was observed in 25.1% (n=11 737) of those tested for HCV. After adjusting for potential confounders, the odds of spontaneous clearance of HCV was lower in people with primary T-cell immunodeficiency (adjusted odds ratio [aOR]: 0.55, 95% CI: 0.32-0.94), and higher in females (aOR: 1.61, 95% CI: 1.54-1.68) and in those coinfected with HBV (aOR: 2.31, 95% CI: 1.93-2.77). Similar results were observed in HCV seroconverters except HBV coinfection was not significant. In conclusion, primary T-cell immunodeficiency is associated with a lower spontaneous clearance of HCV while female sex and coinfection with HBV are associated with a higher spontaneous clearance. © 2016 John Wiley & Sons Ltd.

  10. Graphene nanoplatelets spontaneously translocate into the cytosol and physically interact with cellular organelles in the fish cell line PLHC-1

    Energy Technology Data Exchange (ETDEWEB)

    Lammel, Tobias; Navas, José M., E-mail: jmnavas@inia.es

    2014-05-01

    Highlights: • We assessed the cytotoxicity and uptake of graphene nanomaterials in PLHC-1 cells. • GO and CXYG nanoplatelets caused physical injury of the plasma membrane. • GO and CXYG accumulated in the cytosol and interacted with cellular organelles. • PLHC-1 cells exposed to GO/CXYG demonstrated high ROS levels but low cytotoxicity. • ROS formation was related with GO/CXYG-induced structural damage of mitochondria. - Abstract: Graphene and graphene derivatives constitute a novel class of carbon-based nanomaterials being increasingly produced and used in technical and consumer applications. Release of graphene nanoplatelets during the life cycle of these applications may result in human and environmental exposure calling for assessment of their potential to cause harm to humans and wildlife. This study aimed to assess the toxicity of graphene oxide (GO) and carboxyl graphene (CXYG) nanoplatelets to non-mammalian species using the fish cell line PLHC-1 as in vitro model. The cytotoxicity of GO and CXYG was assessed using different assays measuring alterations in plasma membrane integrity, metabolic activity, and lysosomal and mitochondrial function. The induction of oxidative stress was assessed by measuring intracellular reactive oxygen species (ROS) levels. Interaction with the plasma membrane and internalization of nanoplatelets were investigated by electron microscopy. Graphene nanoplatelets spontaneously penetrated through the plasma membrane and accumulated in the cytosol, where they further interacted with mitochondrial and nuclear membranes. PLHC-1 cells demonstrated significantly reduced mitochondrial membrane potential (MMP) and increased ROS levels at 16 μg/ml GO and CXYG (72 h), but barely any decrease in cell viability. The observation of intracellular graphene accumulations not enclosed by membranes suggests that GO and CXYG internalization in fish hepatoma cells occurs through an endocytosis-independent mechanism.

  11. Technique, pharmacokinetics, toxicity, and efficacy of intratumoral etanidazole and radiotherapy for treatment of spontaneous feline oral squamous cell carcinoma

    International Nuclear Information System (INIS)

    Evans, S.M.; LaCreta, F.; Helfand, S.; VanWinkle, T.; Curran, W.J. Jr.; Brown, D.Q.; Hanks, G.

    1991-01-01

    The histologic appearance, locoregional recurrence, and rate/site of metastases of spontaneous feline oral squamous cell carcinoma are similar to head and neck cancer in humans. A feasibility study of intratumoral Etanidazole, a hypoxic cell sensitizer, and radiation therapy were instituted in this model. Eleven cats with feline squamous cell carcinoma were treated with intratumoral Etanidazole and radiation therapy. Total Etanidazole doses were 1.5-24.0 gms/m2 (0.5-6.9 gms). The tumor partial response rate was 100% (11/11); the median volume regression was 70%. All cats have died as a result of tumor recurrence or tumor-related complications. Median survival was 116 days. Ten cats have been autopsied. Non-necrotic and necrotic tumor cells were identified at the treatment site in all cats. Pharmacokinetic studies were performed in six cats. Following intravenous infusion, the plasma elimination of the Etanidazole was biexponential. The systemic availability following intratumoral administration was 61.2 +/- 21.1%. Peak plasma Etanidazole levels were observed 14 minutes following intratumoral injection, after which elimination was biexponential. Thirty minutes following intratumoral Etanidazole administration, tumor Etanidazole levels were 62.8% of plasma levels. Feline squamous cell carcinoma appears to be a useful model of human head and neck cancer. Cats tolerate substantial doses of intratumoral and intravenous Etanidazole. Etanidazole and radiation therapy cause rapid regression, but not cure, of feline squamous cell carcinoma. There is a similarity between the intravenous kinetics of Etanidazole in humans and cats. Further studies in this model are planned

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

    Science.gov (United States)

    Takigawa, Hidehiko; Kitadai, Yasuhiko; Shinagawa, Kei; Yuge, Ryo; Higashi, Yukihito; Tanaka, Shinji; Yasui, Wataru; Chayama, Kazuaki

    2017-05-01

    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. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  13. The role of the sympathetic nervous system in radiation-induced apoptosis in jejunal crypt cells of spontaneously hypertensive rats

    International Nuclear Information System (INIS)

    Matsuu, Mutsumi; Shichijo; Kazuko; Nakamura, Yasuko; Ikeda, Yuji; Naito, Shinji; Ito, Masahiro; Okaichi, Kumio; Sekine, Ichiro

    2000-01-01

    To evaluate the effect of the sympathetic nervous system on radiation-induced apoptosis in jejunal crypt cells, apoptosis levels were compared in spontaneously hypertensive rats (SHR), animals which are a genetic hyperfunction model of the sympathetic nervous system, and normotensive Wistar-Kyoto rats (WKY). SHR and WKY were exposed to whole body X-ray irradiation at doses from 0.5 to 2 Gy. The apoptotic index in jejunal crypt cells was significantly greater in SHR than in WKY at each time point after irradiation and at each dose. WKY and SHR were treated with reserpine to induce sympathetic dysfunction, and were subsequently exposed to irradiation. Reserpine administration to SHR or WKY resulted in a significant suppression of apoptosis. p53 accumulation was detected in the jejunum in both WKY and SHR after irradiation by Western blotting analysis. There were no significant differences in the levels of p53 accumulation in irradiated intestine between WKY and SHR. These findings suggested that hyperfunction of the sympathetic nervous system is involved in the mechanism of high susceptibility to radiation-induced apoptosis of the jejunal crypt cells. (author)

  14. Human neural stem cell-derived cultures in three-dimensional substrates form spontaneously functional neuronal networks.

    Science.gov (United States)

    Smith, Imogen; Silveirinha, Vasco; Stein, Jason L; de la Torre-Ubieta, Luis; Farrimond, Jonathan A; Williamson, Elizabeth M; Whalley, Benjamin J

    2017-04-01

    Differentiated human neural stem cells were cultured in an inert three-dimensional (3D) scaffold and, unlike two-dimensional (2D) but otherwise comparable monolayer cultures, formed spontaneously active, functional neuronal networks that responded reproducibly and predictably to conventional pharmacological treatments to reveal functional, glutamatergic synapses. Immunocytochemical and electron microscopy analysis revealed a neuronal and glial population, where markers of neuronal maturity were observed in the former. Oligonucleotide microarray analysis revealed substantial differences in gene expression conferred by culturing in a 3D vs a 2D environment. Notable and numerous differences were seen in genes coding for neuronal function, the extracellular matrix and cytoskeleton. In addition to producing functional networks, differentiated human neural stem cells grown in inert scaffolds offer several significant advantages over conventional 2D monolayers. These advantages include cost savings and improved physiological relevance, which make them better suited for use in the pharmacological and toxicological assays required for development of stem cell-based treatments and the reduction of animal use in medical research. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Bioenergetics in chicken embryo fibroblast cells: evidence of lower proton leak in spontaneously immortalized chicken embryo fibroblasts compared to young and senescent primary chicken embryo fibroblast cells.

    Science.gov (United States)

    Lassiter, Kentu; Dridi, Sami; Piekarski, Alissa; Greene, Elizabeth; Hargis, Billy; Kong, Byung-Whi; Bottje, Walter

    2014-09-01

    A spontaneously immortalized chicken embryo fibroblast (CEF) cell line (DF-1) is known to exhibit faster growth rate and greater sensitivity to oxidative stress compared to the primary parent CEF (pCEF1°) cells. Thus, major objectives of this study were to assess cell bioenergetics in pCEF1° and DF-1 cells under control conditions and in response to 4-hydroxy 2-nonenal (4-HNE) induced oxidative challenge. Cell bioenergetics were assessed by flux analysis of oxygen consumption rate (OCR). Under control conditions, DF-1 cells had higher OCR associated with ATP synthase activity and mitochondrial oxygen reserve capacity as well as lower OCR due to proton leak and non-mitochondrial cytochrome c oxidase activity. In response to 4-HNE (0 to 30 μM), DF-1 cells were more sensitive to oxidant challenge than both young (passage 8) and senescent (passage 19) pCEF1° cells. Both passages 8 and 19 pCEF1° cells exhibited higher proton leak in response to 4-HNE, but this was not observed in DF-1 cells. Inducible proton leak occurs by 4-HNE stimulated activation of uncoupling protein (UCP) and adenine nucleotide translocase (ANT). From mRNA expression data indicated that ANT and avian UCP were down-regulated and up-regulated, respectively, in DF-1 compared to pCEF1° cells. Thus, we hypothesize that DF-1 cells are unable to increase proton leak due to lower expression of ANT, but not avian UCP, and this inability to increase proton leak contributes to greater susceptibility to oxidative stress of DF-1 cells compared to pCEF1° cells. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Spontaneous and induced chromosomal aberrations in bone marrow cells of mice of different strain and age

    Energy Technology Data Exchange (ETDEWEB)

    Lil' p, J.G.; Korogodina, Yu.V. (Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Meditsinskoj Genetiki)

    1981-01-01

    The sensitivity of bone marrow cell chromosomes both to an alkylating agent thiophosphamide and ..gamma..-irradiation in 101/H, A/He, CBA, BALB/c and C57BL/6 aging mice has been studied. Changes in the sensitivity of bone marrow cell chromosomes with age are shown to depend both on mutagenic effect type and animal's genotype. The age dependent yield of chromosomal aberrations did not change in mice of all studied strains after ..gamma..-irradiation under conditions of our experiments. After the thiophosphamide effect, an increased sensitivity of bone marrow cell chromosomes was observed in the old 101/H, A/He and CBA mice as compared to the young ones. The level of induced chromosomal aberrations in C57BL/6 mice did not vary with age. Cells exhibiting multiple damages to chromosomes occurred in the bone marrow following the thiophosphamide effect. An increased sensitivity of old animals of certain strains resulted mainly from a sharp numerical growth of such cells. No increase in the number of cells in intact animals of all strains related to age dependent chromosomal structural damages was observed, whereas the accumulation of aneuploid cells probably depended on the genotype.

  17. Reduced IL-37 Production Increases Spontaneous Chemokine Expressions in Colon Epithelial Cells

    NARCIS (Netherlands)

    Günaltay, Sezin; Ghiboub, Mohammed; Hultgren, Olof; Hörnquist, Elisabeth Hultgren

    2017-01-01

    Microscopic colitis, comprising collagenous colitis and lymphocytic colitis, is a common cause of chronic diarrhea. Previously, we showed enhanced chemokine productions in microscopic colitis patients, indicating dysregulated immune cell chemotaxis in the immunopathogenesis. We also showed decreased

  18. Analysing the Influence of the Spontaneous Aneuploidy Frequency on the Cell Population System Cultivation

    Directory of Open Access Journals (Sweden)

    G. A. Nefedov

    2015-01-01

    Full Text Available The paper provides a qualitative analysis of M.S. Vinogradova's nonlinear model for dynamics of the cell population system. This system describes the stem cells cultivation in vitro under resource constraints. The system consists of two populations, namely: population of normal cells and population of abnormal cells. Resource constraints are considered as linear dependences of mitosis parameters on the normalized densities of each population.One of the key parameters that effects on the realization of the system evolution scenarios is a parameter that determines a share of the normal cells, which pass, when dividing, into population of the abnormal cells. The paper analyses both the existence conditions of the rest points and the changes of the evolution scenarios of population system with changing abovementioned parameter and other system parameters held fixed. It is shown that there is a saddle-node bifurcation in the system; the bifurcation value of the parameter is found. The paper shows the interval of parameter values in which the favorable scenarios of population system evolution are implemented. It also presents results of mathematical modeling.

  19. TRANSIT

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. TRANSIT. SYSTEM: DETERMINE 2D-POSITION GLOBALLY BUT INTERMITTENT (POST-FACTO). IMPROVED ACCURACY. PRINCIPLE: POLAR SATELLITES WITH INNOVATIONS OF: GRAVITY-GRADIENT ATTITUDE CONTROL; DRAG COMPENSATION. WORKS ...

  20. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2011

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.; Gikakis, C.

    2011-11-01

    This status report, fifth in a series of annual status reports from the U.S. Department of Energy's National Renewable Energy Laboratory (NREL), discusses the achievements and challenges of fuel cell propulsion for transit and summarizes the introduction of fuel cell transit buses in the United States. Progress this year includes an increase in the number of fuel cell electric buses (FCEBs), from 15 to 25, operating at eight transit agencies, as well as increased diversity of the fuel cell design options for transit buses. The report also provides an analysis of the combined results from fuel cell transit bus demonstrations evaluated by NREL with a focus on the most recent data through July 2011 including fuel cell power system reliability and durability; fuel economy; roadcall; and hydrogen fueling results. These evaluations cover 22 of the 25 FCEBs currently operating.

  1. "Plastic" solar cells: self-assembly of bulk heterojunction nanomaterials by spontaneous phase separation.

    Science.gov (United States)

    Peet, Jeffrey; Heeger, Alan J; Bazan, Guillermo C

    2009-11-17

    As the global demand for low-cost renewable energy sources intensifies, interest in new routes for converting solar energy to electricity is rapidly increasing. Although photovoltaic cells have been commercially available for more than 50 years, only 0.1% of the total electricity generated in the United States comes directly from sunlight. The earliest commercial solar technology remains the basis for the most prevalent devices in current use, namely, highly-ordered crystalline, inorganic solar cells, commonly referred to as silicon cells. Another class of solar cells that has recently inspired significant academic and industrial excitement is the bulk heterojunction (BHJ) "plastic" solar cell. Research by a rapidly growing community of scientists across the globe is generating a steady stream of new insights into the fundamental physics, the materials design and synthesis, the film processing and morphology, and the device science and architecture of BHJ technology. Future progress in the fabrication of high-performance BHJ cells will depend on our ability to combine aspects of synthetic and physical chemistry, condensed matter physics, and materials science. In this Account, we use a combination of characterization tools to tie together recent advances in BHJ morphology characterization, device photophysics, and thin-film solution processing, illustrating how to identify the limiting factors in solar cell performance. We also highlight how new processing methods, which control both the BHJ phase separation and the internal order of the components, can be implemented to increase the power conversion efficiency (PCE). The failure of many innovative materials to achieve high performance in BHJ solar cell devices has been blamed on "poor morphology" without significant characterization of either the structure of the phase-separated morphology or the nature of the charge carrier recombination. We demonstrate how properly controlling the "nanomorphology", which is

  2. Features of the alpha-cell population organization in pancreas of spontaneously hypertensive rats (SHR

    Directory of Open Access Journals (Sweden)

    T. V. Abramova

    2017-08-01

    Full Text Available Alpha cells of pancreatic islets constitute the second largest population of pancreatic endocrinocytes, and the glucagon synthesized in them plays an important role in the regulation of glucose homeostasis. At the same time, glucagon-suppressive therapy is defined as the strategically main source of success of therapy for patients with type 2 diabetes mellitus. In clinical practice, diabetes is often associated with hypertension in the metabolic syndrome, which causes interest in the pathophysiology of α-endocrinocytes. The aim of the study was to investigate the distribution parameters of α-cells in the pancreatic islets of SHR and to characterize the morphological and functional state of glucagon-synthesizing endocrinocytes Materials and methods. In the histological sections of the pancreas, glucagon was detected by the immunofluorescence method; the area of pancreatic islets, as well as the number of α-cells in them, the concentration of immunoreactive glucagon in these cells, the specific indices of the distribution of islets, α-cells and glucagon per unit area of the gland. The results were processed with a package of statistical programs, to assess the reliability of the differences in the groups, the Student’s t-test and the Wilcoxon W-test were used. Results. In normoglycemic SHR, the number of islets containing glucagon-synthesizing α-cells was 10% more (p <0.05 than in normotensive Wistar rats. In the pancreatic tissue, single α-endocrine cells were found in rats of both lines, not forming separate islets. In giant islets of SHR there were 72% more α-endocrine cells than in Wistar rats, and in large islets this difference was twofold. Accordingly, α-cells of these islets contributed significantly to higher glucagon levels in the pancreas of hypertensive rats: in giant islets, the amount of the hormone was 80%, and in large islets – 3.6 times higher than in normotensive rats. In this paper we discuss the mechanisms that lead

  3. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2017

    Science.gov (United States)

    2017-11-01

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of ...

  4. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2014

    Science.gov (United States)

    2014-12-03

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. Various stakeholders, including d...

  5. 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

  6. Spontaneous regression of primary diffuse large B-cell lymphoma, leg type.

    Science.gov (United States)

    Alcántara-González, J; González-García, C; Fernández-Guarino, M; Jaén-Olasolo, P

    2014-01-01

    Primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL LT) accounts for approximately 20% of all primary cutaneous B-cell lymphomas and tends to present as infiltrated nodules, tumors, and plaques on the legs in the elderly. Unlike other primary cutaneous large B-cell lymphomas, it has a poor prognosis and tends to require treatment with systemic chemotherapy. We present the case of an 82-year-old patient with a 1-year history of nodules and plaques on her right leg. Biopsy led to a diagnosis of PCLBCL LT and the lesions resolved without treatment within 1 month of the first visit. This is an atypical course of PCLBCL LT and we believe that it is the first such case to be reported in the literature. Copyright © 2012 Elsevier España, S.L. and AEDV. All rights reserved.

  7. Differentially expressed genes during spontaneous lytic switch of Marek's disease virus in lymphoblastoid cell lines determined by global gene expression profiling.

    Science.gov (United States)

    Mwangi, William N; Vasoya, Deepali; Kgosana, Lydia B; Watson, Mick; Nair, Venugopal

    2017-04-01

    Marek's disease virus (MDV), an alphaherpesvirus of poultry, causes Marek's disease and is characterized by visceral CD4+TCRαβ+ T-cell lymphomas in susceptible hosts. Immortal cell lines harbouring the viral genome have been generated from ex vivo cultures of MD tumours. As readily available sources of large numbers of cells, MDV-transformed lymphoblastoid cell lines (LCLs) are extremely valuable for studies of virus-host interaction. While the viral genome in most cells is held in a latent state, minor populations of cells display spontaneous reactivation identifiable by the expression of lytic viral genes. Spontaneous reactivation in these cells presents an opportunity to investigate the biological processes involved in the virus reactivation. For detailed characterization of the molecular events associated with reactivation, we used two lymphoblastoid cell lines derived from lymphomas induced by pRB1B-UL47eGFP, a recombinant MDV engineered to express enhanced green fluorescent protein (EGFP) fused with the UL47. We used fluorescence-activated cell sorting to purify the low-frequency EGFP-positive cells with a spontaneously activating viral genome from the majority EGFP-negative cells and analysed their gene expression profiles by RNA-seq using Illumina HiSeq2500. Ingenuity pathway analysis on more than 2000 differentially expressed genes between the lytically infected (EGFP-positive) and latently infected (EGFP-negative) cell populations identified the biological pathways involved in the reactivation. Virus-reactivating cells exhibited differential expression of a significant number of viral genes, with hierarchical differences in expression levels. Downregulation of a number of host genes including those directly involved in T-cell activation, such as CD3, CD28, ICOS and phospholipase C, was also noticed in the LCL undergoing lytic switch.

  8. Peripheral blood cells from children with RASopathies show enhanced spontaneous colonies growth in vitro and hyperactive RAS signaling

    International Nuclear Information System (INIS)

    Gaipa, G; Bugarin, C; Cianci, P; Sarno, J; Bonaccorso, P; Biondi, A; Selicorni, A

    2015-01-01

    Germline mutations in genes coding for molecules involved in the RAS/RAF/MEK/ERK pathway are the hallmarks of a newly classified family of autosomal dominant syndromes termed RASopathies. Myeloproliferative disorders (MPDs), in particular, juvenile myelomonocytic leukemia, can lead to potentially severe complications in children with Noonan syndrome (NS). We studied 27 children with NS or other RASopathies and 35 age-matched children as control subjects. Peripheral blood (PB) cells from these patients were studied for in vitro colony-forming units (CFUs) activity, as well as for intracellular phosphosignaling. Higher spontaneous growth of both burst-forming units-erythroid (BFU-E) and CFU-granulocyte/macrophage (CFU-GM) colonies from RAS-mutated patients were observed as compared with control subjects. We also observed a significantly higher amount of GM-colony-stimulating factor-induced p-ERK in children with RASopathies. Our findings demonstrate for the first time that PB cells isolated from children suffering from NS or other RASopathies without MPD display enhanced BFU-E and CFU-GM colony formation in vitro. The biological significance of these findings clearly awaits further studies. Collectively, our data provide a basis for further investigating of only partially characterized hematological alterations present in children suffering from RASopathies, and may provide new markers for progression toward malignant MPD in these patients

  9. Modeling self-organized spatio-temporal patterns of PIP3 and PTEN during spontaneous cell polarization

    International Nuclear Information System (INIS)

    Knoch, Fabian; Tarantola, Marco; Bodenschatz, Eberhard; Rappel, Wouter-Jan

    2014-01-01

    During spontaneous cell polarization of Dictyostelium discoideum cells, phosphatidylinositol (3,4,5)-triphoshpate (PIP 3 ) and PTEN (phosphatase tensin homolog) have been identified as key signaling molecules which govern the process of polarization in a self-organized manner. Recent experiments have quantified the spatio-temporal dynamics of these signaling components. Surprisingly, it was found that membrane-bound PTEN can be either in a high or low state, that PIP 3 waves were initiated in areas lacking PTEN through an excitable mechanism, and that PIP 3 was degraded even though the PTEN concentration remained low. Here we develop a reaction-diffusion model that aims to explain these experimental findings. Our model contains bistable dynamics for PTEN, excitable dynamics for PIP 3 , and postulates the existence of two species of PTEN with different dephosphorylation rates. We show that our model is able to produce results that are in good qualitative agreement with the experiments, suggesting that our reaction-diffusion model underlies the self-organized spatio-temporal patterns observed in experiments. (paper)

  10. Modeling self-organized spatio-temporal patterns of PIP3 and PTEN during spontaneous cell polarization

    Science.gov (United States)

    Knoch, Fabian; Tarantola, Marco; Bodenschatz, Eberhard; Rappel, Wouter-Jan

    2014-08-01

    During spontaneous cell polarization of Dictyostelium discoideum cells, phosphatidylinositol (3,4,5)-triphoshpate (PIP3) and PTEN (phosphatase tensin homolog) have been identified as key signaling molecules which govern the process of polarization in a self-organized manner. Recent experiments have quantified the spatio-temporal dynamics of these signaling components. Surprisingly, it was found that membrane-bound PTEN can be either in a high or low state, that PIP3 waves were initiated in areas lacking PTEN through an excitable mechanism, and that PIP3 was degraded even though the PTEN concentration remained low. Here we develop a reaction-diffusion model that aims to explain these experimental findings. Our model contains bistable dynamics for PTEN, excitable dynamics for PIP3, and postulates the existence of two species of PTEN with different dephosphorylation rates. We show that our model is able to produce results that are in good qualitative agreement with the experiments, suggesting that our reaction-diffusion model underlies the self-organized spatio-temporal patterns observed in experiments.

  11. Cyclooxygenase-2 inhibitor induces apoptosis in breast cancer cells in an in vivo model of spontaneous metastatic breast cancer.

    Science.gov (United States)

    Basu, Gargi D; Pathangey, Latha B; Tinder, Teresa L; Lagioia, Michelle; Gendler, Sandra J; Mukherjee, Pinku

    2004-11-01

    Cyclooxygenase-2 (COX-2) inhibitors are rapidly emerging as a new generation of therapeutic drug in combination with chemotherapy or radiation therapy for the treatment of cancer. The mechanisms underlying its antitumor effects are not fully understood and more thorough preclinical trials are needed to determine if COX-2 inhibition represents a useful approach for prevention and/or treatment of breast cancer. The purpose of this study was to evaluate the growth inhibitory mechanism of a highly selective COX-2 inhibitor, celecoxib, in an in vivo oncogenic mouse model of spontaneous breast cancer that resembles human disease. The oncogenic mice carry the polyoma middle T antigen driven by the mouse mammary tumor virus promoter and develop primary adenocarcinomas of the breast. Results show that oral administration of celecoxib caused significant reduction in mammary tumor burden associated with increased tumor cell apoptosis and decreased proliferation in vivo. In vivo apoptosis correlated with significant decrease in activation of protein kinase B/Akt, a cell survival signaling kinase, with increased expression of the proapoptotic protein Bax and decreased expression of the antiapoptotic protein Bcl-2. In addition, celecoxib treatment reduced levels of proangiogenic factor (vascular endothelial growth factor), suggesting a role of celecoxib in suppression of angiogenesis in this model. Results from these preclinical studies will form the basis for assessing the feasibility of celecoxib therapy alone or in combination with conventional therapies for treatment and/or prevention of breast cancer.

  12. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2013

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gikakis, Christina [Federal Transit Administration, Washington, DC (United States)

    2013-12-01

    This report is the seventh in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results from August 2012 through July 2013 for five FCEB demonstrations at four transit agencies.

  13. EDITORIAL SPONTANEOUS BACTERIAL PERITONITIS ...

    African Journals Online (AJOL)

    hi-tech

    Spontaneous bacterial peritonitis (SBP) frequent]y occurs in patients with liver cirrhosis and ascites. It is defined as an infection of previously sterile ascitic fluid without any demonstrable intrabdominal source of infection. It is now internationally agreed that a polymorphonuclear (PMN) cell count in the ascitic fluid of over 250 ...

  14. Spontaneous deregulation

    NARCIS (Netherlands)

    Edelman, Benjamin; Geradin, Damien

    Platform businesses such as Airbnb and Uber have risen to success partly by sidestepping laws and regulations that encumber their traditional competitors. Such rule flouting is what the authors call “spontaneous private deregulation,” and it’s happening in a growing number of industries. The authors

  15. Staging of transitional cell carcinoma: Has anything changed?

    Directory of Open Access Journals (Sweden)

    J N Kulkarni

    2008-01-01

    Full Text Available Objective: This article is a systematic review of various changes in the evolution of the contemporary clinico-pathological staging of transitional cell carcinoma (TCC. Materials and Methods: A thorough search of the literature was done by Medline and other internet references. Results: Accurate staging of TCC is necessary for designing optimal therapy in clinical practice. Further, the current emphasis on bladder conservation and improved long-term disease free survival (DFS necessitates minimal errors in staging and it′s predictability towards recurrence and progression. Traditionally, the staging of TCC revolves around clinical and pathological findings. The staging has evolved through the understanding of various clinico- pathological factors like tumor appearance, number, size, grade, depth of invasion, muscle substratification, lymphovascular invasion and has reached the standard TNM classification. Cystoscopy and transurethral resection still remain the mainstay of staging and noninvasive imaging techniques have further enhanced the accuracy. Conclusion: The TNM classification for bladder cancer is currently the gold standard for TCC.

  16. Types of HLA in the bladder transitional cell carcinoma (TCC).

    Science.gov (United States)

    Yılmaz, Erkan; Uğur Özalp, Ali; Cekmen, Arman; Eren, Bülent; Onal, Bülent; Akkuş, Emre; Erdoğan, Ergun

    2013-02-01

    HLA plays a complementary role in the interaction between tumor and body immunology. The aim of this study was to determine the existence of the association between the HLA system and transitional cell carcinoma (TCC). Using standard micro-lymphocytotoxic method of Terasaki, HLA-A, B, DR and DQ antigen types of 30 patients with TCC of the bladder were compared with the control group (30 healthy people). In the TCC patient group, HLA -DQ6(1) and HLA -DQ7(3) antigens were detected with a significantly higher frequency than in the control group (p=0.018 and p=0.038, respectively), whereas HLA-A10, B4, DR53 and DQ1 antigens were detected with significantly higher frequency in the control group (p less 0.05 in all). It suggests that patients who had the antigens detected were at higher risk of TCC, and the ones who had the antigens displaying protective features as were detected in the control group, were at lesser risk.

  17. Transition zone cells reach G2 phase before initiating elongation in maize root apex

    Directory of Open Access Journals (Sweden)

    M. Victoria Alarcón

    2017-06-01

    Full Text Available Root elongation requires cell divisions in the meristematic zone and cell elongation in the elongation zone. The boundary between dividing and elongating cells is called the transition zone. In the meristem zone, initial cells are continuously dividing, but on the basal side of the meristem cells exit the meristem through the transition zone and enter in the elongation zone, where they stop division and rapidly elongate. Throughout this journey cells are accompanied by changes in cell cycle progression. Flow cytometry analysis showed that meristematic cells are in cycle, but exit when they enter the elongation zone. In addition, the percentage of cells in G2 phase (4C strongly increased from the meristem to the elongation zone. However, we did not observe remarkable changes in the percentage of cells in cell cycle phases along the entire elongation zone. These results suggest that meristematic cells in maize root apex stop the cell cycle in G2 phase after leaving the meristem.

  18. Spontaneous Remission of an Untreated, MYC and BCL2 Coexpressing, High-Grade B-Cell Lymphoma: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    D. Alan Potts

    2017-01-01

    Full Text Available Non-Hodgkin lymphomas (NHL are a heterogeneous group of hematologic malignancies typically treated with multiagent chemotherapy. Rarely, spontaneous remissions can be observed, particularly in more indolent subtypes. The prognosis of aggressive NHL can be predicted using clinical and histopathologic factors. In aggressive B-cell NHL, the importance of MYC and BCL2 proto-oncogene coexpression (as assessed by immunohistochemistry and high-grade histologic features are particularly noteworthy. We report a unique case of spontaneous remission in a patient with an aggressive B-cell NHL which harbored high-risk histopathologic features, including MYC protein expression at 70–80%, BCL2 protein expression, and morphologic features suggestive of high-grade B-cell lymphoma, NOS (formerly B-cell lymphoma unclassifiable with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma [BCLU]. After undergoing a biopsy to confirm this diagnosis, he opted to forego curative-intent chemotherapy. The single, yet relatively large area of involvement noted on 18F-fluorodeoxyglucose positron emission tomography-computed tomography steadily resolved on subsequent follow-up studies. He remained without evidence of recurrence one year later, having never received treatment. This case emphasizes the potential for spontaneous remission in NHL and demonstrates that this phenomenon can be observed despite contemporary high-risk histopathologic features.

  19. The activity of spontaneous action potentials in developing hair cells is regulated by Ca(2+-dependence of a transient K+ current.

    Directory of Open Access Journals (Sweden)

    Snezana Levic

    Full Text Available Spontaneous action potentials have been described in developing sensory systems. These rhythmic activities may have instructional roles for the functional development of synaptic connections. The importance of spontaneous action potentials in the developing auditory system is underpinned by the stark correlation between the time of auditory system functional maturity, and the cessation of spontaneous action potentials. A prominent K(+ current that regulates patterning of action potentials is I(A. This current undergoes marked changes in expression during chicken hair cell development. Although the properties of I(A are not normally classified as Ca(2+-dependent, we demonstrate that throughout the development of chicken hair cells, I(A is greatly reduced by acute alterations of intracellular Ca(2+. As determinants of spike timing and firing frequency, intracellular Ca(2+ buffers shift the activation and inactivation properties of the current to more positive potentials. Our findings provide evidence to demonstrate that the kinetics and functional expression of I(A are tightly regulated by intracellular Ca(2+. Such feedback mechanism between the functional expression of I(A and intracellular Ca(2+ may shape the activity of spontaneous action potentials, thus potentially sculpting synaptic connections in an activity-dependent manner in the developing cochlea.

  20. Representation of spontaneous movement by dopaminergic neurons is cell-type selective and disrupted in parkinsonism

    DEFF Research Database (Denmark)

    Dodson, Paul D.; Dreyer, Jakob K.; Jennings, Katie Ann

    2016-01-01

    receptor expressed by striatal neurons. Importantly, in aged mice harboring a genetic burden relevant for human Parkinson's disease, the precise movement-related firing of SNc dopaminergic neurons and the resultant striatal dopamine signaling were lost. These data show that distinct dopaminergic cell types......Midbrain dopaminergic neurons are essential for appropriate voluntary movement, as epitomized by the cardinal motor impairments arising in Parkinson's disease. Understanding the basis of such motor control requires understanding how the firing of different types of dopaminergic neuron relates...... of these dopaminergic neurons can manifest as rapid and robust fluctuations in striatal dopamine concentration and receptor activity. The exact nature of the movement-related signaling in the striatum depended on the type of dopaminergic neuron providing inputs, the striatal region innervated, and the type of dopamine...

  1. Characterization of spontaneous collagen fibrillogenesis in a cell-free and tension-free environment.

    Science.gov (United States)

    Piérard, G E; Hermanns-Lê, T; Delvenne, P; Piérard-Franchimont, C

    2013-06-01

    The collagen fibril packing that forms threads and bundles is poorly defined, despite the fact that it is important for distinct aspects of the adventitial and reticular dermis. The present study explored an in vitro fibrillogenesis model using the property of heat polymerization. The process was performed on glass slides with mixtures of collagen I and III, and the material was viewed by scanning electron microscopy. In all instances, collagen I and III formed fibrils with regular sizes. The formation of threads was influenced by the relative proportions of collagen I and III; increasing the relative proportion of collagen I resulted in the formation of threads showing increasing variations in thickness. These findings are in line with the differential presentation and compositions of the different parts of the dermis. The possible interventions of stromal cells and of other macromoleules of the extracellular matrix were not considered in this study. © The Author(s) CED © 2013 British Association of Dermatologists.

  2. Role of mitochondria in modulation of spontaneous Ca2+ waves in freshly dispersed interstitial cells of Cajal from the rabbit urethra.

    Science.gov (United States)

    Sergeant, Gerard P; Bradley, Eamonn; Thornbury, Keith D; McHale, Noel G; Hollywood, Mark A

    2008-10-01

    Interstitial cells of Cajal (ICC) isolated from the rabbit urethra exhibit pacemaker activity that results from spontaneous Ca(2+) waves. The purpose of this study was to investigate if this activity was influenced by Ca(2+) uptake into mitochondria. Spontaneous Ca(2+) waves were recorded using a Nipkow spinning disk confocal microscope and spontaneous transient inward currents (STICs) were recorded using the whole-cell patch clamp technique. Disruption of the mitochondrial membrane potential with the electron transport chain inhibitors rotenone (10 microm) and antimycin A (5 microm) abolished Ca(2+) waves and increased basal Ca(2+) levels. Similar results were achieved when mitochondria membrane potential was collapsed using the protonophores FCCP (0.2 microm) and CCCP (1 microm). Spontaneous Ca(2+) waves were not inhibited by the ATP synthase inhibitor oligomycin (1 microm), suggesting that these effects were not attributable to an effect on ATP levels. STICs recorded under voltage clamp at -60 mV were also inhibited by CCCP and antimycin A. Dialysis of cells with the mitochondrial uniporter inhibitor RU360 (10 microm) also inhibited STICS. Stimulation of Ca(2+) uptake into mitochondria using the plant flavonoid kaempferol (10 microm) induced a series of propagating Ca(2+) waves. The kaempferol-induced activity was inhibited by application of caffeine (10 mm) or removal of extracellular Ca(2+), but was not significantly affected by the IP(3) receptor blocker 2-APB (100 microm). These data suggest that spontaneous Ca(2+) waves in urethral ICC are regulated by buffering of cytoplasmic Ca(2+) by mitochondria.

  3. Role of mitochondria in modulation of spontaneous Ca2+ waves in freshly dispersed interstitial cells of Cajal from the rabbit urethra

    Science.gov (United States)

    Sergeant, Gerard P; Bradley, Eamonn; Thornbury, Keith D; McHale, Noel G; Hollywood, Mark A

    2008-01-01

    Interstitial cells of Cajal (ICC) isolated from the rabbit urethra exhibit pacemaker activity that results from spontaneous Ca2+ waves. The purpose of this study was to investigate if this activity was influenced by Ca2+ uptake into mitochondria. Spontaneous Ca2+ waves were recorded using a Nipkow spinning disk confocal microscope and spontaneous transient inward currents (STICs) were recorded using the whole-cell patch clamp technique. Disruption of the mitochondrial membrane potential with the electron transport chain inhibitors rotenone (10 μm) and antimycin A (5 μm) abolished Ca2+ waves and increased basal Ca2+ levels. Similar results were achieved when mitochondria membrane potential was collapsed using the protonophores FCCP (0.2 μm) and CCCP (1 μm). Spontaneous Ca2+ waves were not inhibited by the ATP synthase inhibitor oligomycin (1 μm), suggesting that these effects were not attributable to an effect on ATP levels. STICs recorded under voltage clamp at −60 mV were also inhibited by CCCP and antimycin A. Dialysis of cells with the mitochondrial uniporter inhibitor RU360 (10 μm) also inhibited STICS. Stimulation of Ca2+ uptake into mitochondria using the plant flavonoid kaempferol (10 μm) induced a series of propagating Ca2+ waves. The kaempferol-induced activity was inhibited by application of caffeine (10 mm) or removal of extracellular Ca2+, but was not significantly affected by the IP3 receptor blocker 2-APB (100 μm). These data suggest that spontaneous Ca2+ waves in urethral ICC are regulated by buffering of cytoplasmic Ca2+ by mitochondria. PMID:18703577

  4. Depletion of intrinsic expression of Interleukin-8 in prostate cancer cells causes cell cycle arrest, spontaneous apoptosis and increases the efficacy of chemotherapeutic drugs

    Directory of Open Access Journals (Sweden)

    Lokeshwar Bal L

    2009-07-01

    Full Text Available Abstract Background The progression of all cancers is characterized by increased-cell proliferation and decreased-apoptosis. The androgen-independent prostate cancer (AIPC is the terminal stage of the disease. Many chemokines and cytokines are suspects to cause this increased tumor cell survival that ultimately leads to resistance to therapy and demise of the host. The AIPC cells, but not androgen-responsive cells, constitutively express abundant amount of the pro-inflammatory chemokine, Interleukin-8 (IL-8. The mechanism of IL-8 mediated survival and therapeutic resistance in AIPC cells is unclear at present. The purpose of this report is to show the pervasive role of IL-8 in malignant progression of androgen-independent prostate cancer (AIPC and to provide a potential new therapeutic avenue, using RNA interference. Results The functional consequence of IL-8 depletion in AIPC cells was investigated by RNA interference in two IL-8 secreting AIPC cell lines, PC-3 and DU145. The non-IL-8 secreting LNCaP and LAPC-4 cells served as controls. Cells were transfected with RISC-free siRNA (control or validated-pool of IL-8 siRNA. Transfection with 50 nM IL-8 siRNA caused >95% depletion of IL-8 mRNA and >92% decrease in IL-8 protein. This reduction in IL-8 led to cell cycle arrest at G1/S boundary and decreases in cell cycle-regulated proteins: Cyclin D1 and Cyclin B1 (both decreased >50% and inhibition of ERK1/2 activity by >50%. Further, the spontaneous apoptosis was increased by >43% in IL-8 depleted cells, evidenced by increases in caspase-9 activation and cleaved-PARP. IL-8 depletion caused significant decreases in anti-apoptotic proteins, BCL-2, BCL-xL due to decrease in both mRNA and post-translational stability, and increased levels of pro-apoptotic BAX and BAD proteins. More significantly, depletion of intracellular IL-8 increased the cytotoxic activity of multiple chemotherapeutic drugs. Specifically, the cytotoxicity of Docetaxel

  5. Dysregulation of mitotic machinery genes precedes genome instability during spontaneous pre-malignant transformation of mouse ovarian surface epithelial cells

    Directory of Open Access Journals (Sweden)

    Ulises Urzúa

    2016-10-01

    Full Text Available Abstract Background Based in epidemiological evidence, repetitive ovulation has been proposed to play a role in the origin of ovarian cancer by inducing an aberrant wound rupture-repair process of the ovarian surface epithelium (OSE. Accordingly, long term cultures of isolated OSE cells undergo in vitro spontaneous transformation thus developing tumorigenic capacity upon extensive subcultivation. In this work, C57BL/6 mouse OSE (MOSE cells were cultured up to passage 28 and their RNA and DNA copy number profiles obtained at passages 2, 5, 7, 10, 14, 18, 23, 25 and 28 by means of DNA microarrays. Gene ontology, pathway and network analyses were focused in passages earlier than 20, which is a hallmark of malignancy in this model. Results At passage 14, 101 genes were up-regulated in absence of significant DNA copy number changes. Among these, the top-3 enriched functions (>30 fold, adj p < 0.05 comprised 7 genes coding for centralspindlin, chromosome passenger and minichromosome maintenance protein complexes. The genes Ccnb1 (Cyclin B1, Birc5 (Survivin, Nusap1 and Kif23 were the most recurrent in over a dozen GO terms related to the mitotic process. On the other hand, Pten plus the large non-coding RNAs Malat1 and Neat1 were among the 80 down-regulated genes with mRNA processing, nuclear bodies, ER-stress response and tumor suppression as relevant terms. Interestingly, the earliest discrete segmental aneuploidies arose by passage 18 in chromosomes 7, 10, 11, 13, 15, 17 and 19. By passage 23, when MOSE cells express the malignant phenotype, the dysregulated gene expression repertoire expanded, DNA imbalances enlarged in size and covered additional loci. Conclusion Prior to early aneuploidies, overexpression of genes coding for the mitotic apparatus in passage-14 pre-malignant MOSE cells indicate an increased proliferation rate suggestive of replicative stress. Concomitant down-regulation of nuclear bodies and RNA processing related genes

  6. OPIUM USE IN TRANSITIONAL CELL CARCINOMA OF THE URINARY BLADDER

    Directory of Open Access Journals (Sweden)

    A. Nourbakhsh

    2006-08-01

    Full Text Available Opium use is one of the most common forms of substance abuse in Iran and there are some evidence indicating it is a risk factor of transitional cell carcinoma (TCC of the urinary bladder. The majority of opium users are also cigarette smokers, so consideration of the high prevalence of smoking which is the most important risk factor of TCC of the urinary bladder among opium users is essential to assess the role of opium use as a possible risk factor of TCC. This study was done to evaluate the role of opium as a risk factor of TCC. A case-control study was performed on 255 individuals diagnosed with TCC of the urinary bladder by pathologic light microscopic examination of the tumor biopsies. Control population was chosen from individuals who had no history or presenting signs or symptoms of urinary problems. Case and control groups were matched by sex and age and also by cigarette smoking habits. Forty-one (18.1% of the cases and 12 (5% of controls were recognized to be opium users. Mantel-Haenszel analysis showed an odds ratio of 3.88, with 95% confidence interval of 1.99-7.57 and P value of < 0.001. Results indicate that opium use is a risk factor for TCC. The majority of opium users are also cigarette smokers, which is another important risk factor for TCC. Routine urine cytology and early evaluation in the patients presenting with any of the symptoms of urinary bladder malignancy by means of cystoscopy and urine cytology are highly recommended.

