473,274 research outputs found
Transforming growth factor beta(1) selectively regulates ferritin gene expression in malignant H-ras-transformed fibrosarcoma cell lines
No full textTransforming growth factor beta(1) is an important growth regulator in many cell types, usually exerting a negative effect on cellular growth. Inhibition of DNA synthesis and cell proliferation is frequently lost during malignant transformation, and in some cases, tumor cell proliferation is actually stimulated by TGF-beta(1). The present study demonstrates a novel link between alterations in TGF-beta(1), regulation during malignant conversion, and the expression of ferritin, an important activity involved in a number of biological functions including iron homeostasis and cell-growth control. A series of H-ras-transformed mouse 10 T 1/2 cell lines, exhibiting increasing malignant potential, was investigated for possible TGF-beta(1)-mediated changes in ferritin gene expression. Selective induction of gene expression was observed, since only H-ras-transformed cells with malignant potential exhibited marked elevations in ferritin gene expression, in particular, alterations in H-ferritin gene expression. The regulation of H-ferritin gene expression in response to TGF-beta(1) did not involve alterations in transcription, but occurred through mechanisms of post-transcriptional stabilization of the H-ferritin mRNA. Additionally, evidence was obtained for a cycloheximide-sensitive regulator of H-ferritin gene expression, since the presence of this protein synthesis inhibitor increased H-ferritin message levels, and in combination with TGF-beta(1), cooperated in an additive manner to augment H-ferritin gene expression. These results show for the first time that TGF-beta(1) can regulate ferritin gene expression in malignant H-ras transformed cells, and suggest a mechanism for growth factor stimulation of malignant cells, in which early alterations in the control of H-ferritin gene expression are important.PT: J; CR: AMARA FM, 1993, NUCLEIC ACIDS RES, V21, P4803 AMARA FM, 1994, J BIOL CHEM, V269, P6707 CHOY BK, 1989, BIOCHEM BIOPH RES CO, V162, P1412 DESHPANDE VV, 1985, J BIOL CHEM, V260, P757 EDWARDS DR, 1992, EMBO J, V11, P2415 EGAN SE, 1987, MOL CELL BIOL, V7, P830 EGAN SE, 1987, SCIENCE, V238, P202 EGAN SE, 1988, CELLULAR MOL BIOL TU, P279 GONZALEZ IL, 1985, P NATL ACAD SCI USA, V82, P7666 GREENBERG AH, 1989, INVAS METAST, V9, P360 HURTA RAR, 1990, BIOCHIM BIOPHYS ACTA, V1087, P165 HURTA RAR, 1991, BIOCHEM CELL BIOL, V69, P635 HURTA RAR, 1991, J BIOL CHEM, V266, P24097 HURTA RAR, 1992, J BIOL CHEM, V267, P7066 HURTA RAR, 1993, J CELL PHYSIOL, V156, P272 HURTA RAR, 1995, J CELL BIOCHEM, V57, P543 JAKOWLEW SB, 1988, ONCOGENE RES, V2, P135 KOHGO Y, 1980, J BIOL CHEM, V255, P5195 LEIBOLD EA, 1984, J BIOL CHEM, V259, P4327 MATTIA E, 1989, P NATL ACAD SCI USA, V86, P1801 MCCLARTY GA, 1987, BIOCHEMISTRY-US, V26, P8004 MCCLARTY GA, 1990, J BIOL CHEM, V265, P7539 MILLER LL, 1991, P NATL ACAD SCI USA, V88, P4946 MUKHERJEE R, 1987, J BIOL CHEM, V262, P13697 MURRAY MT, 1987, P NATL ACAD SCI USA, V84, P7438 NICOLSON GL, 1984, CANCER METAST REV, V3, P25 PANG JHS, 1996, BIOCHEM J 1, V319, P185 PERTOVAARA L, 1989, MOL CELL BIOL, V9, P1255 PHILLIPS DR, 1986, BIOCHEMISTRY-US, V25, P7355 RAGHOW R, 1987, TRENDS BIOCHEM SCI, V12, P358 SCHWARZ LC, 1988, CANCER RES, V48, P6999 SCHWARZ LC, 1990, GROWTH FACTORS, V3, P115 SPORN MB, 1990, CELL REGUL, V1, P875 TAMBURINI A, 1999, UNPUB TRANSFORMATION TAMM I, 1978, ADV VIRUS RES, V22, P187 THEIL EC, 1987, ANNU REV BIOCHEM, V56, P289 THELANDER L, 1980, J BIOL CHEM, V255, P7426 THOMAS CE, 1986, J BIOL CHEM, V261, P13064 WEBER G, 1983, CANCER RES, V43, P3466 WEINBERG RA, 1989, ONCOGENES MOL ORIGIN, P46 WILDER PJ, 1991, CANCER RES, V51, P5898 WRIGHT JA, 1989, INT ENCY PHARM THERA, V128, P89 WRIGHT JA, 1990, ANTICANCER RES, V10, P1247 WRIGHT JA, 1990, BIOCH CELL BIOL, V68, P1364 WRIGHT JA, 1993, CRIT REV ONCOGENESIS, V4, P473; NR: 45; TC: 1; J9: BIOCHEM CELL BIOL; PG: 9; GA: 356BNSource type: Electronic(1
Monazite dissolution-reprecipitation in medium-grade metasedimentary rocks from the Northern Apennines, Italy.