  7. The Immune System As a New Possible Cell Target for AFP 464 in a Spontaneous Mammary Cancer Mouse Model.

    Science.gov (United States)

    Callero, Mariana A; Rodriguez, Cristina E; Sólimo, Aldana; Bal de Kier Joffé, Elisa; Loaiza Perez, Andrea I

    2017-09-01

    Aminoflavone (AFP 464, NSC 710464), an antitumor agent which recently entered phase II clinical trials, acts against estrogen-positive breast cancer (ER+). AFP 464, which has a unique mechanism of action by activating aryl hydrocarbon receptor (AhR) signaling pathway, decreased tumor size, and growth rate in the estrogen dependent, Tamoxifen-sensitive spontaneous M05 mouse model. Considering that AhR has recently emerged as a physiological regulator of the innate and adaptive immune responses, we investigated whether AFP 464 modulates the immune response in our mouse model. Studies on the effect of AFP 464 on the immune system were carried in BALB/c mice bearing M05 semi-differentiated mammary adenocarcinomas that express estrogen and progesterone receptors. Splenic cells and tumor inflammatory infiltrates were studied by cytometric analyses. The modulation of splenocytes cytotoxic activity by AFP 464 was also evaluated. We further investigated the effects of AFP 464 on peritoneal macrophages by evaluating metalloproteinase, arginase, and iNOS activities. We found that AFP 464 increased splenic cytotoxic activity, diminished the number of systemic and local Treg lymphocytes, and MDSCs, and induced a M1 phenotype in peritoneal macrophages of M05 tumor bearing mice. Therefore, we conclude that AFP 464 modulates immune response which collaborates with its anti-tumor activity. Our results place the immune system as a novel target for this anti-cancer agent to strengthen the rationale for its inclusion in breast cancer treatment regimens. J. Cell. Biochem. 118: 2841-2849, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. Taurine and magnesium supplementation enhances the function of endothelial progenitor cells through antioxidation in healthy men and spontaneously hypertensive rats.

    Science.gov (United States)

    Katakawa, Mayumi; Fukuda, Noboru; Tsunemi, Akiko; Mori, Mari; Maruyama, Takashi; Matsumoto, Taro; Abe, Masanori; Yamori, Yukio

    2016-12-01

    Endothelial damage is repaired by endothelial progenitor cells (EPCs), which are pivotal in preventing cardiovascular diseases and prolonging lifespan. The WHO Cardiovascular Diseases and Alimentary Comparison Study demonstrated that dietary taurine and magnesium (Mg) intake suppresses cardiovascular diseases. We herein evaluate the effects of taurine and Mg supplementation on EPC function and oxidative stress in healthy men and spontaneously hypertensive rats (SHRs). Healthy men received taurine (3 g per day) or Mg (340 mg per day) for 2 weeks. SHRs and Wistar-Kyoto (WKY) rats were housed with high-salt drinking water (1% NaCl). The SHRs received 3% taurine solution and/or a high-Mg (600 mg per 100 g) diet for 4 weeks. Their peripheral blood mononuclear cells were separated to quantify EPC colony formation. Oxidative stress markers in their peripheral blood were evaluated using a free radical analytical system and a thiobarbituric acid reactive substance (TBARS) assay. Taurine and Mg supplementation significantly increased EPC colony numbers and significantly decreased free radical levels and TBARS scores in healthy men. Taurine and Mg supplementation significantly increased EPC colony numbers and significantly decreased TBARS scores and free radical levels in SHRs. Nicotinamide adenine dinucleotide phosphate oxidase component mRNA expression was significantly higher in the renal cortex of salt-loaded SHRs than in WKY rats, in which it was suppressed by taurine and Mg supplementation. Taurine and Mg supplementation increased EPC colony formation in healthy men and improved impaired EPC function in SHRs through antioxidation, indicating that the dietary intake of taurine and Mg may prolong lifespan by preventing the progression of cardiovascular diseases.

  9. Anterior gradient protein 2 expression in high grade head and neck squamous cell carcinoma correlated with cancer stem cell and epithelial mesenchymal transition.

    Science.gov (United States)

    Ma, Si-Rui; Wang, Wei-Ming; Huang, Cong-Fa; Zhang, Wen-Feng; Sun, Zhi-Jun

    2015-04-20

    Anterior gradient protein 2 (AGR2) is a novel biomarker with potential oncogenic role. We sought to investigate the diagnostic and prognostic role of AGR2 on head and neck squamous cell carcinoma (HNSCC) with an emphasis on its correlation of cancer stemloid cells (CSC) and epithelial mesenchymal transition (EMT). We found that AGR2 protein levels were higher in HNSCC than in normal oral mucosa. High levels of AGR2 were associated with the T category, pathological grade and lymph node metastasis of HNSCC. Expression of AGR2 increased in recurring HNSCC after radiotherapy and in post cisplatin-based chemotherapeutic tissues. In HNSCC cell lines, knock-down of AGR2 induced apoptosis, reduced sphere formation, and down-regulated Survivin, Cyclin D1, Bcl2, Bcl2l1, Slug, Snail, Nanog and Oct4. In addition, over-expressed AGR2 in transgenic mice with spontaneous HNSCC was associated with lost function of Tgfbr1 and/ or lost function of Pten. In vitro knockdown TGFBR1 in HNSCC cell lines increased AGR2 expression. These results suggest that AGR2 is involved in EMT and self-renewal of CSC and may present a potential therapeutic target (oncotarget) for HNSCC.

  10. Mesenchymal Stromal Cells Epithelial Transition Induced by Renal Tubular Cells-Derived Extracellular Vesicles.

    Directory of Open Access Journals (Sweden)

    Giulia Chiabotto

    Full Text Available Mesenchymal-epithelial interactions play an important role in renal tubular morphogenesis and in maintaining the structure of the kidney. The aim of this study was to investigate whether extracellular vesicles (EVs produced by human renal proximal tubular epithelial cells (RPTECs may induce mesenchymal-epithelial transition of bone marrow-derived mesenchymal stromal cells (MSCs. To test this hypothesis, we characterized the phenotype and the RNA content of EVs and we evaluated the in vitro uptake and activity of EVs on MSCs. MicroRNA (miRNA analysis suggested the possible implication of the miR-200 family carried by EVs in the epithelial commitment of MSCs. Bone marrow-derived MSCs were incubated with EVs, or RPTEC-derived total conditioned medium, or conditioned medium depleted of EVs. As a positive control, MSCs were co-cultured in a transwell system with RPTECs. Epithelial commitment of MSCs was assessed by real time PCR and by immunofluorescence analysis of cellular expression of specific mesenchymal and epithelial markers. After one week of incubation with EVs and total conditioned medium, we observed mesenchymal-epithelial transition in MSCs. Stimulation with conditioned medium depleted of EVs did not induce any change in mesenchymal and epithelial gene expression. Since EVs were found to contain the miR-200 family, we transfected MSCs using synthetic miR-200 mimics. After one week of transfection, mesenchymal-epithelial transition was induced in MSCs. In conclusion, miR-200 carrying EVs released from RPTECs induce the epithelial commitment of MSCs that may contribute to their regenerative potential. Based on experiments of MSC transfection with miR-200 mimics, we suggested that the miR-200 family may be involved in mesenchymal-epithelial transition of MSCs.

  11. Relaxor-ferroelectric crossover in (B i1 /2K1 /2)Ti O3 : Origin of the spontaneous phase transition and the effect of an applied external field

    Science.gov (United States)

    Hagiwara, Manabu; Ehara, Yoshitaka; Novak, Nikola; Khansur, Neamul H.; Ayrikyan, Azatuhi; Webber, Kyle G.; Fujihara, Shinobu

    2017-07-01

    The temperature evolution of polar order in an A -site complex perovskite (B i1 /2K1 /2)Ti O3 (BKT) has been investigated by measurements of dielectric permittivity, depolarization current, and stress-stain curves at elevated temperatures. Upon cooling from high temperatures, BKT first enters a relaxor state and then spontaneously transforms into a ferroelectric state. The analyses of temperature and frequency dependence of permittivity have revealed that polar nanoregions of the relaxor phase appear at temperatures higher than 560°C, and also that their freezing at 296°C triggers the spontaneous relaxor-ferroelectric transition. We discuss the key factors determining the development of long-range polar order in A -site complex perovskites through a comparison with the relaxor (B i1 /2N a1 /2)Ti O3 . We also show that application of biasing electric fields and compressive stresses to BKT favors its ferroelectric phase, resulting in a significant shift of the relaxor-ferroelectric transition temperature towards higher temperatures. Based on the obtained results, electric field-temperature and stress-temperature phase diagrams are firstly determined for BKT.

  12. Relationship between transit time and mechanical properties of a cell through a stenosed microchannel.

    Science.gov (United States)

    Ye, Ting; Shi, Huixin; Phan-Thien, Nhan; Lim, Chwee Teck; Li, Yu

    2018-01-24

    The changes in the mechanical properties of a cell are not only the cause of some diseases, but can also be a biomarker for some disease states. In recent times, microfluidic devices with built-in constrictions have been widely used to measure these changes. The transit time in such devices, defined as the time that a cell takes to pass through a constriction, has been found to be a crucial factor associated with the cell mechanical properties. Here, we use smoothed dissipative particle dynamics (SDPD), a particle-based numerical method, to explore the relationship between the transit time and mechanical properties of a cell. Three expressions of the transit time are developed from our simulation data, with respect to the stenosed size of constrictions, the shear modulus and bending modulus of cells, respectively. We show that a convergent constriction (the inlet is wider than the outlet), and a sharp-corner constriction (the constriction outlet is narrow) are better in identifying the differences in the transit time of cells. Moreover, the transit time increases and gradually approaches a constant as the shear modulus of cells increases, but increases first and then decreases as the bending modulus increases. These results suggest that the mechanical properties of cells can indeed be measured by analyzing their transit time, based on the recommended microfluidic device.

  13. Inhibitor production by normal rat tracheal epithelial cells influences the frequency of spontaneous and X-ray-induced enhanced growth variants

    International Nuclear Information System (INIS)

    Terzaghi-Howe, M.

    1989-01-01

    A cell culture model was used to assay for the induction of cell populations with enhanced growth capacity in culture in irradiated normal rat tracheal epithelial cells (NTEC). Some growth conditions appear to favor the proliferation of both normal and carcinogen-exposed populations, while others appear to select for populations previously exposed to carcinogen. In the present report we focus on what growth conditions are critical for controlling the emergence of spontaneous and X-ray induced proliferating epithelial foci (PEF) and what factor(s) directly influences the relative frequency of PEF in irradiated and control NTEC cultures. (author)

  14. Massachusetts Fuel Cell Bus Project: Demonstrating a Total Transit Solution for Fuel Cell Electric Buses in Boston

    Energy Technology Data Exchange (ETDEWEB)

    2017-05-22

    The Federal Transit Administration's National Fuel Cell Bus Program focuses on developing commercially viable fuel cell bus technologies. Nuvera is leading the Massachusetts Fuel Cell Bus project to demonstrate a complete transit solution for fuel cell electric buses that includes one bus and an on-site hydrogen generation station for the Massachusetts Bay Transportation Authority (MBTA). A team consisting of ElDorado National, BAE Systems, and Ballard Power Systems built the fuel cell electric bus, and Nuvera is providing its PowerTap on-site hydrogen generator to provide fuel for the bus.

  15. Sustained TL1A (TNFSF15) expression on both lymphoid and myeloid cells leads to mild spontaneous intestinal inflammation and fibrosis

    Science.gov (United States)

    Zheng, Libo; Zhang, Xiaolan; Chen, Jeremy; Ichikawa, Ryan; Wallace, Kori; Pothoulakis, Charalabos; Koon, Hon Wai

    2013-01-01

    TL1A is a member of the TNF superfamily, and its expression is increased in the mucosa of inflammatory bowel disease patients. Moreover, patients with certain TNFSF15 variants over-express TL1A and have a higher risk of developing strictures in the small intestine. Consistently, mice with sustained Tl1a expression in either lymphoid or myeloid cells develop spontaneous ileitis and increased intestinal collagen deposition. Transgenic (Tg) mice with constitutive Tl1a expression in both lymphoid and myeloid cells were generated to assess their in vivo consequence. Constitutive expression of Tl1a in both lymphoid and myeloid cells showed increased spontaneous ileitis and collagen deposition than WT mice. T cells with constitutive expression of Tl1a in both lymphoid and myeloid cells were found to have a more activated phenotype, increased gut homing marker CCR9 expression, and enhanced Th1 and Th17 cytokine activity than WT mice. Although no differences in T cell activation marker, Th1 or Th17 cytokine activity, ileitis, or collagen deposition were found between constitutive Tl1a expression in lymphoid only, myeloid only, or combined lymphoid and myeloid cells. Double hemizygous Tl1a-Tg mice appeared to have worsened ileitis and intestinal fibrosis. Our findings confirm that TL1A–DR3 interaction is involved in T cell-dependent ileitis and fibrosis. PMID:23638306

  16. The psychosocial transition associated with spontaneous 46,XX primary ovarian insufficiency: illness uncertainty, stigma, goal flexibility, and purpose in life as factors in emotional health.

    Science.gov (United States)

    Davis, Mary; Ventura, June L; Wieners, Mary; Covington, Sharon N; Vanderhoof, Vien H; Ryan, Mary E; Koziol, Deloris E; Popat, Vaishali B; Nelson, Lawrence M

    2010-05-01

    To examine factors associated with emotional well-being in women with spontaneous primary ovarian insufficiency. Cross-sectional and case-control study. Clinical research center, national U.S. health research facility. Women diagnosed with spontaneous 46,XX primary ovarian insufficiency (n = 100) at a mean age of 32.4 years and healthy control women of similar age (n = 60). Administration of validated self-reporting instruments. Illness uncertainty, stigma, goal disengagement/re-engagement, purpose in life, Positive and Negative Affect Schedule, Center of Epidemiologic Studies Depression Scale, State-Trait Anxiety Inventory. Compared with controls, women with spontaneous primary ovarian insufficiency scored adversely on all measures of affect. Illness uncertainty and purpose in life were significant independent factors associated with anxiety (R(2) = 0.47), stigma and purpose in life were the significant independent factors associated with depression (R(2) = 0.51), and goal re-engagement and purpose in life were significantly and independently associated with positive affect (R(2) = 0.43). This evidence supports the need for prospective studies. Our findings are consistent with the hypothesis that clinicians could improve the emotional well-being of their patients with primary ovarian insufficiency by [1] informing them better about their condition, [2] helping them to feel less stigmatized by the disorder, and [3] assisting them in developing alternative goals with regard to family planning as well as other goals. Published by Elsevier Inc.

  17. Mogoltacin enhances vincristine cytotoxicity in human transitional cell carcinoma (TCC) cell line.

    Science.gov (United States)

    Behnam Rassouli, F; Matin, M M; Iranshahi, M; Bahrami, A R; Neshati, V; Mollazadeh, S; Neshati, Z

    2009-03-01

    Bladder cancer is the second common cancer of the genitourinary system throughout the world and intravesical chemotherapy is usually used to reduce tumour recurrence and progression. Human transitional cell carcinoma (TCC) is an epithelial-like adherent cell line originally established from primary bladder carcinoma. Here we report the effect of mogoltacin, a sesquiterpene coumarin from Ferula badrakema on TCC cells. Mogoltacin was isolated from the fruits of F. badrakema, using silica gel column chromatography and preparative thin layer chromatography. Mogoltacin did not have any significant cytotoxicity effect on neoplastic TCC cells at 16, 32, 64, 128, 200 and 600 microg ml(-1) concentrations. In order to analyse its combination effect, TCC cells were cultured in the presence of various combining concentrations of mogoltacin and vincristine. Cells were then observed for morphological changes (by light microscopy) and cytotoxicity using MTT assay. The effect of mogoltacin on vincristine toxicity was studied after 24, 48 and 72 h of drug administration. The results of MTT assay showed that mogoltacin can significantly enhance the cytotoxicity of vincristine and confirmed the morphological observations. Results revealed that combination of 40 microg ml(-1) vincristine with 16 microg ml(-1) mogoltacin increased the cytotoxicity of vincristine after 48 h by 32.8%.

  18. Sustained TL1A (TNFSF15) expression on both lymphoid and myeloid cells leads to mild spontaneous intestinal inflammation and fibrosis

    OpenAIRE

    Zheng, Libo; Zhang, Xiaolan; Chen, Jeremy; Ichikawa, Ryan; Wallace, Kori; Pothoulakis, Charalabos; Koon, Hon Wai; Targan, Stephan R.; Shih, David Q.

    2013-01-01

    TL1A is a member of the TNF superfamily, and its expression is increased in the mucosa of inflammatory bowel disease patients. Moreover, patients with certain TNFSF15 variants over-express TL1A and have a higher risk of developing strictures in the small intestine. Consistently, mice with sustained Tl1a expression in either lymphoid or myeloid cells develop spontaneous ileitis and increased intestinal collagen deposition. Transgenic (Tg) mice with constitutive Tl1a expressio...

  19. Different expression of NOD2 in decidual stromal cells between normal and unexplained recurrent spontaneous abortion women during first trimester gestation

    OpenAIRE

    Zhang, Yuanyuan; Yang, Chunfeng; Fu, Shuai; Chen, Xin; Zhang, Shining; Li, Yiyang; Du, Meirong; Zhang, Jianping

    2014-01-01

    The NOD2 gene, encoding intracellular paternal recognition receptor (PRR) also called caspase activation and recruitment domain 15 (CARD15), is mutated in Crohn’s disease, an autoimmune-disorder. Unexplained recurrent spontaneous abortion (URSA) involved in complex auto-immune disorder. However, little is known about the expression of NOD2 protein at maternal-fetal interface with URSA patients. Our aim was to compare the expression levels of NOD2 in the decidual stromal cells (DSCs) from pati...

  20. Generation of Breast Cancer Stem Cells through Epithelial-Mesenchymal Transition

    OpenAIRE

    Morel, Anne-Pierre; Lièvre, Marjory; Thomas, Clémence; Hinkal, George; Ansieau, Stéphane; Puisieux, Alain

    2008-01-01

    Recently, two novel concepts have emerged in cancer biology: the role of so-called "cancer stem cells" in tumor initiation, and the involvement of an epithelial-mesenchymal transition (EMT) in the metastatic dissemination of epithelial cancer cells. Using a mammary tumor progression model, we show that cells possessing both stem and tumorigenic characteristics of "cancer stem cells" can be derived from human mammary epithelial cells following the activation of the Ras-MAPK pathway. The acquis...

  1. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2015

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gikakis, Christina [Federal Transit Administration, Washington, DC (United States)

    2015-12-11

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. Various stakeholders, including FCEB developers, transit agencies, and system integrators, have expressed the value of this annual status report, which provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. The annual status report tracks the progress of the FCEB industry toward meeting technical targets, documents the lessons learned, and discusses the path forward for commercial viability of fuel cell technology for transit buses. The 2015 summary results primarily focus on the most recent year for each demonstration, from August 2014 through July 2015. The results for these buses account for more than 1,045,000 miles traveled and 83,000 hours of fuel cell power system operation. The primary results presented in the report are from two demonstrations of fuel-cell-dominant bus designs: the Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California and the American Fuel Cell Bus Project at SunLine Transit Agency in California.

  2. [Influence of hepatocyte cell adhesion molecule on gene expression profile of human bladder transitional cell carcinoma cell line].

    Science.gov (United States)

    Wang, Qiu-ju; Lv, Chang-kun; Tao, Jia; Du, Hong-fei; Fan, Yan-ru; Song, Xue-dong; Luo, Chun-li

    2013-04-01

    To investigate the changes of gene expression file in transitional cell carcinoma of bladder after hepatocyte cell adhesion molecule(hepaCAM) overexpression. Affymetrix Human Genome U133 Plus 2.0 Array was used to investigate the changes of gene expression profile between adenovirus-green fluorescent protein(GFP) -hepaCAM group and GFP group in transitional cell carcinoma of bladder EJ cells.Significant Analysis of Microarray(SAM) was used to screen the differentially expressed genes, DAVID software was used to conduct gene ontology analysis and wikiPathway analysis based on the differentially expressed genes. Reverse transcription-polymerase chain reaction and Western blot were applied to verify microarray data. Compared with the GFP group, a total of 2469 genes were up-regulated or down-regulated by more than 2 times in the GFP-hepaCAM group. Among these genes, 1602 genes were up-regulated and 867 were down-regulated.Most of the differentially expressed genes were involved in the function of cell proliferation and cell cycle regulation. The mRNA expressions of nibrin, liver kinase B1, and cyclin D1 detected by reverse transcription-polymerase chain reaction in three different bladder cancer cell lines were consistent with the microarray data.The protein expressions of nibrin and liver kinase B1 in these three cell lines measured by Western blot were consistent with the mRNA expression. HepaCAM can alter the gene expression profile of bladder cancer EJ cells. The well-known anti-tumor effect of hepaCAM may be mediated by regulating the gene expression via multiple pathways.

  3. Asymmetric Freedericksz transitions from symmetric liquid crystal cells doped with harvested ferroelectric nanoparticles.

    Science.gov (United States)

    Cook, G; Reshetnyak, V Yu; Ziolo, R F; Basun, S A; Banerjee, P P; Evans, D R

    2010-08-02

    The electrical Freedericksz transition characteristics of planar aligned liquid crystal cells doped with harvested single ferroelectric domain 9 nm nanoparticles of BaTiO(3) have been measured. We demonstrate for the first time that the electrical pre-history of the cells imparts significant polarity sensitivity to the Freedericksz characteristics. The presence of harvested single domain ferroelectric nanoparticles enables cells to be programmably semi-permanently polarized. This reduces or increases the Freedericksz transition threshold by 0.8 V, depending on the polarity of the applied voltage, giving a net 1.6 V Freedericksz threshold asymmetry for 8 mum thick cells filled with TL205 liquid crystal.

  4. Transcriptional regulation is a major controller of cell cycle transition dynamics

    DEFF Research Database (Denmark)

    Romanel, Alessandro; Jensen, Lars Juhl; Cardelli, Luca

    2012-01-01

    DNA replication, mitosis and mitotic exit are critical transitions of the cell cycle which normally occur only once per cycle. A universal control mechanism was proposed for the regulation of mitotic entry in which Cdk helps its own activation through two positive feedback loops. Recent discoveries...... in various organisms showed the importance of positive feedbacks in other transitions as well. Here we investigate if a universal control system with transcriptional regulation(s) and post-translational positive feedback(s) can be proposed for the regulation of all cell cycle transitions. Through...

  5. Imaging of transitional cell carcinomas of the urinary tracts

    International Nuclear Information System (INIS)

    Ozmen, M.

    2012-01-01

    Full text: Transitional cell carcinoma (TCC) is the most common urothelial neoplasm to involve the upper urinary tract and bladder. Prognosis significantly worsens with deeper invasion. The role of imaging is to detect the tiniest urothelial neoplasms while still potentially resectable and curable. In case of advance disease, imaging should identify the extent of disease. Intravenous or retrograde urography, ultrasonography, computed tomography or magnetic resonance imaging have been used for diagnosis of TCC. The diagnostic performances of these imaging modalities differ from each other. A recent review regarding imaging of TCC by Razavi et al states that the retrieved sensitivity/specificity for the detection of TCC of upper urinary tract for CT urography (CTU), MR urography, excretory urography, and retrograde urography were 96%/99%, 69%/97%, 80%/81%, and 96%/96%, respectively. For detecting bladder cancer, the retrieved sensitivity/specificity for CT cystography, MR cystography, and ultrasonography were 94%/98%, 91%/95%, and 78%/96%, respectively. They conclude that CT urography is the best imaging technique for confirming or excluding malignancy in the upper urinary tract, whereas CT cystography has the best diagnostic performance for diagnosing bladder cancer. While cystoscopy is still considered by most to be the gold-standard for evaluation of the urinary bladder, CTU is playing an increasing role in the detection of urinary bladder urothelial neoplasms. As with the upper urinary tract, bladder urothelial neoplasms typically present as a filling defect, a focal mass, or an area of abnormal focal wall thickening. Magnetic resonance imaging is superior for evaluation of the depth of tumour invasion into the bladder wall, but this knowledge may not ultimately affect treatment as feasibility for radical cystectomy depends on staging by a combination of clinical, histopathological and imaging findings. Radical cystectomy may include resection of adjacent organs

  6. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2016

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jeffers, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-11-01

    This report, published annually, summarizes the progress of fuel cell electric bus development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. Funding for this effort is provided by the U.S. Department of Energy's Fuel Cell Technologies Office within the Office of Energy Efficiency and Renewable Energy and by the U.S. Department of Transportation's Federal Transit Administration. The 2016 summary results primarily focus on the most recent year for each demonstration, from August 2015 through July 2016. The results for these buses account for more than 550,000 miles traveled and 59,500 hours of fuel cell power system operation. The primary results presented in the report are from three demonstrations of two different fuel-cell-dominant bus designs: Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California; American Fuel Cell Bus Project at SunLine Transit Agency in California; and American Fuel Cell Bus Project at the University of California at Irvine.

  7. Endothelial-mesenchymal transition and its contribution to the emergence of stem cell phenotype

    Science.gov (United States)

    Medici, Damian; Kalluri, Raghu

    2012-01-01

    Vascular endothelial cells can demonstrate considerable plasticity to generate other cell types during embryonic development and disease progression. This process occurs through a cell differentiation mechanism known as endothelial-mesenchymal transition (EndMT). The generation of mesenchymal cells from endothelium is a crucial step in endothelial cell differentiation to several lineages including fibroblasts, myofibroblasts, mural cells, osteoblasts, chondrocytes, and adipocytes. Such differentiation patterns have been observed in systems of cardiac development, fibrosis, diabetic nephropathy, heterotopic ossification and cancer. Here we describe the EndMT program and discuss the current evidence of EndMT-mediated acquisition of stem cell characteristics and multipotent differentiation capabilities. PMID:22554794

  8. Variations in T-helper 17 and Regulatory T Cells during The Menstrual Cycle in Peripheral Blood of Women with Recurrent Spontaneous Abortion

    Directory of Open Access Journals (Sweden)

    Nasrin Sereshki

    2014-03-01

    Full Text Available Background: Disorders in immune system regulation may result in pregnancy abnormalities such as recurrent spontaneous abortion (RSA. This study aims to determine the ratio of regulatory T (Treg and T helper (Th 17 cells in unexplained RSA (URSA women during proliferative and secretory phases of their menstrual cycles compared to healthy non-pregnant women. Materials and Methods: In this case control study, 25 women with URSA and 35 healthy, non-pregnant women were enrolled. The percentage of Th17 and Treg cells in participants peripheral blood were determined by flow cytometry. Results: The percentage of Th17 cells and their related cytokines in serum (IL-17A were higher in the proliferative and secretory phases of the menstrual cycles of URSA women compared to the control women. However, a lower percentage of Treg cells and their related cytokines in serum, transforming growth factor (TGF β1 and interleukin (IL-10 were detected in the proliferative but not the secretory phase of the URSA group. The ratio of Th17/CD4+ Treg was higher in the URSA group than the control group. We observed an increased ratio of Th17/CD4+ Treg during the proliferative and secretory phases in URSA women. Conclusion: The imbalance between Th17 and Treg cells during the proliferative phase of menstrual cycles in the URSA group may be considered a cause for spontaneous abortion.

  9. Dentate gyrus progenitor cell proliferation after the onset of spontaneous seizures in the tetanus toxin model of temporal lobe epilepsy

    Czech Academy of Sciences Publication Activity Database

    Jiruška, Přemysl; Shtaya, A.B.Y.; Bodansky, D.M.S.; Chang, W.C.; Gray, W.P.; Jefferys, J. G. R.

    2013-01-01

    Roč. 54, Jun 2013 (2013), s. 492-498 ISSN 0969-9961 R&D Projects: GA ČR(CZ) GAP303/10/0999 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : spontaneous seizures * temporal lobe epilepsy * neurogenesis * tetanus toxin * apoptosis Subject RIV: FH - Neurology Impact factor: 5.202, year: 2013

  10. Effects of calcitriol, seocalcitol, and medium-chain triglyceride on a canine transitional cell carcinoma cell line

    DEFF Research Database (Denmark)

    Kaewsakhorn, T.; Kisseberth, W.C.; Capen, C.C.

    2005-01-01

    Background: Transitional cell carcinoma (TCC) in dogs is associated with high morbidity and mortality. Calcitriol and its analog seocalcitol, combined with medium-chain triglyceride (MCT), have potential for the treatment of this disease. Materials and Methods: TCC cells were treated with calcitr...

  11. Wnt is necessary for mesenchymal to epithelial transition in colorectal cancer cells.

    Science.gov (United States)

    Schwab, Renate H M; Amin, Nancy; Flanagan, Dustin J; Johanson, Timothy M; Phesse, Toby J; Vincan, Elizabeth

    2018-03-01

    Metastasis underlies most colorectal cancer mortality. Cancer cells spread through the body as single cells or small clusters of cells that have an invasive, mesenchymal, nonproliferative phenotype. At the secondary site, they revert to a proliferative "tumor constructing" epithelial phenotype to rebuild a tumor. We previously developed a unique in vitro three-dimensional model, called LIM1863-Mph, which faithfully recapitulates these reversible transitions that underpin colorectal cancer metastasis. Wnt signaling plays a key role in these transitions and is initiated by the coupling of extracellular Wnt to Frizzled (FZD). Using the LIM1863-Mph model system we demonstrated that the Wnt receptor FZD7 is necessary for mesenchymal to epithelial transition (MET). Here we investigate the role of Wnt in MET. Wnt secretion is dependent on palmitoylation by Porcupine (PORC). A PORC inhibitor (IWP2) that prevents Wnt secretion, blocked the epithelial transition of mesenchymal LIM1863-Mph cells. Wnt gene array analysis identified several Wnts that are upregulated in epithelial compared with mesenchymal LIM1863-Mph cells, suggesting these ligands in MET. Wnt2B was the most abundant differentially expressed Wnt gene. Indeed, recombinant Wnt2B could overcome the IWP2-mediated block in epithelial transition of mesenchymal LIM1863-Mph cells. Wnt2B co-operates with Frizzled7 to mediate MET in colorectal cancer. Developmental Dynamics 247:521-530, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  12. Involvement of cyclic nucleotide-gated channels in spontaneous activity generated in isolated interstitial cells of Cajal from the rabbit urethra.

    Science.gov (United States)

    Sancho, Maria; Bradley, Eamonn; Garcia-Pascual, Angeles; Triguero, Domingo; Thornbury, Keith D; Hollywood, Mark A; Sergeant, Gerard P

    2017-11-05

    Cyclic nucleotide-gated (CNG) channels are non-selective cation channels that mediate influx of extracellular Na + and Ca 2+ in various cell types. L-cis-Diltiazem, a CNG channel blocker, inhibits contraction of urethral smooth muscle (USM), however the mechanisms underlying this effect are still unclear. We investigated the possibility that CNG channels contribute to spontaneous pacemaker activity in freshly isolated interstitial cells of Cajal (ICC) isolated from the rabbit urethra (RUICC). Using immunocytochemistry, we found intense CNG1-immunoreactivity in vimentin-immunoreactive RUICC, mainly within patches of the cellular body and processes. In contrast, α-actin immunoreactive smooth muscle cells (SMC) did not show significant reactivity to a specific CNGA1 antibody. Freshly isolated RUICC, voltage clamped at -60mV, developed spontaneous transient inward currents (STICs) that were inhibited by L-cis-Diltiazem (50µM). Similarly, L-cis-Diltiazem (50µM) also inhibited Ca 2+ waves in isolated RUICC, recorded using a Nipkow spinning disk confocal microscope. L-cis-Diltiazem (50µM) did not affect caffeine (10mM)-induced Ca 2+ transients, but significantly reduced phenylephrine-evoked Ca 2+ oscillations and inward currents in in RUICC. L-type Ca 2+ current amplitude in isolated SMC was reduced by ~18% in the presence of L-cis-Diltiazem (50µM), however D-cis-Diltiazem, a recognised L-type Ca 2+ channel blocker, abolished L-type Ca 2+ current but did not affect Ca 2+ waves or STICs in RUICC. These results indicate that the effects of L-cis-diltiazem on rabbit USM could be mediated by inhibition of CNG1 channels that are present in urethral ICC and therefore CNG channels contribute to spontaneous activity in these cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Research of TGF-beta1 Inducing Lung Adencarcinoma PC9 Cells to Mesenchymal Cells Transition

    Directory of Open Access Journals (Sweden)

    Xiaofeng CHEN

    2010-01-01

    Full Text Available Background and objective It has been proven that epithelial-mesenchymal transition (EMT not only correlated with embryonic development but also could promote tumor invasion and metastasis. Transforming growth factor beta-1 (TGF-β1 has been identified as the main inducer of tumor EMT. The aim of this study was to investigate the effects of TGF-β1 on EMT and PI3K/AKT signaling pathway in lung adencarcinoma PC9 cells. Methods Cultured PC9 cells were treated with different concentrations of TGF-β1 for 48 h. The morphological changes were observed under phase-contrast microscopy; EMT relative marker protein changes were assessed by Western blot and immunoflurescence staining. In addition, the expression of AKT and P-AKT were also measured by Western blot. Results The data showed that TGF-β1 could induce PC9 morphological alteration from epithelial to mesenchymal and upregulate the expression of mesenchymal maker protein Fibronectin. Obviously, the expression of P-AKT was downregulated by TGF-β1 treatment for 48 h. Conclusion TGF-β1 might induce EMT of PC9 cells , accompanied by the changes of PI3K/AKT signaling pathway.

  14. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2013

    Science.gov (United States)

    2013-12-01

    This report is the seventh in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. This r...

  15. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2012

    Science.gov (United States)

    2012-11-12

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The repo...

  16. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2011

    Science.gov (United States)

    2011-11-11

    his report is the fifth in a series of annual status reports that summarize the progress resulting from fuel cell transit bus demonstrations in the United States and provide a discussion of the achievements and challenges of fuel cell propulsion in t...

  17. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chandler, Kevin [Battelle, Columbus, OH (United States); Gikakis, Christina [Federal Transit Administration, Washington, DC (United States)

    2012-11-01

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results over the last year.

  18. Dispersed cells represent a distinct stage in the transition from bacterial biofilm to planktonic lifestyles

    DEFF Research Database (Denmark)

    Chua, Song Lin; Liu, Yang; Yam, Joey Kuok Hoong

    2014-01-01

    Bacteria assume distinct lifestyles during the planktonic and biofilm modes of growth. Increased levels of the intracellular messenger c-di-GMP determine the transition from planktonic to biofilm growth, while a reduction causes biofilm dispersal. It is generally assumed that cells dispersed from......-dispersing agent, an iron chelator and tobramycin efficiently reduces the survival of the dispersed cells....

  19. Loss of prostasin (PRSS8 in human bladder transitional cell carcinoma cell lines is associated with epithelial-mesenchymal transition (EMT

    Directory of Open Access Journals (Sweden)

    Chai Karl X

    2009-10-01

    Full Text Available Abstract Background The glycosylphosphatidylinositol (GPI-anchored epithelial extracellular membrane serine protease prostasin (PRSS8 is expressed abundantly in normal epithelia and essential for terminal epithelial differentiation, but down-regulated in human prostate, breast, and gastric cancers and invasive cancer cell lines. Prostasin is involved in the extracellular proteolytic modulation of the epidermal growth factor receptor (EGFR and is an invasion suppressor. The aim of this study was to evaluate prostasin expression states in the transitional cell carcinomas (TCC of the human bladder and in human TCC cell lines. Methods Normal human bladder tissues and TCC on a bladder cancer tissue microarray (TMA were evaluated for prostasin expression by means of immunohistochemistry. A panel of 16 urothelial and TCC cell lines were evaluated for prostasin and E-cadherin expression by western blot and quantitative PCR, and for prostasin gene promoter region CpG methylation by methylation-specific PCR (MSP. Results Prostasin is expressed in the normal human urothelium and in a normal human urothelial cell line, but is significantly down-regulated in high-grade TCC and lost in 9 (of 15 TCC cell lines. Loss of prostasin expression in the TCC cell lines correlated with loss of or reduced E-cadherin expression, loss of epithelial morphology, and promoter DNA hypermethylation. Prostasin expression could be reactivated by demethylation or inhibition of histone deacetylase. Re-expression of prostasin or a serine protease-inactive variant resulted in transcriptional up-regulation of E-cadherin. Conclusion Loss of prostasin expression in bladder transitional cell carcinomas is associated with epithelial-mesenchymal transition (EMT, and may have functional implications in tumor invasion and resistance to chemotherapy.

  20. Characterization of the subsets of human NKT-like cells and the expression of Th1/Th2 cytokines in patients with unexplained recurrent spontaneous abortion.

    Science.gov (United States)

    Yuan, Jing; Li, Jian; Huang, Shi-Yun; Sun, Xin

    2015-08-01

    The objective was to investigate the subsets of natural killer T (NKT)-like cells and the expression of Th1/Th2 cytokines in the peripheral blood (PB) and/or decidual tissue of patients with unexplained recurrent spontaneous abortion (URSA). The percentages of NKT-like cells in the PB and deciduas of URSA patients in early pregnancy and in the PB of nonpregnant women were analyzed by flow cytometry. The expression of interferon (IFN)-γ (Th1 cytokine) and Th2 cytokines, interleukin (IL)-4 and IL-10, in the PB and decidual tissue was measured by quantitative RT-PCR and enzyme-linked immunosorbent assay (ELISA). Most percentages of subsets of NKT-like cells (CD3(+)CD56(+), CD3(+)CD56(+)CD16(+)) in the PB and deciduas were significantly greater in URSA patients than in normal pregnant and nonpregnant women. A cut-off value of 3.75% for the increased percentage of CD3(+)CD56(+)CD16(+) NKT-like cells in the PB appeared to be predictive of pregnancy failure. Moreover, we found that in the decidua, IFN-γ expression was significantly higher, while IL-4 and IL-10 expression was significantly lower in URSA patients compared with those with a normal pregnancy. The ratio of decidual Th1/Th2 cytokines in URSA patients was significantly increased compared with that in normal pregnant women. Decidual IL-4 expression correlated negatively with the percentages of blood CD3(+)CD56(+)CD16(+) NKT-like cells and the decidual CD3(+)CD56(+) and CD3(+)CD56(+)CD16(+) NKT-like cells. NKT-like cells may play an important role in maintaining normal pregnancy. Measurement of CD3(+)CD56(+)CD16(+) NKT-like cells in the PB may provide a potential tool for assessing patients' risk of spontaneous abortion. Copyright © 2015. Published by Elsevier Ireland Ltd.

  1. TOLERABILITY AND TUMOR RESPONSE OF A NOVEL LOW-DOSE PALLIATIVE RADIATION THERAPY PROTOCOL IN DOGS WITH TRANSITIONAL CELL CARCINOMA OF THE BLADDER AND URETHRA.

    Science.gov (United States)

    Choy, Kevin; Fidel, Janean

    2016-05-01

    Previously reported radiation protocols for transitional cell carcinoma of the canine lower urinary tract have been ineffective or associated with increased side effects. Objectives of this retrospective, cross-sectional study were to describe safety of and tumor responses for a novel palliative radiation protocol for transitional cell carcinoma in dogs. Included dogs had cytologically or histologically confirmed transitional cell carcinoma of the bladder or urethra, and were treated with 10 once-daily fractions (Monday-Friday) of 2.7 Gy. Thirteen dogs were sampled, with six treated using radiation as first-line (induction) therapy and seven treated using radiation as rescue therapy after failing previous chemotherapy. Within 6 weeks of radiation, 7.6% (1/13) dogs had a complete response, 53.8% (7/13) partial response, 38.5% (5/13) stable disease, and none had progressive disease. Three patients presenting with urethral obstruction had spontaneous micturition restored during the treatment protocol. A single patient with unilateral ureteral obstruction was patent at recheck examination. Median survival time from time of initial diagnosis was 179 days. Median survival time from start of radiation was 150 days. Acute radiation side effects occurred in 31% (4/13) patients and were classified as grade 1 or 2. No significant late side radiation side effects were reported. No variables examined were identified as prognostic factors. Findings indicated that the reported radiation protocol was safe in this sample of dogs with bladder and urethral transitional cell carcinoma. Future prospective studies are needed to determine utility of this treatment as a rescue therapy in patients with complete urinary tract obstruction. © 2016 American College of Veterinary Radiology.

  2. Effects of misoprostol on cell migration and transit in the dog stomach

    International Nuclear Information System (INIS)

    Goodlad, R.A.; Madgwick, A.J.; Moffatt, M.R.; Levin, S.; Allen, J.L.; Wright, N.A.

    1990-01-01

    Prostaglandins of the E series increase stomach mucosal mass by inducing hyperplasia, which could be the result either of increased cell production or of decreased cell loss. This report describes an investigation of the effect of the prostaglandin E1 analogue, misoprostol, on cell migration and transit. 3H-thymidine was used to label those cells synthesizing deoxyribonucleic acid in dogs that had been given an oral dose of 300 micrograms/kg per day misoprostol for 11 weeks. The animals were killed at timed intervals, and tissue from the gastric fundus was prepared for autoradiography. The distribution of labeled cells at various times after labeling was used to follow the movement of the wave of label and to calculate median cell migration rates and transit times. The migration rate of cells toward the gastric lumen was significantly increased from 1.4 +/- 0.3 to 3.6 +/- 0.6 cell positions per day in the misoprostol-treated group (p less than 0.001); however, the gland length (from the most basal mucous neck cell to the luminal surface) was also increased (from 52.1 +/- 1.1 to 74.0 +/- 1.6; p less than 0.001), thus there was no significant difference in the (transit) time taken for cells to reach the top of the gland (control, 17.5 +/- 9.8 days; test, 12.2 +/- 7.1 days)

  3. Effects of misoprostol on cell migration and transit in the dog stomach

    Energy Technology Data Exchange (ETDEWEB)

    Goodlad, R.A.; Madgwick, A.J.; Moffatt, M.R.; Levin, S.; Allen, J.L.; Wright, N.A. (Imperial Cancer Research Fund, London (England))

    1990-01-01

    Prostaglandins of the E series increase stomach mucosal mass by inducing hyperplasia, which could be the result either of increased cell production or of decreased cell loss. This report describes an investigation of the effect of the prostaglandin E1 analogue, misoprostol, on cell migration and transit. 3H-thymidine was used to label those cells synthesizing deoxyribonucleic acid in dogs that had been given an oral dose of 300 micrograms/kg per day misoprostol for 11 weeks. The animals were killed at timed intervals, and tissue from the gastric fundus was prepared for autoradiography. The distribution of labeled cells at various times after labeling was used to follow the movement of the wave of label and to calculate median cell migration rates and transit times. The migration rate of cells toward the gastric lumen was significantly increased from 1.4 +/- 0.3 to 3.6 +/- 0.6 cell positions per day in the misoprostol-treated group (p less than 0.001); however, the gland length (from the most basal mucous neck cell to the luminal surface) was also increased (from 52.1 +/- 1.1 to 74.0 +/- 1.6; p less than 0.001), thus there was no significant difference in the (transit) time taken for cells to reach the top of the gland (control, 17.5 +/- 9.8 days; test, 12.2 +/- 7.1 days).

  4. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2017

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew B [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-11-21

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of results from evaluations performed by the National Renewable Energy Laboratory. This annual status report combines results from all FCEB demonstrations, tracks the progress of the FCEB industry toward meeting technical targets, documents the lessons learned, and discusses the path forward for commercial viability of fuel cell technology for transit buses. These data and analyses help provide needed information to guide future early-stage research and development. The 2017 summary results primarily focus on the most recent year for each demonstration, from August 2016 through July 2017. The primary results presented in the report are from five demonstrations of two different fuel-cell-dominant bus designs: Zero Emission Bay Area Demonstration Group led by Alameda-Contra Costa Transit District (AC Transit) in California; American Fuel Cell Bus (AFCB) Project at SunLine Transit Agency in California; AFCB Project at the University of California at Irvine; AFCB Project at Orange County Transportation Authority; and AFCB Project at Massachusetts Bay Transportation Authority.

  5. Tumor Budding Cells, Cancer Stem Cells and Epithelial-Mesenchymal Transition-type Cells in Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Eva eKaramitopoulou

    2013-01-01

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4 and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with WNT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial-mesenchymal transition (EMT. Emerging evidence has demonstrated that cancer stem cells (CSCs, small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5 of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric and ampullary carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs and EMT-type cells in PDAC.

  6. Animal model of naturally occurring bladder cancer: Characterization of four new canine transitional cell carcinoma cell lines

    OpenAIRE

    Rathore, Kusum; Cekanova, Maria

    2014-01-01

    Background Development and further characterization of animal models for human cancers is important for the improvement of cancer detection and therapy. Canine bladder cancer closely resembles human bladder cancer in many aspects. In this study, we isolated and characterized four primary transitional cell carcinoma (K9TCC) cell lines to be used for future in vitro validation of novel therapeutic agents for bladder cancer. Methods Four K9TCC cell lines were established from naturally-occurring...

  7. Transitioning adolescents with sickle cell disease to adult-centered care.

    Science.gov (United States)

    Hauser, E S; Dorn, L

    1999-01-01

    Efforts have been made to formalize transitioning of adolescents with chronic health conditions such as sickle cell disease (SCD), from child-centered care (CCC) to adult-centered care (ACC). A dearth of literature exists that examines the transition of adolescents with SCD or offers guidance for transitioning. This study sought to explore concerns, expectations, and needs regarding the transition from CCC to ACC and to generate a framework for transitioning. Separate focus groups were conducted with adolescents (n = 22), their parents (n = 22), and practitioners (n = 8). Focus group interviews revealed that concerns, expectations, and needs for adolescents and their parents were parallel. Adolescents and their parents had concerns about: (a) leaving a familiar setting and physician whom they trusted, (b) going to an adult provider who may or may not be familiar with managing sickle cell disease, and (c) establishing new family roles. Practitioners affirm the need for transitioning that prepares the adolescents and their families for ACC. Findings led to a draft framework for transitioning that which will be tested at a later date. The framework is based on an ecological perspective that includes physiologic, developmental and psychosocial, and educational/vocational components.

  8. Oct-4 and Nanog promote the epithelial-mesenchymal transition of breast cancer stem cells and are associated with poor prognosis in breast cancer patients

    Science.gov (United States)

    Luo, Minna; Zhang, Xin; Wei, Xiaofei; Gao, Jiyue; Zhao, Zuowei; Liu, Caigang

    2014-01-01

    Oct-4 and Nanog in regulating the epithelial-mesenchymal transition (EMT) and metastasis of breast cancer has not been clarified. We found that both Oct-4 and Nanog expression were significantly associated with tumor pathology and poor prognosis in 126 breast cancer patients. Characterization of CD44+CD24-Cancer stem cell(CSC) derived from breast cancer cells indicated that CSC rapidly formed mammospheres and had potent tumorigenicity in vivo. Furthermore, TGF-β up-regulated the expression of Oct-4, Nanog, N-cadherin, vimentin, Slug, and Snail, but down-regulated E-cadherin and cytokeratin 18 expression, demonstrating that CSC underwent EMT. Knockdown of both Oct-4 and Nanog expression inhibited spontaneous changes in the expression of EMT-related genes, while induction of both Oct-4 and Nanog over-expression enhanced spontaneous changes in the expression of EMT-related genes in CSC. However, perturbing alternation of Oct-4 and Nanog expression also modulated TGF-β-induced EMT-related gene expression in CSC. Induction of Oct-4 and Nanog over-expression enhanced the invasiveness of CSC, but knockdown of both Oct-4 and Nanog inhibited the migration of CSC in vitro. Our data suggest that both Oct-4 and Nanog may serve as biomarkers for evaluating breast cancer prognosis. Our findings indicate that Oct-4 and Nanog positively regulate the EMT process, contributing to breast cancer metastasis. PMID:25301732

  9. Transit-amplifying cells orchestrate stem cell activity and tissue regeneration.

    Science.gov (United States)

    Hsu, Ya-Chieh; Li, Lishi; Fuchs, Elaine

    2014-05-08

    Transit-amplifying cells (TACs) are an early intermediate in tissue regeneration. Here, using hair follicles (HFs) as a paradigm, we show that emerging TACs constitute a signaling center that orchestrates tissue growth. Whereas primed stem cells (SCs) generate TACs, quiescent SCs only proliferate after TACs form and begin expressing Sonic Hedgehog (SHH). TAC generation is independent of autocrine SHH, but the TAC pool wanes if they can't produce SHH. We trace this paradox to two direct actions of SHH: promoting quiescent-SC proliferation and regulating dermal factors that stoke TAC expansion. Ingrained within quiescent SCs' special sensitivity to SHH signaling is their high expression of GAS1. Without sufficient input from quiescent SCs, replenishment of primed SCs for the next hair cycle is compromised, delaying regeneration and eventually leading to regeneration failure. Our findings unveil TACs as transient but indispensable integrators of SC niche components and reveal an intriguing interdependency of primed and quiescent SC populations on tissue regeneration. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Kaempferol modulates the metastasis of human non-small cell lung cancer cells by inhibiting epithelial-mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Meng Hang

    2015-06-01

    Full Text Available The present study was done to determine whether kaempferol, a natural polyphenol of the flavonoid family, affects Epithelial-Mesenchymal Transition (EMT in non-small cell lung cancer cells. Kaempferol not only inhibited cancer cell proliferation and migration in a dose-dependent manner but also modulated the expression of EMT-related proteins E-cadherin and vimentin which are indispensible to cellular motility, invasiveness and metastasis. These results indicate that kaempferol suppresses non-small cell lung cancer migration by modulating the expression of EMT proteins. Therefore, kaempferol may be useful as a potential anticancer agent for non-small cell lung cancer.

  11. Healthy human CSF promotes glial differentiation of hESC-derived neural cells while retaining spontaneous activity in existing neuronal networks

    Directory of Open Access Journals (Sweden)

    Heikki Kiiski

    2013-05-01

    The possibilities of human pluripotent stem cell-derived neural cells from the basic research tool to a treatment option in regenerative medicine have been well recognized. These cells also offer an interesting tool for in vitro models of neuronal networks to be used for drug screening and neurotoxicological studies and for patient/disease specific in vitro models. Here, as aiming to develop a reductionistic in vitro human neuronal network model, we tested whether human embryonic stem cell (hESC-derived neural cells could be cultured in human cerebrospinal fluid (CSF in order to better mimic the in vivo conditions. Our results showed that CSF altered the differentiation of hESC-derived neural cells towards glial cells at the expense of neuronal differentiation. The proliferation rate was reduced in CSF cultures. However, even though the use of CSF as the culture medium altered the glial vs. neuronal differentiation rate, the pre-existing spontaneous activity of the neuronal networks persisted throughout the study. These results suggest that it is possible to develop fully human cell and culture-based environments that can further be modified for various in vitro modeling purposes.

  12. miR-520 promotes DNA-damage-induced trophoblast cell apoptosis by targeting PARP1 in recurrent spontaneous abortion (RSA).

    Science.gov (United States)

    Dong, Xiujuan; Yang, Long; Wang, Hui

    2017-04-01

    The establishment and maintenance of successful pregnancy mainly depends on trophoblast cells. Their dysfunction has been implicated in recurrent spontaneous abortion (RSA), a major complication of pregnancy. However, the underlying mechanisms of trophoblasts dysfunction remain unclear. DNA-damage-induced cell apoptosis has been reported to play a vital role in cell death. In this study, we identified a novel microRNA (miR-520) in RSA progression via regulating trophoblast cell apoptosis. Microarray analysis showed that miR-520 was highly expressed in villus of RSA patients. By using flow cytometry analysis, we observed miR-520 expression was correlated with human trophoblast cell apoptosis in vitro, along with decreased poly (ADP-ribose) polymerase-1 (PARP1) expression. With the analysis of clinic samples, we observed that miR-520 level was negatively correlated with PARP1 level in RSA villus. In addition, overexpression of PARP1 restored the miR-520-induced trophoblast cell apoptosis in vitro. The status of chromosome in trophoblast implied that miR-520-promoted DNA-damage-induced cell apoptosis to regulate RSA progression. These results indicated that the level of miR-520 might associate with RSA by prompting trophoblast cell apoptosis via PARP1 dependent DNA-damage pathway.

  13. Single-Cell Analysis Identifies Distinct Stages of Human Endothelial-to-Hematopoietic Transition

    Directory of Open Access Journals (Sweden)

    Carolina Guibentif

    2017-04-01

    Full Text Available During development, hematopoietic cells originate from endothelium in a process known as endothelial-to-hematopoietic transition (EHT. To study human EHT, we coupled flow cytometry and single-cell transcriptional analyses of human pluripotent stem cell-derived CD34+ cells. The resulting transcriptional hierarchy showed a continuum of endothelial and hematopoietic signatures. At the interface of these two signatures, a unique group of cells displayed both an endothelial signature and high levels of key hematopoietic stem cell-associated genes. This interphase group was validated via sort and subculture as an immediate precursor to hematopoietic cells. Differential expression analyses further divided this population into subgroups, which, upon subculture, showed distinct hematopoietic lineage differentiation potentials. We therefore propose that immediate precursors to hematopoietic cells already have their hematopoietic lineage restrictions defined prior to complete downregulation of the endothelial signature. These findings increase our understanding of the processes of de novo hematopoietic cell generation in the human developmental context.

  14. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Fourth Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2013-01-01

    SunLine Transit Agency, which provides public transit services to the Coachella Valley area of California, has demonstrated hydrogen and fuel cell bus technologies for more than 10 years. In May 2010, SunLine began demonstrating the advanced technology (AT) fuel cell bus with a hybrid electric propulsion system, fuel cell power system, and lithium-based hybrid batteries. This report describes operations at SunLine for the AT fuel cell bus and five compressed natural gas buses. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is working with SunLine to evaluate the bus in real-world service to document the results and help determine the progress toward technology readiness. NREL has previously published three reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from February 2012 through November 2012.

  15. Rapid Fatal Outcome from Pulmonary Arteries Compression in Transitional Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Ioannis A. Voutsadakis

    2009-01-01

    Full Text Available Transitional cell carcinoma of the urinary bladder is a malignancy that metastasizes frequently to lymph nodes including the mediastinal lymph nodes. This occurrence may produce symptoms due to compression of adjacent structures such as the superior vena cava syndrome or dysphagia from esophageal compression. We report the case of a 59-year-old man with metastatic transitional cell carcinoma for whom mediastinal lymphadenopathy led to pulmonary artery compression and a rapidly fatal outcome. This rare occurrence has to be distinguished from pulmonary embolism, a much more frequent event in cancer patients, in order that proper and prompt treatment be initiated.

  16. Cell-State Transitions Regulated by SLUG Are Critical for Tissue Regeneration and Tumor Initiation

    Directory of Open Access Journals (Sweden)

    Sarah Phillips

    2014-05-01

    Full Text Available Perturbations in stem cell activity and differentiation can lead to developmental defects and cancer. We use an approach involving a quantitative model of cell-state transitions in vitro to gain insights into how SLUG/SNAI2, a key developmental transcription factor, modulates mammary epithelial stem cell activity and differentiation in vivo. In the absence of SLUG, stem cells fail to transition into basal progenitor cells, while existing basal progenitor cells undergo luminal differentiation; together, these changes result in abnormal mammary architecture and defects in tissue function. Furthermore, we show that in the absence of SLUG, mammary stem cell activity necessary for tissue regeneration and cancer initiation is lost. Mechanistically, SLUG regulates differentiation and cellular plasticity by recruiting the chromatin modifier lysine-specific demethylase 1 (LSD1 to promoters of lineage-specific genes to repress transcription. Together, these results demonstrate that SLUG plays a dual role in repressing luminal epithelial differentiation while unlocking stem cell transitions necessary for tumorigenesis.

  17. 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

  18. A spontaneously immortalized Schwann cell line from aldose reductase-deficient mice as a useful tool for studying polyol pathway and aldehyde metabolism.

    Science.gov (United States)

    Niimi, Naoko; Yako, Hideji; Takaku, Shizuka; Kato, Hiroshi; Matsumoto, Takafumi; Nishito, Yasumasa; Watabe, Kazuhiko; Ogasawara, Saori; Mizukami, Hiroki; Yagihashi, Soroku; Chung, Sookja K; Sango, Kazunori

    2018-03-01

    The increased glucose flux into the polyol pathway via aldose reductase (AR) is recognized as a major contributing factor for the pathogenesis of diabetic neuropathy, whereas little is known about the functional significance of AR in the peripheral nervous system. Spontaneously immortalized Schwann cell lines established from long-term cultures of AR-deficient and normal C57BL/6 mouse dorsal root ganglia and peripheral nerves can be useful tools for studying the physiological and pathological roles of AR. These cell lines, designated as immortalized knockout AR Schwann cells 1 (IKARS1) and 1970C3, respectively, demonstrated distinctive Schwann cell phenotypes, such as spindle-shaped morphology and immunoreactivity to S100, p75 neurotrophin receptor, and vimentin, and extracellular release of neurotrophic factors. Conditioned media obtained from these cells promoted neuronal survival and neurite outgrowth of cultured adult mouse dorsal root ganglia neurons. Microarray and real-time RT-PCR analyses revealed significantly down-regulated mRNA expression of polyol pathway-related enzymes, sorbitol dehydrogenase and ketohexokinase, in IKARS1 cells compared with those in 1970C3 cells. In contrast, significantly up-regulated mRNA expression of aldo-keto reductases (AKR1B7 and AKR1B8) and aldehyde dehydrogenases (ALDH1L2, ALDH5A1, and ALDH7A1) was detected in IKARS1 cells compared with 1970C3 cells. Exposure to reactive aldehydes (3-deoxyglucosone, methylglyoxal, and 4-hydroxynonenal) significantly up-regulated the mRNA expression of AKR1B7 and AKR1B8 in IKARS1 cells, but not in 1970C3 cells. Because no significant differences in viability between these two cell lines after exposure to these aldehydes were observed, it can be assumed that the aldehyde detoxification is taken over by AKR1B7 and AKR1B8 in the absence of AR. © 2017 International Society for Neurochemistry.

  19. Expression of progesterone receptor membrane component-2 within the immature rat ovary and its role in regulating mitosis and apoptosis of spontaneously immortalized granulosa cells.

    Science.gov (United States)

    Griffin, Daniel; Liu, Xiufang; Pru, Cindy; Pru, James K; Peluso, John J

    2014-08-01

    Progesterone receptor membrane component 2 (Pgrmc2) mRNA was detected in the immature rat ovary. By 48 h after eCG, Pgrmc2 mRNA levels decreased by 40% and were maintained at 48 h post-hCG. Immunohistochemical studies detected PGRMC2 in oocytes and ovarian surface epithelial, interstitial, thecal, granulosa, and luteal cells. PGRMC2 was also present in spontaneously immortalized granulosa cells, localizing to the cytoplasm of interphase cells and apparently to the mitotic spindle of cells in metaphase. Interestingly, PGRMC2 levels appeared to decrease during the G1 stage of the cell cycle. Moreover, overexpression of PGRMC2 suppressed entry into the cell cycle, possibly by binding the p58 form of cyclin dependent kinase 11b. Conversely, Pgrmc2 small interfering RNA (siRNA) treatment increased the percentage of cells in G1 and M stage but did not increase the number of cells, which was likely due to an increase in apoptosis. Depleting PGRMC2 did not inhibit cellular (3)H-progesterone binding, but attenuated the ability of progesterone to suppress mitosis and apoptosis. Taken together these studies suggest that PGRMC2 affects granulosa cell mitosis by acting at two specific stages of the cell cycle. First, PGRMC2 regulates the progression from the G0 into the G1 stage of the cell cycle. Second, PGRMC2 appears to localize to the mitotic spindle, where it likely promotes the final stages of mitosis. Finally, siRNA knockdown studies indicate that PGRMC2 is required for progesterone to slow the rate of granulosa cell mitosis and apoptosis. These findings support a role for PGRMC2 in ovarian follicle development. © 2014 by the Society for the Study of Reproduction, Inc.

  20. Loss of lysosomal membrane protein NCU-G1 in mice results in spontaneous liver fibrosis with accumulation of lipofuscin and iron in Kupffer cells

    Directory of Open Access Journals (Sweden)

    Xiang Y. Kong

    2014-03-01

    Full Text Available Human kidney predominant protein, NCU-G1, is a highly conserved protein with an unknown biological function. Initially described as a nuclear protein, it was later shown to be a bona fide lysosomal integral membrane protein. To gain insight into the physiological function of NCU-G1, mice with no detectable expression of this gene were created using a gene-trap strategy, and Ncu-g1gt/gt mice were successfully characterized. Lysosomal disorders are mainly caused by lack of or malfunctioning of proteins in the endosomal-lysosomal pathway. The clinical symptoms vary, but often include liver dysfunction. Persistent liver damage activates fibrogenesis and, if unremedied, eventually leads to liver fibrosis/cirrhosis and death. We demonstrate that the disruption of Ncu-g1 results in spontaneous liver fibrosis in mice as the predominant phenotype. Evidence for an increased rate of hepatic cell death, oxidative stress and active fibrogenesis were detected in Ncu-g1gt/gt liver. In addition to collagen deposition, microscopic examination of liver sections revealed accumulation of autofluorescent lipofuscin and iron in Ncu-g1gt/gt Kupffer cells. Because only a few transgenic mouse models have been identified with chronic liver injury and spontaneous liver fibrosis development, we propose that the Ncu-g1gt/gt mouse could be a valuable new tool in the development of novel treatments for the attenuation of fibrosis due to chronic liver damage.

  1. Mesenchymal Stem Cells Derived from Human Exocrine Pancreas Spontaneously Express Pancreas Progenitor-Cell Markers in a Cell-Passage-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Song Lee

    2016-01-01

    Full Text Available Mesenchymal stem cells (MSCs derived from bone marrow, adipose tissue, and most connective tissues have been recognized as promising sources for cell-based therapies. MSCs have also been detected in human pancreatic tissue, including endocrine and exocrine cells. These adult human pancreas-derived MSCs have generated a great deal of interest owing to their potential use in the differentiation of insulin-producing cells for diabetes treatment. In the present study, we isolated MSCs from the adult human exocrine pancreas to determine whether isolated MSCs have the potential to differentiate into pancreatic endocrine cells and, therefore, whether they can be used in stem cell-based therapies. Pancreatic tissue was digested by collagenase and an enriched exocrine-cell fraction was obtained by density-gradient separation. Crude exocrine cells were methodically cultured in suspension and then in adherent culture. We expanded the human pancreatic exocrine-derived MSCs (hpMSCs by cell passaging in culture and confirmed by flow cytometry that >90% expressed human classic surface markers of MSCs. Interestingly, these cells expressed pancreatic transcription factors, such as Pdx1, Ngn3, and MafA, similar to pancreatic progenitor cells. These results indicated that hpMSCs can be used for the differentiation of pancreatic endocrine cells and may be used in type 1 diabetes treatment.

  2. Spontaneous baryogenesis in warm inflation

    OpenAIRE

    Brandenberger, Robert H.; Yamaguchi, Masahide

    2003-01-01

    We discuss spontaneous baryogenesis in the warm inflation scenario. In contrast with standard inflation models, radiation always exists in the warm inflation scenario, and the inflaton must be directly coupled to it. Also, the transition to the post-inflationary radiation dominated phase is smooth and the entropy is not significantly increased at the end of the period of inflation. In addition, after the period of warm inflation ends, the inflaton does not oscillate coherently but slowly roll...

  3. Emerging targets in pancreatic cancer: epithelial–mesenchymal transition and cancer stem cells

    Directory of Open Access Journals (Sweden)

    Castellanos JA

    2013-09-01

    Full Text Available Jason A Castellanos,1 Nipun B Merchant,1–3 Nagaraj S Nagathihalli1–31Department of Surgery, 2Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, TN, USA; 3Vanderbilt-Ingram Comprehensive Cancer Center, Nashville, TN, USAAbstract: Pancreatic ductal adenocarcinoma is one of the most aggressive solid malignancies and is characterized by poor response to current therapy and a dismal survival rate. Recent insights regarding the role of cancer stem cells (CSCs and epithelial–mesenchymal transition (EMT in tumorigenesis have brought further understanding to the field and have highlighted new therapeutic targets. CSCs are a distinct subset of cancer cells, with the ability to differentiate into other cell types and self-renew in order to fuel the maintenance of tumor amplification. Transition of a cancer cell from an EMT leads to increased migratory and invasive properties, and thus facilitates initiation of metastasis. EMT is regulated by a complex network of factors that includes cytokines, growth factors, aberrant signaling pathways, transcription factors, and the tumor microenvironment. There is emerging evidence that the EMT process may give rise to CSCs, or at least cells with stem cell-like properties. We review the key pathways involved in both of these processes, the biomarkers used to identify CSCs, and new therapeutic approaches targeting CSCs and EMT in pancreatic ductal adenocarcinoma.Keywords: epithelial-mesenchymal transition, cancer stem cells, tumor microenvironment, pancreatic ductal adenocarcinoma

  4. Mesenchymal-epithelial transition of pancreatic cancer cells at perineural invasion sites is induced by Schwann cells.

    Science.gov (United States)

    Fujii-Nishimura, Yoko; Yamazaki, Ken; Masugi, Yohei; Douguchi, Junya; Kurebayashi, Yutaka; Kubota, Naoto; Ojima, Hidenori; Kitago, Minoru; Shinoda, Masahiro; Hashiguchi, Akinori; Sakamoto, Michiie

    2018-02-19

    Epithelial-mesenchymal transition (EMT) promotes invasion and metastasis of pancreatic ductal adenocarcinoma (PDAC). However, the importance of its reverse process, mesenchymal-epithelial transition (MET), for PDAC remains unclear. We aimed to characterize the histological finding "focal differentiation" in PDAC at perineural invasion sites in the context of MET and to investigate the role of Schwann cells in inducing tumor MET. Tumor differentiation and immunohistochemical expressions of E-cadherin, SMAD3, and vimentin at perineural invasion sites were examined in 168 PDAC tissues. Four PDAC cell lines were co-cultured with Schwann cells to investigate cell morphology, motility, or EMT-related markers using immunocytochemistry and quantitative PCR. Of 168 tumors, 124 (74%) showed focal differentiation with enhanced E-cadherin membrane expression (P grade 1/2 tumor, tumors with focal differentiation showed worse survival compared to those without focal differentiation (P = 0.019). PDAC cells co-cultured with Schwann cells demonstrated a sheet-like appearance, increased E-cadherin expression, decreased expressions of SMAD3 and vimentin, and reduced cell motility. In conclusion, MET-like change is induced by Schwann cells, suggesting that Schwann cells contribute to PDAC colonization in pancreatic nerves through activating the MET machinery inside tumor cells in the pancreatic tumor microenvironment. © 2018 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.

  5. Sheep, wolf, or werewolf: cancer stem cells and the epithelial-to-mesenchymal transition.

    Science.gov (United States)

    Chang, Jeffrey T; Mani, Sendurai A

    2013-11-28

    Multiple cancers contain subpopulations that exhibit characteristics of cancer stem cells (CSCs), the ability to self-renew and seed heterogeneous tumors. Recent evidence suggests two potentially overlapping models for these phenotypes: one where stem cells arise from multipotent progenitor cells, and another where they are created via an epithelial to mesenchymal transition. Unraveling this issue is critical, as it underlies phenomena such as metastasis and therapeutic resistance. Therefore, there is intense interest in understanding these two types of CSSs, how they differ from differentiated cancer cells, the mechanisms that drive their phenotypes, and how that knowledge can be incorporated into therapeutics. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  6. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2010

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.; Gigakis, C.

    2010-11-01

    This status report, fourth in a series of annual status reports from the U.S. Department of Energy's National Renewable Energy Laboratory, summarizes progress and accomplishments from demonstrations of fuel cell transit buses in the United States. This year's assessment report provides the results from the fifth year of operation of five Van Hool, ISE, and UTC Power fuel cell buses operating at AC Transit, SunLine, and CTTRANSIT. The achievements and challenges of this bus design, implementation, and operating are presented, with a focus on the next steps for implementing larger numbers and new and different designs of fuel cell buses. The major positive result from nearly five years of operation is the dramatic increase in reliability experienced for the fuel cell power system.

  7. Considerations for the transition from fuel cell R ampersand D to manufacturing

    International Nuclear Information System (INIS)

    Cobb, M.A.

    1992-01-01

    There are a growing number of contractors within the present fuel cell community who have the potential of becoming high volume manufacturers of fuel cell power plants or components. Many are transitioning from basic research operations to manufacturing for the first time. Moving a product from the R ampersand D stage to a viable commercial product depends upon many factors. Some companies are more successful at it than others. We believe there is an underlying transition process from invention to market that is much the same for large, well established firms, as it is for start-ups. How well the process is understood and executed often determines the winners and losers in product commercialization. This paper presents a viewpoint on considerations for transitioning a new technology into commercial production and discusses some affects on organizational development

  8. Pyrolysed 3D-Carbon Scaffolds Induce Spontaneous Differentiation of Human Neural Stem Cells and Facilitate Real-Time Dopamine Detection

    DEFF Research Database (Denmark)

    Amato, Letizia; Heiskanen, Arto; Caviglia, Claudia

    2014-01-01

    -dimensional (2D) and 3D environment. Due to conductive properties and 3D environment, the p3D-carbon serves as a neurotransmitter trap, enabling electrochemical detection of a signifi cantly larger dopamine fraction released by the hNSC derived neurons than on conventional 2D electrodes. This is the first study......Structurally patterned pyrolysed three-dimensional carbon scaffolds (p3Dcarbon) are fabricated and applied for differentiation of human neural stem cells (hNSCs) developed for cell replacement therapy and sensing of released dopamine. In the absence of differentiation factors (DF) the pyrolysed...... carbon material induces spontaneous hNSC differentiation into mature dopamine-producing neurons and the 3D-topography promotes neurite elongation. In the presence and absence of DF, ≈73–82% of the hNSCs obtain dopaminergic properties on pyrolysed carbon, a to-date unseen efficiency in both two...

  9. Angiotensin-converting enzyme inhibitor increases angiotensin type 1A receptor gene expression in aortic smooth muscle cells of spontaneously hypertensive rats.

    Science.gov (United States)

    Negoro, N; Kanayama, Y; Iwai, J; Umetani, N; Nishimura, M; Konishi, Y; Okamura, M; Inoue, T; Takeda, T

    1994-04-12

    To examine the regulation of angiotensin receptors in vascular smooth muscle cells, we studied the effects of antihypertensive drugs on angiotensin type 1A (AT1A) receptor gene expression in aortic smooth muscle cells (ASMCs) from spontaneously hypertensive rats (SHRs) using both ribonuclease protection assay and reverse-transcription polymerase chain reaction. An increase in AT1A receptor gene expression in ASMCs of SHRs was induced by treatment with an angiotensin converting enzyme inhibitor (enalapril) for 2 weeks and 4 weeks, but not by other types of antihypertensive drugs such as alpha-blocker (doxazosin), alpha, beta-blocker (arotinolol), Ca antagonist (nicardipine) or vascular smooth muscle relaxant (hydralazine). Since all antihypertensive drugs lowered the blood pressure of the rats almost equally, our results suggest that AT1A receptor gene expression in ASMCs of SHRs may be regulated by the vascular renin-angiotensin system.

  10. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chander, K.; Gikakis, C.

    2012-11-01

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results over the last year. There are 25 active FCEBs in demonstrations this year at eight locations.

  11. Transitional cell carcinoma of the bladder in childhood: radiological findings and differential diagnosis

    International Nuclear Information System (INIS)

    Casado, L.; Mansilla, F.; Mansilla, M.D.; Marin, A.

    1998-01-01

    We present a case of transitional cell carcinoma of the bladder in an 11-year-old boy. The rarity of these tumors during childhood is pointed out. The radiological and ultrasonographic findings are described and the differential diagnosis is discussed with respect to other bladder tumors occurring in childhood. (Author) 11 refs

  12. The “Funny” Current (If Inhibition by Ivabradine at Membrane Potentials Encompassing Spontaneous Depolarization in Pacemaker Cells

    Directory of Open Access Journals (Sweden)

    Yael Yaniv

    2012-07-01

    Full Text Available Recent clinical trials have shown that ivabradine (IVA, a drug that inhibits the funny current (If in isolated sinoatrial nodal cells (SANC, decreases heart rate and reduces morbidity and mortality in patients with cardiovascular diseases. While IVA inhibits If, this effect has been reported at essentially unphysiological voltages, i.e., those more negative than the spontaneous diastolic depolarization (DD between action potentials (APs. We tested the relative potency of IVA to block If over a wide range of membrane potentials, including those that encompass DD governing to the SANC spontaneous firing rate. A clinically relevant IVA concentration of 3 μM to single, isolated rabbit SANC slowed the spontaneous AP firing rate by 15%. During voltage clamp the maximal If was 18 ± 3 pA/pF (at −120 mV and the maximal If reduction by IVA was 60 ± 8% observed at −92 ± 4 mV. At the maximal diastolic depolarization (~−60 mV If amplitude was only −2.9 ± 0.4 pA/pF, and was reduced by only 41 ± 6% by IVA. Thus, If amplitude and its inhibition by IVA at physiologically relevant membrane potentials are substantially less than that at unphysiological (hyperpolarized membrane potentials. This novel finding more accurately describes how IVA affects SANC function and is of direct relevance to numerical modeling of SANC automaticity.

  13. Notch signaling: targeting cancer stem cells and epithelial-to-mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Espinoza I

    2013-09-01

    Full Text Available Ingrid Espinoza,1,2 Radhika Pochampally,1,2 Fei Xing,1 Kounosuke Watabe,1,3 Lucio Miele1,4 1Cancer Institute, 2Department of Biochemistry, 3Department of Microbiology, 4Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, USA Abstract: Notch signaling is an evolutionarily conserved pathway involved in cell fate control during development, stem cell self-renewal, and postnatal tissue differentiation. Roles for Notch in carcinogenesis, the biology of cancer stem cells, tumor angiogenesis, and epithelial-to-mesenchymal transition (EMT have been reported. This review describes the role of Notch in the “stemness” program in cancer cells and in metastases, together with a brief update on the Notch inhibitors currently under investigation in oncology. These agents may be useful in targeting cancer stem cells and to reverse the EMT process. Keywords: Notch signaling, EMT, cancer stem cells, mesenchymal stem cells, metastases, Notch inhibitors

  14. Vagal neural crest cell migratory behavior: A transition between the cranial and trunk crest

    Science.gov (United States)

    Kuo, Bryan R.; Erickson, Carol A.

    2011-01-01

    Migration and differentiation of cranial neural crest cells are largely controlled by environmental cues, whereas pathfinding at the trunk level is dictated by cell-autonomous molecular changes owing to early specification of the premigratory crest. Here, we investigated the migration and patterning of vagal neural crest cells. We show that: 1) vagal neural crest cells exhibit some developmental bias and 2) they take separate pathways to the heart and to the gut. Together these observations suggest that prior specification dictates initial pathway choice. However, when we challenged the vagal neural crest cells with different migratory environments, we observed that the behavior of the anterior vagal neural crest cells (somite-level 1-3) exhibit considerable migratory plasticity whereas the posterior vagal neural crest cells (somite-level 5-7) are more restricted in their behavior. We conclude that the vagal neural crest is a transitional population that has evolved between the head and the trunk. PMID:22016183

  15. Preprocessing with Photoshop Software on Microscopic Images of A549 Cells in Epithelial-Mesenchymal Transition.

    Science.gov (United States)

    Ren, Zhou-Xin; Yu, Hai-Bin; Shen, Jun-Ling; Li, Ya; Li, Jian-Sheng

    2015-06-01

    To establish a preprocessing method for cell morphometry in microscopic images of A549 cells in epithelial-mesenchymal transition (EMT). Adobe Photoshop CS2 (Adobe Systems, Inc.) was used for preprocessing the images. First, all images were processed for size uniformity and high distinguishability between the cell and background area. Then, a blank image with the same size and grids was established and cross points of the grids were added into a distinct color. The blank image was merged into a processed image. In the merged images, the cells with 1 or more cross points were chosen, and then the cell areas were enclosed and were replaced in a distinct color. Except for chosen cellular areas, all areas were changed into a unique hue. Three observers quantified roundness of cells in images with the image preprocess (IPP) or without the method (Controls), respectively. Furthermore, 1 observer measured the roundness 3 times with the 2 methods, respectively. The results between IPPs and Controls were compared for repeatability and reproducibility. As compared with the Control method, among 3 observers, use of the IPP method resulted in a higher number and a higher percentage of same-chosen cells in an image. The relative average deviation values of roundness, either for 3 observers or 1 observer, were significantly higher in Controls than in IPPs (p Photoshop, a chosen cell from an image was more objective, regular, and accurate, creating an increase of reproducibility and repeatability on morphometry of A549 cells in epithelial to mesenchymal transition.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-06-26

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

  17. Dimethyl sulfoxide inhibits spontaneous diabetes and autoimmune recurrence in non-obese diabetic mice by inducing differentiation of regulatory T cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Gu-Jiun [Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan, ROC (China); Sytwu, Huey-Kang [Department of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan, ROC (China); Yu, Jyh-Cherng [Department of General Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC (China); Chen, Yuan-Wu [School of Dentistry, National Defense Medical Center, Taipei, Taiwan, ROC (China); Department of Oral and Maxillofacial Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC (China); Kuo, Yu-Liang [Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan, ROC (China); School of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan, ROC (China); Yu, Chiao-Chi [Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan, ROC (China); Department of General Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC (China); Chang, Hao-Ming; Chan, De-Chuan [Department of General Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC (China); Huang, Shing-Hwa, E-mail: h610129@gmail.com [Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan, ROC (China); Department of General Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC (China)

    2015-01-15

    Type 1 diabetes mellitus (T1D) is caused by the destruction of insulin-producing β cells in pancreatic islets by autoimmune T cells. Islet transplantation has been established as an effective therapeutic strategy for T1D. However, the survival of islet grafts can be disrupted by recurrent autoimmunity. Dimethyl sulfoxide (DMSO) is a solvent for organic and inorganic substances and an organ-conserving agent used in solid organ transplantations. DMSO also exerts anti-inflammatory, reactive oxygen species scavenger and immunomodulatory effects and therefore exhibits therapeutic potential for the treatment of several human inflammatory diseases. In this study, we investigated the therapeutic potential of DMSO in the inhibition of autoimmunity. We treated an animal model of islet transplantation (NOD mice) with DMSO. The survival of the syngeneic islet grafts was significantly prolonged. The population numbers of CD8, DC and Th1 cells were decreased, and regulatory T (Treg) cell numbers were increased in recipients. The expression levels of IFN-γ and proliferation of T cells were also reduced following DMSO treatment. Furthermore, the differentiation of Treg cells from naive CD4 T cells was significantly increased in the in vitro study. Our results demonstrate for the first time that in vivo DMSO treatment suppresses spontaneous diabetes and autoimmune recurrence in NOD mice by inhibiting the Th1 immune response and inducing the differentiation of Treg cells. - Highlights: • We report a therapeutic potential of DMSO in autoimmune diabetes. • DMSO exhibits an immune modulatory effect. • DMSO treatment increases regulatory T cell differentiation. • The increase in STAT5 signaling pathway explains the effect of DMSO in Tregs.

  18. Clock frequency estimation under spontaneous emission

    Science.gov (United States)

    Qin, Xi-Zhou; Huang, Jia-Hao; Zhong, Hong-Hua; Lee, Chaohong

    2018-02-01

    We investigate the quantum dynamics of a driven two-level system under spontaneous emission and its application in clock frequency estimation. By using the Lindblad equation to describe the system, we analytically obtain its exact solutions, which show three different regimes: Rabi oscillation, damped oscillation, and overdamped decay. From the analytical solutions, we explore how the spontaneous emission affects the clock frequency estimation. We find that under a moderate spontaneous emission rate, the transition frequency can still be inferred from the Rabi oscillation. Our results enable potential practical applications in frequency measurement and quantum control under decoherence.

  19. Arachidonic acid promotes epithelial-to-mesenchymal-like transition in mammary epithelial cells MCF10A.

    Science.gov (United States)

    Martinez-Orozco, Raul; Navarro-Tito, Napoleon; Soto-Guzman, Adriana; Castro-Sanchez, Luis; Perez Salazar, Eduardo

    2010-06-01

    Epidemiological studies and animal models suggest an association between high levels of dietary fat intake and an increased risk of breast cancer. Cancer progression requires the development of metastasis, which is characterized by an increase in cell motility and invasion. Epithelial-to-mesenchymal transition (EMT) is a process, by which epithelial cells are transdifferentiated to a more mesenchymal state. A similar process takes place during tumor progression, when carcinoma cells stably or transiently lose epithelial polarities and acquire a mesenchymal phenotype. Arachidonic acid (AA) is a fatty acid that mediates cellular processes, such as cell survival, angiogenesis, chemotaxis, mitogenesis, migration and apoptosis. However, the role of AA on the EMT process in human mammary epithelial cells remains to be studied. We demonstrate here that AA promotes an increase in vimentin and N-cadherin expression, MMP-9 secretion, a decrease in E-cadherin junctional levels, and the activation of FAK, Src and NF-kappaB in MCF10A cells. Furthermore, AA also promotes cell migration in an Src kinase activity-dependent fashion. In conclusion, our results demonstrate, for the first time, that AA promotes an epithelial-to-mesenchymal-like transition in MCF10A human mammary non-tumorigenic epithelial cells. 2010 Elsevier GmbH. All rights reserved.

  20. A novel retinoic acid chalcone reverses epithelial‑mesenchymal transition in prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Jian Zhong

    2015-06-01

    Full Text Available The present study was performed to investigate the effect of retinoic acid fluoro chalcone (RAFC on lipopolysaccharide (LPS induced epithelial-mesenchymal transition (EMT in PC3 and CWR22rv1 prostate cell lines. Lipo-polysaccharide (LPS was used to induce epithelial-mesenchymal transition in prostate carcinoma cell lines. The results revealed that treatment of PC3 and CWR22rv1 cells with LPS resulted in significant changes in the morphological features of the EMT. The mesenchymal marker, vimentin expression was significantly increased whereas the expression level of E‑cadherin was markedly decreased after the treatment. We also observed increased cell motility and higher level of transcription factor glioma‑associated oncogene homolog 1 (Gli1 expression on LPS treatment. Treatment of prostate cells with RAFC reversed the morphological changes induced by LPS in prostate cells. RAFC also reduced the expression of EMT markers induced by LPS and suppressed the Gli1 expression. The resultant effect of these changes was the suppression of motility and invasiveness of the prostrate cells. Thus, RAFC exhibited anti‑invasive effect on prostrate cells by inhibition of the EMT process via Hedgehog signaling pathway.

  1. Renal transitional cell carcinoma with bilateral ocular metastasis in a cat

    Directory of Open Access Journals (Sweden)

    Irit Grader

    2016-07-01

    Full Text Available Case summary A 4-year-old, spayed female, domestic shorthair cat was presented for evaluation due to a 4 day history of inappetence and lethargy. Physical examination revealed mild dehydration and blindness of the left eye. Abnormal imaging findings included a well-margined soft tissue mass with irregular central cavity located in the dorsal aspect of the caudal lung lobe. Cytological examination of the mass revealed chronic inflammation with hemorrhage. Tests for parasitic and fungal diseases were negative. Ophthalmic examination 17 days after the cat was initially presented revealed severe diffuse pathology of both retinas. Left renomegaly was noted 22 days after the initial presentation, and cytological examination of samples obtained from the right vitreous, left kidney and the pulmonary mass yielded atypical epithelial cells exhibiting malignant changes. Post-mortem examination following euthanasia revealed renal transitional cell carcinoma with metastasis to both eyes, lungs and skeletal muscle. Immunohistochemical evaluation of the neoplastic cells in the eye revealed moderate cytoplasmic reactivity for CK7. CK20 immunohistochemistry was negative. Relevance and novel information To the best of our knowledge, this is the first report of renal transitional cell carcinoma with ocular metastasis in a cat. In addition, this report describes immunohistochemistry results of transitional cell carcinoma in a cat using CK7 and CK20.

  2. TEAD transcription factors mediate the function of TAZ in cell growth and epithelial-mesenchymal transition.

    Science.gov (United States)

    Zhang, Heng; Liu, Chen-Ying; Zha, Zheng-Yu; Zhao, Bin; Yao, Jun; Zhao, Shimin; Xiong, Yue; Lei, Qun-Ying; Guan, Kun-Liang

    2009-05-15

    The TAZ transcription co-activator has been shown to promote cell proliferation and to induce epithelial-mesenchymal transition. Recently we have demonstrated that TAZ is phosphorylated and inhibited by the Hippo tumor suppressor pathway, which is altered in human cancer. The mechanism of TAZ-mediated transcription is unclear. We demonstrate here that TEAD is a key downstream transcription factor mediating the function of TAZ. Disruption of TEAD-TAZ binding or silencing of TEAD expression blocked the function of TAZ to promote cell proliferation and to induce epithelial-mesenchymal transition, demonstrating TEAD as a key downstream effector of TAZ. We also identified CTGF, a gene that regulates cell adhesion, proliferation, and migration, as a direct target of TAZ and TEAD. Our study establishes a functional partnership between TAZ and TEAD under negative regulation by the Hippo signaling pathway.

  3. Coordinated encoding between cell types in the retina: insights from the theory of phase transitions

    Science.gov (United States)

    Sharpee, Tatyana

    2015-03-01

    In this talk I will describe how the emergence of some types of neurons in the brain can be quantitatively described by the theory of transitions between different phases of matter. The two key parameters that control the separation of neurons into subclasses are the mean and standard deviation of noise levels among neurons in the population. The mean noise level plays the role of temperature in the classic theory of phase transitions, whereas the standard deviation is equivalent to pressure, in the case of liquid-gas transitions, or to magnetic field for magnetic transitions. Our results account for properties of two recently discovered types of salamander OFF retinal ganglion cells, as well as the absence of multiple types of ON cells. We further show that, across visual stimulus contrasts, retinal circuits continued to operate near the critical point whose quantitative characteristics matched those expected near a liquid-gas critical point and described by the nearest-neighbor Ising model in three dimensions. Because the retina needs to operate under changing stimulus conditions, the observed parameters of cell types corresponded to metastable states in the region between the spinodal line and the line describing maximally informative solutions. Such properties of neural circuits can maximize information transmission in a given environment while retaining the ability to quickly adapt to a new environment. NSF CAREER award 1254123 and NIH R01EY019493

  4. Cervical in-transit metastasis from a truncal basal cell carcinoma.

    Science.gov (United States)

    Khan, Muhammad Kamaal; Powell, Steven; Cox, Neil; Robson, Andrew; Murrant, Nick

    2010-07-21

    The authors describe a rare case in which a cervical metastatic basal cell carcinoma (BCC) occurred from a small, non-ulcerated primary lesion on the trunk of a female patient. The metastasis had the same immunohistochemical staining pattern as several biopsies from the primary site. It was immediately adjacent to the left neck regional nodes and we view this as an in-transit metastasis. There is often debate about the validity of BCC metastases to lymph nodes but an in-transit lesion strengthens the argument that this does rarely occur.

  5. Cervical in-transit metastasis from a truncal basal cell carcinoma

    OpenAIRE

    Khan, Muhammad Kamaal; Powell, Steven; Cox, Neil; Robson, Andrew; Murrant, Nick

    2010-01-01

    The authors describe a rare case in which a cervical metastatic basal cell carcinoma (BCC) occurred from a small, non-ulcerated primary lesion on the trunk of a female patient. The metastasis had the same immunohistochemical staining pattern as several biopsies from the primary site. It was immediately adjacent to the left neck regional nodes and we view this as an in-transit metastasis. There is often debate about the validity of BCC metastases to lymph nodes but an in-transit lesion strengt...

  6. A screen for morphological complexity identifies regulators of switch-like transitions between discrete cell shapes.

    Science.gov (United States)

    Yin, Zheng; Sadok, Amine; Sailem, Heba; McCarthy, Afshan; Xia, Xiaofeng; Li, Fuhai; Garcia, Mar Arias; Evans, Louise; Barr, Alexis R; Perrimon, Norbert; Marshall, Christopher J; Wong, Stephen T C; Bakal, Chris

    2013-07-01

    The way in which cells adopt different morphologies is not fully understood. Cell shape could be a continuous variable or restricted to a set of discrete forms. We developed quantitative methods to describe cell shape and show that Drosophila haemocytes in culture are a heterogeneous mixture of five discrete morphologies. In an RNAi screen of genes affecting the morphological complexity of heterogeneous cell populations, we found that most genes regulate the transition between discrete shapes rather than generating new morphologies. In particular, we identified a subset of genes, including the tumour suppressor PTEN, that decrease the heterogeneity of the population, leading to populations enriched in rounded or elongated forms. We show that these genes have a highly conserved function as regulators of cell shape in both mouse and human metastatic melanoma cells.

  7. NK cells are intrinsically functional in pigs with Severe Combined Immunodeficiency (SCID) caused by spontaneous mutations in the Artemis gene

    Science.gov (United States)

    We have identified Severe Combined Immunodeficiency (SCID) in a line of Yorkshire pigs at Iowa State University. These SCID pigs lack B-cells and T-cells, but possess Natural Killer (NK) cells. This SCID phenotype is caused by recessive mutations in the Artemis gene. Interestingly, two human tumor c...