No full textFluid-induced dissolution of parent phases and precipitation of products is a fundamental process in metamorphism
(Putnis & Austrheim, 2010). Here we present the dissolution-reprecipitation behaviour of monazite, one of the main
rare-earth element (REE)-bearing accessory minerals useful for obtaining geochronological and geochemical
information from a wide range of Ca-poor crustal rocks. The reactions involving monazite were studied in a micaschist
recovered from the Pontremoli 1 well (Tuscany) and the implications of fluid-controlled monazite breakdown on age
dating were discussed (Lo Pò et al., 2016). The micaschist belongs to the Variscan basement of the Northern Apennines.
In this rock monazite, either disseminated in the matrix or included in white mica and chlorite partially replacing garnet,
is surrounded by coronitic microstructures consisting of concentric shells of apatite + Th-silicate, allanite, epidote.
Studies of the element partitioning between garnet and accessory minerals and the garnet inclusion mineralogy suggest
that monazite was partially dissolved and replaced by apatite, allanite and epidote during garnet breakdown to chlorite
and muscovite. This stage was associated with the retrograde and decompressional evolution of the micaschist at fluid-
present conditions. Through thermodynamic modelling, we determined the P-T conditions of the monazite partial
dissolution and replacement process at 510 ± 35°C, during a nearly isothermal decompression path from 8 kbar to 2-3
kbar. Fluid-induced alteration of monazite also resulted in a partial resetting of the monazite ages, which were
determined to be between 294 and 19 Ma. The maximum extent of the alteration process occurred in monazite located
within retrogressed garnet rims. In this microstructural site, Pb in the Variscan monazite was lost.
Lo Pò, D., Braga, R., Massonne, H.-J., Molli, G., Montanini, A., Theye, T. (2016): Fluid-induced breakdown of monazite in medium-
grade metasedimentary rocks of the Pontremoli basement (Northern Apennines, Italy). J. Metamorph. Geol., 34, 63-84.
Putnis, A. & Austrheim, H. (2010): Fluid-induced processes: metasomatism and metamorphism. Geofluids, 10, 254-269
Monazite dissolution-reprecipitation in medium-grade metasedimentary rocks from the northern Apennines, Italy
No full textFluid-induced dissolution of parent phases and precipitation of products is a fundamental process in metamorphism
(Putnis & Austrheim, 2010). Here we present the dissolution-reprecipitation behaviour of monazite, one of the main
rare-earth element (REE)-bearing accessory minerals useful for obtaining geochronological and geochemical
information from a wide range of Ca-poor crustal rocks. The reactions involving monazite were studied in a micaschist
recovered from the Pontremoli 1 well (Tuscany) and the implications of fluid-controlled monazite breakdown on age
dating were discussed (Lo Pò et al., 2016). The micaschist belongs to the Variscan basement of the Northern Apennines.
In this rock monazite, either disseminated in the matrix or included in white mica and chlorite partially replacing garnet,
is surrounded by coronitic microstructures consisting of concentric shells of apatite + Th-silicate, allanite, epidote.
Studies of the element partitioning between garnet and accessory minerals and the garnet inclusion mineralogy suggest
that monazite was partially dissolved and replaced by apatite, allanite and epidote during garnet breakdown to chlorite
and muscovite. This stage was associated with the retrograde and decompressional evolution of the micaschist at fluidpresent
conditions. Through thermodynamic modelling, we determined the P-T conditions of the monazite partial
dissolution and replacement process at 510 ± 35°C, during a nearly isothermal decompression path from 8 kbar to 2-3
kbar. Fluid-induced alteration of monazite also resulted in a partial resetting of the monazite ages, which were
determined to be between 294 and 19 Ma. The maximum extent of the alteration process occurred in monazite located
within retrogressed garnet rims. In this microstructural site, Pb in the Variscan monazite was lost.
Lo Pò, D., Braga, R., Massonne, H.-J., Molli, G., Montanini, A., Theye, T. (2016): Fluid-induced breakdown of monazite in mediumgrade
metasedimentary rocks of the Pontremoli basement (Northern Apennines, Italy). J. Metamorph. Geol., 34, 63-84.
Putnis, A. & Austrheim, H. (2010): Fluid-induced processes: metasomatism and metamorphism. Geofluids, 10, 254-269
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
[Report to Chief J. E. Curry, by an unknown author #1]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
[Report to Chief J. E. Curry, by an unknown author #2]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
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