  8. Spontaneous focal activation of invariant natural killer T (iNKT cells in mouse liver and kidney

    Directory of Open Access Journals (Sweden)

    Zeng Jia

    2010-11-01

    Full Text Available Abstract Background Invariant natural killer T (iNKT cells differ from other T cells by their hyperactive effector T-cell status, in addition to the expression of NK lineage receptors and semi-invariant T-cell receptors. It is generally agreed that the immune phenotype of iNKT cells is maintained by repeated activation in peripheral tissues although no explicit evidence for such iNKT cell activity in vivo has so far been reported. Results We used an interferon (IFN-γ-inducible cytoplasmic protein, Irga6, as a histological marker for local IFN-γ production. Irga6 was intensely expressed in small foci of liver parenchymal cells and kidney tubular epithelium. Focal Irga6 expression was unaffected by germ-free status or loss of TLR signalling and was totally dependent on IFN-γ secreted by T cells in the centres of expression foci. These were shown to be iNKT cells by diagnostic T cell receptor usage and their activity was lost in both CD1 d and Jα-deficient mice. Conclusions This is the first report that supplies direct evidence for explicit activation events of NKT cells in vivo and raises issues about the triggering mechanism and consequences for immune functions in liver and kidney.

  9. Spontaneous waves in muscle fibres

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Stefan; Kruse, Karsten [Department of Theoretical Physics, Saarland University, 66041 Saarbruecken (Germany); Max Planck Institute for the Physics of Complex Systems, Noethnitzer Street 38, 01187 Dresden (Germany)

    2007-11-15

    Mechanical oscillations are important for many cellular processes, e.g. the beating of cilia and flagella or the sensation of sound by hair cells. These dynamic states originate from spontaneous oscillations of molecular motors. A particularly clear example of such oscillations has been observed in muscle fibers under non-physiological conditions. In that case, motor oscillations lead to contraction waves along the fiber. By a macroscopic analysis of muscle fiber dynamics we find that the spontaneous waves involve non-hydrodynamic modes. A simple microscopic model of sarcomere dynamics highlights mechanical aspects of the motor dynamics and fits with the experimental observations.

  10. Increasing the solar cell power output by coating with transition metal-oxide nanorods

    International Nuclear Information System (INIS)

    Kuznetsov, I.A.; Greenfield, M.J.; Mehta, Y.U.; Merchan-Merchan, W.; Salkar, G.; Saveliev, A.V.

    2011-01-01

    Highlights: → Nanoparticles enhance solar cell efficiency. → Solar cell power increase by nanorod coating. → Metal-oxide nanorods are prepared in flames. → Molybdenum oxide nanorods effectively scatter light on solar cell surface. → Scattering efficiency depends on coating density. -- Abstract: Photovoltaic cells produce electric current through interactions among photons from an ambient light source and electrons in the semiconductor layer of the cell. However, much of the light incident on the panel is reflected or absorbed without inducing the photovoltaic effect. Transition metal-oxide nanoparticles, an inexpensive product of a process called flame synthesis, can cause scattering of light. Scattering can redirect photon flux, increasing the fraction of light absorbed in the thin active layer of silicon solar cells. This research aims to demonstrate that the application of transition metal-oxide nanorods to the surface of silicon solar panels can enhance the power output of the panels. Several solar panels were coated with a nanoparticle-methanol suspension, and the power outputs of the panels before and after the treatment were compared. The results demonstrate an increase in power output of up to 5% after the treatment. The presence of metal-oxide nanorods on the surface of the coated solar cells is confirmed by electron microscopy.

  11. S100A4-neutralizing antibody suppresses spontaneous tumor progression, pre-metastatic niche formation and alters T-cell polarization balance

    DEFF Research Database (Denmark)

    Grum-Schwensen, Birgitte; Klingelhöfer, Jörg; Beck, Mette

    2015-01-01

    , decreased vessel density and inhibition of metastases. CONCLUSION: The S100A4 blocking antibody (6B12) reduces tumor growth and metastasis in a model of spontaneous breast cancer. The 6B12 antibody treatment inhibits T cell accumulation at the primary and pre-metastatic tumor sites. The 6B12 antibody acts......BACKGROUND: The tumor microenvironment plays a determinative role in stimulating tumor progression and metastasis. Notably, tumor-stroma signals affect the pattern of infiltrated immune cells and the profile of tumor-released cytokines. Among the known molecules that are engaged in stimulating...... the metastatic spread of tumor cells is the S100A4 protein. S100A4 is known as an inducer of inflammatory processes and has been shown to attract T-cells to the primary tumor and to the pre-metastatic niche. The present study aims to examine the immunomodulatory role of S100A4 in vivo and in vitro and assess...

  12. Diminished Frequency of Menstrual and Peripheral Blood NKT-Like Cells in Patients With Unexplained Recurrent Spontaneous Abortion and Infertile Women.

    Science.gov (United States)

    Hosseini, Samira; Shokri, Fazel; Pour, Soheila Ansari; Khoshnoodi, Jalal; Jeddi-Tehrani, Mahmood; Zarnani, Amir-Hassan

    2018-01-01

    Systemic monitoring of immune system may not precisely outline the local immune status in the uterus. This survey is a continuation of our previous studies on potential usefulness of menstrual blood (MB) immunophenotyping as a tool for investigation of immunological disturbances in pregnancy-related disorders. Peripheral blood (PB) and MB from healthy fertile (n = 15), unexplained recurrent spontaneous abortion (URSA; n = 15), and unexplained infertile women (n = 8) were collected simultaneously in the second day of their menstrual cycle and frequency of natural killer T (NKT)-like cell subpopulations were assessed by flow cytometry. Menstrual blood of all experimental groups contained higher percentage of TCRαβ + , CD45RO + , and CD16 - NKT-like cells compared to corresponding PB. Frequency of MB NKT-like cells in unexplained infertile participants was lower than fertile and URSA groups. Compared to normal participants, patients with URSA had lower frequency of PB TCRαβ + and higher CD16 + , while in infertile woman frequencies of PB CD45RO + , CD45RO - , CD16 - , IL17 + , and MB CD45RO + NKT-like cells were lower. Although, PB and MB seemingly have the same histological nature, our results showed that MB contained different composition of NKT-like subsets with different cytokine profiles and could be viewed as one potential biological sample for evaluation of patients with infertility and URSA.

  13. Elevated PTH induces endothelial-to-chondrogenic transition in aortic endothelial cells.

    Science.gov (United States)

    Wu, Min; Zhang, Jian-Dong; Tang, Ri-Ning; Crowley, Steven D; Liu, Hong; Lv, Lin-Li; Ma, Kun-Ling; Liu, Bi-Cheng

    2017-03-01

    Previous studies have shown that increased parathyroid hormone (PTH) attributable to secondary hyperparathyroidism in chronic kidney disease accelerates the arteriosclerotic fibrosis and calcification. Although the underlying mechanisms remain largely unknown, endothelial cells (ECs) have recently been demonstrated to participate in calcification in part by providing chondrogenic cells via the endothelial-to-mesenchymal transition (EndMT). Therefore, this study aimed to investigate whether elevated PTH could induce endothelial-to-chondrogenic transition in aortic ECs and to determine the possible underlying signaling pathway. We found that treatment of ECs with PTH significantly upregulated the expression of EndMT-related markers. Accordingly, ECs treated with PTH exhibited chondrogenic potential. In vivo, lineage-tracing model-subjected mice with endothelial-specific green fluorescent protein fluorescence to chronic PTH infusion showed a marked increase in the aortic expression of chondrocyte markers, and confocal microscopy revealed the endothelial origin of cells expressing chondrocyte markers in the aorta after PTH infusion. Furthermore, this in vitro study showed that PTH enhanced the nuclear localization of β-catenin in ECs, whereas β-catenin siRNA or DKK1, an inhibitor of β-catenin nuclear translocation, attenuated the upregulation of EndMT-associated and chondrogenic markers induced by PTH. In summary, our study demonstrated that elevated PTH could induce the transition of ECs to chondrogenic cells via EndMT, possibly mediated by the nuclear translocation of β-catenin. Copyright © 2017 the American Physiological Society.

  14. Human lung epithelial cells A549 epithelial-mesenchymal transition induced by PVA/Collagen nanofiber.

    Science.gov (United States)

    Li, Xiuchun; Yan, Shanshan; Dai, Jing; Lu, Yi; Wang, Yiqun; Sun, Man; Gong, Jinkang; Yao, Yuan

    2018-02-01

    Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells lose their cell-cell contact to become mesenchymal stem cells, which is important on development and embryogenesis, wound healing, and cancer metastasis. This research aims to investigate the effect of topological cue as modulating factor on the EMT by tuning the diameter of electrospinning nanofiber. The cell-nanofiber interaction between human lung epithelial cell A549 and electrospinning nanofibers composed of polyvinyl alcohol (PVA) and type I collagen were investigated. The electrospinning of regenerated PVA/Collagen nanofibers were performed with water/acetic acid as a spinning solvent and glutaraldehyde as a chemical cross-linker. Parameterization on concentration, applied voltage and feeding rate was finalized to generate smooth nanofibers with good homogeneity. The scanning electron microscopy result demonstrated that A549 cell appropriately achieved extended morphology by the filopodia attaching to the surface of the nanofibrous mats. When the diameter changed from 90nm to 240nm, the A549 cell was correspondingly express varied EMT related genes. Gene expression analysis was conducted by qPCR using three typical markers for detecting EMT: N-cadherin (NCad), Vimentin (Vim), and Fibronectin (Fib). An increasing expression pattern was observed on cell culturing on 170nm sample with respect to cell cultured on 90nm and 240nm. This result indicated the 170nm PVA/Collagen nanofibers induce A549 cells to process epithelial-mesenchymal transition more seriously than those on 90nm or 240nm. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Stage-Specific Gene Profiling of Germinal Cells Helps Delineate the Mitosis/Meiosis Transition.

    Science.gov (United States)

    Yuan, Ting-Lu; Huang, Wei-Jie; He, Juan; Zhang, Dong; Tang, Wei-Hua

    2018-02-01

    In flowering plants, germ lines are induced from somatic meristems within reproductive organs. Within anthers, germinal cell initials first undergo several rounds of mitotic proliferation before synchronously entering meiosis. Our understanding of the progression and the molecular basis of this mitosis to meiosis transition is still limited. Taking advantage of the correlation between anther length and premeiotic germinal cell development in maize ( Zea mays ), we studied the transcriptome dynamics of germinal cells at three sequential stages, mitotic archesporial cells, enlarging pollen mother cells at the premeiosis interphase, and pollen mother cells at the early prophase of meiosis, using laser microdissection-based expression profiling. Our analysis showed that cells undergoing the mitosis-meiosis switch exhibit robust transcriptional changes. The three stages are distinguished by the expression of genes encoding transcription factor subsets, meiotic chromosome recombination proteins, and distinct E3 ubiquitin ligases, respectively. The transcription level of genes encoding protein turnover machinery was significantly higher in these three stages of germinal cells than in mature pollen, parenchyma cells, or seedlings. Our experimental results further indicate that many meiotic genes are not only transcribed, but also translated prior to meiosis. We suggest that the enlarging pollen mother cells stage represents a crucial turning point from mitosis to meiosis for developing germinal cells. © 2018 American Society of Plant Biologists. All Rights Reserved.

  16. Spontaneous Tumor Lysis Syndrome

    Directory of Open Access Journals (Sweden)

    Alicia C. Weeks MD

    2015-08-01

    Full Text Available Tumor lysis syndrome (TLS is a known complication of malignancy and its treatment. The incidence varies on malignancy type, but is most common with hematologic neoplasms during cytotoxic treatment. Spontaneous TLS is thought to be rare. This case study is of a 62-year-old female admitted with multisystem organ failure, with subsequent diagnosis of aggressive B cell lymphoma. On admission, laboratory abnormalities included renal failure, elevated uric acid (20.7 mg/dL, and 3+ amorphous urates on urinalysis. Oliguric renal failure persisted despite aggressive hydration and diuretic use, requiring initiation of hemodialysis prior to chemotherapy. Antihyperuricemic therapy and hemodialysis were used to resolve hyperuricemia. However, due to multisystem organ dysfunction syndrome with extremely poor prognosis, the patient ultimately expired in the setting of a terminal ventilator wean. Although our patient did not meet current TLS criteria, she required hemodialysis due to uric acid nephropathy, a complication of TLS. This poses the clinical question of whether adequate diagnostic criteria exist for spontaneous TLS and if the lack of currently accepted guidelines has resulted in the underestimation of its incidence. Allopurinol and rasburicase are commonly used for prevention and treatment of TLS. Although both drugs decrease uric acid levels, allopurinol mechanistically prevents formation of the substrate rasburicase acts to solubilize. These drugs were administered together in our patient, although no established guidelines recommend combined use. This raises the clinical question of whether combined therapy is truly beneficial or, conversely, detrimental to patient outcomes.

  17. Effect of Topology Structures on Synchronization Transition in Coupled Neuron Cells System

    International Nuclear Information System (INIS)

    Liang Li-Si; Zhang Ji-Qian; Xu Gui-Xia; Liu Le-Zhu; Huang Shou-Fang

    2013-01-01

    In this paper, by the help of evolutionary algorithm and using Hindmarsh—Rose (HR) neuron model, we investigate the effect of topology structures on synchronization transition between different states in coupled neuron cells system. First, we build different coupling structure with N cells, and found the effect of synchronized transition contact not only closely with the topology of the system, but also with whether there exist the ring structures in the system. In particular, both the size and the number of rings have greater effects on such transition behavior. Secondly, we introduce synchronization error to qualitative analyze the effect of the topology structure. Furthermore, by fitting the simulation results, we find that with the increment of the neurons number, there always exist the optimization structures which have the minimum number of connecting edges in the coupling systems. Above results show that the topology structures have a very crucial role on synchronization transition in coupled neuron system. Biological system may gradually acquire such efficient topology structures through the long-term evolution, thus the systems' information process may be optimized by this scheme. (interdisciplinary physics and related areas of science and technology)

  18. Apolar and polar transitions drive the conversion between amoeboid and mesenchymal shapes in melanoma cells.

    Science.gov (United States)

    Cooper, Sam; Sadok, Amine; Bousgouni, Vicky; Bakal, Chris

    2015-11-05

    Melanoma cells can adopt two functionally distinct forms, amoeboid and mesenchymal, which facilitates their ability to invade and colonize diverse environments during the metastatic process. Using quantitative imaging of single living tumor cells invading three-dimensional collagen matrices, in tandem with unsupervised computational analysis, we found that melanoma cells can switch between amoeboid and mesenchymal forms via two different routes in shape space--an apolar and polar route. We show that whereas particular Rho-family GTPases are required for the morphogenesis of amoeboid and mesenchymal forms, others are required for transitions via the apolar or polar route and not amoeboid or mesenchymal morphogenesis per se. Altering the transition rates between particular routes by depleting Rho-family GTPases can change the morphological heterogeneity of cell populations. The apolar and polar routes may have evolved in order to facilitate conversion between amoeboid and mesenchymal forms, as cells are either searching for, or attracted to, particular migratory cues, respectively. © 2015 Cooper et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  19. Naive CD8 T-Cells Initiate Spontaneous Autoimmunity to a Sequestered Model Antigen of the Central Nervous System

    Science.gov (United States)

    Na, Shin-Young; Cao, Yi; Toben, Catherine; Nitschke, Lars; Stadelmann, Christine; Gold, Ralf; Schimpl, Anneliese; Hunig, Thomas

    2008-01-01

    In multiple sclerosis, CD8 T-cells are thought play a key pathogenetic role, but mechanistic evidence from rodent models is limited. Here, we have tested the encephalitogenic potential of CD8 T-cells specific for the model antigen ovalbumin (OVA) sequestered in oligodendrocytes as a cytosolic molecule. We show that in these "ODC-OVA" mice, the…

  20. Transitional Cell Carcinoma: A Case Report with Clinical, Histological and Cytological Findings

    Science.gov (United States)

    Kaur, Anureet; Singh, Jasbir; Bansal, Rimpi; Kaur, Rupinderjeet; Bansal, Monika; Kaur, Puneet

    2013-01-01

    Papillary carcinoma of the uterine cervix with features reminiscent of Transitional Cell Carcinoma (TCC) of urothelial origin, is a poorly recognized subtype of cervical carcinoma. This tumour has a propensity for late metastasis and local recurrence, in spite of the fact that histologically it could be misinterpreted as CIN grade III with a papillary configuration or as a squamous cell papilloma. This tumour occurs mainly in post-menopausal females, it is potentially aggressive and it presents at a more advanced stage. Here, we are presenting a case of a 65-year-old female who presented with post-menopausal bleeding and pelvic pain, and underwent hysterectomy for pyometra. The cervix showed a focus of papillary transitional carcinoma. PMID:24551687

  1. [Transitional cell carcinoma of the bladder in adolescents: a diagnosis to bear in mind].

    Science.gov (United States)

    Ruiz, Eduardo; Alarcón Caba, Martín; Toselli, Luzia; Moldes, Juan; Ormaechea, María; de Badiola, Francisco; Christiansen, Silvia

    2009-02-01

    Transitional cell carcinoma of the bladder has a high incidence in adults, but it is uncommon in children and adolescents. Hematuria is the most common symptom of presentation and vesical ecography the preferred diagnostic method. The diagnosis and treatment is performed with cystoscopy and endoscopic resection. We describe two patients: an 18 years old male, who presented with a pediculated tumor on the posterior bladder wall and a 15 years old female with a 1 cm long tumor on the posterior wall too; both were removed under endoscopic control. In both patients superficial transitional cell carcinoma was the final diagnosis and are disease free 3 and 5 years later. A review of the available literature was performed to clarify if this type of tumors must be considered malignant and try to define how long and by which way these patients must be controlled.

  2. Invasive Front Grading and Epithelial-Mesenchymal Transition in Canine Oral and Cutaneous Squamous Cell Carcinomas.

    Science.gov (United States)

    Nagamine, E; Hirayama, K; Matsuda, K; Okamoto, M; Ohmachi, T; Uchida, K; Kadosawa, T; Taniyama, H

    2017-09-01

    Oral and cutaneous tissues are the most frequent origin in canine squamous cell carcinoma (SSC). In SCC, changes in adhesion molecule expression and transition from epithelial to mesenchymal phenotype are thought to be important in development of invasive behavior of neoplastic cells at the leading front of the tumor. We therefore investigated histological invasive front grading and epithelial-mesenchymal transition (EMT) in both oral SCCs and cutaneous SCCs. EMT was assessed by evaluating immunohistochemical expression of E-cadherin, β-catenin, desmoglein, vimentin, and N-cadherin. Regardless of the anatomic location, invasive front grading resulted in higher histological grades than grading of the surface. Most oral SCCs were of significantly higher histologic grade than cutaneous SCCs ( P grade of canine SCC. We suggest that combining invasive front grading with assessment of immunohistochemical expression of E-cadherin, β-catenin, and desmoglein may allow more accurate prediction of biological behavior of canine SCCs.

  3. RADIATION THERAPY OF A PRESUMPTIVE URETHRAL TRANSITIONAL CELL CARCINOMA IN AN EASTERN GRAY SQUIRREL (SCIURUS CAROLINENSIS).

    Science.gov (United States)

    Childs-Sanford, Sara E; St-Vincent, Rachel; Hiss, Anne

    2015-12-01

    An adult female Eastern gray squirrel (Sciurus carolinensis), with a previous history of primary renal transitional cell carcinoma treated by nephrectomy, was diagnosed with a metastatic urethral transitional cell carcinoma (TCC) utilizing the veterinary bladder tumor antigen test in combination with other noninvasive diagnostic tests. The squirrel was treated with piroxicam and external beam radiation therapy given in 18 treatments over 30 days to achieve a total of 54 gray. Mild to moderate side effects from the pelvic irradiation were self-limiting and easily managed. Resolution of clinical signs was achieved for approximately 6 mo until recurrence of metastasis. This report represents the first published account of both TCC and external beam radiation therapy in an Eastern gray squirrel.

  4. Enrichment of colorectal cancer stem cells through epithelial-mesenchymal transition via CDH1 knockdown.

    Science.gov (United States)

    Ye, Jun; Wu, Dang; Shen, Jinwen; Wu, Pin; Ni, Chao; Chen, Jing; Zhao, Jing; Zhang, Tao; Wang, Xiaolei; Huang, Jian

    2012-09-01

    Cancer stem cells (CSCs) are considered to be the origin of cancer relapse and metastasis. The better understanding of CSCs, including CSCs in human colorectal cancer (CRC), may facilitate prevention and treatment. This study aimed to establish a CSC enrichment model via the induction of epithelial-mesenchymal transition (EMT) in CRC cells. We established an EMT model using the SW480 CRC cell line by CDH1 knockdown using shRNA interference. CD24+CD44+ cells were enriched in the CDH1 knockdown cells. The cells exhibited mesenchymal morphology and expressed high levels of EMT-related proteins, which confirmed that these cells had undergone EMT. Our results further showed that the proliferation rate of the transfected cells was reduced, whereas their colony-forming capacity and tumorigenesis in vivo was significantly enhanced compared to the control cells. In conclusion, these cells were highly enriched CSCs (compared to normal CSCs) and may be used as a stable model for cancer research and anticancer drug screening.

  5. Single cell migration in oral squamous cell carcinoma - possible evidence of epithelial-mesenchymal transition in vivo

    DEFF Research Database (Denmark)

    Jensen, David H; Reibel, Jesper; Mackenzie, Ian C

    2015-01-01

    BACKGROUND: The invasion of cancer cells into the surrounding normal tissue is one of the defining features of cancer. While the phenomena of tumour budding, epithelial-mesenchymal transition and the presence of myofibroblasts have independently been shown to be related to a poor prognosis of oral...... carcinomas, their relationship has not been examined in detail. METHODS: Paraffin-embedded tissues from 28 patients with oral squamous cell carcinomas were stained with antibodies to cytokeratin, α-SMA, vimentin, E-cadherin, N-cadherin and Twist and evaluated for their expression in relation to invasive...

  6. Spontaneous and induced chromosomal aberrations in bone ma-row cells of mice of different strain and age

    International Nuclear Information System (INIS)

    Lil'p, J.G.; Korogodina, Yu.V.

    1981-01-01

    The sensitivity of bone marrow cell chromosomes both to an alkylating agent thiophosphamide and #betta#-irradiation in 101/H, A/He, CBA, BALB/c and C57BL/6 aging mice has been studied. Changes in the sensitivity of bone marrow cell chromosomes with age are shown to depend both on mutagenic effect type and animal's genotype. The age dependent yield of chromosomal aberrations did not change in mice of all studied strains after #betta#-irradiation under conditions of our experiments. After the thiophosphamide effect, an increased sensitivity of bone marrow cell chromosomes was observed in the old 101/H, A/He and CBA mice as compared to the young ones. The level of induced chromosomal aberrations in C57BL/6 mice did not vary with age. Cells exhibiting multiple damages to chromosomes accurred in the bone marrow following the thiophosphamide effect. An increased sensitivity of old animals of certain strains resulted mainly from a sharp numerical growth of such cells. No increase in the number of cells in intact animals of all strains related to age dependent chromosomal structural damages was observed, whereas the accumulation of aneuploid cells probably depended on the genotype

  7. Suppressive effects of Lactobacillus casei cells, a bacterial immunostimulant, on the incidence of spontaneous thymic lymphoma in AKR mice.

    Science.gov (United States)

    Watanabe, T

    1996-06-01

    The mean survival age of female AKR/J mice was significantly prolonged, the enlargement of thymus was markedly suppressed, and the proliferation of ecotropic and recombinant murine leukemia viruses (MuLV) was markedly inhibited when 8-week-old female AKR/J mice were injected intraperitoneally (i.p.) with heat-killed Lactobacillus casei cells twice weekly for 8 weeks. In contrast, such actions of heat-killed L. casei cells were not seen in 20-week-old female AKR/J mice. The leukemogenic activity of the cell-free extract of thymus from adult female AKR/J mice in newborn female AKR/J mice was drastically reduced by i.p. treatment with heat-killed L. casei cells. The difference in adjuvant effectiveness of heat-killed L. casei cells on 8- and 20-week-old animals may be dependent on the difference in the enhancing activity of the cell-mediated immune systems between the groups induced by heat-killed L. casei cells, and, as a result, on the difference in the degree of proliferation of ecotropic and recombinant MuLV in thymus, which consequently causes thymic lymphoma.

  8. Spontaneous pneumothorax in weightlifters.

    Science.gov (United States)

    Marnejon, T; Sarac, S; Cropp, A J

    1995-06-01

    Spontaneous pneumothorax is infrequently caused by strenuous exertion. To our knowledge there has only been one case of spontaneous pneumothorax associated with weightlifting reported in the medical literature. We describe three consecutive cases of spontaneous pneumothorax associated with weightlifting. We postulate that spontaneous pneumothorax in these patients may be secondary to improper breathing techniques. It is important that physicians and weight trainers be aware of the association between weight lifting and spontaneous pneumothorax and assure that proper instruction is given to athletes who work with weights.

  9. Osteogenic markers are reduced in bone-marrow mesenchymal cells and femoral bone of young spontaneously hypertensive rats.

    Science.gov (United States)

    Landim de Barros, Thamine; Brito, Victor Gustavo Balera; do Amaral, Caril Constante Ferreira; Chaves-Neto, Antonio Hernandes; Campanelli, Ana Paula; Oliveira, Sandra Helena Penha

    2016-02-01

    Spontaneously hypertensive rats (SHR) and normotensive rats (W) has significant changes in bone metabolism. The purpose of this study was to investigate whether, the genetic predisposition, is sufficient to induce changes in the osteoblast differentiation and osteogenic markers in the BMSCs or in the femoral bone. For this we use young SHR rats without hypertension, but, with genetic predisposition in compared with young W. BMSCs were cultured in a proliferation medium (MEM) or osteogenic medium. Osteogenic differentiation was analyzed by proliferation, total protein, alkaline phosphatase, mineralization, and the mRNA expression of RUNX-2, β-cathenin, osterix, bone morphogenetic protein-2(BMP-2), osteocalcin (OCN), bone sialoprotein (BSP), collagen type I (Col I), and osteopontin (OPN). Osteoblast differentiation in SHR BMSCs (SHRC) had an increased proliferation compared with W BMSCs (WC). After osteogenic induction, there was greater reduction in proliferation in SHR (SHROM) than in W, in the same condition (WOM). On day 7, although no significant difference in the ALP activity was observed between SHROM and WOM, poor mineralization and osteoblast differentiation was noted in SHROM. The Osterix and β-catenin are involved in the reduced osteoblast differentiation in SHROM. The decreased expression of osteoblast-associated proteins such as OCN, BSP, COL I and OPN revealed poor quality of extracellular matrix (ECM) in SHROM. In the femoral bone, the immunostaining of COL1, BALP, OPN and OCN in SHR was decreased compared with the W. TRAP-positive immunoreactions were observed in major extension in the SHR femur. This study is the first to compare osteoblast differentiation in vitro and femoral bone from SHR and W rats. Our results demonstrated that young SHR (4weeks old), without hypertension, but with genetic predisposition, had alterations in osteoblast differentiation of BMSCs and in the femoral bone when compared with their progenitor strain, W. Copyright

  10. Retrospective evaluation of doxorubicin-piroxicam combination for the treatment of transitional cell carcinoma in dogs.

    Science.gov (United States)

    Robat, C; Burton, J; Thamm, D; Vail, D

    2013-02-01

    To determine whether doxorubicin-piroxicam combination is safe and has activity against transitional cell carcinoma in dogs. Data was collected retrospectively from 34 dogs from two institutions over a 6-year period. Signalment, clinical presentation, treatment specifics, adverse events, response, progression-free survival and overall survival time were evaluated. Dogs received doxorubicin every 3 weeks and daily piroxicam; 17 dogs (50%) had surgery. Clinical presentations were those typically reported for transitional cell carcinoma. Mean number of doses administered was 3·5. Of the 23 dogs with measurable disease, 14 (60·5%) had stable disease, 7 (30·5%) had progressive disease and 2 (9%) a partial response. Adverse events were generally manageable, and gastrointestinal in origin; one dog died of treatment-related complications. Overall median progression-free survival and overall survival were 103 and 168 days, respectively. Cytoreductive surgery did not result in prolongation of progression-free survival, but significantly prolonged overall survival. All dogs but one died as a result of disease progression. Doxorubicin-piroxicam combination therapy is well-tolerated in dogs with transitional cell carcinoma although progression-free survival, overall survival and biological response rates appear modest. Combination with surgery appears to offer a survival advantage; however, this may reflect tumour location and volume. Prospective studies are necessary to compare activity of combination doxorubicin-piroxicam to currently applied therapies. © 2013 British Small Animal Veterinary Association.

  11. Cell transmission model of dynamic assignment for urban rail transit networks.

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    Guangming Xu

    Full Text Available For urban rail transit network, the space-time flow distribution can play an important role in evaluating and optimizing the space-time resource allocation. For obtaining the space-time flow distribution without the restriction of schedules, a dynamic assignment problem is proposed based on the concept of continuous transmission. To solve the dynamic assignment problem, the cell transmission model is built for urban rail transit networks. The priority principle, queuing process, capacity constraints and congestion effects are considered in the cell transmission mechanism. Then an efficient method is designed to solve the shortest path for an urban rail network, which decreases the computing cost for solving the cell transmission model. The instantaneous dynamic user optimal state can be reached with the method of successive average. Many evaluation indexes of passenger flow can be generated, to provide effective support for the optimization of train schedules and the capacity evaluation for urban rail transit network. Finally, the model and its potential application are demonstrated via two numerical experiments using a small-scale network and the Beijing Metro network.

  12. Cytological diagnosis of a rare case of cutaneous metastasis from transitional cell carcinoma, renal pelvis

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    Pragya Singh

    2017-12-01

    Full Text Available Transitional cell carcinoma (TCC arising from renal pelvis rarely gives rise to cutaneous metastasis. Due to the insufficient literature, the exact incidence is not known till date. Moreover, the diagnosis is confirmed on histopathological examination with the aid of immunohistochemistry wherever needed. We are presenting a case of a 70-year-old female with metastatic TCC from the renal pelvis to the abdominal skin, which was diagnosed on cytology alone along with the cell block preparation. We also highlight the important cytomorphological and immunohistochemical features noted, which need to be known to avoid any diagnostic delay.

  13. Beat-to-Beat Variation in Periodicity of Local Calcium Releases Contributes to Intrinsic Variations of Spontaneous Cycle Length in Isolated Single Sinoatrial Node Cells.

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    Oliver Monfredi

    Full Text Available Spontaneous, submembrane local Ca(2+ releases (LCRs generated by the sarcoplasmic reticulum in sinoatrial nodal cells, the cells of the primary cardiac pacemaker, activate inward Na(+/Ca(2+-exchange current to accelerate the diastolic depolarization rate, and therefore to impact on cycle length. Since LCRs are generated by Ca(2+ release channel (i.e. ryanodine receptor openings, they exhibit a degree of stochastic behavior, manifested as notable cycle-to-cycle variations in the time of their occurrence.The present study tested whether variation in LCR periodicity contributes to intrinsic (beat-to-beat cycle length variability in single sinoatrial nodal cells.We imaged single rabbit sinoatrial nodal cells using a 2D-camera to capture LCRs over the entire cell, and, in selected cells, simultaneously measured action potentials by perforated patch clamp.LCRs begin to occur on the descending part of the action potential-induced whole-cell Ca(2+ transient, at about the time of the maximum diastolic potential. Shortly after the maximum diastolic potential (mean 54±7.7 ms, n = 14, the ensemble of waxing LCR activity converts the decay of the global Ca(2+ transient into a rise, resulting in a late, whole-cell diastolic Ca(2+ elevation, accompanied by a notable acceleration in diastolic depolarization rate. On average, cells (n = 9 generate 13.2±3.7 LCRs per cycle (mean±SEM, varying in size (7.1±4.2 µm and duration (44.2±27.1 ms, with both size and duration being greater for later-occurring LCRs. While the timing of each LCR occurrence also varies, the LCR period (i.e. the time from the preceding Ca(2+ transient peak to an LCR's subsequent occurrence averaged for all LCRs in a given cycle closely predicts the time of occurrence of the next action potential, i.e. the cycle length.Intrinsic cycle length variability in single sinoatrial nodal cells is linked to beat-to-beat variations in the average period of individual LCRs each cycle.

  14. EFFECTS OF THE ANTIMUTAGENS VANILLIN AND CINNAMALDEHYDE ON SPONTANEOUS MUTATION IN E. COLI LACL STRAINS AND ON GLOBAL GENE EXPRESSION IN SALMONELLA TA104 AND HUMAN HEPG2 CELLS

    Science.gov (United States)

    Effects of the Antimutagens Vanillin and Cinnamaldehyde on Spontaneous Mutation in E. coli lacI Strains and on Global Gene Epression in Salmonella TAlO4 and Human HepG2 Cells In previous work we have shown that vanillin (VAN) and cinnamaldehyde (CIN) are dietary antimutag...

  15. Epithelial mesenchymal transition of non-small-cell lung cancer cells A549 induced by SPHK1.

    Science.gov (United States)

    Ni, Min; Shi, Xiao-Lei; Qu, Zhi-Gang; Jiang, Hong; Chen, Zi-Qian; Hu, Jun

    2015-02-01

    To explore the effect and molecular mechanism of SPHK1 in the invasion and metastasis process of non-small-cell lung cancer cells (A549). Recombinant retrovirus was used to mediate the production of A549/vector, A549/SPHK1, A549/scramble, and A549/SPHKl/RNAi that stably expressed or silenced SPHK1. The invasion and migration capacities of A549 cells overexpressing or silencing SPHK1 were determined using Transwell invasion assay and scratch wound repair experiment. The protein and mRNA expression levels of E-cadherin, fibronectin, vimentin in A549/vector, A549/SPHK1, A549/scramble, A549/SPHK1/RNAi were detected with Western blot (WB) and quantitative PCR (QPCR) methods, respectively. Transwell invasion assay and scratch wound repair experiments showed that over-expression of SPHK1 obviously enhanced the invasion and migration capacities of A549 cells. WB and QPCR detection results showed that, the expression of E-cadherin (a molecular marker of epithelial cells) and fibronectin, vimentin (molecular markers of mesenchymal cells) in A549 cells was upregulated after overexpression of SPHK1; while SPHK1 silencing significantly reduced the invasion and metastasis capacities of A549 cells, upregulated the expression of molecular marker of epithelial cells, and downregulated the expression of molecular marker of mesenchymal cells. SPHK1 promotes epithelial mesenchymal transition of non-small-cell lung cancer cells and affects the invasion and metastasis capacities of these cells. Copyright © 2015 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

  16. The ducky2J mutation in Cacna2d2 results in reduced spontaneous Purkinje cell activity and altered gene expression

    Science.gov (United States)

    Donato, Roberta; Page, Karen M.; Koch, Dietlind; Nieto-Rostro, Manuela; Foucault, Isabelle; Davies, Anthony; Wilkinson, Tonia; Rees, Michele; Edwards, Frances A.; Dolphin, Annette C.

    2006-01-01

    The mouse mutant ducky and its allele ducky2J represent a model for absence epilepsy characterized by spike-wave seizures, and cerebellar ataxia. These mice have mutations in Cacna2d2, which encodes the α2δ-2 calcium channel subunit. Of relevance to the ataxic phenotype, α2δ-2 mRNA is strongly expressed in cerebellar Purkinje cells (PCs). The Cacna2d2du2J mutation results in a two base-pair deletion in the coding region and a complete loss of α2δ-2 protein. Here we show that du2J/du2J mice have a 30% reduction in somatic calcium current, and a marked fall in the spontaneous PC firing rate at 22°C, accompanied by a decrease in firing regularity, which is not affected by blocking synaptic input to PCs. At 34°C du2J/du2J PCs show no spontaneous intrinsic activity. Du2J/du2J mice also have alterations in the cerebellar expression of several genes related to PC function. At P21 there is an elevation of tyrosine hydroxylase mRNA and a reduction in tenascin-C gene expression. Although du2J/+ mice have a marked reduction in α2δ-2 protein, they show no fall in PC somatic calcium currents or increase in cerebellar tryrosine hydroxylase gene expression. However, du2J/+ PCs do exhibit a significant reduction in firing rate, correlating with the reduction in α2δ-2. A hypothesis for future study is that effects on gene expression occur as a result of a reduction in somatic calcium currents, whereas effects on PC firing occur as a long-term result of loss of α2δ-2 and/or a reduction in calcium currents and calcium-dependent processes in regions other than the soma. PMID:17135419

  17. The ducky(2J) mutation in Cacna2d2 results in reduced spontaneous Purkinje cell activity and altered gene expression.

    Science.gov (United States)

    Donato, Roberta; Page, Karen M; Koch, Dietlind; Nieto-Rostro, Manuela; Foucault, Isabelle; Davies, Anthony; Wilkinson, Tonia; Rees, Michele; Edwards, Frances A; Dolphin, Annette C

    2006-11-29

    The mouse mutant ducky and its allele ducky(2J) represent a model for absence epilepsy characterized by spike-wave seizures and cerebellar ataxia. These mice have mutations in Cacna2d2, which encodes the alpha2delta-2 calcium channel subunit. Of relevance to the ataxic phenotype, alpha2delta-2 mRNA is strongly expressed in cerebellar Purkinje cells (PCs). The Cacna2d2(du2J) mutation results in a 2 bp deletion in the coding region and a complete loss of alpha2delta-2 protein. Here we show that du(2J)/du(2J) mice have a 30% reduction in somatic calcium current and a marked fall in the spontaneous PC firing rate at 22 degrees C, accompanied by a decrease in firing regularity, which is not affected by blocking synaptic input to PCs. At 34 degrees C, du(2J)/du(2J) PCs show no spontaneous intrinsic activity. Du(2J)/du(2J) mice also have alterations in the cerebellar expression of several genes related to PC function. At postnatal day 21, there is an elevation of tyrosine hydroxylase mRNA and a reduction in tenascin-C gene expression. Although du(2J)/+ mice have a marked reduction in alpha2delta-2 protein, they show no fall in PC somatic calcium currents or increase in cerebellar tyrosine hydroxylase gene expression. However, du(2J)/+ PCs do exhibit a significant reduction in firing rate, correlating with the reduction in alpha2delta-2. A hypothesis for future study is that effects on gene expression occur as a result of a reduction in somatic calcium currents, whereas effects on PC firing occur as a long-term result of loss of alpha2delta-2 and/or a reduction in calcium currents and calcium-dependent processes in regions other than the soma.

  18. Actin cytoskeleton regulation of epithelial mesenchymal transition in metastatic cancer cells.

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    Jay Shankar

    Full Text Available Epithelial-mesenchymal transition (EMT is associated with loss of the cell-cell adhesion molecule E-cadherin and disruption of cell-cell junctions as well as with acquisition of migratory properties including reorganization of the actin cytoskeleton and activation of the RhoA GTPase. Here we show that depolymerization of the actin cytoskeleton of various metastatic cancer cell lines with Cytochalasin D (Cyt D reduces cell size and F-actin levels and induces E-cadherin expression at both the protein and mRNA level. Induction of E-cadherin was dose dependent and paralleled loss of the mesenchymal markers N-cadherin and vimentin. E-cadherin levels increased 2 hours after addition of Cyt D in cells showing an E-cadherin mRNA response but only after 10-12 hours in HT-1080 fibrosarcoma and MDA-MB-231 cells in which E-cadherin mRNA level were only minimally affected by Cyt D. Cyt D treatment induced the nuclear-cytoplasmic translocation of EMT-associated SNAI 1 and SMAD1/2/3 transcription factors. In non-metastatic MCF-7 breast cancer cells, that express E-cadherin and represent a cancer cell model for EMT, actin depolymerization with Cyt D induced elevated E-cadherin while actin stabilization with Jasplakinolide reduced E-cadherin levels. Elevated E-cadherin levels due to Cyt D were associated with reduced activation of Rho A. Expression of dominant-negative Rho A mutant increased and dominant-active Rho A mutant decreased E-cadherin levels and also prevented Cyt D induction of E-cadherin. Reduced Rho A activation downstream of actin remodelling therefore induces E-cadherin and reverses EMT in cancer cells. Cyt D treatment inhibited migration and, at higher concentrations, induced cytotoxicity of both HT-1080 fibrosarcoma cells and normal Hs27 fibroblasts, but only induced mesenchymal-epithelial transition in HT-1080 cancer cells. Our studies suggest that actin remodelling is an upstream regulator of EMT in metastatic cancer cells.

  19. Cell Cycle Remodeling and Zygotic Gene Activation at the Midblastula Transition.

    Science.gov (United States)

    Zhang, Maomao; Skirkanich, Jennifer; Lampson, Michael A; Klein, Peter S

    2017-01-01

    Following fertilization, vertebrate embryos delay large-scale activation of the zygotic genome from several hours in fish and amphibians to several days in mammals. Externally developing embryos also undergo synchronous and extraordinarily rapid cell divisions that are accelerated by promiscuous licensing of DNA replication origins, absence of gap phases and cell cycle checkpoints, and preloading of the egg with maternal RNAs and proteins needed to drive early development. After a species-specific number of cell divisions, the cell cycle slows and becomes asynchronous, gap phases appear, checkpoint functions are acquired, and large-scale zygotic gene activation begins. These events, along with clearance of maternal RNAs and proteins, define the maternal to zygotic transition and are coordinated at a developmental milestone termed the midblastula transition (MBT). Despite the relative quiescence of the zygotic genome in vertebrate embryos, genes required for clearance of maternal RNAs and for the initial steps in mesoderm induction are robustly transcribed before MBT. The coordination and timing of the MBT depends on a mechanism that senses the ratio of nuclear to cytoplasmic content as well as mechanisms that are independent of the nuclear-cytoplasm ratio. Changes in chromatin architecture anticipate zygotic gene activation, and maternal transcription factors identified as regulators of pluripotency play critical roles in kick-starting the transition from the proliferative, pluripotent state of the early embryo to the more lineage-committed phase of development after the MBT. This chapter describes the regulation of the cell cycle and the activation of zygotic gene expression before and after the MBT in vertebrate embryos.

  20. Spontaneous Remission of Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma of the Elderly

    Directory of Open Access Journals (Sweden)

    T. Mizuno

    2013-05-01

    Full Text Available A 94-year-old female patient presented with anorexia and left axillar lymphadenopathy on admission. Her past history was angina pectoris at 83 years of age and total gastrectomy due to gastric cancer at 87 years. The family history revealed that her son had had a malignant lymphoma, the histopathological diagnosis of which was diffuse large B-cell lymphoma. A physical examination showed both cervical, axillar, and inguinal lymphadenopathy without tenderness. She had elevated lactate dehydrogenase, ferritin, and soluble interleukin-2 receptor (sIL-2R. Whole-body computed tomography confirmed the cervical, axillary, and inguinal lymphadenopathy. Gallium-68 imaging revealed positive accumulation in these superficial lymph nodes. A right inguinal lymph node biopsy showed features of Epstein-Barr virus-associated lymphoproliferative disorder. Immunohistological studies on this lymph node biopsy showed CD20-positive large cells, CD3-positive small cells, and CD30-partly-positive large cells. In situ hybridization showed Epstein-Barr virus-positive, LMP-partly-positive, and EBNA2-negative cells. She refused chemotherapy as her son had died from hematemesis during chemotherapy. She received intravenous hyperalimentation for 1 month after admission. No palpable lymph nodes were identified by physical examination or computed tomography 3 months after admission, and regression of lactate dehydrogenase, ferritin, and sIL-2R was observed. She recovered from anorexia and was discharged. She died from pneumonia 10 months later after initial symptoms of anorexia. The autopsy showed no superficial lymphadenopathy.

  1. Oxidative stress, mitochondrial permeability transition, and cell death in Cu-exposed trout hepatocytes

    International Nuclear Information System (INIS)

    Krumschnabel, Gerhard; Manzl, Claudia; Berger, Christian; Hofer, Bettina

    2005-01-01

    We have previously shown that, in trout hepatocytes, exposure to a high dose of copper (Cu) leads to disruption of Ca 2+ homeostasis and elevated formation of reactive oxygen species (ROS), with the latter ultimately causing cell death. In the present study, we aimed at identifying, using a lower Cu concentration, the role of mitochondria in this scenario, the potential involvement of the mitochondrial permeability transition (MPT), and the mode of cell death induced by the metal. Incubation with 10 μM Cu resulted in a strong stimulation of ROS formation, and after 2 h of exposure a significant increase of both apoptotic and necrotic cells was seen. Co-incubation of Cu-treated hepatocytes with the iron-chelator deferoxamine significantly inhibited ROS production and completely prevented cell death. The origin of the radicals generated was at least partly mitochondrial, as visualized by confocal laser scanning microscopy. Furthermore, ROS production was diminished by inhibition of mitochondrial respiration, but since this also aggravated the elevation of intracellular Ca 2+ induced by Cu, it did not preserve cell viability. In a sub-population of cells, Cu induced a decrease of mitochondrial membrane potential and occurrence of the MPT. Cyclosporin A, which did not inhibit ROS formation, prevented the onset of the MPT and inhibited apoptotic, but not necrotic, cell death. Cu-induced apoptosis therefore appears to be dependent on induction of the MPT, but the prominent contribution of mitochondria to ROS generation also suggests an important role of mitochondria in necrotic cell death

  2. Proteinase-activated receptor 4 stimulation-induced epithelial-mesenchymal transition in alveolar epithelial cells

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    Araki Hiromasa

    2007-04-01

    Full Text Available Abstract Background Proteinase-activated receptors (PARs; PAR1–4 that can be activated by serine proteinases such as thrombin and neutrophil catepsin G are known to contribute to the pathogenesis of various pulmonary diseases including fibrosis. Among these PARs, especially PAR4, a newly identified subtype, is highly expressed in the lung. Here, we examined whether PAR4 stimulation plays a role in the formation of fibrotic response in the lung, through alveolar epithelial-mesenchymal transition (EMT which contributes to the increase in myofibroblast population. Methods EMT was assessed by measuring the changes in each specific cell markers, E-cadherin for epithelial cell, α-smooth muscle actin (α-SMA for myofibroblast, using primary cultured mouse alveolar epithelial cells and human lung carcinoma-derived alveolar epithelial cell line (A549 cells. Results Stimulation of PAR with thrombin (1 U/ml or a synthetic PAR4 agonist peptide (AYPGKF-NH2, 100 μM for 72 h induced morphological changes from cobblestone-like structure to elongated shape in primary cultured alveolar epithelial cells and A549 cells. In immunocytochemical analyses of these cells, such PAR4 stimulation decreased E-cadherin-like immunoreactivity and increased α-SMA-like immunoreactivity, as observed with a typical EMT-inducer, tumor growth factor-β (TGF-β. Western blot analyses of PAR4-stimulated A549 cells also showed similar changes in expression of these EMT-related marker proteins. Such PAR4-mediated changes were attenuated by inhibitors of epidermal growth factor receptor (EGFR kinase and Src. PAR4-mediated morphological changes in primary cultured alveolar epithelial cells were reduced in the presence of these inhibitors. PAR4 stimulation increased tyrosine phosphorylated EGFR or tyrosine phosphorylated Src level in A549 cells, and the former response being inhibited by Src inhibitor. Conclusion PAR4 stimulation of alveolar epithelial cells induced epithelial

  3. An assessment of norepinephrine mediated hypertrophy to apoptosis transition in cardiac cells: a signal for cell death.

    Science.gov (United States)

    Jain, Aditi; Atale, Neha; Kohli, Shrey; Bhattacharya, Susinjan; Sharma, Manish; Rani, Vibha

    2015-01-05

    Heart is an organ which is under a constant work load that generates numerous stress responses. Heart failure is associated with increased plasma norepinephrine (NE) and hypertrophic cell death. Within the current study we try to understand the concentration dependent molecular switch from hypertrophy to apoptosis under stress. The effect of increasing concentration of NE on cell death was studied using MTT assay based on which further experimental conditions were decided. Trypan Blue staining and TUNEL assay were done at selected concentrations of NE. Cellular and nuclear morphology at these concentrations was studied using Haematoxylin-Eosin, DAPI and PI stains. The molecular switch between hypertrophy and cell death was studied by expression analysis of β-MyHC and TNF-α. Rhodamine and DCFH-DA staining were done to evaluate the role of mitochondria and ROS under these conditions. Role of caspases under these transitions was also evaluated. NE shows steep falls in cell viability at 50 μM and 100 μM concentrations. The cellular and nuclear morphology is altered at these concentrations along with alterations at molecular level showing a shift from hypertrophy towards cell death. Altered mitochondrial membrane potential and increase in ROS support this which leads to caspase dependent activation of cell death. We show that at 50 μM NE, there occurs a transition from cellular hypertrophy towards death. This could be beneficial to prevent hypertrophy induced cardiac cell death and evaluating cardio protective therapeutic targets in vitro. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. Triclosan potentiates epithelial-to-mesenchymal transition in anoikis-resistant human lung cancer cells.

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    Thidarat Winitthana

    Full Text Available Alteration of cancer cell toward mesenchymal phenotype has been shown to potentiate tumor aggressiveness by increasing cancer cell metastasis. Herein, we report the effect of triclosan, a widely used antibacterial agent found in many daily products, in enhancing the epithelial-to-mesenchymal transition (EMT in aggressive anoikis resistant human H460 lung cancer cells. EMT has been long known to increase abilities of the cells to increase migration, invasion, and survival in circulating system. The present study reveals that treatment of the cancer cells with triclosan at the physiologically related concentrations significantly increased the colony number of the cancer cells assessed by tumor formation assay. Also, the mesenchymal-like morphology and decrease in cell-to-cell adhesion were observed in triclosan-treated cells. Importantly, western blot analysis revealed that triclosan-treated cells exhibited decreased E-cadherin, while the levels of EMT markers, namely N-cadherin, vimentin, snail and slug were found to be significantly up-regulated. Furthermore, EMT induced by triclosan treatment was accompanied by the activation of focal adhesion kinase/ATP dependent tyrosine kinase (FAK/Akt and Ras-related C3 botulinum toxin substrate 1 (Rac1, which enhanced the ability of the cells to migrate and invade. In conclusion, we demonstrated for the first time that triclosan may potentiate cancer cells survival in detached condition and motility via the process of EMT. As mentioned capabilities are required for success in metastasis, the present study provides the novel toxicological information and encourages the awareness of triclosan use in cancer patients.

  5. Resveratrol Inhibits Cisplatin-Induced Epithelial-to-Mesenchymal Transition in Ovarian Cancer Cell Lines

    Science.gov (United States)

    Baribeau, Sébastien; Chaudhry, Parvesh; Parent, Sophie; Asselin, Éric

    2014-01-01

    Background Many patients diagnosed with ovarian cancer experience recurrence and metastasis, two aspects that will often cause their demise. Epithelial-to-mesenchymal transition (EMT) is a key process involved in cancer progression. With increasing evidence linking Cisplatin and EMT, we wanted to identify a compound able to counter EMT progression when cancer cells are treated with Cisplatin. Methodology/Principal Findings Cell death was evaluated by cytometry with Annexin V/PI staining in A2780 and A2780CP cells. Ovarian cancer cell lines were treated with Cisplatin (24 h, 10 µM) and different concentrations of Resveratrol to evaluate its effect on Cisplatin-induced EMT using Western Blot and RT-PCR analysis. Morphological studies and wound healing assay to evaluate cell motility were performed using 72 h Cisplatin treatment with A2780 and A2780CP cells. Densitometry was done on Western Blot and PCR results, and statistical significance was determined using One-Way ANOVA followed by Tukey post-hoc test. Our results show that Cisplatin induced EMT-associated morphological changes in the A2780 ovarian cancer cell line and to a lesser extent in its Cisplatin-resistant counterpart A2780CP. Resveratrol caused cell death in A2780 and A2780CP cell lines in an apoptotic-independent manner. Resveratrol inhibited Cisplatin-induced Snail expression by reducing the Erk pathway activation, reverted morphological changes induced by Cisplatin and decreased cell migration. Conclusions These results indicate that Resveratrol has interesting potential to prevent Cisplatin-induced EMT in ovarian cancer cells. By increasing cell death, it also represents an inviting approach as adjuvant therapy to be used with chemotherapy. Using Erk pathway inhibitors could also prove helpful in ovarian cancer treatment to reduce the risk of metastasis. PMID:24466305

  6. Flexoelectric instability and a spontaneous chiral-symmetry breaking in a nematic liquid crystal cell with asymmetric boundary conditions.

    Science.gov (United States)

    Palto, S P; Mottram, N J; Osipov, M A

    2007-06-01

    Using both numerical simulations and an approximate analytical theory we describe a flexoelectric-induced instability in a thin nematic liquid crystal layer with asymmetric boundary conditions subjected to an applied electric field. The dependence of the threshold value of the electric field on principal material parameters of the nematic liquid crystal and the director distribution in different regions of the cell have been studied in detail numerically. The results have been compared with a simple analytical theory that enables us to obtain explicit expressions for the threshold electric field and the period of modulation above the threshold. It has been found that in the hybrid aligned nematic cell with homeotropic anchoring on one surface and planar homogeneous anchoring on the other surface, a periodic flexoelectric-induced domain structure appears, above a critical threshold, with a chiral director distribution. The director rotates about the alignment axis when moving along a perpendicular direction in the plane of the cell. The absolute value of the threshold field has been found to depend on the direction of the field due to the initial symmetry of the hybrid aligned cell and the presence of flexoelectricity.

  7. Histone deacetylase inhibitors induce epithelial-to-mesenchymal transition in prostate cancer cells.

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    Dejuan Kong

    Full Text Available Clinical experience of histone deacetylase inhibitors (HDACIs in patients with solid tumors has been disappointing; however, the molecular mechanism of treatment failure is not known. Therefore, we sought to investigate the molecular mechanism of treatment failure of HDACIs in the present study. We found that HDACIs Trichostatin A (TSA and Suberoylanilide hydroxamic acid (SAHA could induce epithelial-to-mesenchymal transition (EMT phenotype in prostate cancer (PCa cells, which was associated with changes in cellular morphology consistent with increased expression of transcription factors ZEB1, ZEB2 and Slug, and mesenchymal markers such as vimentin, N-cadherin and Fibronectin. CHIP assay showed acetylation of histone 3 on proximal promoters of selected genes, which was in part responsible for increased expression of EMT markers. Moreover, TSA treatment led to further increase in the expression of Sox2 and Nanog in PCa cells with EMT phenotype, which was associated with cancer stem-like cell (CSLC characteristics consistent with increased cell motility. Our results suggest that HDACIs alone would lead to tumor aggressiveness, and thus strategies for reverting EMT-phenotype to mesenchymal-to-epithelial transition (MET phenotype or the reversal of CSLC characteristics prior to the use of HDACIs would be beneficial to realize the value of HDACIs for the treatment of solid tumors especially PCa.

  8. [Relationship between epithelial-mesenchymal transition and basal cell-like phenotype in breast cancer].

    Science.gov (United States)

    Wu, Wan-xin; Zhang, Yan-ping; Wen, Xiao-wei; Lu, Ning; Tang, Zheng-ying; Zhang, Yi; Wang, Zhen; Wang, Wei; Yang, Hong-jie

    2009-08-01

    To evaluate the relationship between epithelial-mesenchymal transition and basal cell-like phenotype breast cancer (BLBC). Three hundred and eighty two cases of breast cancers including basal cell-like, luminal A, luminal B and Her-2 subtypes were collected from 458 cases of invasive breast cancers based on their immunophenotypes. They were then stained immunohistochemically with FOXC-2, vimentin, Syndecan-1 and E-cadherin. The relationship of these markers with the basal cell-like phenotype of breast cancer was studied. Of the 41 BLBC cases, FOXC-2, vimentin and Syndecan-1 were positive in 14 cases (34.1%), 18 cases (43.9%) and 36 cases (87.7%) respectively; E-cadherin expression was reduced in 26 cases (63.4%). The positive rates of FOXC-2 and vimentin were higher in BLBC than in other subtypes of breast cancer (P nodes in FOXC-2 and vimentin positive BLBC cases were 71.4% and 66.7% respectively, and both were higher than those of FOXC-2 and vimentin negative BLBC cases (P = 0.002 and P = 0.001). Epithelial-mesenchymal transition is probably related to the basal cell-like phenotype of breast cancers, and this may be one of the reasons accounting for the different biological behavior of BLBC from other subtypes of breast cancer.

  9. Selective arterial embolization for control of haematuria secondary to advanced or recurrent transitional cell carcinoma of the bladder.

    LENUS (Irish Health Repository)

    Halpenny, D

    2014-05-02

    Haematuria is a common symptom in patients with advanced transitional cell carcinoma of the bladder. We report our experience of selective pelvic embolization using gelfoam as an embolic agent to treat intractable haematuria in these patients.

  10. Proteotypic classification of spontaneous and transgenic mammary neoplasms

    International Nuclear Information System (INIS)

    Mikaelian, Igor; Blades, Natalie; Churchill, Gary A; Fancher, Karen; Knowles, Barbara B; Eppig, Janan T; Sundberg, John P

    2004-01-01

    Mammary tumors in mice are categorized by using morphologic and architectural criteria. Immunolabeling for terminal differentiation markers was compared among a variety of mouse mammary neoplasms because expression of terminal differentiation markers, and especially of keratins, provides important information on the origin of neoplastic cells and their degree of differentiation. Expression patterns for terminal differentiation markers were used to characterize tumor types and to study tumor progression in transgenic mouse models of mammary neoplasia (mice overexpressing Neu (Erbb2), Hras, Myc, Notch4, SV40-TAg, Tgfa, and Wnt1), in spontaneous mammary carcinomas, and in mammary neoplasms associated with infection by the mouse mammary tumor virus (MMTV). On the basis of the expression of terminal differentiation markers, three types of neoplasm were identified: first, simple carcinomas composed exclusively of cells with a luminal phenotype are characteristic of neoplasms arising in mice transgenic for Neu, Hras, Myc, Notch4, and SV40-TAg; second, 'complex carcinomas' displaying luminal and myoepithelial differentiation are characteristic of type P tumors arising in mice transgenic for Wnt1, neoplasms arising in mice infected by the MMTV, and spontaneous adenosquamous carcinomas; and third, 'carcinomas with epithelial to mesenchymal transition (EMT)' are a characteristic feature of tumor progression in Hras-, Myc-, and SV40-TAg-induced mammary neoplasms and PL/J and SJL/J mouse strains, and display de novo expression of myoepithelial and mesenchymal cell markers. In sharp contrast, EMT was not detected in papillary adenocarcinomas arising in BALB/cJ mice, spontaneous adenoacanthomas, neoplasms associated with MMTV-infection, or in neoplasms arising in mice transgenic for Neu and Wnt1. Immunohistochemical profiles of complex neoplasms are consistent with a stem cell origin, whereas simple carcinomas might originate from a cell committed to the

  11. Andrographolide induces autophagic cell death in human liver cancer cells through cyclophilin D-mediated mitochondrial permeability transition pore.

    Science.gov (United States)

    Chen, Wei; Feng, Lina; Nie, Hao; Zheng, Xiaodong

    2012-11-01

    Liver cancer is the third leading cause of cancer death worldwide and about half of the patients with liver cancer require adjuvant therapy after surgical resection. Therefore, development of novel agents to eradicate cancer cells may constitute a viable approach to treat patients with liver cancer. Andrographolide, a diterpenoid lactone isolated from Andrographis paniculata, is known to possess potent antioxidant, anti-inflammatory, antineoplastic and antiviral properties. In this study, we investigated the cytotoxic effect of andrographolide on human liver cancer cells and explored the cell death mechanism. Andrographolide induced a cell death distinct from apoptosis in multiple human liver cancer cells. The death was characterized by autophagy as evidenced by the accumulation of LC3 II and autophagosomes, and the formation of puncta GFP-LC3. This autophagy as well as cytotoxicity caused by andrographolide could be effectively prevented by 3-methyladenine (a chemical inhibitor of autophagy). Mechanistic study indicated that andrographolide induced autophagic cell death by disruption of mitochondrial transmembrane potential and elevation of reactive oxygen species, which were correlated with mitochondrial permeability transition pore Inhibition of cyclophilin D (a component of MPTP) by cyclosporin A or abrogation of its expression by small interfering RNA significantly suppressed the cytotoxicity of andrographolide, suggesting that cyclophilin D may play an important role in mediating andrographolide-induced cytotoxicity. Taken together, our findings unveil a novel mechanism of drug action by andrographolide in liver cancer cells and suggest that andrographolide may represent a promising novel agent in the treatment of liver cancer.

  12. Spontaneous vortex phase (SVP) of ruthenocuprate high Tc ...

    Indian Academy of Sciences (India)

    RuSr2(RE1.5Ce0.5)Cu2O10, has given rise to the concept of spontaneous vortex phase (SVP). In these compounds, the magnetic ordering temperature (Tmag >. 100 K) is higher than the superconducting transition temperature (Tc ~ 30 K). Hence, due to internal magnetic fields, these compounds remain in a spontaneous.

  13. Critical roles of p53 in epithelial-mesenchymal transition and metastasis of hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    Full Text Available Hepatocellular carcinoma (HCC is one of the most malignant tumors and the biggest obstacle in curing HCC is its high metastasis potential. Alteration of p53 is the most frequent genetic change found in HCC. Although the biological function of p53 in tumor initiation and progression has been well characterized, whether or not p53 is implicated in metastasis of HCC is largely unknown. In this study, we analyzed the potential functions of p53 in epithelial-mesenchymal transition (EMT and metastasis of HCC cells. Both insulin- and TGF-β1-induced changes of critical EMT markers were greatly enhanced by p53 knockdown in HCC cells. The insulin- and TGF-β1-stimulated migration of HCC cells were enhanced by p53 knockdown. Furthermore, in vivo metastasis of HCC cells using different mouse models was robustly enhanced by p53 knockdown. In addition, we found that p53 regulation on EMT and metastasis involves β-catenin signaling. The nuclear accumulation and transcriptional activity of β-catenin was modulated by p53. The enhanced EMT phenotype, cell migration and tumor metastasis of HCC cells by p53 knockdown were abrogated by inhibiting β-catenin signal pathway. In conclusion, this study reveals that p53 plays a pivotal role in EMT and metastasis of HCC cells via its regulation on β-catenin signaling.

  14. FRK inhibits breast cancer cell migration and invasion by suppressing epithelial-mesenchymal transition.

    Science.gov (United States)

    Ogunbolude, Yetunde; Dai, Chenlu; Bagu, Edward T; Goel, Raghuveera Kumar; Miah, Sayem; MacAusland-Berg, Joshua; Ng, Chi Ying; Chibbar, Rajni; Napper, Scott; Raptis, Leda; Vizeacoumar, Frederick; Vizeacoumar, Franco; Bonham, Keith; Lukong, Kiven Erique

    2017-12-22

    The human fyn-related kinase (FRK) is a non-receptor tyrosine kinase known to have tumor suppressor activity in breast cancer cells. However, its mechanism of action has not been fully characterized. We generated FRK-stable MDA-MB-231 breast cancer cell lines and analyzed the effect on cell proliferation, migration, and invasiveness. We also used kinome analysis to identify potential FRK-regulated signaling pathways. We employed both immunoblotting and RT-PCR to identify/validate FRK-regulated targets (proteins and genes) in these cells. Finally, we interrogated the TCGA and GENT gene expression databases to determine the correlation between the expression of FRK and epithelial/mesenchymal markers. We observed that FRK overexpression suppressed cell proliferation, migration, and invasiveness, inhibited various JAK/STAT, MAPK and Akt signaling pathways, and suppressed the expression of some STAT3 target genes. Also, FRK overexpression increased the expression of epithelial markers including E-cadherin mRNA and down-regulated the transcript levels of vimentin, fibronectin, and slug. Finally, we observed an inverse correlation between FRK expression and mesenchymal markers in a large cohort of breast cancer cells. Our data, therefore, suggests that FRK represses cell proliferation, migration and invasiveness by suppressing epithelial to mesenchymal transition.

  15. Human colorectal CD24+ cancer stem cells are susceptible to epithelial-mesenchymal transition.

    Science.gov (United States)

    Okano, Miho; Konno, Masamitsu; Kano, Yoshihiro; Kim, Hirotoshi; Kawamoto, Koichi; Ohkuma, Masahisa; Haraguchi, Naotsugu; Yokobori, Takehiko; Mimori, Koshi; Yamamoto, Hirofumi; Sekimoto, Mitsugu; Doki, Yuichiro; Mori, Masaki; Ishii, Hideshi

    2014-08-01

    Conventional cancer chemotherapy preferentially destroys non-stem cancer cells within a tumor, and a subpopulation of cancer stem cells (CSCs) is more resistant and survives, leading to relapses and metastasis. Howeve, recent studies suggest that CD24 and susceptibility to epithelial-mesenchymal transition (EMT) can serve as markers of CSCs. We report that CD24(+) cells are susceptible to induction of EMT, a phenotype important for cancer metastasis. We studied the responsiveness of CSC markers to TGF-β , an effective EMT inducer. The data on CD24 demonstrated that CD24(+) cells are susceptible to EMT, a phenotype important for cancer metastasis in two colorectal cancer cell lines, the CaR-1 and CCK81. CD24(+) cells expressed Notch 1 in response to exposure to TGF-β in culture and showed higher tumorigenic activity compared to controls. This evidence shows that CD24(+) cells are susceptible to EMT induction and to cancer progression and is indicative of the candidacy of CD24 as a therapeutic target in CSC.

  16. Role of epithelial-mesenchymal transition in the enrichment of colorectal cancer stem cells

    Directory of Open Access Journals (Sweden)

    Jia-ping CHENG

    2016-10-01

    Full Text Available Objective  To explore whether the enrichment of cancer stem cells (CSCs in colorectal cancer by suspension culture method is involved with epithelial-mesenchymal transition (EMT. Methods  3D microspheres were cultured by suspension culture method to human colorectal cancer SW620 cells. The 3D microspheres and SW620 cells were used as the research objects. To clarify whether 3D microspheres were enriched with CSCs, we made tumorigenicity experiments in NOD/SCID mice, soft agar cloning experiments, and detected the expression levels of cancer stem cells markers CD44 and Ep-CAM by flow cytometry or by Western blotting. The protein expression levels of EMT markers such as E-cadherin, N-cadherin and vimentin were detected by Western blotting. Results  Compared with the parental SW620 cells, colony formation in vitro (P<0.01 and tumorigenicity in NOD/SCID mice were significantly enhanced, the percentage of CD44-positive cells and Ep-CAM protein expression levels was significantly increased (P<0.01 in 3D microspheres. The protein expression level of epithelial marker E-cadherin was obviously increased (P<0.01, while the protein expression levels of mesenchymal markers N-cadherin and vimentin were significantly decreased (P<0.01. Conclusions  Colorectal cancer stem cells can be enriched by suspension culture method, and the process may be related to EMT. DOI: 10.11855/j.issn.0577-7402.2016.09.03

  17. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Second Results Report and Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2011-10-01

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. This is the second results report for the AT fuel cell bus since it was placed in service, and it focuses on the newest data analysis and lessons learned since the previous report. The appendices, referenced in the main report, provide the full background for the evaluation. They will be updated as new information is collected but will contain the original background material from the first report.

  18. Altered efficacy of AT1R-targeted treatment after spontaneous cancer cell-AT1R upregulation

    International Nuclear Information System (INIS)

    Ager, Eleanor I; Wen, Shu Wen; Chan, Joyna; Chong, Way W; Neo, Jaclyn H; Christophi, Christopher

    2011-01-01

    Targeting of the renin angiotensin system (RAS) reduces tumour growth in experimental models of cancer. We aimed to establish if combined targeting of the 'classical' and 'alternative' arms of the RAS could result in synergistic inhibition of colorectal cancer (CRC) liver metastases. Immediately following induction of CRC liver metastases through intrasplenic injection of murine CRC cells, treatment with irbesartan (AT1R blocker; 50 mg/kg/day s.c.), captopril (ACE inhibitor; 750 mg/kg/day i.p.), CGP42112A (AT2R agonist; 0.6 μg/kg/hr i.p.), and/or ANG-(1-7) (24 μg/kg/hr i.p.) began and continued for 21 days. Liver to body weight ratio and/or stereology were used as a measure of tumour burden. Immunohistochemistry was used to determine AT1R and VEGF expression as well as proliferation (Ki67), apoptosis (active caspase 3) and angiogenesis (CD34). Combined RAS therapies failed to improve upon single arm therapies. However, while irbesartan previously inhibited tumour growth in this model, in the current experiments irbesartan failed to affect tumour burden. Subsequent analysis showed a cancer-cell specific upregulation of the angiotensin II type I receptor (AT1R) in irbesartan-insensitive compared to irbesartan-sensitive tumours. The upregulation of AT1R was associated with an increase in proliferation and VEGF expression by cancer cells. While animals bearing irbesartan-sensitive tumours showed a marked decrease in the number of proliferating cells in the liver and VEGF-expressing infiltrating cells in the tumour following AT1R treatment, these were unchanged by treatment in animals bearing irbesartan-insensitive (high AT1R expressing) tumours. Although the results do not support increased efficacy of combined treatment, they provide intriguing evidence of the importance of RAS expression in determining patient response and tumour growth potential and suggest that components of the RAS could be used as biomarkers to aid in patient selection

  19. G9a Inhibition Induces Autophagic Cell Death via AMPK/mTOR Pathway in Bladder Transitional Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    Feng Li

    Full Text Available G9a has been reported to highly express in bladder transitional cell carcinoma (TCC and G9a inhibition significantly attenuates cell proliferation, but the underlying mechanism is not fully understood. The present study aimed at examining the potential role of autophagy in the anti-proliferation effect of G9a inhibition on TCC T24 and UMUC-3 cell lines in vitro. We found that both pharmaceutical and genetical G9a inhibition significantly attenuated cell proliferation by MTT assay, Brdu incorporation assay and colony formation assay. G9a inhibition induced autophagy like morphology as determined by transmission electron microscope and LC-3 fluorescence assay. In addition, autophagy flux was induced by G9a inhibition in TCC cells, as determined by p62 turnover assay and LC-3 turnover assay. The autophagy induced positively contributed to the inhibition of cell proliferation because the growth attenuation capacity of G9a inhibition was reversed by autophagy inhibitors 3-MA. Mechanically, AMPK/mTOR pathway was identified to be involved in the regulation of G9a inhibition induced autophagy. Intensively activating mTOR by Rheb overexpression attenuated autophagy and autophagic cell death induced by G9a inhibition. In addition, pre-inhibiting AMPK by Compound C attenuated autophagy together with the anti-proliferation effect induced by G9a inhibition while pre-activating AMPK by AICAR enhanced them. In conclusion, our results indicate that G9a inhibition induces autophagy through activating AMPK/mTOR pathway and the autophagy induced positively contributes to the inhibition of cell proliferation in TCC cells. These findings shed some light on the functional role of G9a in cell metabolism and suggest that G9a might be a therapeutic target in bladder TCC in the future.

  20. The mechanism of epithelial-mesenchymal transition induced by TGF-β1 in neuroblastoma cells.

    Science.gov (United States)

    Shao, Jing-Bo; Gao, Zhi-Mei; Huang, Wen-Yan; Lu, Zhi-Bao

    2017-05-01

    Neuroblastoma is the second most common extracranial malignant solid tumor that occurs in childhood, and metastasis is one of the major causes of death in neuroblastoma patients. The epithelial-mesenchymal transition (EMT) is an important mechanism for both the initiation of tumor invasion and subsequent metastasis. Therefore, this study investigated the mechanism by which transforming growth factor (TGF)-β1 induces EMT in human neuroblastoma cells. Using quantitative RT-qPCR and western blot analyses, we found that the mRNA and protein expression levels of E-cadherin were significantly decreased, whereas that of α-SMA was significantly increased after neuroblastoma cells were treated with different concentrations of TGF-β1. A scratch test and Transwell migration assay revealed that cell migration significantly and directly correlated with the concentration of TGF-β1 indicating that TGF-β1 induced EMT in neuroblastoma cells and led to their migration. Inhibiting Smad2/3 expression did not affect the expression of the key molecules involved in EMT. Further investigation found that the expression of the glioblastoma transcription factor (Gli) significantly increased in TGF-β1-stimulated neuroblastoma cells undergoing EMT, accordingly, interfering with Gli1/2 expression inhibited TGF-β1-induced EMT in neuroblastoma cells. GANT61, which is a targeted inhibitor of Gli1 and Gli2, decreased cell viability and promoted cell apoptosis. Thus, TGF-β1 induced EMT in neuroblastoma cells to increase their migration. Specifically, EMT induced by TGF-β1 in neuroblastoma cells did not depend on the Smad signaling pathway, and the transcription factor Gli participated in TGF-β1-induced EMT independent of Smad signaling.

  1. A 21-35 kDa Mixed Protein Component from Helicobacter pylori Activates Mast Cells Effectively in Chronic Spontaneous Urticaria.

    Science.gov (United States)

    Tan, Ran-Jing; Sun, He-Qiang; Zhang, Wei; Yuan, Han-Mei; Li, Bin; Yan, Hong-Tao; Lan, Chun-Hui; Yang, Jun; Zhao, Zhuo; Wu, Jin-Jin; Wu, Chao

    2016-12-01

    Helicobacter pylori (H. pylori) seem to involve in the etiology of chronic spontaneous urticaria (CSU). But studies of the pathogenic mechanism are very little. In this study, we detected the serum-specific anti-H. pylori IgG and IgE antibodies in 211 CSU and 137 normal subjects by enzyme-linked immunosorbent assay (ELISA), evaluated the direct activation effects of H. pylori preparations and its protein components on human LAD 2 mast cell line in vitro, and analyzed the specific protein ingredients and functions of the most effective H. pylori mixed protein component using liquid chromatography-mass spectrometry and ELISA assay. In CSU patients, the positive rate of anti-H. pylori IgG positive rate was significantly higher than that in normal controls, and the anti-H. pylori IgE levels had no statistical difference between H. pylori-infected patients with and without CSU. Further studies suggested that H. pylori preparations can directly activate human LAD 2 mast cell line in a dose-dependent manner and its most powerful protein component was a mixture of 21-35 kDa proteins. Moreover, the 21-35 kDa mixed protein component mainly contained 23 kinds of proteins, which can stimulate the release of histamine, TNF-a, IL-3, IFN-γ, and LTB4 by LAD 2 cells in a dose-dependent or time-dependent manner. A 21-35 kDa mixed protein component should be regarded as the most promising pathogenic factor contributing to the CSU associated with H. pylori infection. © 2016 John Wiley & Sons Ltd.

  2. NFBD1/MDC1 participates in the regulation of G2/M transition in mammalian cells

    International Nuclear Information System (INIS)

    Bu, Youquan; Suenaga, Yusuke; Okoshi, Rintaro; Sang, Meixiang; Kubo, Natsumi; Song, Fangzhou; Nakagawara, Akira; Ozaki, Toshinori

    2010-01-01

    NFBD1/MDC1 is a large nuclear protein involved in the early cellular response to DNA damage. Upon DNA damage, NFBD1 has an ability to facilitate the efficient DNA repair. In the present study, we have found that, in addition to DNA damage response, NFBD1 plays a critical role in the regulation of G2/M transition. Expression study using synchronized HeLa cells demonstrated that, like the mitotic kinase Plk1, NFBD1 expression level is maximal in G2/M-phase of the cell cycle. siRNA-mediated knockdown of NFBD1 resulted in G2/M arrest as well as simultaneous apoptosis in association with a significant increase in the amounts of γH2AX and pro-apoptotic p73. Since a remarkable down-regulation of mitotic phospho-histone H3 was detectable in NFBD1-knocked down cells, it is likely that knocking down of NFBD1 inhibits G2/M transition. Taken together, our present findings suggest that NFBD1 has a pivotal role in the regulation of proper mitotic entry.

  3. Clinical efficacy of omalizumab in chronic spontaneous urticaria is associated with a reduction of FcεRI-positive cells in the skin.

    Science.gov (United States)

    Metz, Martin; Staubach, Petra; Bauer, Andrea; Brehler, Randolf; Gericke, Janine; Kangas, Michael; Ashton-Chess, Joanna; Jarvis, Philip; Georgiou, Panayiotis; Canvin, Janice; Hillenbrand, Rainer; Erpenbeck, Veit J; Maurer, Marcus

    2017-01-01

    Background. Treatment with omalizumab, a humanized recombinant monoclonal anti-IgE antibody, results in clinical efficacy in patients with Chronic Spontaneous Urticaria (CSU). The mechanism of action of omalizumab in CSU has not been elucidated in detail. Objectives. To determine the effects of omalizumab on levels of high affinity IgE receptor-positive (FcεRI + ) and IgE-positive (IgE + ) dermal cells and blood basophils. Treatment efficacy and safety were also assessed. Study design. In a double-blind study, CSU patients aged 18‑75 years were randomized to receive 300 mg omalizumab (n=20) or placebo (n=10) subcutaneously every 4 weeks for 12 weeks. Changes in disease activity were assessed by use of the weekly Urticaria Activity Score (UAS7). Circulating IgE levels, basophil numbers and levels of expression of FcεRI + and IgE + cells in the skin and in blood basophils were determined. Results. Patients receiving omalizumab showed a significantly greater decrease in UAS7 compared with patients receiving placebo. At Week 12 the mean difference in UAS7 between treatment groups was -14.82 (p=0.0027), consistent with previous studies. Total IgE levels in serum were increased after omalizumab treatment and remained elevated up to Week 12. Free IgE levels decreased after omalizumab treatment. Mean levels of FcεRI + skin cells in patients treated with omalizumab 300 mg were decreased at Week 12 compared with baseline in the dermis of both non-lesional and lesional skin, reaching levels comparable with those seen in healthy volunteers (HVs). There were no statistically significant changes in mean FcɛRI + cell levels in the placebo group. Similar results were seen for changes in IgE + cells, although the changes were not statistically significant. The level of peripheral blood basophils increased immediately after treatment start and returned to Baseline values after the follow-up period. The levels of FcεRI and IgE expression on peripheral blood basophils were

  4. EML4-ALK induces epithelial–mesenchymal transition consistent with cancer stem cell properties in H1299 non-small cell lung cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Fuchun; Liu, Xiaoke, E-mail: liuxk57@163.com; Qing, Qin, E-mail: qinqingscu@126.com; Sang, Yaxiong, E-mail: yaxiongsang@gmail.com; Feng, Chengjun, E-mail: leymj@163.com; Li, Xiaoyu, E-mail: lixiaoyu2012huaxi@163.com; Jiang, Li, E-mail: summer.jl06@foxmail.com; Su, Pei, E-mail: keyanxiaozhu@163.com; Wang, Yongsheng, E-mail: wangys@scu.edu.cn

    2015-04-10

    The echinoderm microtubule-associated protein-like 4(EML4) – anaplastic lymphoma kinase (ALK) fusion gene has been identified as a driver mutation in non-small-cell lung cancer (NSCLC). However, the role of EML4-ALK in malignant transformation is not entirely clear. Here, for the first time, we showed that H1299 NSCLC cells stably expressing EML4-ALK acquire EMT phenotype, associated with enhanced invasive migration and increased expression of EMT-inducing transcription factors. H1299-EML4-ALK cells also displayed cancer stem cell-like properties with a concomitant up-regulation of CD133 and enhanced ability of mammospheres formation. Moreover, we found that inhibition of ERK1/2 reversed EMT induced by EML4-ALK in H1299 cells. Taken together, these results suggested that EML4-ALK induced ERK activation is mechanistically associated with EMT phenotype. Thus, inhibition of ERK signaling pathway could be a potential strategy in treatment of NSCLC patients with EML4-ALK translocation. - Highlights: • EML4-ALK induced epithelial–mesenchymal transition in H1299 cells. • Expression of EML4-ALK promotes invasion and migration in vitro. • EML4-ALK enhanced sphere formation and stem cell-like properties in H1299 cells. • Blockage of ERK1/2 reverse Epithelial–Mesenchymal transition induced by EML4-ALK.

  5. Tissue transglutaminase induces Epithelial-Mesenchymal-Transition and the acquisition of stem cell like characteristics in colorectal cancer cells.

    Science.gov (United States)

    Ayinde, Oluseyi; Wang, Zhuo; Griffin, Martin

    2017-03-21

    Human colon cancer cell lines (CRCs) RKO, SW480 and SW620 were investigated for TG2 involvement in tumour advancement and aggression. TG2 expression correlated with tumour advancement and expression of markers of epithelial-mesenchymal transition (EMT). The metastatic cell line SW620 showed high TG2 expression compared to the primary tumour cell lines SW480 and RKO and could form tumour spheroids under non- adherent conditions. TG2 manipulation in the CRCs by shRNA or TG2 transduction confirmed the relationship between TG2 and EMT. TGFβ1 expression in CRC cells, and its level in the cell medium and extracellular matrix was increased in primary tumour CRCs overexpressing TG2 and could regulate TG2 expression and EMT by both canonical (RKO) and non-canonical (RKO and SW480) signalling. TGFβ1 regulation was not observed in the metastatic SW620 cell line, but TG2 knockdown or inhibition in SW620 reversed EMT. In SW620, TG2 expression and EMT was associated with increased presence of nuclear β-catenin which could be mediated by association of TG2 with the Wnt signalling co-receptor LRP5. TG2 inhibition/knockdown increased interaction between β-catenin and ubiquitin shown by co-immunoprecipitation, suggesting that TG2 could be important in β-catenin regulation. β-Catenin and TG2 was also upregulated in SW620 spheroid cells enriched with cancer stem cell marker CD44 and TG2 inhibition/knockdown reduced the spheroid forming potential of SW620 cells. Our data suggests that TG2 could hold both prognostic and therapeutic significance in colon cancer.

  6. Andrographolide suppresses epithelial mesenchymal transition by inhibition of MAPK signalling pathway in lens epithelial cells.

    Science.gov (United States)

    Kayastha, Forum; Johar, Kaid; Gajjar, Devarshi; Arora, Anshul; Madhu, Hardik; Ganatra, Darshini; Vasavada, Abhay

    2015-06-01

    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. The purpose of this study is to evaluate the effect of andrographolide on EMT induced by growth factors in the fetal human lens epithelial cell line (FHL 124). Initially the LECs were treated with growth factors (TGF-beta 2 and bFGF) to induce EMT. Subsequently these EMT-induced cells were treated with andrographolide at 100 and 500 nM concentrations for 24 h. Our results showed that FHL 124 cells treated with growth factors had a significant decrease in protein and m-RNA levels of epithelial markers pax6 and E-Cadherin. After administering andrographolide, these levels significantly increased. It was noticed that EMT markers alpha-SMA, fibronectin and collagen IV significantly decreased after treatment with andrographolide when compared to the other group. Treatment with andrographolide significantly inhibited phosphorylation of ERK and JNK. Cell cycle analysis showed that andrographolide did not arrest cells at G0/G1 or G2/M at tested concentrations. Our findings suggest that andrographolide helps sustain epithelial characteristics by modulating EMT markers and inhibiting the mitogen-activated protein kinase (MAPK) signalling pathway in LECs. Hence it can prove to be useful in curbing EMT-mediated PCO.

  7. MiR-200c suppresses the migration of retinoblastoma cells by reversing epithelial mesenchymal transition

    Directory of Open Access Journals (Sweden)

    Xiao-Lei Shao

    2017-08-01

    Full Text Available AIM: To analyze the relationship between clinical features and epithelial mesenchymal transition (EMT in retinoblastoma (RB, further to investigate whether miR-200c regulates the EMT and migration of RB cells. METHODS: Expression of EMT-related markers and tumor-related factors were detected by immuno-histochemistry analysis in RB tissue from 29 cases. Correlations between their expression and clinical characteristics were analyzed. The regulation effects of miR-200c on EMT-related markers, tumor-related factors were observed in mRNA level and protein level by real-time polymerase chain reaction (PCR and Western blot, respectively, in Y79 and Weri-rb1 cells. Its effects on migration force of these RB cell lines were also detected with Transwell test. RESULTS: Lower expression of E-cadherin was present in the cases with malignant prognosis. MiR-200c promoted the expression of E-cadherin and decreased the expression of Vimentin and N-cadherin in Y79 and Weri-rb1 cells. Migration force of RB cells could be inhibited by miR-200c. CONCLUSION: EMT might be associated with bad prognosis in RB. MiR-200c suppresses the migration of retinoblastomatous cells by reverse EMT.

  8. Twist1-induced epithelial-mesenchymal transition according to microsatellite instability status in colon cancer cells.

    Science.gov (United States)

    Oh, Bo Young; Kim, So-Young; Lee, Yeo Song; Hong, Hye Kyung; Kim, Tae Won; Kim, Seok Hyung; Lee, Woo Yong; Cho, Yong Beom

    2016-08-30

    Colorectal cancer (CRC) with microsatellite instability (MSI) may exhibit impaired epithelial-mesenchymal transition (EMT), but little is known about the underlying mechanisms of this phenomenon. In this study, we investigated the role of Twist1 and its downstream signaling cascades in EMT induction according to MSI status. To investigate the effects of Twist1 on EMT induction according to MSI status, MSS LS513 and MSI LoVo colon cancer cell lines, which overexpress human Twist1, were generated. Twist1-induced EMT and its downstream signaling pathways were evaluated via in vitro and in vivo experiments. We found that Twist1 induced EMT markers and stem cell-like characteristics via AKT signaling pathways. Twist1 induced activation of AKT and suppression of glycogen synthase kinase (GSK)-3β, which resulted in the activation of β-catenin, increasing CD44 expression. In addition, Twist1 activated the AKT-induced NF-κB pathway, increasing CD44 and CD166 expression. Activation of both the AKT/GSK-3β/β-catenin and AKT/NF-κB pathways occurred in MSS LS513 cells, while only the AKT/GSK-3β/β-catenin pathway was activated in MSI LoVo cells. In conclusion, Twist1 induces stem cell-like characteristics in colon cancer cell lines related to EMT via AKT signaling pathways, and those pathways depend on MSI status.

  9. Lentiviral Vector Mediated Claudin1 Silencing Inhibits Epithelial to Mesenchymal Transition in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xianqi Zhao

    2015-06-01

    Full Text Available Breast cancer has a high incidence and mortality rate worldwide. Several viral vectors including lentiviral, adenoviral and adeno-associated viral vectors have been used in gene therapy for various forms of human cancer, and have shown promising effects in controlling tumor development. Claudin1 (CLDN1 is a member of the tetraspan transmembrane protein family that plays a major role in tight junctions and is associated with tumor metastasis. However, the role of CLDN1 in breast cancer is largely unexplored. In this study, we tested the therapeutic potential of silencing CLDN1 expression in two breast cancer (MDA-MB-231 and MCF7 cell lines using lentiviral vector mediated RNA interference. We found that a CLDN1 short hairpin (shRNA construct efficiently silenced CLDN1 expression in both breast cancer cell lines, and CLDN1 knockdown resulted in reduced cell proliferation, survival, migration and invasion. Furthermore, silencing CLDN1 inhibited epithelial to mesenchymal transition (EMT by upregulating the epithelial cell marker, E-cadherin, and downregulating mesenchymal markers, smooth muscle cell alpha-actin (SMA and Snai2. Our data demonstrated that lentiviral vector mediated CLDN1 RNA interference has great potential in breast cancer gene therapy by inhibiting EMT and controlling tumor cell growth.

  10. Imeglimin prevents human endothelial cell death by inhibiting mitochondrial permeability transition without inhibiting mitochondrial respiration.

    Science.gov (United States)

    Detaille, D; Vial, G; Borel, A-L; Cottet-Rouselle, C; Hallakou-Bozec, S; Bolze, S; Fouqueray, P; Fontaine, E

    2016-01-01

    Imeglimin is the first in a new class of oral glucose-lowering agents, having recently completed its phase 2b trial. As Imeglimin did show a full prevention of β-cell apoptosis, and since angiopathy represents a major complication of diabetes, we studied Imeglimin protective effects on hyperglycemia-induced death of human endothelial cells (HMEC-1). These cells were incubated in several oxidative stress environments (exposure to high glucose and oxidizing agent tert-butylhydroperoxide) which led to mitochondrial permeability transition pore (PTP) opening, cytochrome c release and cell death. These events were fully prevented by Imeglimin treatment. This protective effect on cell death occurred without any effect on oxygen consumption rate, on lactate production and on cytosolic redox or phosphate potentials. Imeglimin also dramatically decreased reactive oxygen species production, inhibiting specifically reverse electron transfer through complex I. We conclude that Imeglimin prevents hyperglycemia-induced cell death in HMEC-1 through inhibition of PTP opening without inhibiting mitochondrial respiration nor affecting cellular energy status. Considering the high prevalence of macrovascular and microvascular complications in type 2 diabetic subjects, these results together suggest a potential benefit of Imeglimin in diabetic angiopathy.

  11. Surgical management of bladder transitional cell carcinoma in a vesicular diverticulum: case report.

    LENUS (Irish Health Repository)

    Raheem, Omer A

    2012-02-01

    We report a case of primary transitional cell carcinoma (TCC) of a bladder diverticum along with a literature review. A 55-year-old male presented with painless gross hematuria. A histological diagnosis of TCC within a bladder diverticulum was made following cystoscopical examination. Initially transurethral resection of bladder tumour with subsequent intravesical chemotherapy followed. As a result of recurrence and in view of bladder-sparing therapy, a distal partial cystectomy was performed. This report demonstrates that conservative bladder-sparing treatment can be achieved and subsequently followed by vigilant cystoscopy.

  12. Surgical management of bladder transitional cell carcinoma in a vesicular diverticulum: case report.

    LENUS (Irish Health Repository)

    Raheem, Omer A

    2011-08-01

    We report a case of primary transitional cell carcinoma (TCC) of a bladder diverticum along with a literature review. A 55-year-old male presented with painless gross hematuria. A histological diagnosis of TCC within a bladder diverticulum was made following cystoscopical examination. Initially transurethral resection of bladder tumour with subsequent intravesical chemotherapy followed. As a result of recurrence and in view of bladder-sparing therapy, a distal partial cystectomy was performed. This report demonstrates that conservative bladder-sparing treatment can be achieved and subsequently followed by vigilant cystoscopy.

  13. Frequent mutations of chromatin remodeling genes in transitional cell carcinoma of the bladder

    DEFF Research Database (Denmark)

    Gui, Yaoting; Guo, Guangwu; Huang, Yi

    2011-01-01

    frequently in tumors of low stages and grades, highlighting its potential role in the classification and diagnosis of bladder cancer. Our results provide an overview of the genetic basis of TCC and suggest that aberration of chromatin regulation might be a hallmark of bladder cancer.......Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Here we sequenced the exomes of nine individuals with TCC and screened all the somatically mutated genes in a prevalence set of 88 additional individuals with TCC with different tumor stages and grades. In our study, we...

  14. Heterostructures of phosphorene and transition metal dichalcogenides for excitonic solar cells: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Vellayappan Dheivanayagam; Shen, Lei, E-mail: shenlei@nus.edu.sg [Engineering Science Programme, National University of Singapore, 9 Engineering Drive 1, Singapore 117575 (Singapore); Linghu, Jiajun; Zhang, Chun; Feng, Yuan Ping [Department of Physics, National University of Singapore, Singapore 117542 (Singapore)

    2016-03-21

    Using the many-body perturbation GW theory, we study the quasiparticle conduction-band offsets of phosphorene, a two-dimensional atomic layer of black phosphorus, and transition-metal dichalcogenides (TMDs). The calculated large exciton binding energies of phosphorene and TMDs indicate that their type-II heterostructures are suitable for excitonic thin-film solar cell applications. Our results show that these heterojunctions have a potential maximum power conversion efficiency of up to 12%, which can be further enhanced up to 20% by strain engineering.

  15. A novel derivative of doxorubicin, AD198, inhibits canine transitional cell carcinoma and osteosarcoma cells in vitro

    Directory of Open Access Journals (Sweden)

    Rathore K

    2015-09-01

    Full Text Available Kusum Rathore, Maria Cekanova Department of Small Animal Clinical Sciences, College of Veterinary Medicine, The University of Tennessee, Knoxville, TN, USA Abstract: Doxorubicin (DOX is one of the most commonly used chemotherapeutic treatments for a wide range of cancers. N-benzyladriamycin-14-valerate (AD198 is a lipophilic anthracycline that has been shown to target conventional and novel isoforms of protein kinase C (PKC in cytoplasm of cells. Because of the adverse effects of DOX, including hair loss, nausea, vomiting, liver dysfunction, and cardiotoxicity, novel derivatives of DOX have been synthesized and validated. In this study, we evaluated the effects of DOX and its derivative, AD198, on cell viability of three canine transitional cell carcinoma (K9TCC (K9TCC#1-Lillie, K9TCC#2-Dakota, K9TCC#4-Molly and three canine osteosarcoma (K9OSA (K9OSA#1-Zoe, K9OSA#2-Nashville, K9OSA#3-JJ primary cancer cell lines. DOX and AD198 significantly inhibited cell proliferation in all tested K9TCC and K9OSA cell lines in a dose-dependent manner. AD198 inhibited cell viability of tested K9TCC and K9OSA cell lines more efficiently as compared to DOX at the same concentration using MTS (3-(4,5-dimethyl-2-yl-5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl-2h-tetrazolium assay. AD198 had lower IC50 values as compared to DOX for all tested K9TCC and K9OSA cell lines. In addition, AD198 increased apoptosis in all tested K9TCC and K9OSA cell lines. AD198 increased the caspase activity in tested K9TCC and K9OSA cell lines, which was confirmed by caspase-3/7 assay, and cleavage of poly (ADP-ribose polymerase (PARP was confirmed by Western blotting analysis. In addition, AD198 cleaved PKC-δ, which subsequently activated the p38 signaling pathway, resulting in the apoptosis of tested K9TCC and K9OSA cell lines. Inhibition of the p38 signaling pathway by SB203580 rescued DOX- and AD198-induced apoptosis in tested K9TCC and K9OSA cell lines. Our in vitro results suggest

  16. Evidence for epithelial-mesenchymal transition in cancer stem cells of head and neck squamous cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Chao Chen

    Full Text Available Initiation, growth, recurrence, and metastasis of head and neck squamous cell carcinomas (HNSCC have been related to the behavior of cancer stem cells (CSC that can be identified by their aldehyde-dehydrogenase-isoform-1 (ALDH1 activity. We quantified and enriched ALDH1(+ cells within HNSCC cell lines and subsequently characterized their phenotypical and functional properties like invasion capacity and epithelial-mesenchymal transition (EMT. Spheroid culture enriched CSC from five HNSCC cell lines by up to 5-fold. In spheroid-derived cells (SDC and the parental monolayer-derived cell line ALDH1, CD44, CD24, E-Cadherin, α-SMA, and Vimentin expression was compared by flow-cytometry and immunofluorescence together with proliferation and cell cycle analysis. Invasion activity was evaluated by Matrigel assay and expression of stemness-related transcription factors (TF Nanog, Oct3/4, Sox2 and EMT-related genes Snail1 and 2, and Twist by real-time PCR. All cell lines formed spheroids that could self-renew and be serially re-passaged. ALDH1 expression was significantly higher in SDC. ALDH1(+ cells showed increased colony-formation. The proportion of cells with a putative CSC marker constellation of CD44(+/CD24(- was highly variable (0.5% to 96% in monolayer and spheroid cultures and overlapped in 0%-33% with the CD44(+/CD24(-/ALDH1(+ cell subset. SDC had significantly higher invading activity. mRNA of the stemness-related genes Sox2, Nanog, and Oct3/4 was significantly increased in SDC of all cell lines. Twist was significantly increased in two while Snail2 showed a significant increase in one and a significant decrease in SDC of two cell lines. SDC had a higher G0 phase proportion, showed high-level expression of α-SMA and Vimentin, but significantly decreased E-Cadherin expression. HNSCC-lines harbor potential CSC, characterized by ALDH1 and stemness marker TF expression as well as properties like invasiveness, quiescence, and EMT. CSC can be

  17. Tissue transglutaminase promotes drug resistance and invasion by inducing mesenchymal transition in mammary epithelial cells.

    Directory of Open Access Journals (Sweden)

    Anupam Kumar

    Full Text Available Recent observations that aberrant expression of tissue transglutaminase (TG2 promotes growth, survival, and metastasis of multiple tumor types is of great significance and could yield novel therapeutic targets for improved patient outcomes. To accomplish this, a clear understanding of how TG2 contributes to these phenotypes is essential. Using mammary epithelial cell lines (MCF10A, MCF12A, MCF7 and MCF7/RT as a model system, we determined the impact of TG2 expression on cell growth, cell survival, invasion, and differentiation. Our results show that TG2 expression promotes drug resistance and invasive functions by inducing epithelial-mesenchymal transition (EMT. Thus, TG2 expression supported anchorage-independent growth of mammary epithelial cells in soft-agar, disrupted the apical-basal polarity, and resulted in disorganized acini structures when grown in 3D-culture. At molecular level, TG2 expression resulted in loss of E-cadherin and increased the expression of various transcriptional repressors (Snail1, Zeb1, Zeb2 and Twist1. Tumor growth factor-beta (TGF-β failed to induce EMT in cells lacking TG2 expression, suggesting that TG2 is a downstream effector of TGF-β-induced EMT. Moreover, TG2 expression induced stem cell-like phenotype in mammary epithelial cells as revealed by enrichment of CD44(+/CD24(-/low cell populations. Overall, our studies show that aberrant expression of TG2 is sufficient for inducing EMT in epithelial cells and establish a strong link between TG2 expression and progression of metastatic breast disease.

  18. Suitable parameter choice on quantitative morphology of A549 cell in epithelial–mesenchymal transition

    Science.gov (United States)

    Ren, Zhou-Xin; Yu, Hai-Bin; Li, Jian-Sheng; Shen, Jun-Ling; Du, Wen-Sen

    2015-01-01

    Evaluation of morphological changes in cells is an integral part of study on epithelial to mesenchymal transition (EMT), however, only a few papers reported the changes in quantitative parameters and no article compared different parameters for demanding better parameters. In the study, the purpose was to investigate suitable parameters for quantitative evaluation of EMT morphological changes. A549 human lung adenocarcinoma cell line was selected for the study. Some cells were stimulated by transforming growth factor-β1 (TGF-β1) for EMT, and other cells were as control without TGF-β1 stimulation. Subsequently, cells were placed in phase contrast microscope and three arbitrary fields were captured and saved with a personal computer. Using the tools of Photoshop software, some cells in an image were selected, segmented out and exchanged into unique hue, and other part in the image was shifted into another unique hue. The cells were calculated with 29 morphological parameters by Image Pro Plus software. A parameter between cells with or without TGF-β1 stimulation was compared statistically and nine parameters were significantly different between them. Receiver operating characteristic curve (ROC curve) of a parameter was described with SPSS software and F-test was used to compare two areas under the curves (AUCs) in Excel. Among them, roundness and radius ratio were the most AUCs and were significant higher than the other parameters. The results provided a new method with quantitative assessment of cell morphology during EMT, and found out two parameters, roundness and radius ratio, as suitable for quantification. PMID:26182364

  19. Drosophila p115 is required for Cdk1 activation and G2/M cell cycle transition.

    Science.gov (United States)

    Ibar, Consuelo; Glavic, Álvaro

    2017-04-01

    Golgi complex inheritance and its relationship with the cell cycle are central in cell biology. Golgi matrix proteins, known as golgins, are one of the components that underlie the shape and functionality of this organelle. In mammalian cells, golgins are phosphorylated during mitosis to allow fragmentation of the Golgi ribbon and they also participate in spindle dynamics; both processes are required for cell cycle progression. Little is known about the function of golgins during mitosis in metazoans in vivo. This is particularly significant in Drosophila, in which the Golgi architecture is distributed in numerous units scattered throughout the cytoplasm, in contrast with mammalian cells. We examined the function of the ER/cis-Golgi golgin p115 during the proliferative phase of the Drosophila wing imaginal disc. Knockdown of p115 decreased tissue size. This phenotype was not caused by programmed cell death or cell size reductions, but by a reduction in the final cell number due to an accumulation of cells at the G2/M transition. This phenomenon frequently allows mitotic bypass and re-replication of DNA. These outcomes are similar to those observed following the partial loss of function of positive regulators of Cdk1 in Drosophila. In agreement with this, Cdk1 activation was reduced upon p115 knockdown. Interestingly, these phenotypes were fully rescued by Cdk1 overexpression and partially rescued by Myt1 depletion, but not by String (also known as Cdc25) overexpression. Additionally, we confirmed the physical interaction between p115 and Cdk1, suggesting that the formation of a complex where both proteins are present is essential for the full activation of Cdk1 and thus the correct progression of mitosis in proliferating tissues. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. ZEB1 Promotes Oxaliplatin Resistance through the Induction of Epithelial - Mesenchymal Transition in Colon Cancer Cells.

    Science.gov (United States)

    Guo, Cao; Ma, Junli; Deng, Ganlu; Qu, Yanlin; Yin, Ling; Li, Yiyi; Han, Ying; Cai, Changjing; Shen, Hong; Zeng, Shan

    2017-01-01

    Background: Oxaliplatin (OXA) chemotherapy is widely used in the clinical treatment of colon cancer. However, chemo-resistance is still a barrier to effective chemotherapy in cases of colon cancer. Accumulated evidence suggests that the epithelial mesenchymal transition (EMT) may be a critical factor in chemo-sensitivity. The present study investigated the effects of Zinc finger E-box binding homeobox 1 (ZEB1) on OXA-sensitivity in colon cancer cells. Method: ZEB1expression and its correlation with clinicopathological characteristics were analyzed using tumor tissue from an independent cohort consisting of 118 colon cancer (CC) patients who receiving OXA-based chemotherapy. ZEB1 modulation of OXA-sensitivity in colon cancer cells was investigated in a OXA-resistant subline of HCT116/OXA cells and the parental colon cancer cell line: HCT116. A CCK8 assay was carried out to determine OXA-sensitivity. qRT-PCR, Western blot, Scratch wound healing and transwell assays were used to determine EMT phenotype of colon cells. ZEB1 knockdown using small interfering RNA (siRNA) was used to determine the ZEB1 contribution to OXA-sensitivity in vitro and in vivo (in a nude mice xenograft model). Result: ZEB1 expression was significantly increased in colon tumor tissue, and was correlated with lymph node metastasis and the depth of invasion. Compared with the parental colon cancer cells (HCT116), HCT116/OXA cells exhibited an EMT phenotype characterized by up-regulated expression of ZEB1, Vimentin, MMP2 and MMP9, but down-regulated expression of E-cadherin. Transfection of Si-ZEB1 into HCT116/OXA cells significantly reversed the EMT phenotype and enhanced OXA-sensitivity in vitro and in vivo . Conclusion: HCT116/OXA cells acquired an EMT phenotype. ZEB1 knockdown effectively restored OXA-sensitivity by reversing EMT. ZEB1 is a potential therapeutic target for the prevention of OXA-resistance in colon cancer.

  1. Prevention of spontaneous autoimmune diabetes in NOD mice by transferring in vitro antigen-pulsed syngeneic dendritic cells

    DEFF Research Database (Denmark)

    Papaccio, G; Nicoletti, F; Pisanti, F A

    2000-01-01

    To evaluate the effect of antigen-pulsed dendritic cell (DC) transfer on the development of diabetes, 5-week-old female NOD mice received a single iv injection of splenic syngeneic DC from euglycemic NOD mice pulsed in vitro with human y globulin (HGG). Eleven of 12 mice were protected from the d...... exogenous IL-4 and IL-10 exert antidiabetogenic effect in NOD mice and early blockade of endogenous tumor necrosis factor-alpha prevents NOD mouse diabetes, these phenomena may be causally related to the antidiabetogenic effect of HGG-pulsed DC treatment....... the development of diabetes up to the age of 25 weeks, and the insulitis score was significantly reduced. In contrast, NOD mice receiving unpulsed splenic DCs showed histological signs of insulitis and course of type 1 diabetes similar to untreated NOD mice. Treatment with HGG-pulsed DC was associated...

  2. Spontaneous Differentiation of Human Mesenchymal Stem Cells on Poly-Lactic-Co-Glycolic Acid Nano-Fiber Scaffold.

    Directory of Open Access Journals (Sweden)

    Koshiro Sonomoto

    Full Text Available Mesenchymal stem cells (MSCs have immunosuppressive activity and can differentiate into bone and cartilage; and thus seem ideal for treatment of rheumatoid arthritis (RA. Here, we investigated the osteogenesis and chondrogenesis potentials of MSCs seeded onto nano-fiber scaffolds (NFs in vitro and possible use for the repair of RA-affected joints.MSCs derived from healthy donors and patients with RA or osteoarthritis (OA were seeded on poly-lactic-glycolic acid (PLGA electrospun NFs and cultured in vitro.Healthy donor-derived MSCs seeded onto NFs stained positive with von Kossa at Day 14 post-stimulation for osteoblast differentiation. Similarly, MSCs stained positive with Safranin O at Day 14 post-stimulation for chondrocyte differentiation. Surprisingly, even cultured without any stimulation, MSCs expressed RUNX2 and SOX9 (master regulators of bone and cartilage differentiation at Day 7. Moreover, MSCs stained positive for osteocalcin, a bone marker, and simultaneously also with Safranin O at Day 14. On Day 28, the cell morphology changed from a spindle-like to an osteocyte-like appearance with processes, along with the expression of dentin matrix protein-1 (DMP-1 and matrix extracellular phosphoglycoprotein (MEPE, suggesting possible differentiation of MSCs into osteocytes. Calcification was observed on Day 56. Expression of osteoblast and chondrocyte differentiation markers was also noted in MSCs derived from RA or OA patients seeded on NFs. Lactic acid present in NFs potentially induced MSC differentiation into osteoblasts.Our PLGA scaffold NFs induced MSC differentiation into bone and cartilage. NFs induction process resembled the procedure of endochondral ossification. This finding indicates that the combination of MSCs and NFs is a promising therapeutic technique for the repair of RA or OA joints affected by bone and cartilage destruction.

  3. The role of Bgl2p in the transition to filamentous cells during biofilm formation by Candida albicans.

    Science.gov (United States)

    Chen, Xinyue; Zhang, Ruoyu; Takada, Ayako; Iwatani, Shun; Oka, Chiemi; Kitamoto, Toshitaka; Kajiwara, Susumu

    2017-02-01

    The fungal pathogen Candida albicans undergoes a transition from yeast cells to filamentous cells that is related to its pathogenicity. The complex multicellular processes involved in biofilm formation by this fungus also include this transition. In this work, we investigated the morphological role of the Bgl2 protein (Bgl2p) in the transition to filamentous cells during biofilm formation by C. albicans. Bgl2p has been identified as a β-1, 3-glucosyltransferase, and transcription of the CaBGL2 gene is upregulated during biofilm formation. We used scanning electron microscopy to observe the microstructure of a bgl2 null mutant during biofilm formation and found a delay in the transition to filamentous cells in the premature phase (24 hours) of biofilm formation. Deletion of the CaBGL2 gene led to a decrease in the expression of CPH2 and TEC1, which encode transcription factors required for the transition to the filamentous form. These findings indicate that Bgl2p plays a role in the transition to filamentous cells during biofilm formation by C. albicans. © 2016 Blackwell Verlag GmbH.

  4. TRPM5 mediates acidic extracellular pH signaling and TRPM5 inhibition reduces spontaneous metastasis in mouse B16-BL6 melanoma cells

    Science.gov (United States)

    Maeda, Toyonobu; Suzuki, Atsuko; Koga, Kaori; Miyamoto, Chihiro; Maehata, Yojiro; Ozawa, Shigeyuki; Hata, Ryu-Ichiro; Nagashima, Yoji; Nabeshima, Kazuki; Miyazaki, Kaoru; Kato, Yasumasa

    2017-01-01

    Extracellular acidity is a hallmark of solid tumors and is associated with metastasis in the tumor microenvironment. Acidic extracellular pH (pHe) has been found to increase intracellular Ca2+ and matrix metalloproteinase-9 (MMP-9) expression by activating NF-κB in the mouse B16 melanoma model. The present study assessed whether TRPM5, an intracellular Ca2+-dependent monovalent cation channel, is associated with acidic pHe signaling and induction of MMP-9 expression in this mouse melanoma model. Treatment of B16 cells with Trpm5 siRNA reduced acidic pHe-induced MMP-9 expression. Enforced expression of Trpm5 increased the rate of acidic pHe-induced MMP-9 expression, as well as increasing experimental lung metastasis. This genetic manipulation did not alter the pHe critical for MMP-9 induction but simply amplified the percentage of inducible MMP-9 at each pHe. Treatment of tumor bearing mice with triphenylphosphine oxide (TPPO), an inhibitor of TRPM5, significantly reduced spontaneous lung metastasis. In silico analysis of clinical samples showed that high TRPM5 mRNA expression correlated with poor overall survival rate in patients with melanoma and gastric cancer but not in patients with cancers of the ovary, lung, breast, and rectum. These results showed that TRPM5 amplifies acidic pHe signaling and may be a promising target for preventing metastasis of some types of tumor. PMID:29108231

  5. Daily Coffee Intake Inhibits Pancreatic Beta Cell Damage and Nonalcoholic Steatohepatitis in a Mouse Model of Spontaneous Metabolic Syndrome, Tsumura-Suzuki Obese Diabetic Mice.

    Science.gov (United States)

    Watanabe, Syunsuke; Takahashi, Tetsuyuki; Ogawa, Hirohisa; Uehara, Hisanori; Tsunematsu, Takaaki; Baba, Hayato; Morimoto, Yuki; Tsuneyama, Koichi

    2017-05-01

    Metabolic syndrome is one of the most important health issues worldwide. Obesity causes insulin resistance, hyperlipidemia, diabetes, and various diseases throughout the body. The liver phenotype, which is called nonalcoholic steatohepatitis (NASH), frequently progresses to hepatocellular carcinoma. We recently established a new animal model, Tsumura-Suzuki obese diabetic (TSOD) mice, which spontaneously exhibit obesity, diabetes, hyperlipidemia, and NASH with liver nodules. We examined the effects of coffee intake on various conditions of the metabolic syndrome using TSOD mice. The daily volume of coffee administered was limited so that it reflected the appropriate quantities consumed in humans. To clarify the effects of the specific components, animals were divided into two coffee-intake groups that included with and without caffeine. Coffee intake did not significantly affect obesity and hyperlipidemia in TSOD mice. In contrast, coffee intake caused various degrees of improvement in the pancreatic beta cell damage and steatohepatitis with liver carcinogenesis. Most of the effects were believed to be caused by a synergistic effect of caffeine with other components such as polyphenols. However, the antifibrotic effects of coffee appeared to be due to the polyphenols rather than the caffeine. A daily habit of drinking coffee could possibly play a role in the prevention of metabolic syndrome.

  6. TRPM5 mediates acidic extracellular pH signaling and TRPM5 inhibition reduces spontaneous metastasis in mouse B16-BL6 melanoma cells.

    Science.gov (United States)

    Maeda, Toyonobu; Suzuki, Atsuko; Koga, Kaori; Miyamoto, Chihiro; Maehata, Yojiro; Ozawa, Shigeyuki; Hata, Ryu-Ichiro; Nagashima, Yoji; Nabeshima, Kazuki; Miyazaki, Kaoru; Kato, Yasumasa

    2017-10-03

    Extracellular acidity is a hallmark of solid tumors and is associated with metastasis in the tumor microenvironment. Acidic extracellular pH (pH e ) has been found to increase intracellular Ca 2+ and matrix metalloproteinase-9 (MMP-9) expression by activating NF-κB in the mouse B16 melanoma model. The present study assessed whether TRPM5, an intracellular Ca 2+ -dependent monovalent cation channel, is associated with acidic pH e signaling and induction of MMP-9 expression in this mouse melanoma model. Treatment of B16 cells with Trpm5 siRNA reduced acidic pH e -induced MMP-9 expression. Enforced expression of Trpm5 increased the rate of acidic pH e -induced MMP-9 expression, as well as increasing experimental lung metastasis. This genetic manipulation did not alter the pH e critical for MMP-9 induction but simply amplified the percentage of inducible MMP-9 at each pH e . Treatment of tumor bearing mice with triphenylphosphine oxide (TPPO), an inhibitor of TRPM5, significantly reduced spontaneous lung metastasis. In silico analysis of clinical samples showed that high TRPM5 mRNA expression correlated with poor overall survival rate in patients with melanoma and gastric cancer but not in patients with cancers of the ovary, lung, breast, and rectum. These results showed that TRPM5 amplifies acidic pH e signaling and may be a promising target for preventing metastasis of some types of tumor.

  7. Proteome-wide analysis of neural stem cell differentiation to facilitate transition to cell replacement therapies

    Czech Academy of Sciences Publication Activity Database

    Žižková, Martina; Suchá, Rita; Tylečková, Jiřina; Jarkovská, Karla; Mairychová, Kateřina; Kotrčová, Eva; Marsala, M.; Gadher, S. J.; Kovářová, Hana

    2015-01-01

    Roč. 12, č. 1 (2015), s. 83-95 ISSN 1478-9450 R&D Projects: GA MŠk ED2.1.00/03.0124; GA TA ČR(CZ) TA01011466 Institutional support: RVO:67985904 Keywords : cell therapy * immunomodulation * neural stem cell differentiation * neural subpopulation * neurodegenerative disease Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.465, year: 2015

  8. Copper is an endogenous modulator of neural circuit spontaneous activity.

    Science.gov (United States)

    Dodani, Sheel C; Firl, Alana; Chan, Jefferson; Nam, Christine I; Aron, Allegra T; Onak, Carl S; Ramos-Torres, Karla M; Paek, Jaeho; Webster, Corey M; Feller, Marla B; Chang, Christopher J

    2014-11-18

    For reasons that remain insufficiently understood, the brain requires among the highest levels of metals in the body for normal function. The traditional paradigm for this organ and others is that fluxes of alkali and alkaline earth metals are required for signaling, but transition metals are maintained in static, tightly bound reservoirs for metabolism and protection against oxidative stress. Here we show that copper is an endogenous modulator of spontaneous activity, a property of functional neural circuitry. Using Copper Fluor-3 (CF3), a new fluorescent Cu(+) sensor for one- and two-photon imaging, we show that neurons and neural tissue maintain basal stores of loosely bound copper that can be attenuated by chelation, which define a labile copper pool. Targeted disruption of these labile copper stores by acute chelation or genetic knockdown of the CTR1 (copper transporter 1) copper channel alters the spatiotemporal properties of spontaneous activity in developing hippocampal and retinal circuits. The data identify an essential role for copper neuronal function and suggest broader contributions of this transition metal to cell signaling.

  9. Epithelial to mesenchymal transition by TGFβ-1 induction increases stemness characteristics in primary non small cell lung cancer cell line.

    Directory of Open Access Journals (Sweden)

    Giuseppe Pirozzi

    Full Text Available Cancer Stem Cells (CSCs hypothesis asserts that only a small subset of cells within a tumour is capable of both tumour initiation and sustainment. The Epithelial-Mesenchymal Transition (EMT is an embryonic developmental program that is often activated during cancer invasion and metastasis. The aim of this study is to shed light on the relationship between EMT and CSCs by using LC31 lung cancer primary cell line.A549 and LC31 cell lines were treated with 2 ng/ml TGFβ-1 for 30 days, and 80 days, respectively. To evaluate EMT, morphological changes were assessed by light microscopy, immunofluorescence and cytometry for following markers: cytokeratins, e-cadherin, CD326 (epithelial markers and CD90, and vimentin (mesenchymal markers. Moreover, RT-PCR for Slug, Twist and β-catenin genes were performed. On TGFβ-1 treated and untreated LC31 cell lines, we performed stemness tests such as pneumospheres growth and stem markers expression such as Oct4, Nanog, Sox2, c-kit and CD133. Western Blot for CD133 and tumorigenicity assays using NOD/SCID mice were performed.TGFβ-1 treated LC31 cell line lost its epithelial morphology assuming a fibroblast-like appearance. The same results were obtained for the A549 cell line (as control. Immunofluorescence and cytometry showed up-regulation of vimentin and CD90 and down-regulation of cytocheratin, e-cadherin and CD326 in TGFβ-1 treated LC31 and A549 cell lines. Slug, Twist and β-catenin m-RNA transcripts were up-regulated in TGFβ-1 treated LC31 cell line confirming EMT. This cell line showed also over-expression of Oct4, Nanog, Sox2 and CD133, all genes of stemness. In addition, in TGFβ-1 treated LC31 cell line, an increased pneumosphere-forming capacity and tumours-forming ability in NOD/SCID mice were detectable.The induction of EMT by TGFβ-1 exposure, in primary lung cancer cell line results in the acquisition of mesenchymal profile and in the expression of stem cell markers.

  10. Radiosensitivity and capacity for radiation-induced sublethal damage repair of canine transitional cell carcinoma (TCC) cell lines.

    Science.gov (United States)

    Parfitt, S L; Milner, R J; Salute, M E; Hintenlang, D E; Farese, J P; Bacon, N J; Bova, F J; Rajon, D A; Lurie, D M

    2011-09-01

    Understanding the inherent radiosensitivity and repair capacity of canine transitional cell carcinoma (TCC) can aid in optimizing radiation protocols to treat this disease. The objective of this study was to evaluate the parameters surviving fraction at 2 Gy (SF(2) ), α/β ratio and capacity for sublethal damage repair (SLDR) in response to radiation. Dose-response and split-dose studies were performed using the clonogenic assay. The mean SF(2) for three established TCC cell lines was high at 0.61. All the three cell lines exhibited a low to moderate α/β ratio, with the mean being 3.27. Two cell lines exhibited statistically increased survival at 4 and 24 h in the dose-response assay. Overall, our results indicate that the cell lines are moderately radioresistant, have a high repair capacity and behave similarly to a late-responding normal tissue. These findings indicate that the radiation protocols utilizing higher doses with less fractionation may be more effective for treating TCC. © 2011 Blackwell Publishing Ltd.

  11. SOX4 contributes to TGF-β-induced epithelial–mesenchymal transition and stem cell characteristics of gastric cancer cells

    Directory of Open Access Journals (Sweden)

    Xudong Peng

    2018-03-01

    Full Text Available SOX4 is highly expressed in gastric cancer (GC and is associated with tumor grade, metastasis and prognosis, however the mechanism is not clear. We report herein that SOX4 was upregulated and overexpression of SOX4 was associated with increased expression of the markers of Epithelial–mesenchymal transition (EMT and stemness in clinic patient samples. In vitro, overexpression of SOX4 promoted the invasion as showed by Transwell assay and stemness of GC cells as assessed by sphere formation assay, which was suppressed by silencing SOX4 with shRNA. Further studies showed that SOX4 up-regulated the expression of EMT transcription factors Twist1, snail1 and zeb1 and stemness transcription factors SOX2 and OCT4, and promoted the nuclear translocation of β-catenin. Moreover, we revealed that TGF-β treatment significantly up-regulated the expression of SOX4 and silencing SOX4 reversed TGF-β induced invasion and sphere formation ability of GC cells. Finally, we showed that SOX4 promoted the lung metastasis and tumor formation ability of gastric cancer cells in nude mice. Our results suggest that SOX4 is a target TGF-β signaling and mediates TGF-β-induced EMT and stem cell characteristics of GC cells, revealing a novel role of TGF-β/SOX4 axis in the regulation of malignant behavior of GC.

  12. Spontaneous uterine rupture

    African Journals Online (AJOL)

    ABSTRACT. Rupture of a gravid uterus is a surgical emergency. Predisposing factors include a scarred uterus. Spontaneous rupture of an unscarred uterus during pregnancy is a rare occurrence. We hereby present the case of a spontaneous complete uterine rupture at a gestational age of 34 weeks in a 35 year old patient ...

  13. Spontaneous intracranial hypotension.

    LENUS (Irish Health Repository)

    Fullam, L

    2012-01-31

    INTRODUCTION: Spontaneous\\/primary intracranial hypotension is characterised by orthostatic headache and is associated with characteristic magnetic resonance imaging findings. CASE REPORT: We present a case report of a patient with typical symptoms and classical radiological images. DISCUSSION: Spontaneous intracranial hypotension is an under-recognised cause of headache and can be diagnosed by history of typical orthostatic headache and findings on MRI brain.

  14. Epithelial-mesenchymal transition in breast epithelial cells treated with cadmium and the role of Snail.

    Science.gov (United States)

    Wei, Zhengxi; Shan, Zhongguo; Shaikh, Zahir A

    2018-04-01

    Epidemiological and experimental studies have implicated cadmium (Cd) with breast cancer. In breast epithelial MCF10A and MDA-MB-231 cells, Cd has been shown to promote cell growth. The present study examined whether Cd also promotes epithelial-mesenchymal transition (EMT), a hallmark of cancer progression. Human breast epithelial cells consisting of non-cancerous MCF10A, non-metastatic HCC 1937 and HCC 38, and metastatic MDA-MB-231 were treated with 1 or 3 μM Cd for 4 weeks. The MCF10A epithelial cells switched to a more mesenchymal-like morphology, which was accompanied by a decrease in the epithelial marker E-cadherin and an increase in the mesenchymal markers N-cadherin and vimentin. In both non-metastatic HCC 1937 and HCC 38 cells, treatment with Cd decreased the epithelial marker claudin-1. In addition, E-cadherin also decreased in the HCC 1937 cells. Even the mesenchymal-like MDA-MB-231 cells exhibited an increase in the mesenchymal marker vimentin. These changes indicated that prolonged treatment with Cd resulted in EMT in both normal and cancer-derived breast epithelial cells. Furthermore, both the MCF10A and MDA-MB-231 cells labeled with Zcad, a dual sensor for tracking EMT, demonstrated a decrease in the epithelial marker E-cadherin and an increase in the mesenchymal marker ZEB-1. Treatment of cells with Cd significantly increased the level of Snail, a transcription factor involved in the regulation of EMT. However, the Cd-induced Snail expression was completely abolished by actinomycin D. Luciferase reporter assay indicated that the expression of Snail was regulated by Cd at the promotor level. Snail was essential for Cd-induced promotion of EMT in the MDA-MB-231 cells, as knockdown of Snail expression blocked Cd-induced cell migration. Together, these results indicate that Cd promotes EMT in breast epithelial cells and does so by modulating the transcription of Snail. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Sperm associated antigen 9 plays an important role in bladder transitional cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Deepika Kanojia

    Full Text Available BACKGROUND: Majority of bladder cancer deaths are caused due to transitional cell carcinoma (TCC which is the most prevalent and chemoresistant malignancy of urinary bladder. Therefore, we analyzed the role of Sperm associated antigen 9 (SPAG9 in bladder TCC. METHODOLOGY AND FINDINGS: We examined SPAG9 expression and humoral response in 125 bladder TCC patients. Four bladder cancer cell lines were assessed for SPAG9 expression. In addition, we investigated the effect of SPAG9 ablation on cellular proliferation, cell cycle, migration and invasion in UM-UC-3 bladder cancer cells by employing gene silencing approach. Our SPAG9 gene and protein expression analysis revealed SPAG9 expression in 81% of bladder TCC tissue specimens. High SPAG9 expression (>60% SPAG9 positive cells was found to be significantly associated with superficial non-muscle invasive stage (P = 0.042 and low grade tumors (P = 0.002 suggesting SPAG9 putative role in early spread and tumorigenesis. Humoral response against SPAG9 was observed in 95% of patients found positive for SPAG9 expression. All four bladder cancer cell lines revealed SPAG9 expression. In addition, SPAG9 gene silencing in UM-UC-3 cells resulted in induction of G0-G1 arrest characterized by up-regulation of p16 and p21 and consequent down-regulation of cyclin E, cyclin D and cyclin B, CDK4 and CDK1. Further, SPAG9 gene silencing also resulted in reduction in cellular growth, and migration and invasion ability of cancer cells in vitro. CONCLUSIONS: Collectively, our data in clinical specimens indicated that SPAG9 is potential biomarker and therapeutic target for bladder TCC.

  16. Epithelial-Mesenchymal Transition in Non Small-cell Lung Cancer.

    Science.gov (United States)

    Tsoukalas, Nikolaos; Aravantinou-Fatorou, Eleni; Tolia, Maria; Giaginis, Constantinos; Galanopoulos, Michail; Kiakou, Maria; Kostakis, Ioannis D; Dana, Eugene; Vamvakaris, Ioannis; Korogiannos, Athanasios; Tsiambas, Evangelos; Salemis, Nikolaos; Kyrgias, George; Karameris, Andreas; Theocharis, Stamatios

    2017-04-01

    Lung cancer is the first cause of cancer related deaths in both males and females. Epithelial-mesenchymal transition (EMT) is a reversible process by which epithelial cells transform to mesenchymal stem cells by losing their cell polarity and cell-to-cell adhesion, gaining migratory and invasive properties. High levels of E-cadherin are expressed in epithelial cells, whereas mesenchymal cells express high levels of N-cadherin, fibronectin and vimentin. The aim of this study was to evaluate the correlation between E-cadherin and vimentin expression and their clinical significance in non-small cell lung cancer (NSCLC). The immunohistochemical expression of E-cadherin, vimentin and Ki-67 was performed on tissue microarrays from NSCLC specimens obtained from 112 newly- diagnosed cases and were studied using classical pathological evaluation. Associations between E-cadherin, vimentin and Ki-67 expression, clinicopathological variables and survival were analyzed. In all cases, a value of p≤0.05 was considered significant. Low E-cadherin expression was significantly correlated with tumor necrosis (p=0.019). Moreover, there was a trend for correlation between high E-cadherin expression and better overall survival (hazard ratio=1.02, and 95% confidence interval=0.45-1.87, p=0.091). There was also a significant negative correlation between vimentin expression and overall survival (hazard ratio=1.13, and 95% confidence interval=0.78-1.65, p=0.026). Additionally, there was a significant negative correlation between vimentin expression and grade I tumors (p=0.031). Finally, a positive correlation trend between vimentin expression and Ki-67 was found (p=0.073). High E-cadherin and low vimentin expression correlate with better prognosis and overall survival. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  17. Hemorrhagic shock-induced endothelial cell activation in a spontaneous breathing and a mechanical ventilation hemorrhagic shock model is induced by a proinflammatory response and not by hypoxia.

    Science.gov (United States)

    van Meurs, Matijs; Wulfert, Francis M; Jongman, Rianne M; Schipper, Martin; Houwertjes, Martin C; Vaneker, Michiel; Scheffer, Gert Jan; Teppema, Luc J; Aarts, Leon P H J; Heeringa, Peter; Zijlstra, Jan G; Molema, Grietje

    2011-09-01

    The interaction between neutrophils and activated endothelium is essential for the development of multiple organ dysfunction in patients with hemorrhagic shock (HS). Mechanical ventilation frequently is used in patients with HS. The authors sought to investigate the consequences of mechanical ventilation of mice subjected to HS on microvascular endothelial activation in the lung and kidney. Anesthetized wild type C57BL/6 male mice were subjected to controlled hemorrhage; subgroups of mice were mechanically ventilated during the HS insult. To study the effect of acute hypoxia on the mice, the animals were housed in hypoxic cages. Gene expression levels was assessed by quantitative real-time polymerase chain reaction. Protein expression was assessed by immunohistochemistry and enzyme-linked immunosorbent assay. Ninety minutes after the shock induction, a vascular bed-specific, heterogeneous proinflammatory endothelial activation represented by E-selectin, vascular cell adhesion molecule 1, and intercellular adhesion molecule 1 expression was seen in kidney and lung. No differences in adhesion molecules between the spontaneously breathing and mechanically ventilated mice were found. Concentrations of the proinflammatory cytokines chemokine (C-X-C motif) ligand 1 (11.0-fold) and interleukin-6 (21.7-fold) were increased after 90 min of HS. Two hours of 6% oxygen did not induce the expression of E-selectin, vascular cell adhesion molecule 1, and intercellular adhesion molecule 1 in the kidneys and the lung. Hemorrhagic shock leads to an early and reversible proinflammatory endothelial activation in kidney and lung. HS-induced endothelial activation is not changed by mechanical ventilation during the shock phase. Hypoxia alone does not lead to endothelial activation. The observed proinflammatory endothelial activation is mostly ischemia- or reperfusion-dependent and not related to hypoxia.

  18. Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Jin Young [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Hyoung Chul, E-mail: hcchoi@med.yu.ac.kr [Department of Pharmacology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of)

    2011-05-06

    Highlights: {yields} Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. {yields} Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. {yields} Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. {yields} Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. {yields} Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

  19. Aspirin-induced AMP-activated protein kinase activation regulates the proliferation of vascular smooth muscle cells from spontaneously hypertensive rats

    International Nuclear Information System (INIS)

    Sung, Jin Young; Choi, Hyoung Chul

    2011-01-01

    Highlights: → Aspirin-induced AMPK phosphorylation was greater in VSMC from SHR than WKY. → Aspirin-induced AMPK phosphorylation inhibited proliferation of VSMC from SHR. → Low basal AMPK phosphorylation in SHR elicits increased VSMC proliferation. → Inhibition of AMPK restored decreased VSMC proliferation by aspirin in SHR. → Aspirin exerts anti-proliferative effect through AMPK activation in VSMC from SHR. -- Abstract: Acetylsalicylic acid (aspirin), used to reduce risk of cardiovascular disease, plays an important role in the regulation of cellular proliferation. However, mechanisms responsible for aspirin-induced growth inhibition are not fully understood. Here, we investigated whether aspirin may exert therapeutic effects via AMP-activated protein kinase (AMPK) activation in vascular smooth muscle cells (VSMC) from wistar kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Aspirin increased AMPK and acetyl-CoA carboxylase phosphorylation in a time- and dose-dependent manner in VSMCs from WKY and SHR, but with greater efficacy in SHR. In SHR, a low basal phosphorylation status of AMPK resulted in increased VSMC proliferation and aspirin-induced AMPK phosphorylation inhibited proliferation of VSMCs. Compound C, an AMPK inhibitor, and AMPK siRNA reduced the aspirin-mediated inhibition of VSMC proliferation, this effect was more pronounced in SHR than in WKY. In VSMCs from SHR, aspirin increased p53 and p21 expression and inhibited the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. These results indicate that in SHR VSMCs aspirin exerts anti-proliferative effects through the induction of AMPK phosphorylation.

  20. Cystatin A suppresses tumor cell growth through inhibiting epithelial to mesenchymal transition in human lung cancer.

    Science.gov (United States)

    Ma, Yunxia; Chen, Yuan; Li, Yong; Grün, Katja; Berndt, Alexander; Zhou, Zhongwei; Petersen, Iver

    2018-03-06

    Cystatin A ( CSTA ), belonging to type 1 cystatin super-family, is expressed primarily in epithelial and lymphoid tissues for protecting cells from proteolysis of cytoplasmic and cytoskeletal proteins by cathepsins B, H and L. CSTA acts as a tumor suppressor in esophageal cancer, however, its role in lung cancer has not yet been elucidated. Here we found that CSTA was down-regulated in all lung cancer cell lines compared to normal lung epithelial cells. CSTA was restored in most lung cancer cell lines after treatment with demethylation agent 5-aza-2-deoxycytidine and deacetylation agent Trichostatin. Bisulfite sequencing revealed that CSTA was partially methylated in the promoter and exon 1. In primary lung tumors, squamous cell carcinoma (SCC) significantly expressed more CSTA compared to adenocarcinoma (pgrade (ptransition (MET) and prevented the TGF-β1-induced epithelial to mesenchymal transition (EMT) through inhibiting the ERK/MAPK pathway. In conclusion, our date indicate 1) epigenetic regulation is associated with CSTA gene silencing; 2) CSTA exerts tumor suppressive function through inhibiting MAPK and AKT pathways; 3) Overexpression of CSTA leads to MET and prevents TGF-β1-induced EMT by modulating the MAPK pathway; 4) CSTA may be a potential biomarker for lung SCC and tumor differentiation.

  1. Erk5 Is a Key Regulator of Naive-Primed Transition and Embryonic Stem Cell Identity

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    Charles A.C. Williams

    2016-08-01

    Full Text Available Embryonic stem cells (ESCs can self-renew or differentiate into any cell type, a phenomenon known as pluripotency. Distinct pluripotent states, termed naive and primed pluripotency, have been described. However, the mechanisms that control naive-primed pluripotent transition are poorly understood. Here, we perform a targeted screen for kinase inhibitors, which modulate the naive-primed pluripotent transition. We find that XMD compounds, which selectively inhibit Erk5 kinase and BET bromodomain family proteins, drive ESCs toward primed pluripotency. Using compound selectivity engineering and CRISPR/Cas9 genome editing, we reveal distinct functions for Erk5 and Brd4 in pluripotency regulation. We show that Erk5 signaling maintains ESCs in the naive state and suppresses progression toward primed pluripotency and neuroectoderm differentiation. Additionally, we identify a specialized role for Erk5 in defining ESC lineage selection, whereby Erk5 inhibits a cardiomyocyte-specific differentiation program. Our data therefore reveal multiple critical functions for Erk5 in controlling ESC identity.

  2. Experience of combined cisplatin and radiation therapy for advanced urinary tract transitional cell carcinoma

    International Nuclear Information System (INIS)

    Yoshioka, Toshiaki; Utsunomiya, Masato; Itoh, Hiroshi; Itatani, Hiroaki; Namiki, Mikio.

    1987-01-01

    Since March, 1981, 13 patients with locally advanced transitional cell carcinoma were treated by combined cisdiamminedichloroplatinum (cisplatin) and full dose radiotherapy. They were 10 men and 3 women. The patient ages ranged from 42 to 79 years, with a median of 59.5 years. The primary sites of transitional cell carcinoma were bladder in 5, ureter in 6, renal pelvis in 1 and prostate in 1. Radiotherapy consisted of a mean tumor dose of 48.7 gray, with a range of 40 to 66.4 gray, was administered with cobalt 60. Cisplatin was infused 5 days a week with a daily dose of 20 to 30 mg. 4 patients recieved 2 courses of cisplatin infusion and others 1 or less. Of the 4 evaluable patients 3 (75 %) achieved a complete response. Toxicity was evaluated for the 13 patients. Mainly gastrointestinal toxicity was noted: appetite loss in 9 (69.2 %), nausea and/or vomiting in 5 (38.5 %) and diarrhea in 5 (38.5 %). Leukocytopenia was noted in 7 patients (53.9 %), but in no one leukocyte count was less than 2000/mm 3 . Mild thrombocytopenia was noted only in 3 patients (23.1 %). All of these toxicities were mild, and the patients recovered soon after the therapy. Herein it is discussed about future problems such as solution of interaction mechanism, detection of practical dose and administering method of cisplatin and radiation. (author)

  3. Mesothelin promotes epithelial-to-mesenchymal transition and tumorigenicity of human lung cancer and mesothelioma cells.

    Science.gov (United States)

    He, Xiaoqing; Wang, Liying; Riedel, Heimo; Wang, Kai; Yang, Yong; Dinu, Cerasela Zoica; Rojanasakul, Yon

    2017-03-14

    Lung cancer and pleural mesothelioma are two of the most deadly forms of cancer. The prognosis of lung cancer and mesothelioma is extremely poor due to limited treatment modalities and lack of understanding of the disease mechanisms. We have identified mesothelin as a potentially unique therapeutic target that as a specific advantage appears nonessential in most cell types. Mesothelin (MSLN), a plasma membrane differentiation antigen, is expressed at a high level in many human solid tumors, including 70% of lung cancer and nearly all mesotheliomas. However, the role of MSLN in the disease process and underlying mechanisms is largely unknown. ShRNA knockdown and overexpression of MSLN were performed in human cancer cell lines and corresponding normal cells, respectively. Tumorigenic and metastatic effects of MSLN were examined by tumor sphere formation, migration, and invasion assays in vitro, as well as xenograft tumor assay in vivo. EMT and CSCs were detected by qPCR array, immunoblotting and flow cytometry. MSLN plays a key role in controlling epithelial-to-mesenchymal transition (EMT) and stem properties of human lung cancer and mesothelioma cells that control their tumorigenicity and metastatic potential. Firstly, MSLN was found to be highly upregulated in non-small cell lung cancer (NSCLC) patient tissues and in lung carcinoma and mesothelioma cell lines. Secondly, genetic knockdown of MSLN significantly reduced anchorage-independent cell growth, tumor sphere formation, cell adhesion, migration and invasion in vitro, as well as tumor formation and metastasis in vivo. Thirdly, ectopic overexpression of MSLN induced the malignant phenotype of non-cancerous cells, supporting its role as an oncogene. Finally, mechanistic studies revealed that knockdown of MSLN reversed EMT and attenuated stem cell properties, in addition to inhibiting tumor growth and metastasis. These results indicate an essential role of MSLN in controlling EMT and stem cell properties of human

  4. Staphylococcus-mediated T-cell activation and spontaneous natural killer cell activity in the absence of major histocompatibility complex class II molecules

    Science.gov (United States)

    Chapes, S. K.; Hoynowski, S. M.; Woods, K. M.; Armstrong, J. W.; Beharka, A. A.; Iandolo, J. J.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    We used major histocompatibility complex class II antigen-deficient transgenic mice to show that in vitro natural killer cell cytotoxicity and T-cell activation by staphylococcal exotoxins (superantigens) are not dependent upon the presence of major histocompatibility complex class II molecules. T cells can be activated by exotoxins in the presence of exogenously added interleukin 1 or 2 or in the presence of specific antibody without exogenously added cytokines.

  5. Before the endless forms: embodied model of transition from single cells to aggregates to ecosystem engineering.

    Directory of Open Access Journals (Sweden)

    Ricard V Solé

    Full Text Available The emergence of complex multicellular systems and their associated developmental programs is one of the major problems of evolutionary biology. The advantages of cooperation over individuality seem well known but it is not clear yet how such increase of complexity emerged from unicellular life forms. Current multicellular systems display a complex cell-cell communication machinery, often tied to large-scale controls of body size or tissue homeostasis. Some unicellular life forms are simpler and involve groups of cells cooperating in a tissue-like fashion, as it occurs with biofilms. However, before true gene regulatory interactions were widespread and allowed for controlled changes in cell phenotypes, simple cellular colonies displaying adhesion and interacting with their environments were in place. In this context, models often ignore the physical embedding of evolving cells, thus leaving aside a key component. The potential for evolving pre-developmental patterns is a relevant issue: how far a colony of evolving cells can go? Here we study these pre-conditions for morphogenesis by using CHIMERA, a physically embodied computational model of evolving virtual organisms in a pre-Mendelian world. Starting from a population of identical, independent cells moving in a fluid, the system undergoes a series of changes, from spatial segregation, increased adhesion and the development of generalism. Eventually, a major transition occurs where a change in the flow of nutrients is triggered by a sub-population. This ecosystem engineering phenomenon leads to a subsequent separation of the ecological network into two well defined compartments. The relevance of these results for evodevo and its potential ecological triggers is discussed.

  6. Snail1 induces epithelial-to-mesenchymal transition and tumor initiating stem cell characteristics

    International Nuclear Information System (INIS)

    Dang, Hien; Ding, Wei; Emerson, Dow; Rountree, C Bart

    2011-01-01

    Tumor initiating stem-like cells (TISCs) are a subset of neoplastic cells that possess distinct survival mechanisms and self-renewal characteristics crucial for tumor maintenance and propagation. The induction of epithelial-mesenchymal-transition (EMT) by TGFβ has been recently linked to the acquisition of TISC characteristics in breast cancer. In HCC, a TISC and EMT phenotype correlates with a worse prognosis. In this work, our aim is to elucidate the underlying mechanism by which cells acquire tumor initiating characteristics after EMT. Gene and protein expression assays and Nanog-promoter luciferase reporter were utilized in epithelial and mesenchymal phenotype liver cancer cell lines. EMT was analyzed with migration/invasion assays. TISC characteristics were analyzed with tumor-sphere self-renewal and chemotherapy resistance assays. In vivo tumor assay was performed to investigate the role of Snail1 in tumor initiation. TGFβ induced EMT in epithelial cells through the up-regulation of Snail1 in Smad-dependent signaling. Mesenchymal liver cancer post-EMT demonstrates TISC characteristics such as tumor-sphere formation but are not resistant to cytotoxic therapy. The inhibition of Snail1 in mesenchymal cells results in decreased Nanog promoter luciferase activity and loss of self-renewal characteristics in vitro. These changes confirm the direct role of Snail1 in some TISC traits. In vivo, the down-regulation of Snail1 reduced tumor growth but was not sufficient to eliminate tumor initiation. In summary, TGFβ induces EMT and TISC characteristics through Snail1 and Nanog up-regulation. In mesenchymal cells post-EMT, Snail1 directly regulates Nanog expression, and loss of Snail1 regulates tumor growth without affecting tumor initiation

  7. Induction of epithelial-mesenchymal transition (EMT) in breast cancer cells is calcium signal dependent.

    Science.gov (United States)

    Davis, F M; Azimi, I; Faville, R A; Peters, A A; Jalink, K; Putney, J W; Goodhill, G J; Thompson, E W; Roberts-Thomson, S J; Monteith, G R

    2014-05-01

    Signals from the tumor microenvironment trigger cancer cells to adopt an invasive phenotype through epithelial-mesenchymal transition (EMT). Relatively little is known regarding key signal transduction pathways that serve as cytosolic bridges between cell surface receptors and nuclear transcription factors to induce EMT. A better understanding of these early EMT events may identify potential targets for the control of metastasis. One rapid intracellular signaling pathway that has not yet been explored during EMT induction is calcium. Here we show that stimuli used to induce EMT produce a transient increase in cytosolic calcium levels in human breast cancer cells. Attenuation of the calcium signal by intracellular calcium chelation significantly reduced epidermal growth factor (EGF)- and hypoxia-induced EMT. Intracellular calcium chelation also inhibited EGF-induced activation of signal transducer and activator of transcription 3 (STAT3), while preserving other signal transduction pathways such as Akt and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. To identify calcium-permeable channels that may regulate EMT induction in breast cancer cells, we performed a targeted siRNA-based screen. We found that transient receptor potential-melastatin-like 7 (TRPM7) channel expression regulated EGF-induced STAT3 phosphorylation and expression of the EMT marker vimentin. Although intracellular calcium chelation almost completely blocked the induction of many EMT markers, including vimentin, Twist and N-cadherin, the effect of TRPM7 silencing was specific for vimentin protein expression and STAT3 phosphorylation. These results indicate that TRPM7 is a partial regulator of EMT in breast cancer cells, and that other calcium-permeable ion channels are also involved in calcium-dependent EMT induction. In summary, this work establishes an important role for the intracellular calcium signal in the induction of EMT in human breast cancer cells. Manipulation of

  8. Live cell plasma membranes do not exhibit a miscibility phase transition over a wide range of temperatures.

    Science.gov (United States)

    Lee, Il-Hyung; Saha, Suvrajit; Polley, Anirban; Huang, Hector; Mayor, Satyajit; Rao, Madan; Groves, Jay T

    2015-03-26

    Lipid/cholesterol mixtures derived from cell membranes as well as their synthetic reconstitutions exhibit well-defined miscibility phase transitions and critical phenomena near physiological temperatures. This suggests that lipid/cholesterol-mediated phase separation plays a role in the organization of live cell membranes. However, macroscopic lipid-phase separation is not generally observed in cell membranes, and the degree to which properties of isolated lipid mixtures are preserved in the cell membrane remain unknown. A fundamental property of phase transitions is that the variation of tagged particle diffusion with temperature exhibits an abrupt change as the system passes through the transition, even when the two phases are distributed in a nanometer-scale emulsion. We support this using a variety of Monte Carlo and atomistic simulations on model lipid membrane systems. However, temperature-dependent fluorescence correlation spectroscopy of labeled lipids and membrane-anchored proteins in live cell membranes shows a consistently smooth increase in the diffusion coefficient as a function of temperature. We find no evidence of a discrete miscibility phase transition throughout a wide range of temperatures: 14-37 °C. This contrasts the behavior of giant plasma membrane vesicles (GPMVs) blebbed from the same cells, which do exhibit phase transitions and macroscopic phase separation. Fluorescence lifetime analysis of a DiI probe in both cases reveals a significant environmental difference between the live cell and the GPMV. Taken together, these data suggest the live cell membrane may avoid the miscibility phase transition inherent to its lipid constituents by actively regulating physical parameters, such as tension, in the membrane.

  9. A Cbx8-containing polycomb complex facilitates the transition to gene activation during ES cell differentiation.

    Directory of Open Access Journals (Sweden)

    Catherine Creppe

    2014-12-01

    Full Text Available Polycomb proteins play an essential role in maintaining the repression of developmental genes in self-renewing embryonic stem cells. The exact mechanism allowing the derepression of polycomb target genes during cell differentiation remains unclear. Our project aimed to identify Cbx8 binding sites in differentiating mouse embryonic stem cells. Therefore, we used a genome-wide chromatin immunoprecipitation of endogenous Cbx8 coupled to direct massive parallel sequencing (ChIP-Seq. Our analysis identified 171 high confidence peaks. By crossing our data with previously published microarray analysis, we show that several differentiation genes transiently recruit Cbx8 during their early activation. Depletion of Cbx8 partially impairs the transcriptional activation of these genes. Both interaction analysis, as well as chromatin immunoprecipitation experiments support the idea that activating Cbx8 acts in the context of an intact PRC1 complex. Prolonged gene activation results in eviction of PRC1 despite persisting H3K27me3 and H2A ubiquitination. The composition of PRC1 is highly modular and changes when embryonic stem cells commit to differentiation. We further demonstrate that the exchange of Cbx7 for Cbx8 is required for the effective activation of differentiation genes. Taken together, our results establish a function for a Cbx8-containing complex in facilitating the transition from a Polycomb-repressed chromatin state to an active state. As this affects several key regulatory differentiation genes this mechanism is likely to contribute to the robust execution of differentiation programs.

  10. Metabolic re-wiring of isogenic breast epithelial cell lines following epithelial to mesenchymal transition.

    Science.gov (United States)

    Halldorsson, Skarphedinn; Rohatgi, Neha; Magnusdottir, Manuela; Choudhary, Kumari Sonal; Gudjonsson, Thorarinn; Knutsen, Erik; Barkovskaya, Anna; Hilmarsdottir, Bylgja; Perander, Maria; Mælandsmo, Gunhild M; Gudmundsson, Steinn; Rolfsson, Óttar

    2017-06-28

    Epithelial to mesenchymal transition (EMT) has implications in tumor progression and metastasis. Metabolic alterations have been described in cancer development but studies focused on the metabolic re-wiring that takes place during EMT are still limited. We performed metabolomics profiling of a breast epithelial cell line and its EMT derived mesenchymal phenotype to create genome-scale metabolic models descriptive of both cell lines. Glycolysis and OXPHOS were higher in the epithelial phenotype while amino acid anaplerosis and fatty acid oxidation fueled the mesenchymal phenotype. Through comparative bioinformatics analysis, PPAR-γ1, PPAR- γ2 and AP-1 were found to be the most influential transcription factors associated with metabolic re-wiring. In silico gene essentiality analysis predicts that the LAT1 neutral amino acid transporter is essential for mesenchymal cell survival. Our results define metabolic traits that distinguish an EMT derived mesenchymal cell line from its epithelial progenitor and may have implications in cancer progression and metastasis. Furthermore, the tools presented here can aid in identifying critical metabolic nodes that may serve as therapeutic targets aiming to prevent EMT and inhibit metastatic dissemination. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  11. Suppressor of fused (Sufu) promotes epithelial-mesenchymal transition (EMT) in cervical squamous cell carcinoma

    Science.gov (United States)

    Zhang, Ziyu; Zou, Yang; Liang, Meirong; Chen, Yuanting; Luo, Yong; Yang, Bicheng; Liu, Faying; Qin, Yunna; He, Deming; Wang, Feng; Huang, Ouping

    2017-01-01

    Suppressor of fused is essential for the maximal activation of Sonic Hedgehog signaling in development and tumorigenesis. However, the role of Sufu in cervical carcinoma remains unknown. Here, we report new findings of Sufu in regulating the epithelial-to-mesenchymal transition through the FoxM1 transcriptional modulation by 14-3-3ζ protein in cervical carcinoma. Sufu is overexpressed in cervical squamous cell carcinoma and its level in clinical tumor tissues is positively correlated with 14-3-3ζ. Functionanlly, siSufu remarkably prevents the cancer cell migration and invasion. We further demonstrate that the transcriptional activity of Sufu is increased by FoxM1, of which stability is promoted by 14-3-3ζ. Knockdown FoxM1 decreases the invasion of SiHa cells and reconstitution of Sufu rescues the invasion of these cells.Finally, overexpression of Sufu is significantly associated with differentiation grade, FIGO stage, Depth of stromal invasion and vascular cancer embolus. Our findings highlight a novel role for Sufu in cervical carcinogenesis. PMID:29371981

  12. MAEL expression links epithelial-mesenchymal transition and stem cell properties in colorectal cancer.

    Science.gov (United States)

    Li, Qingguo; Wei, Ping; Huang, Ben; Xu, Ye; Li, Xinxiang; Li, Yaqi; Cai, Sanjun; Li, Dawei

    2016-12-01

    MAEL plays a central role during spermatogenesis by repressing transposable elements and preventing their mobilisation, however, its role on cancers is unclear. In this study, MAEL expression was analysed in a tissue microarray containing 185 samples of primary colon cancer tumor samples and human colon cancer cell lines. The effect of MAEL on cell proliferation, tumorigenesis, metastasis and drug resistance was examined in vitro and in vivo. Immunoprecipitation assay, confocal immunofluorescent analysis and luciferase assay were used for mechanism study. As results, MAEL was significantly upregulated in colon cancer patient tissue samples, and elevated MAEL protein levels positively correlated with overall survival and disease free survival of colon cancer patients. Using in vitro and in vivo models, we demonstrated that MAEL expression was correlated with cell proliferation, invasion and drug resistance of colon cancer cells by inducing epithelial-mesenchymal transition and stemness characteristics. Mechanistically, our study demonstrated that MAEL interacts with Snail and inhibit E-cadherin promoter activity. Collectively, MAEL is an oncogene that plays an important role in the development and progression of colon cancer, which may be a novel potential therapeutic target for colon cancer. © 2016 UICC.

  13. Renal Cell Carcinoma of the Kidney with Synchronous Ipsilateral Transitional Cell Carcinoma of the Renal Pelvis

    Directory of Open Access Journals (Sweden)

    Dogan Atilgan

    2013-01-01

    Full Text Available A 73-year-old man was admitted to our clinic with flank pain and gross macroscopic hematuria. Radiologic examination revealed a solid mass in the left kidney and additionally another mass in the ureteropelvic junction of the same kidney with severe hydronephrosis. Left nephroureterectomy with bladder cuff removel was performed, and histopathological evolution showed a Fuhrman grade 3 clear cell type RCC with low-grade TCC of the pelvis.

  14. Genome-wide analysis of the maternal-to-zygotic transition in Drosophila primordial germ cells

    Science.gov (United States)

    2012-01-01

    Background During the maternal-to-zygotic transition (MZT) vast changes in the embryonic transcriptome are produced by a combination of two processes: elimination of maternally provided mRNAs and synthesis of new transcripts from the zygotic genome. Previous genome-wide analyses of the MZT have been restricted to whole embryos. Here we report the first such analysis for primordial germ cells (PGCs), the progenitors of the germ-line stem cells. Results We purified PGCs from Drosophila embryos, defined their proteome and transcriptome, and assessed the content, scale and dynamics of their MZT. Transcripts encoding proteins that implement particular types of biological functions group into nine distinct expression profiles, reflecting coordinate control at the transcriptional and posttranscriptional levels. mRNAs encoding germ-plasm components and cell-cell signaling molecules are rapidly degraded while new transcription produces mRNAs encoding the core transcriptional and protein synthetic machineries. The RNA-binding protein Smaug is essential for the PGC MZT, clearing transcripts encoding proteins that regulate stem cell behavior, transcriptional and posttranscriptional processes. Computational analyses suggest that Smaug and AU-rich element binding proteins function independently to control transcript elimination. Conclusions The scale of the MZT is similar in the soma and PGCs. However, the timing and content of their MZTs differ, reflecting the distinct developmental imperatives of these cell types. The PGC MZT is delayed relative to that in the soma, likely because relief of PGC-specific transcriptional silencing is required for zygotic genome activation as well as for efficient maternal transcript clearance. PMID:22348290

  15. Inactivation of Bacillus cereus vegetative cells by gastric acid and bile during in vitro gastrointestinal transit

    Directory of Open Access Journals (Sweden)

    Ceuppens Siele

    2012-10-01

    Full Text Available Abstract Background The foodborne pathogen Bacillus cereus can cause diarrhoeal food poisoning by production of enterotoxins in the small intestine. The prerequisite for diarrhoeal disease is thus survival during gastrointestinal passage. Methods Vegetative cells of 3 different B. cereus strains were cultivated in a real composite food matrix, lasagne verde, and their survival during subsequent simulation of gastrointestinal passage was assessed using in vitro experiments simulating transit through the human upper gastrointestinal tract (from mouth to small intestine. Results No survival of vegetative cells was observed, despite the high inoculum levels of 7.0 to 8.0 log CFU/g and the presence of various potentially protective food components. Significant fractions (approx. 10% of the consumed inoculum of B. cereus vegetative cells survived gastric passage, but they were subsequently inactivated by bile exposure in weakly acidic intestinal medium (pH 5.0. In contrast, the low numbers of spores present (up to 4.0 log spores/g showed excellent survival and remained viable spores throughout the gastrointestinal passage simulation. Conclusion Vegetative cells are inactivated by gastric acid and bile during gastrointestinal passage, while spores are resistant and survive. Therefore, the physiological form (vegetative cells or spores of the B. cereus consumed determines the subsequent gastrointestinal survival and thus the infective dose, which is expected to be much lower for spores than vegetative cells. No significant differences in gastrointestinal survival ability was found among the different strains. However, considerable strain variability was observed in sporulation tendency during growth in laboratory medium and food, which has important implications for the gastrointestinal survival potential of the different B. cereus strains.

  16. Fourier transform infra-red spectroscopic signatures for lung cells' epithelial mesenchymal transition: A preliminary report

    Science.gov (United States)

    Sarkar, Atasi; Sengupta, Sanghamitra; Mukherjee, Anirban; Chatterjee, Jyotirmoy

    2017-02-01

    Infra red (IR) spectral characterization can provide label-free cellular metabolic signatures of normal and diseased circumstances in a rapid and non-invasive manner. Present study endeavoured to enlist Fourier transform infra red (FTIR) spectroscopic signatures for lung normal and cancer cells during chemically induced epithelial mesenchymal transition (EMT) for which global metabolic dimension is not well reported yet. Occurrence of EMT was validated with morphological and immunocytochemical confirmation. Pre-processed spectral data was analyzed using ANOVA and principal component analysis-linear discriminant analysis (PCA-LDA). Significant differences observed in peak area corresponding to biochemical fingerprint (900-1800 cm- 1) and high wave-number (2800-3800 cm- 1) regions contributed to adequate PCA-LDA segregation of cells undergoing EMT. The findings were validated by re-analysis of data using another in-house built binary classifier namely vector valued regularized kernel approximation (VVRKFA), in order to understand EMT progression. To improve the classification accuracy, forward feature selection (FFS) tool was employed in extracting potent spectral signatures by eliminating undesirable noise. Gradual increase in classification accuracy with EMT progression of both cell types indicated prominence of the biochemical alterations. Rapid changes in cellular metabolome noted in cancer cells within first 24 h of EMT induction along with higher classification accuracy for cancer cell groups in comparison to normal cells might be attributed to inherent differences between them. Spectral features were suggestive of EMT triggered changes in nucleic acid, protein, lipid and bound water contents which can emerge as the useful markers to capture EMT related cellular characteristics.

  17. Activation-induced cytidine deaminase (AID) is necessary for the epithelial–mesenchymal transition in mammary epithelial cells

    OpenAIRE

    Muñoz, Denise P.; Lee, Elbert L.; Takayama, Sachiko; Coppé, Jean-Philippe; Heo, Seok-Jin; Boffelli, Dario; Di Noia, Javier M.; Martin, David I. K.

    2013-01-01

    The epithelial to mesenchymal transition (EMT) is a driving force behind normal morphogenesis and tumor metastasis. We have found evidence that the EMT in both malignant and nonmalignant mammary epithelial cells requires the enzyme activation-induced cytidine deaminase (AID). AID is induced in mammary epithelial cell lines by inflammatory stimuli that also induce the EMT. Deficiency of AID in these cells blocks morphological and transcriptional changes typical of the EMT and increases promote...

  18. Mast cells induce epithelial-to-mesenchymal transition and stem cell features in human thyroid cancer cells through an IL-8-Akt-Slug pathway.

    Science.gov (United States)

    Visciano, C; Liotti, F; Prevete, N; Cali', G; Franco, R; Collina, F; de Paulis, A; Marone, G; Santoro, M; Melillo, R M

    2015-10-01

    There is increasing evidence that mast cells (MCs) and their mediators are involved in the remodeling of the tumor microenvironment and promote tumor growth, angiogenesis and metastasis. We have found that an increased density of MCs in thyroid cancer (TC) correlates with enhanced invasiveness. However, the MC-derived factors responsible for this activity and the mechanisms by which they enhance TC invasiveness remain unidentified. Here, we report that MCs, when activated by TC cells, produce soluble factors that induce epithelial-to-mesenchymal transition (EMT) and stemness features of TC cells. We identified CXCL8/interleukin (IL)-8 as the main mediator contained in activated MC conditioned media (CM) capable of inducing both EMT and stemness of TC cells. Mechanistically, MC CM or exogenous IL-8 stimulated Akt phosphorylation and Slug expression in TC cells. The inhibition of the Akt pathway or depletion of the Slug transcription factor by RNA interference, reverted EMT and stemness responses. TC cells stably transfected with exogenous IL-8 underwent EMT, displayed increased stemness and enhanced tumorigenicity with respect to control cells. The analysis of TC surgical specimens by immunohistochemical analysis demonstrated a positive correlation between MC density (Tryptase(+) cells) and stemness features (OCT4 staining). Taken together, our data identify an MC-dependent IL-8-Akt-Slug pathway that sustains EMT/stemness of TC cells. The blockade of this circuit might be exploited for the therapy of advanced TC.

  19. Fuzheng Huayu Recipe Ameliorates Liver Fibrosis by Restoring Balance between Epithelial-to-Mesenchymal Transition and Mesenchymal-to-Epithelial Transition in Hepatic Stellate Cells

    Directory of Open Access Journals (Sweden)

    Qin Pan

    2015-01-01

    Full Text Available Activation of hepatic stellate cells (HSCs depending on epithelial-to-mesenchymal transition (EMT reflects the key event of liver fibrosis. Contrastively, mesenchymal-to-epithelial transition (MET of HSCs facilitates the fibrosis resolution. Here we investigated the effect of Fuzheng Huayu (FZHY recipe, a Chinese herbal decoction made of Radix Salviae Miltiorrhizae, Semen Persicae, Cordyceps sinensis, Pollen Pini, and Gynostemma pentaphyllum, on liver fibrosis concerning the balance of EMT and MET in HSCs. In contrast to the increased TGF-β1/BMP-7 ratio in activated HSCs, FZHY administration induced significant upregulation of BMP-7 and downregulation of TGF-β1 at both transcription and translation levels. Restoration of TGF-β1/BMP-7 ratio inhibited the expression of p38 MAPK and phosphorylated p38 MAPK, resulting in the reversal of epithelial-to-mesenchymal transition (EMT to mesenchymal-to-epithelial transition (MET as characterized by the abolishment of EMT markers (α-SMA and desmin and reoccurrence of MET marker (E-cadherin. In vivo treatment of FZHY recipe also demonstrated the statistical reduction of activated HSCs with EMT phenotype, which attenuated the carbon tetrachloride- (CCl4- induced liver fibrosis in a dose-dependent manner. These findings may highlight a novel antifibrotic role of FZHY recipe on the basis of rebalancing EMT and MET in HSCs.

  20. Self-efficacy, transition, and patient outcomes in the sickle cell disease population.

    Science.gov (United States)

    Molter, Brittany L; Abrahamson, Kathleen

    2015-06-01

    Severe pain is a common symptom of sickle cell disease (SCD). Transitions between adult and pediatric care are a point of particular vulnerability for patients, increasing the risk for poor pain management. The purpose of this literature review was to investigate the relationships among self-efficacy, transition, and SCD health outcomes. A systematic literature search was performed within CINAHL, Academic Search Premier, MEDLINE, and PubMed on published papers between 2003 and 2013. After applying exclusion criteria, 20 articles were used in the final review. Few studies were identified that directly tested the relationship between self-efficacy and SCD outcomes. Although there are few studies on this topic, most demonstrated positive correlations between self-efficacy during transition and positive patient outcomes in the SCD population. Additional studies are needed to support causation. Studies were commonly limited by small sample sizes and attrition. Furthermore, there is a large gap in the literature regarding how self-efficacy can be increased in these patients. Interventions that promote self-efficacy have the potential to improve SCD pain outcomes, but more research is needed to develop interventions to increase these adolescents' self-efficacy. If providers can identify individuals in this population with low self-efficacy, they may be able to intervene early to improve patient outcomes. Most identified studies point to the positive correlation between self-efficacy and positive health outcomes in adolescents with SCD. Self-efficacy has the potential to guide self-care interventions and further research with the SCD population. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  1. Electrospinning of PVA/sericin nanofiber and the effect on epithelial-mesenchymal transition of A549 cells.

    Science.gov (United States)

    Yan, Shanshan; Li, Xiuchun; Dai, Jing; Wang, Yiqun; Wang, Binbin; Lu, Yi; Shi, Jianlin; Huang, Pengyu; Gong, Jinkang; Yao, Yuan

    2017-10-01

    This research aims to investigate the cell-nanomaterial interaction between epithelial-mesenchymal transition of A549 cell and electrospinning nanofibers composed of polyvinyl alcohol (PVA)/silk sericin (SS). The electrospinning of regenerated nanofiber was performed with water as a spinning solvent and glutaraldehyde as a chemical cross-linker. Solution concentration, applied voltage and spin distances as well as other parameters were optimized to generate fine nanofibers with smooth surface in good homogeneity. From the scanning electron microscopy (SEM) analysis, the nanofibers had an average diameter of 200nm. Epithelial-mesenchymal transition (EMT) is a process by which epithelial cells lose their cell polarity to become mesenchymal stem cells. This transition is affected by multiple biochemical and physical factors in cell metabolism cascade. Herein, we investigate the biophysical effect on A549 EMT by culturing cells on nanofibrous mats with different topography and composition. The cell viability was evaluated by biochemical assay and its morphology was observed with SEM. The results demonstrate that cells appropriately attached to the surface of the nanofibrous mats with extended morphology by their filopodia. Gene expression analysis was conducted by real-time PCR using multiple markers for detecting EMT: N-cadherin (NCad), Vimentin (Vim), Fibronectin (Fib) and Matrix metallopeptidase (MMP9). An increasing expression pattern was observed on NCad, Vim, Fib, with respect to a negative control as cell cultured on polystyrene dish. This result indicates the 200nm PVA/SS nanofibers may induce A549 cells to process epithelial-mesenchymal transition during the culturing. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Role of mitochondrial permeability transition in human renal tubular epithelial cell death induced by aristolochic acid

    International Nuclear Information System (INIS)

    Qi Xinming; Cai Yan; Gong Likun; Liu Linlin; Chen Fangping; Xiao Ying; Wu Xiongfei; Li Yan; Xue Xiang; Ren Jin

    2007-01-01

    Aristolochic acid (AA), a natural nephrotoxin and carcinogen, can induce a progressive tubulointerstitial nephropathy. However, the mechanism by which AA causes renal injury remains largely unknown. Here we reported that the mitochondrial permeability transition (MPT) plays an important role in the renal injury induced by aristolochic acid I (AAI). We found that in the presence of Ca 2+ , AAI caused mitochondrial swelling, leakage of Ca 2+ , membrane depolarization, and release of cytochrome c in isolated kidney mitochondria. These alterations were suppressed by cyclosporin A (CsA), an agent known to inhibit MPT. Culture of HK-2 cell, a human renal tubular epithelial cell line for 24 h with AAI caused a decrease in cellular ATP, mitochondrial membrane depolarization, cytochrome c release, and increase of caspase 3 activity. These toxic effects of AAI were attenuated by CsA and bongkrekic acid (BA), another specific MPT inhibitor. Furthermore, AAI greatly inhibited the activity of mitochondrial adenine nucleotide translocator (ANT) in isolated mitochondria. We suggested that ANT may mediate, at least in part, the AAI-induced MPT. Taken together, these results suggested that MPT plays a critical role in the pathogenesis of HK-2 cell injury induced by AAI and implied that MPT might contribute to human nephrotoxicity of aristolochic acid

  3. MUC1 enhances invasiveness of pancreatic cancer cells by inducing epithelial to mesenchymal transition.

    Science.gov (United States)

    Roy, L D; Sahraei, M; Subramani, D B; Besmer, D; Nath, S; Tinder, T L; Bajaj, E; Shanmugam, K; Lee, Y Y; Hwang, S I L; Gendler, S J; Mukherjee, P

    2011-03-24

    Increased motility and invasiveness of pancreatic cancer cells are associated with epithelial to mesenchymal transition (EMT). Snai1 and Slug are zinc-finger transcription factors that trigger this process by repressing E-cadherin and enhancing vimentin and N-cadherin protein expression. However, the mechanisms that regulate this activation in pancreatic tumors remain elusive. MUC1, a transmembrane mucin glycoprotein, is associated with the most invasive forms of pancreatic ductal adenocarcinomas (PDA). In this study, we show that over expression of MUC1 in pancreatic cancer cells triggers the molecular process of EMT, which translates to increased invasiveness and metastasis. EMT was significantly reduced when MUC1 was genetically deleted in a mouse model of PDA or when all seven tyrosines in the cytoplasmic tail of MUC1 were mutated to phenylalanine (mutated MUC1 CT). Using proteomics, RT-PCR and western blotting, we revealed a significant increase in vimentin, Slug and Snail expression with repression of E-Cadherin in MUC1-expressing cells compared with cells expressing the mutated MUC1 CT. In the cells that carried the mutated MUC1 CT, MUC1 failed to co-immunoprecipitate with β-catenin and translocate to the nucleus, thereby blocking transcription of the genes associated with EMT and metastasis. Thus, functional tyrosines are critical in stimulating the interactions between MUC1 and β-catenin and their nuclear translocation to initiate the process of EMT. This study signifies the oncogenic role of MUC1 CT and is the first to identify a direct role of the MUC1 in initiating EMT during pancreatic cancer. The data may have implications in future design of MUC1-targeted therapies for pancreatic cancer.

  4. High glucose induced endothelial to mesenchymal transition in human umbilical vein endothelial cell.

    Science.gov (United States)

    Yu, Chun-Hong; Suriguga; Gong, Meng; Liu, Wen-Juan; Cui, Ning-Xuan; Wang, Ying; Du, Xin; Yi, Zong-Chun

    2017-06-01

    Studies have shown that endothelial-to-mesenchymal transition (EndMT) could contribute to the progression of diabetic nephropathy, diabetic renal fibrosis, and cardiac fibrosis. The aim of this study was to investigate the influence of high glucose and related mechanism of MAPK inhibitor or specific antioxidant on the EndMT. In vitro human umbilical vein endothelial cells (HUVEC) were cultured with 11mM, 30mM, 60mM and 120mM glucose for 0, 24, 48, 72 and 168h. Endothelial cell morphology was observed with microscope, and RT-PCR was used to detect mRNA expression of endothelial markers VE-cadherin and CD31, mesenchymal markers α-SMA and collagen I, and transforming growth factor TGF-β1. Immunofluorescence staining was performed to detect the expression of CD31 and α-SMA. The concentration of TGF-β1 in the supernatant was detected by ELISA. ERK1/2 phosphorylation level was detected by Western blot analysis. High glucose induced EndMT and increased the TGF-β1 level in HUVEC cells. Cells in high glucose for 7 days showed a significant decrease in mRNA expression of CD31 and VE-cadherin, and a significant increase in that of α-SMA and collagen I, while lost CD31 staining and acquired α-SMA staining. ERK signaling pathway blocker PD98059 significantly attenuated the high glucose-induced increase in the ERK1/2 phosphorylation level. PD98059 and NAC both inhibited high glucose-induced TGF-β1 expression and attenuated EndMT marker protein synthesis. High glucose could induce HUVEC cells to undergo EndMT. NAC and ERK signaling pathway may play important role in the regulation of the TGF-β1 biosynthesis during high glucose-induced EndMT. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. The TCP4 transcription factor of Arabidopsis blocks cell division in yeast at G1 → S transition

    International Nuclear Information System (INIS)

    Aggarwal, Pooja; Padmanabhan, Bhavna; Bhat, Abhay; Sarvepalli, Kavitha; Sadhale, Parag P.; Nath, Utpal

    2011-01-01

    Highlights: → TCP4 is a class II TCP transcription factor, that represses cell division in Arabidopsis. → TCP4 expression in yeast retards cell division by blocking G1 → S transition. → Genome-wide expression studies and Western analysis reveals stabilization of cell cycle inhibitor Sic1, as possible mechanism. -- Abstract: The TCP transcription factors control important aspects of plant development. Members of class I TCP proteins promote cell cycle by regulating genes directly involved in cell proliferation. In contrast, members of class II TCP proteins repress cell division. While it has been postulated that class II proteins induce differentiation signal, their exact role on cell cycle has not been studied. Here, we report that TCP4, a class II TCP protein from Arabidopsis that repress cell proliferation in developing leaves, inhibits cell division by blocking G1 → S transition in budding yeast. Cells expressing TCP4 protein with increased transcriptional activity fail to progress beyond G1 phase. By analyzing global transcriptional status of these cells, we show that expression of a number of cell cycle genes is altered. The possible mechanism of G1 → S arrest is discussed.

  6. HGFA Is an Injury-Regulated Systemic Factor that Induces the Transition of Stem Cells into GAlert

    Directory of Open Access Journals (Sweden)

    Joseph T. Rodgers

    2017-04-01

    Full Text Available Summary: The activation of quiescent stem cells into the cell cycle is a key step in initiating the process of tissue repair. We recently reported that quiescent stem cells can transition into GAlert, a cellular state in which they have an increased functional ability to activate and participate in tissue repair. However, the precise molecular signals that induce GAlert in stem cells have remained elusive. Here, we show that the injury-induced regulation of hepatocyte growth factor (HGF proteolytic processing via the systemic protease, hepatocyte growth factor activator (HGFA, stimulates GAlert in skeletal muscle stem cells (MuSCs and fibro-adipogenic progenitors (FAPs. We demonstrate that administering active HGFA to animals is sufficient to induce GAlert in stem cells throughout the body and to significantly accelerate the processes of stem cell activation and tissue repair. Our data suggest that factors that induce GAlert will have broad therapeutic applications for regenerative medicine and wound healing. : Rodgers et al. show that HGFA is a systemic protease that is activated by tissue injury and relays a signal to stem cells in non-injured tissues that induces their transition into a primed, “GAlert” state in which they possess an enhanced potential to activate and repair tissue damage. Keywords: satellite cells, muscle stem cells, fibro-adipogenic progenitors, HGFA, HGF, mTORC1, cMet, stem cell quiescence, stem cell activation, GAlert

  7. Distinct transcriptomic features are associated with transitional and mature B-cell populations in the mouse spleen

    Directory of Open Access Journals (Sweden)

    Eden eKleiman

    2015-02-01

    Full Text Available Splenic transitional B-cells (T1 and T2 are selected to avoid self-reactivity and to safeguard against autoimmunity, then differentiate into mature follicular (FO-I and FO-II and marginal zone (MZ subsets. Transcriptomic analysis by RNA-seq of the five B-cell subsets revealed T1 cell signature genes included RAG suggesting a potential for receptor revision. T1 to T2 B-cell differentiation was marked by a switch from Myb to Myc, increased expression of the PI3K adapter DAP10 and MHC class II. FO-II may be an intermediate in FO-I differentiation and may also become MZ B-cells as suggested by principal component analysis (PCA. MZ B-cells possessed the most distinct transcriptome including downregulation of CD45 phosphatase-associated protein (CD45-AP/PTPRC-AP, as well as upregulation of IL-9R and innate molecules TLR3, TLR7 and bactericidal Perforin-2 (MPEG1. Among the endosomal TLRs, stimulation via TLR3 further enhanced Perforin-2 expression exclusively in MZ B-cells. Using gene-deleted and overexpressing transgenic mice we show that IL-9/IL-9R interaction resulted in rapid activation of STAT1, 3 and 5, primarily in MZ B-cells. Importantly, CD45-AP mutant mice had reduced transitional and increased mature MZ and FO B-cells, suggesting that it prevents premature entry of transitional B-cells to the mature B-cell pool or their survival and proliferation. Together, these findings suggest, developmental plasticity among splenic B-cell subsets, potential for receptor revision in peripheral tolerance whereas enhanced metabolism coincides with T2 to mature B-cell differentiation. Further, unique core transcriptional signatures in MZ B-cells may control their innate features.

  8. Transitional cell carcinoma of urethra with cardiac and pulmonary metastasis in a dog

    International Nuclear Information System (INIS)

    Serakides, R.; Rachid, M.A.; Veado, J.C.; Menezes, J.M.C.

    2000-01-01

    A case of urethral carcinoma in 15-year-old mongrel male dog is described. Signs of dysuria, urethral obstruction, tenesmus, pain and cough were mentioned. Clinically, the animal was undernourished and showed signs of pain and bladder repletion during the palpation of the abdominal region. Other complementary exams were made such as routine urinalyses, X-ray, ultrassonography and measurement of blood urea and creatinine. Macroscopically, the mucous membrane of pelvic urethra was somewhat irregular, due to the presence of several small white irregular and ulcerated nodules of imprecise boundaries. Similar nodules were found in the lungs and heart. Histologically, transitional cell carcinoma of urethra with metastasis to lung and heart was detected [pt

  9. Quantitative histopathology in the prognostic evaluation of patients with transitional cell carcinoma of the urinary bladder

    DEFF Research Database (Denmark)

    Sasaki, M; Sørensen, Flemming Brandt; Fukuzawa, S

    1993-01-01

    BACKGROUND: Morphologic grading of malignancy is considered to be of prognostic value in patients with transitional cell carcinomas of the urinary bladder (TCC). This qualitative approach is, however, associated with low reproducibility. Grading of malignancy can be carried out on a reproducible......, quantitative scale. METHODS: A retrospective, prognostic study of 110 patients treated for TCC in clinical Stages Ta-T4 (median follow-up time, 6 years) was performed, evaluating various grading techniques. Unbiased estimates of the volume-weighted mean nuclear volume (nuclear vV), nuclear volume fraction......, estimates of nuclear mean profile area (aH(nuc)), nuclear profile density index (NI), and mitotic profile density index (MI) were obtained by stereologic and morphometric techniques. RESULTS: The T-stage and morphologic grade of malignancy were closely cross-correlated (+0.63

  10. Quantitative histopathology in the prognostic evaluation of patients with transitional cell carcinoma of the urinary bladder

    DEFF Research Database (Denmark)

    Sasaki, M; Sørensen, Flemming Brandt; Fukuzawa, S

    1993-01-01

    BACKGROUND: Morphologic grading of malignancy is considered to be of prognostic value in patients with transitional cell carcinomas of the urinary bladder (TCC). This qualitative approach is, however, associated with low reproducibility. Grading of malignancy can be carried out on a reproducible......, quantitative scale. METHODS: A retrospective, prognostic study of 110 patients treated for TCC in clinical Stages Ta-T4 (median follow-up time, 6 years) was performed, evaluating various grading techniques. Unbiased estimates of the volume-weighted mean nuclear volume (nuclear vV), nuclear volume fraction...... of nuclear vV are prognostically superior to morphologic grading of malignancy in noninvasive TCC, whereas both morphologically and quantitatively based malignancy grading are without prognostic value in invasive TCC....

  11. Radiological and cytological detection of renal pelvic transitional-cell carcinoma

    International Nuclear Information System (INIS)

    Paeivaensalo, M.; Merikanto, J.; Myllylae, V.; Hellstroem, P.; Kallionen, M.; Jalovaara, P.; Oulu Univ.; Oulu Univ.

    1990-01-01

    We evaluated US, CT, intraveneous urography, arteriography, retrograde pyelography and urine cytology results in a series of 23 patients with renal pelvic transitional-cell carcinomas, 14 of whom underwent US, 17 i.v. urography, 8 CT, 15 arteriography, 9 retrograde pyelography, and 17 patients urine cytology. A tumour was identified in 5 patients (36%) at US, in 11 patients (61%) at urography, in 7 (88%) at CT, in 10 patients (67%) at arteriography, and in 8 (89%) at retrograde pyelography. Urine cytology was assessed as showing changes consistent with Papanicolaou class III-V in 15 (88%) of 17 patients. When renal pelvic cancer is suspected, intravenous urography should be performed as the initial radiological examination and followed by CT, which may also identify tumour spread. Arteriography and retrograde pyelography are sometimes complementary investigations. Repeated urinary cytology is mandatory. Our results show that US alone is unreliable in detecting renal pelvic cancer. (orig.) [de

  12. Mesenchymal stem cells promote cell invasion and migration and autophagy-induced epithelial-mesenchymal transition in A549 lung adenocarcinoma cells.

    Science.gov (United States)

    Luo, Dan; Hu, Shiyuan; Tang, Chunlan; Liu, Guoxiang

    2018-03-01

    Mesenchymal stem cells (MSCs) are recruited into the tumour microenvironment and promote tumour growth and metastasis. Tumour microenvironment-induced autophagy is considered to suppress primary tumour formation by impairing migration and invasion. Whether these recruited MSCs regulate tumour autophagy and whether autophagy affects tumour growth are controversial. Our data showed that MSCs promote autophagy activation, reactive oxygen species production, and epithelial-mesenchymal transition (EMT) as well as increased migration and invasion in A549 cells. Decreased expression of E-cadherin and increased expression of vimentin and Snail were observed in A549 cells cocultured with MSCs. Conversely, MSC coculture-mediated autophagy positively promoted tumour EMT. Autophagy inhibition suppressed MSC coculture-mediated EMT and reduced A549 cell migration and invasion slightly. Furthermore, the migratory and invasive abilities of A549 cells were additional increased when autophagy was further enhanced by rapamycin treatment. Taken together, this work suggests that microenvironments containing MSCs can promote autophagy activation for enhancing EMT; MSCs also increase the migratory and invasive abilities of A549 lung adenocarcinoma cells. Mesenchymal stem cell-containing microenvironments and MSC-induced autophagy signalling may be potential targets for blocking lung cancer cell migration and invasion. Copyright © 2018 John Wiley & Sons, Ltd.

  13. SPONTANEOUS AND MNNG-INDUCED REVERSION OF AN EGFP CONSTRUCT IN HELA CELLS: AN ASSAY FOR OBSERVING MUTATIONS IN LIVING CELLS BY FLUORESCENT MICROSCOPY

    Science.gov (United States)

    A HeLa cell line stably expressing the Enhanced Green Fluorescence Protein (EGFP) gene, interrupted by the IVS2-654 intron, was studied without treatment and after treatment with a single standard dose of 15 ?M of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). This assay was done ...

  14. Low doses ionizing radiation enhances the invasiveness of breast cancer cells by inducing epithelial-mesenchymal transition

    International Nuclear Information System (INIS)

    Zhang, Xin; Li, Xiaoyan; Zhang, Ning; Yang, Qifeng; Moran, Meena S.

    2011-01-01

    Highlights: → Low doses ionizing irradiation would enhance the invasiveness of breast cancer cells by inducing EMT. → Low doses ionizing radiation induced morphologic changes in breast cancer cells. → Low doses ionizing radiation led to upregulation of mesenchymal markers and down-regulation of epithelial markers. → Low doses ionizing radiation increased migration and invasion of breast cancer cells. -- Abstract: Epithelial-mesenchymal transition (EMT) is a process cellular morphologic and molecular alterations facilitate cell invasion. We hypothesized that low dose ionizing irradiation (LDIR) enhances the invasiveness of breast cancer cells by inducing EMT. The effects of LDIR on cellular morphology and the EMT markers of MCF-7 breast cancer cells were analyzed by western blot/RT-PCR and migration/invasion was examined using the transwell assay. We found that LDIR led to the phenotypic changes of EMT in MCF-7 cells and down-regulation of epithelial differentiation markers and transcriptional induction of mesenchymal markers. Furthermore, the radiated cells demonstrated enhanced migration/invasion MCF-7 cells compared with non-radiated cells. In summary, LDIR promotes the invasiveness of breast cancer cells through epithelial to mesenchymal transition. These findings may ultimately provide a new targeted approach for improving the therapeutic effectiveness of radiation in breast cancer.

  15. Incidence of spontaneous bacterial peritonitis in patients with ascites. Diagnostic value of white blood cell count and pH measurement in ascitic fluid

    DEFF Research Database (Denmark)

    Storgaard, J S; Svendsen, Jesper Hastrup; Hegnhøj, J

    1991-01-01

    During a 21-month period, 65 consecutive patients admitted with ascites were included in a prospective study of the incidence of spontaneous bacterial peritonitis, and paracentesis was performed on admission. The ascitic fluid was cultured, ascitic leucocytes were counted and pH was measured....... Bacterial growth was found in five patients with chronic liver disease, who were diagnosed as having spontaneous bacterial peritonitis (SBP), since no intra-abdominal focus could be demonstrated. Thus, the incidence of SBP in this material was 7.7% (95% confidence limits: 2.5-17%). SBP was caused...

  16. Relationship between circulating tumor cells and epithelial to mesenchymal transition in early breast cancer

    International Nuclear Information System (INIS)

    Mego, M.; Cierna, Z.; Janega, P.; Karaba, M.; Minarik, G.; Benca, J.; Sedlácková, T.; Sieberova, G.; Gronesova, P.; Manasova, D.; Pindak, D.; Sufliarsky, J.; Danihel, L.; Reuben, JM; Mardiak, J.

    2015-01-01

    Circulating tumor cells (CTCs) play a crucial role in tumor dissemination and are an independent survival predictor in breast cancer (BC) patients. Epithelial to mesenchymal transition (EMT) is involved in cancer invasion and metastasis. The aim of this study was to assess correlation between CTCs and expression of EMT transcription factors TWIST1 and SLUG in breast tumor tissue. This study included 102 early BC patients treated by primary surgery. Peripheral blood mononuclear cells (PBMC) were depleted of hematopoietic cells using RossetteSep™ negative selection kit. RNA extracted from CD45-depleted PBMC was interrogated for expression of EMT (TWIST1, SNAIL1, SLUG, FOXC2 and ZEB1) and epithelial (KRT19) gene transcripts by qRT-PCR. Expression of TWIST1 and SLUG in surgical specimens was evaluated by immunohistochemistry and quantified by multiplicative score. CTCs were detected in 24.5 % patients. CTCs exhibiting only epithelial markers were present in 8.8 % patients, whereas CTCs with only EMT markers were observed in 12.8 % of pts and CTCs co-expressing both markers were detected in 2.9 % pts. We observed lack of correlation between CTCs and expression of TWIST1 and SLUG in breast cancer cells or cancer associated stroma. Lack of correlation was observed for epithelial CTCs as well as for CTCs with EMT. In this translational study, we showed a lack of association between CTCs and expression of EMT-inducing transcription factors, TWIST1 and SLUG, in breast tumor tissue. Despite the fact that EMT is involved in cancer invasion and metastasis our results suggest, that expression of EMT proteins in unselected tumor tissue is not surrogate marker of CTCs with either mesenchymal or epithelial features

  17. Hypoxia induces a phase transition within a kinase signaling network in cancer cells.

    Science.gov (United States)

    Wei, Wei; Shi, Qihui; Remacle, Francoise; Qin, Lidong; Shackelford, David B; Shin, Young Shik; Mischel, Paul S; Levine, R D; Heath, James R

    2013-04-09

    Hypoxia is a near-universal feature of cancer, promoting glycolysis, cellular proliferation, and angiogenesis. The molecular mechanisms of hypoxic signaling have been intensively studied, but the impact of changes in oxygen partial pressure (pO2) on the state of signaling networks is less clear. In a glioblastoma multiforme (GBM) cancer cell model, we examined the response of signaling networks to targeted pathway inhibition between 21% and 1% pO2. We used a microchip technology that facilitates quantification of a panel of functional proteins from statistical numbers of single cells. We find that near 1.5% pO2, the signaling network associated with mammalian target of rapamycin (mTOR) complex 1 (mTORC1)--a critical component of hypoxic signaling and a compelling cancer drug target--is deregulated in a manner such that it will be unresponsive to mTOR kinase inhibitors near 1.5% pO2, but will respond at higher or lower pO2 values. These predictions were validated through experiments on bulk GBM cell line cultures and on neurosphere cultures of a human-origin GBM xenograft tumor. We attempt to understand this behavior through the use of a quantitative version of Le Chatelier's principle, as well as through a steady-state kinetic model of protein interactions, both of which indicate that hypoxia can influence mTORC1 signaling as a switch. The Le Chatelier approach also indicates that this switch may be thought of as a type of phase transition. Our analysis indicates that certain biologically complex cell behaviors may be understood using fundamental, thermodynamics-motivated principles.

  18. Hypoxia induces a phase transition within a kinase signaling network in cancer cells

    Science.gov (United States)

    Wei, Wei; Shi, Qihui; Remacle, Francoise; Qin, Lidong; Shackelford, David B.; Shin, Young Shik; Mischel, Paul S.; Levine, R. D.; Heath, James R.

    2013-01-01

    Hypoxia is a near-universal feature of cancer, promoting glycolysis, cellular proliferation, and angiogenesis. The molecular mechanisms of hypoxic signaling have been intensively studied, but the impact of changes in oxygen partial pressure (pO2) on the state of signaling networks is less clear. In a glioblastoma multiforme (GBM) cancer cell model, we examined the response of signaling networks to targeted pathway inhibition between 21% and 1% pO2. We used a microchip technology that facilitates quantification of a panel of functional proteins from statistical numbers of single cells. We find that near 1.5% pO2, the signaling network associated with mammalian target of rapamycin (mTOR) complex 1 (mTORC1)—a critical component of hypoxic signaling and a compelling cancer drug target—is deregulated in a manner such that it will be unresponsive to mTOR kinase inhibitors near 1.5% pO2, but will respond at higher or lower pO2 values. These predictions were validated through experiments on bulk GBM cell line cultures and on neurosphere cultures of a human-origin GBM xenograft tumor. We attempt to understand this behavior through the use of a quantitative version of Le Chatelier’s principle, as well as through a steady-state kinetic model of protein interactions, both of which indicate that hypoxia can influence mTORC1 signaling as a switch. The Le Chatelier approach also indicates that this switch may be thought of as a type of phase transition. Our analysis indicates that certain biologically complex cell behaviors may be understood using fundamental, thermodynamics-motivated principles. PMID:23530221

  19. Self energy QED: Multipole spontaneous emission

    International Nuclear Information System (INIS)

    Salamin, Y.I.

    1990-08-01

    Within the context of Barut's self-field approach, we write the exact expression of the spontaneous atomic decay rate (Phys. Rev. A37, 2284 (1988)), in the long wavelength approximation, in terms of electric- and magnetic-like multipole contributions which are related to the matrix elements of the transition charge and current distributions of the relativistic electron. A number of features of these expressions are discussed and their generalization to interacting composite systems is also pointed out. (author). 8 refs

  20. Paeonol attenuates aging MRC-5 cells and inhibits epithelial-mesenchymal transition of premalignant HaCaT cells induced by aging MRC-5 cell-conditioned medium.

    Science.gov (United States)

    Yang, Lihua; Xing, Shangping; Wang, Kun; Yi, Hua; Du, Biaoyan

    2018-02-01

    Senescence-associated secretory phenotype (SASP) factors, such as IL-6 and IL-8, are extremely critical in tissue microenvironment. Senescent human fibroblasts facilitate epithelial-mesenchymal transition (EMT) in premalignant epithelial cells mainly through the secretion of SASP factors. Meanwhile, premalignant human HaCaT Keratinocyte (HaCaT) cells as immortal epithelial cells are susceptible to malignant transformation. Paeonol, an herbal phenolic component found in peonies, exerts anti-aging and anti-tumor efficacies, while the molecular mechanisms of paeonol on EMT in premalignant HaCaT cells induced by SASP factors are unclear. In this study, we first established a senescent human fetal lung fibroblast MRC-5 cell model using hydrogen peroxide evaluated by senescence-associated β-galactosidase assay. Upon paeonol treatment, intracellular reactive oxygen species levels in aging MRC-5 cells were significantly decreased via regulation of nuclear translocation of Nrf2. Then we curiously studied whether the aging MRC-5 cell-conditioned medium could induce EMT in premalignant HaCaT cells, and the results showed that paeonol significantly reduced the clonogenic, migratory, and invasive capacities of premalignant HaCaT cells potentially induced by IL-6 and IL-8. Moreover, we found that paeonol notably altered pluripotency of EMT-associated markers via the modulation of ERK and TGF-β1/Smad pathway in premalignant HaCaT cells. These findings suggest that paeonol may be used as an adjuvant therapy for SASP factor-mediated EMT in premalignant lesion.

  1. Dewetting transition assisted clearance of (NFGAILS) amyloid fibrils from cell membranes by graphene

    International Nuclear Information System (INIS)

    Liu, Jiajia; Yang, Zaixing; Gu, Zonglin; Li, Haotian; Garate, Jose Antonio; Zhou, Ruhong

    2014-01-01

    Clearance of partially ordered oligomers and monomers deposited on cell membrane surfaces is believed to be an effective route to alleviate many potential protein conformational diseases (PCDs). With large-scale all-atom molecular dynamics simulations, here we show that graphene nanosheets can easily and quickly win a competitive adsorption of human islet amyloid polypeptides (hIAPP 22-28 ) NFGAILS and associated fibrils against cell membrane, due to graphene's unique two-dimensional, highly hydrophobic surface with its all-sp 2 hybrid structure. A nanoscale dewetting transition was observed at the interfacial region between the fibril (originally deposited on the membrane) and the graphene nanosheet, which significantly assisted the adsorption of fibrils onto graphene from the membrane. The π–π stacking interaction between Phe23 and graphene played a crucial role, providing the driving force for the adsorption at the graphene surface. This study renders new insight towards the importance of water during the interactions between amyloid peptides, the phospholipidic membrane, and graphene, which might shed some light on future developments of graphene-based nanomedicine for preventing/curing PCDs like type II diabetes mellitus

  2. Excitonic nature of optical transitions in electroabsorption spectra of perovskite solar cells

    Science.gov (United States)

    Ruf, Fabian; Magin, Alice; Schultes, Moritz; Ahlswede, Erik; Kalt, Heinz; Hetterich, Michael

    2018-02-01

    We investigate the electronic structure of solution-processed perovskite solar cells using temperature-dependent electroabsorption (EA) spectroscopy. Simultaneous measurements of absorption and electromodulated spectra of semitransparent methylammonium lead iodide solar cells facilitate a direct comparison of the specific features. The EA spectra can be transformed to peak-like line shapes utilizing an approach based on the Kramers-Kronig relations. The resulting peak positions correspond well to the discrete excitonic—rather than the continuum—contribution of the absorption spectra derived from generalized Elliott fits. This indicates the excitonic nature of the observed EA resonance and is found to be consistent over the whole temperature range investigated (from T = 10 K up to room temperature). To further confirm these findings, a line shape analysis of the measured EA spectra was performed. The best agreement was achieved using a first-derivative-like functional form which is expected for excitonic systems and supports the conclusion of an excitonic optical transition. Exciton binding energies EB are estimated for the orthorhombic and tetragonal phases as 26 meV and 19 meV, respectively. Nevertheless, power-conversion efficiencies η up to 13% (11.5% stabilized) demonstrate good charge-carrier separation in the devices due to sufficient thermal dissociation and Sommerfeld-enhanced absorption.

  3. Spectroscopic cell for fast pressure jumps across the glass transition line

    Science.gov (United States)

    Di Leonardo, R.; Scopigno, T.; Ruocco, G.; Buontempo, U.

    2004-08-01

    We present an experimental protocol for the spectroscopic study of the dynamics of glasses in the aging regime induced by sudden pressure jumps (crunches) across the glass transition line. The sample, initially in the liquid state, is suddenly brought in the glassy state, and therefore out of equilibrium, in a four-window optical crunch cell which is able to perform pressure jumps of 3 Kbar in a time interval of ≈10 ms. The main advantages of this setup with respect to previous pressure-jump systems is that the pressure jump is induced through a pressure transmitting fluid mechanically coupled to the sample stage through a deformable membrane, thus avoiding any flow of the sample itself in the pressure network and allowing us to deal with highly viscous materials. The dynamics of the sample during the aging regime is investigated by Brillouin light scattering. For this purpose the crunch cell is used in conjunction with a high resolution double monochromator equipped with a charge-coupled device detector. This system is able to record a full spectrum of a typical glass forming material in a single 1 s shot. As an example we present the study of the evolution toward equilibrium of the infinite frequency longitudinal elastic modulus (M∞) of low molecular weight polymer [Poly(bisphenol A-co-epichlorohydrin), glycidyl end capped]. The observed time evolution of M∞, well represented by a single stretched exponential, is interpreted within the framework of the Tool-Narayanaswamy theory.

  4. Design features of the A-cell and transition coils of MFTF-B

    International Nuclear Information System (INIS)

    Tatro, R.E.; Wohlwend, J.W.; Ring, D.S.

    1981-01-01

    The MFTF-B transition coil and A-cell magnet designs use variations of the copper-stabilized NbTi conductor developed by LLNL for the MFTF Yin-Yang magnets. This conductor will be wound on the one inch thick (12.7 mm) stainless steel coil forms using a two-axis winding machine similar to the existing LLNL Yin-Yang winding machine. After winding, covers will be placed over the coil and welded to the coil form to form a helium-tight jacket around the conductor. These jacketed coils are then enclosed in thick structural cases that react the large Lorentz forces on the magnets. The space between the coil jacket and case will be filled by a stainless steel bladder that will be injected with urethane. The injection bladder will provide cooling passages during cooldown as well as transmitting the Lorentz forces between the jacket and the case. The large self-equilibrating lobe-spreading forces on the magnets (29.10 6 lb, 127.0 MN) for the A-cell are reacted primarily through the thick 304 LN case into the external superstructure. The net Lorentz forces and the inertial forces on the magnet are reacted through support systems into the LLNL vacuum vessel structure

  5. Rare Association of Anti-Hu Antibody Positive Paraneoplastic Neurological Syndrome and Transitional Cell Bladder Carcinoma

    Directory of Open Access Journals (Sweden)

    S. Lukacs

    2012-01-01

    Full Text Available Introduction. Paraneoplastic encephalomyelitis (PEM and subacute sensory neuronopathy (SSN are remote effects of cancer, usually associated with small-cell lung carcinoma and positive anti-Hu antibody. We describe the rare association of bladder transitional cell carcinoma (TCC with anti-Hu antibody positivity resulting in this paraneoplastic neurological syndrome. Patient. A 76-year-old female presented with bilateral muscle weakness and paraesthesia of the upper and lower limbs in a length-dependent “glove and stocking” distribution. Central nervous system symptoms included cognitive problems, personality change, and truncal ataxia. Case notes and the literature were reviewed. Result. Autoantibody screening was positive for anti-Hu antibody (recently renamed antineuronal nuclear antibody 1, ANNA-1. The diagnosis of PEM and SSN was supported by MRI and lumbar puncture results. A superficial bladder TCC was demonstrated on CT and subsequently confirmed on histology. No other primary neoplasm was found on full-body imaging. The neurological symptoms were considered to be an antibody-mediated paraneoplastic neurological syndrome and improved after resection of the tumour. Discussion. The association of anti-Hu positive paraneoplastic neurological syndrome and TCC has not been described in the literature previously. We emphasize the need for detailed clinical examination and the importance of a multidisciplinary thought process and encourage further awareness of this rare association.

  6. Dewetting transition assisted clearance of (NFGAILS) amyloid fibrils from cell membranes by graphene

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jiajia; Yang, Zaixing; Gu, Zonglin [Institute of Quantitative Biology and Medicine, SRMP and RAD-X, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, and Jiangsu Provincial Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123 (China); Li, Haotian [Bio-X Lab, Department of Physics, Zhejiang University, Hangzhou 310027 (China); Garate, Jose Antonio [IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Zhou, Ruhong, E-mail: ruhongz@us.ibm.com [Institute of Quantitative Biology and Medicine, SRMP and RAD-X, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, and Jiangsu Provincial Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123 (China); IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Department of Chemistry, Columbia University, New York, New York 10027 (United States)

    2014-12-14

    Clearance of partially ordered oligomers and monomers deposited on cell membrane surfaces is believed to be an effective route to alleviate many potential protein conformational diseases (PCDs). With large-scale all-atom molecular dynamics simulations, here we show that graphene nanosheets can easily and quickly win a competitive adsorption of human islet amyloid polypeptides (hIAPP{sub 22-28}) NFGAILS and associated fibrils against cell membrane, due to graphene's unique two-dimensional, highly hydrophobic surface with its all-sp{sup 2} hybrid structure. A nanoscale dewetting transition was observed at the interfacial region between the fibril (originally deposited on the membrane) and the graphene nanosheet, which significantly assisted the adsorption of fibrils onto graphene from the membrane. The π–π stacking interaction between Phe23 and graphene played a crucial role, providing the driving force for the adsorption at the graphene surface. This study renders new insight towards the importance of water during the interactions between amyloid peptides, the phospholipidic membrane, and graphene, which might shed some light on future developments of graphene-based nanomedicine for preventing/curing PCDs like type II diabetes mellitus.

  7. Immunoglobulin V(H) gene sequence analysis of spontaneous murine immunoglobulin secreting B-cell tumours with clinical features of human disease

    NARCIS (Netherlands)

    Zhu, D.; Arkel, C. van; King, C.A.; Meirvenne, S. van; Greef, C. de; Thielemans, K.; Radl, J.; Stevenson, F.K.

    1998-01-01

    The 5T series of multiple myelomas (MM) and Waldenstrsom's macroglobulinaemia-like lymphomas (WM), which developed spontaneously in ageing mice of the C57BL/KaLwRij strain, shows clinical and biological features that closely resemble their corresponding human diseases. In order to compare the

  8. On the Origin of Prostate Cancer Stem Cells through Transmissible ER Stress-Mediated Epithelial to Mesenchymal Transition

    Science.gov (United States)

    2013-10-01

    elucidate if in fact this ressitance to secondary UPR induction (“fitness”) plays a role in more physiologically-relevant stressful conditions. To...transmissible ER Stress (TERS), exhibit many key characteristics of an epithelial-to-mesenchymal transition.  TERS-treated prostate cancer cells also...treated cells exhibit an activation of the Wnt-signaling pathway  Twist expression is directly linked with the presence of TERS  TERS induces

  9. A miniature single element effusion cell for the vacuum deposition of transition-metal and rare-earth elements

    Science.gov (United States)

    Harris, V. G.; Koon, N. C.

    1997-08-01

    A miniature single element effusion cell has been fabricated and tested that allows for the high-vacuum deposition of a variety of transition-metal and rare-earth elements. The cell is designed to operate under high-vacuum conditions, ≈10-9 Torr, with low power demands, <200 W. The virtues of this evaporator are the simplicity of design and ease of fabrication, assembly, maintenance, and operation.

  10. Estimation of transition doses for human glioblastoma, neuroblastoma and prostate cell lines using the linear-quadratic formalism

    Directory of Open Access Journals (Sweden)

    John Akudugu

    2015-09-01

    Full Text Available Purpose: The introduction of stereotactic radiotherapy has raised concerns regarding the use of the linear-quadratic (LQ model for predicting radiation response for large fractional doses. To partly address this issue, a transition dose D* below which the LQ model retains its predictive strength has been proposed. Estimates of D* which depends on the a, β, and D0 parameters are much lower than fractional doses typically encountered in stereotactic radiotherapy. D0, often referred to as the final slope of the cell survival curve, is thought to be constant. In vitro cell survival curves generally extend over the first few logs of cell killing, where D0-values derived from the multi-target formalism may be overestimated and can lead to low transition doses. Methods:  D0-values were calculated from first principles for each decade of cell killing, using experimentally-determined a and β parameters for 17 human glioblastoma, neuroblastoma, and prostate cell lines, and corresponding transition doses were derived.Results: D0 was found to decrease exponentially with cell killing. Using D0-values at cell surviving fractions of the order of 10-10 yielded transition doses ~3-fold higher than those obtained from D0-values obtained from conventional approaches. D* was found to increase from 7.84 ± 0.56, 8.91 ± 1.20, and 6.55 ± 0.91 Gy to 26.84 ± 2.83, 23.95 ± 2.03, and 22.49 ± 2.31 Gy for the glioblastoma, neuroblastoma, and prostate cell lines, respectively. Conclusion: These findings suggest that the linear-quadratic formalism might be valid for estimating the effect of stereotactic radiotherapy with fractional doses in excess of 20 Gy.

  11. Analysis of spontaneous tumor-specific CD4 T-cell immunity in lung cancer using promiscuous HLA-DR telomerase-derived epitopes: potential synergistic effect with chemotherapy response.

    Science.gov (United States)

    Godet, Yann; Fabre, Elizabeth; Dosset, Magalie; Lamuraglia, Michele; Levionnois, Emeline; Ravel, Patrice; Benhamouda, Nadine; Cazes, Aurélie; Le Pimpec-Barthes, Françoise; Gaugler, Beatrice; Langlade-Demoyen, Pierre; Pivot, Xavier; Saas, Philippe; Maillère, Bernard; Tartour, Eric; Borg, Christophe; Adotévi, Olivier

    2012-05-15

    To investigate the presence and impact of spontaneous telomerase-specific CD4 T-cell responses in cancer patients. A multistep approach was used to design novel pan-HLA-DR-restricted peptides from telomerase. T-cell clones isolated from cancer patients were used to characterize the polarization of telomerase-specific CD4 response. The presence of spontaneous CD4 T-cell response against telomerase was monitored in 84 metastatic non-small cell lung cancer (NSCLC) patients before first-line chemotherapy (CT) using IFN-γ ELISPOT assay. Then we analyzed the impact of the pretherapeutic telomerase-specific CD4 T immunity on clinical outcome in patients according to their respective response to CT. We described four novel telomerase-derived CD4 epitopes referred as universal cancer peptides (UCP) that effectively bind to most commonly found human MHC class II alleles. UCP-specific CD4 T-cell repertoire is present in human and UCP-specific CD4 T-cell clones generated from cancer patients exhibited high avidity and are Th1 polarized. Significant frequency (38%) of naturally occurring UCP-specific T-cell responses were detected before CT in advanced NSCLC but not in healthy volunteers. This response was shown to significantly increase overall survival (OS) of patients responding to CT (Median OS: 53 vs. 40 weeks, P = 0.034). These results show for the first time a potential synergistic effect of telomerase-specific CD4 T-cell response with CT response in NSCLC and underline the potential role of tumor-specific CD4 T-cell response on the efficiency of conventional anticancer therapy. ©2012 AACR.

  12. Qualitative and quantitative histopathology in transitional cell carcinomas of the urinary bladder. An international investigation of intra- and interobserver reproducibility

    DEFF Research Database (Denmark)

    Sørensen, Flemming Brandt; Sasaki, M; Fukuzawa, S

    1994-01-01

    BACKGROUND: Histopathologic, prognosis-related grading of malignancy by means of morphologic examination in transitional cell carcinomas of the urinary bladder (TCC) may be subject to observer variation, resulting in a reduced level of reproducibility. This may confound comparisons of treatment r...

  13. Solitary Laryngeal Metastasis from Transitional Cell Carcinoma of the Kidney: Clinical Case and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Tarek Assi

    2015-01-01

    Full Text Available The urogenital tract is a rare origin of laryngeal metastasis; transitional cell carcinoma with laryngeal metastases had never been reported previously. In this paper, we describe the clinical and pathological characteristics, evolution, and treatment of the first reported case of a laryngeal metastasis of a TCC followed by a brief review of the literature.

  14. Complete en bloc urinary exenteration for synchronous multicentric transitional cell carcinoma with sarcomatoid features in a hemodialysis patient

    Directory of Open Access Journals (Sweden)

    Tiberio M. Siqueira Jr

    2006-10-01

    Full Text Available The incidence of transitional cell carcinoma (TCC in patients submitted to hemodialysis is low. The presence of TCC with sarcomatoid features in this cohort is even scarcer. Herein, we describe a very rare case of synchronous multicentric muscle invasive bladder carcinoma with prostate invasion in a hemodialysis patient, submitted to complete en bloc urinary exenteration.

  15. AM251 Suppresses Epithelial-Mesenchymal Transition of Renal Tubular Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Tomoyo Yoshinaga

    Full Text Available Epithelial-mesenchymal transition (EMT of renal tubular epithelial cells is one of the causative mechanisms of kidney fibrosis. In our study, we screened lipophilic compounds using a lipid library including approximately 200 lipids to identify those that suppressed EMT induced by a transforming growth factor (TGF-β1 stimulus. Initial screening was performed with the immortalized HK-2 renal tubule epithelial cell line. The most promising compounds were further tested in RPTEC primary renal tubule epithelial cells. We found that the synthetic lipid AM251 suppressed two hallmark events associated with EMT, the upregulation of collagen 1A1 (COL1A1 and downregulation of E-cadherin. Though AM251 is known to act as an antagonist for the cannabinoid receptor type 1 (CB1 and an agonist for the G protein-coupled receptor 55 (GRP55, the suppression of EMT by AM251 was not mediated through either receptor. Microarray analyses revealed that AM251 inhibited induction of several EMT transcription factors such as SNAIL1, which is the key inducer of EMT, and the AP-1 transcription factors FOSB and JUNB. Activation of SMAD2/3 and p38 mitogen-activated protein kinase (MAPK was inhibited by AM251, with greater inhibition of the latter, indicating that AM251 acted upstream of SMAD/p38 MAPK in the TGF-β signaling pathway. Our findings regarding the effects of AM251 on the TGF-β signaling pathway may inform development of a novel therapeutic agent suppressing EMT, thus preventing kidney fibrosis.

  16. Cancer stem cells, epithelial-mesenchymal transition, and drug resistance in high-grade ovarian serous carcinoma.

    Science.gov (United States)

    Chen, Xiaoxiang; Zhang, Jing; Zhang, Zhihong; Li, Hongxia; Cheng, Wenjun; Liu, Jinsong

    2013-11-01

    Although epithelial ovarian cancer cells are eliminated by debulking surgery and chemotherapy during initial treatment, it is believed that only a subset of cancer cells, that is, cancer stem cells, may be an important source of tumor recurrence and drug resistance. This review highlights our current understanding of high-grade serous carcinoma, ovarian cancer stem cells, common methods for enrichment of ovarian cancer stem cells, mechanisms involved in drug resistance, and potential strategies for overcoming drug resistance, with associated potential controversies and pitfalls. We also review the potential relationship between epithelial-to-mesenchymal transition and cancer stem cells and how we can induce cancer cells to differentiate into benign stromal fibroblasts in response to certain chemotherapy drugs. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Characterization of a single peptide derived from cytochrome P4501B1 that elicits spontaneous human leukocyte antigen (HLA)-A1 as well as HLA-B35 restricted CD8 T-cell responses in cancer patients

    DEFF Research Database (Denmark)

    Kvistborg, P.; Hadrup, S.R.; Andersen, M.H.

    2008-01-01

    Cytochrome P450 1B1 (CYP1B1) is widely expressed in human malignancies, but silent in most normal tissues. Importantly, the protein is believed to play an important role in the survival and growth of cancer cells in a stressed environment, e.g., as a result of hypoxia or chemotherapy. Thus......, targeting of CYP1B1 represents a potentially successful strategy in the treatment of metastatic cancer, e.g., by therapeutic vaccination. Herein, we describe the characterization of a novel peptide from the CYP1B1 protein (CYP240), which is spontaneously recognized by CD8 T cells in cancer patients....... Rare but strong responses were detected in HLA-A1-positive patients, and more frequent responses were detected in HLA-B35-positive patients. No reactivity against the peptide could be detected in healthy donors. Furthermore, we demonstrated that peptide-specific T cells were able to lyze target cells...

  18. Canine Mammary Cancer Stem Cells are Radio- and Chemo-Resistant and Exhibit an Epithelial-Mesenchymal Transition Phenotype

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Lisa Y., E-mail: lisa.pang@ed.ac.uk; Cervantes-Arias, Alejandro; Else, Rod W.; Argyle, David J. [Royal (Dick) School of Veterinary Studies and Roslin Institute, The University of Edinburgh, Easter Bush, Midlothian, EH25 9RG (United Kingdom)

    2011-03-30

    Canine mammary carcinoma is the most common cancer among female dogs and is often fatal due to the development of distant metastases. In humans, solid tumors are made up of heterogeneous cell populations, which perform different roles in the tumor economy. A small subset of tumor cells can hold or acquire stem cell characteristics, enabling them to drive tumor growth, recurrence and metastasis. In veterinary medicine, the molecular drivers of canine mammary carcinoma are as yet undefined. Here we report that putative cancer stem cells (CSCs) can be isolated form a canine mammary carcinoma cell line, REM134. We show that these cells have an increased ability to form tumorspheres, a characteristic of stem cells, and that they express embryonic stem cell markers associated with pluripotency. Moreover, canine CSCs are relatively resistant to the cytotoxic effects of common chemotherapeutic drugs and ionizing radiation, indicating that failure of clinical therapy to eradicate canine mammary cancer may be due to the survival of CSCs. The epithelial to mesenchymal transition (EMT) has been associated with cancer invasion, metastasis, and the acquisition of stem cell characteristics. Our results show that canine CSCs predominantly express mesenchymal markers and are more invasive than parental cells, indicating that these cells have a mesenchymal phenotype. Furthermore, we show that canine mammary cancer cells can be induced to undergo EMT by TGFβ and that these cells have an increased ability to form tumorspheres. Our findings indicate that EMT induction can enrich for cells with CSC properties, and provide further insight into canine CSC biology.

  19. Canine Mammary Cancer Stem Cells are Radio- and Chemo-Resistant and Exhibit an Epithelial-Mesenchymal Transition Phenotype

    International Nuclear Information System (INIS)

    Pang, Lisa Y.; Cervantes-Arias, Alejandro; Else, Rod W.; Argyle, David J.

    2011-01-01

    Canine mammary carcinoma is the most common cancer among female dogs and is often fatal due to the development of distant metastases. In humans, solid tumors are made up of heterogeneous cell populations, which perform different roles in the tumor economy. A small subset of tumor cells can hold or acquire stem cell characteristics, enabling them to drive tumor growth, recurrence and metastasis. In veterinary medicine, the molecular drivers of canine mammary carcinoma are as yet undefined. Here we report that putative cancer stem cells (CSCs) can be isolated form a canine mammary carcinoma cell line, REM134. We show that these cells have an increased ability to form tumorspheres, a characteristic of stem cells, and that they express embryonic stem cell markers associated with pluripotency. Moreover, canine CSCs are relatively resistant to the cytotoxic effects of common chemotherapeutic drugs and ionizing radiation, indicating that failure of clinical therapy to eradicate canine mammary cancer may be due to the survival of CSCs. The epithelial to mesenchymal transition (EMT) has been associated with cancer invasion, metastasis, and the acquisition of stem cell characteristics. Our results show that canine CSCs predominantly express mesenchymal markers and are more invasive than parental cells, indicating that these cells have a mesenchymal phenotype. Furthermore, we show that canine mammary cancer cells can be induced to undergo EMT by TGFβ and that these cells have an increased ability to form tumorspheres. Our findings indicate that EMT induction can enrich for cells with CSC properties, and provide further insight into canine CSC biology

  20. Spontaneous Atraumatic Mediastinal Hemorrhage

    Directory of Open Access Journals (Sweden)

    Morkos Iskander BSc, BMBS, MRCS, PGCertMedEd

    2013-04-01

    Full Text Available Spontaneous atraumatic mediastinal hematomas are rare. We present a case of a previously fit and well middle-aged lady who presented with acute breathlessness and an increasing neck swelling and spontaneous neck bruising. On plain chest radiograph, widening of the mediastinum was noted. The bruising was later confirmed to be secondary to mediastinal hematoma. This life-threatening diagnostic conundrum was managed conservatively with a multidisciplinary team approach involving upper gastrointestinal and thoracic surgeons, gastroenterologists, radiologists, intensivists, and hematologists along with a variety of diagnostic modalities. A review of literature is also presented to help surgeons manage such challenging and complicated cases.

  1. Human testis-derived embryonic stem cell-like cells are not pluripotent, but possess potential of mesenchymal progenitors

    NARCIS (Netherlands)

    Chikhovskaya, J. V.; Jonker, M. J.; Meissner, A.; Breit, T. M.; Repping, S.; van Pelt, A. M. M.

    2012-01-01

    BACKGROUND: Spontaneous in vitro transition of undifferentiated spermatogonia into the pluripotent cell state has been achieved using neonatal and adult mouse testis tissue. In an effort to establish an analogous source of human patient-specific pluripotent stem cells, several research groups have

  2. Active suppression of host-vs-graft reaction in pregnant mice. VII. Spontaneous abortion of allogeneic CBA/J x DBA/2 fetuses in the uterus of CBA/J mice correlates with deficient non-T suppressor cell activity

    International Nuclear Information System (INIS)

    Clark, D.A.; Chaput, A.; Tutton, D.

    1986-01-01

    The mammalian fetus has been viewed as an unusually successful type of allograft and unexplained spontaneous abortion as a possible example of maternal rejection. Previous studies have shown the presence of small lymphocytic suppressor cells in the murine decidua which block the generation and reactivation of anti-paternal cytotoxic T lymphocytes (CTL) and lymphokine-activated killer cells (LAK) by elaborating a factor that inhibits the response to interleukin 2 (IL 2). A deficiency of these suppressor cells was associated with implants of xenogeneic Mus caroli embryos in the Mus musculus uterus which are infiltrated by maternal lymphoid cells and aborted. A deficiency of such suppressor cells in the lymph nodes draining the uterus of CBA/J females in the process of aborting their semi-allogeneic CBA x DBA/2 F 1 progeny has also been shown. CBA/J females possess significantly lower levels of decidua-associated non-T suppressor cells on day 8.5 to 10.5 of allopregnancy than do mothers that will produce large litters of live babies. The F 1 embryos are infiltrated by maternal lymphocytes prior to abortion, and the infiltration and abortion rate appears to be augmented by pre-immunization with paternal DBA/2 spleen cells. The CBA/J x DBA/2J mating combination provides a model of spontaneous abortion in which immunologic factors play an important role and demonstrates that the association between deficiency of decidua-associated suppressor cells and xenopregnancy failure also holds true for the failure of allopregnancies resulting from natural within-species mating

  3. Heterogeneity of expression of epithelial-mesenchymal transition (EMT markers in melanocytes and melanoma cell lines

    Directory of Open Access Journals (Sweden)

    Ji Eun eKim

    2013-05-01

    Full Text Available The epithelial-mesenchymal transition (EMT describes a reversible switch from an epithelial-like to a mesenchymal-like phenotype. It is essential for the development of the normal epithelium and also contributes to the invasive properties of carcinomas. At the molecular level, the EMT transition is characterised by a series of coordinated changes including downregulation of the junctional protein E-cadherin (CDH1, up-regulation of transcriptional repressors of E-cadherin such as Snail (SNAI1 and Slug (SNAI2, and up-regulation of N-cadherin. We wished to determine whether cultured normal melanocytes and melanoma cell lines, which are derived from the neural crest, showed signs of a similarly coordinated phenotypic switch. We investigated normal melanocytes and 25 cell lines derived from New Zealand patients with metastatic melanoma. Most lines had been previously genotyped for common mutations such as BRAF, NRAS, PIK3CA, TP53 and CDKN2A. Expression of E-cadherin, N-cadherin, MITF, Snail, Slug, Axl, p53 and Hdm2 was compared by western blotting. Normal melanocytes expressed each of these proteins except for Snail, while normal melanocytes and almost every melanoma line expressed Slug. Expression of individual markers among different melanoma lines varied from high to low or undetectable. Quantitation of western blots showed that expression of MITF-M, the melanocyte-specific isoform of MITF, was positively related to that of E-cadherin but inversely related to that of N-cadherin and Axl. There was also no apparent relationship between expression of any particular marker and the presence of BRAF, NRAS, PIK3CA, TP53 or CDKN2A mutations. The results suggest that melanomas do not show the classical epithelial and mesenchymal phenotypes but rather display either high E-cadherin/high MITF-M expression on one hand, or high N-cadherin/high Axl expression on the other. These may correspond to differentiated and invasive phenotypes in vivo.

  4. Rapamycin inhibits FBXW7 loss-induced epithelial-mesenchymal transition and cancer stem cell-like characteristics in colorectal cancer cells

    OpenAIRE

    Wang, Yuli; Liu, Yueyong; Lu, Jing; Zhang, Pengju; Wang, Yunshan; Xu, Yangyang; Wang, Zeran; Mao, Jian-Hua; Wei, Guangwei

    2013-01-01

    Increased cell migration and invasion lead to cancer metastasis and are crucial to cancer prognosis. In this study, we explore whether FBXW7 plays any role in metastatic process. We show that depletion of FBXW7 induces epithelial-mesenchymal transition (EMT) in human colon cancer cells along with the increase in cell migration and invasion. Moreover, FBXW7 deficiency promotes the generation of colon cancer stem-like cells in tumor-sphere culture. mTOR inhibition by rapamycin suppresses FBXW7 ...

  5. T. brucei infection reduces B lymphopoiesis in bone marrow and truncates compensatory splenic lymphopoiesis through transitional B-cell apoptosis.

    Directory of Open Access Journals (Sweden)

    Viki Bockstal

    2011-06-01

    Full Text Available African trypanosomes of the Trypanosoma brucei species are extracellular protozoan parasites that cause the deadly disease African trypanosomiasis in humans and contribute to the animal counterpart, Nagana. Trypanosome clearance from the bloodstream is mediated by antibodies specific for their Variant Surface Glycoprotein (VSG coat antigens. However, T. brucei infection induces polyclonal B cell activation, B cell clonal exhaustion, sustained depletion of mature splenic Marginal Zone B (MZB and Follicular B (FoB cells, and destruction of the B-cell memory compartment. To determine how trypanosome infection compromises the humoral immune defense system we used a C57BL/6 T. brucei AnTat 1.1 mouse model and multicolor flow cytometry to document B cell development and maturation during infection. Our results show a more than 95% reduction in B cell precursor numbers from the CLP, pre-pro-B, pro-B, pre-B and immature B cell stages in the bone marrow. In the spleen, T. brucei induces extramedullary B lymphopoiesis as evidenced by significant increases in HSC-LMPP, CLP, pre-pro-B, pro-B and pre-B cell populations. However, final B cell maturation is abrogated by infection-induced apoptosis of transitional B cells of both the T1 and T2 populations which is not uniquely dependent on TNF-, Fas-, or prostaglandin-dependent death pathways. Results obtained from ex vivo co-cultures of living bloodstream form trypanosomes and splenocytes demonstrate that trypanosome surface coat-dependent contact with T1/2 B cells triggers their deletion. We conclude that infection-induced and possibly parasite-contact dependent deletion of transitional B cells prevents replenishment of mature B cell compartments during infection thus contributing to a loss of the host's capacity to sustain antibody responses against recurring parasitemic waves.

  6. Hypoxia inducible factor-1α-dependent epithelial to mesenchymal transition under hypoxic conditions in prostate cancer cells.

    Science.gov (United States)

    Li, Mingchuan; Wang, Yong Xing; Luo, Yong; Zhao, Jiahui; Li, Qing; Zhang, Jiao; Jiang, Yongguang

    2016-07-01

    Prostate cancer is the most commonly diagnosed cancer in men and the second leading cause of cancer death. Hypoxia is an environmental stimulus that plays an important role in the development and cancer progression especially for solid tumors. The key regulator under hypoxic conditions is stabilized hypoxia-inducible factor (HIF)-1α. In the present study, immune-fluorescent staining, siRNAs, qRT-PC, immunoblotting, cell migration and invasion assays were carried out to test typical epithelial to mesenchymal transition under hypoxia and the key regulators of this process in PC3, a human prostate cancer cell line. Our data demonstrated that hypoxia induces diverse molecular, phenotypic and functional changes in prostate cancer cells that are consistent with EMT. We also showed that a cell signal factor such as HIF-1α, which might be stabilized under hypoxic environment, is involved in EMT and cancer cell invasive potency. The induced hypoxia could be blocked by HIF-1α gene silencing and reoxygenation of EMT in prostate cancer cells, hypoxia partially reversed accompanied by a process of mesenchymal-epithelial reverting transition (MErT). EMT might be induced by activation of HIF-1α-dependent cell signaling in hypoxic prostate cancer cells.

  7. YUCCA-mediated auxin biogenesis is required for cell fate transition occurring during de novo root organogenesis in Arabidopsis.

    Science.gov (United States)

    Chen, Lyuqin; Tong, Jianhua; Xiao, Langtao; Ruan, Ying; Liu, Jingchun; Zeng, Minhuan; Huang, Hai; Wang, Jia-Wei; Xu, Lin

    2016-07-01

    Many plant organs have the ability to regenerate a new plant after detachment or wounding via de novo organogenesis. During de novo root organogenesis from Arabidopsis thaliana leaf explants, endogenic auxin is essential for the fate transition of regeneration-competent cells to become root founder cells via activation of WUSCHEL-RELATED HOMEOBOX 11 (WOX11). However, the molecular events from leaf explant detachment to auxin-mediated cell fate transition are poorly understood. In this study, we used an assay to determine the concentration of indole-3-acetic acid (IAA) to provide direct evidence that auxin is produced after leaf explant detachment, a process that involves YUCCA (YUC)-mediated auxin biogenesis. Inhibition of YUC prevents expression of WOX11 and fate tra