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991.
The green tea compound, (-)-epigallocatechin-3-gallate downregulates N-cadherin and suppresses migration of bladder carcinoma cells 总被引:1,自引:0,他引:1
Rieger-Christ KM Hanley R Lodowsky C Bernier T Vemulapalli P Roth M Kim J Yee AS Le SM Marie PJ Libertino JA Summerhayes IC 《Journal of cellular biochemistry》2007,102(2):377-388
Green tea has been reported as potential dietary protection against numerous cancers and has been shown to have activity in bladder tumor inhibition in different animal models. The goal of this study was to examine the effects of (-)-epigallocatechin gallate (EGCG-the major phytochemical in green tea) on growth inhibition and behavior of human bladder carcinoma cells and to identify the altered signaling pathway(s) underlying the response to EGCG exposure. EGCG inhibited the in vitro growth of invasive bladder carcinoma cells with an IC(50) range of 70-87 microM. At a concentration of 20 microM, EGCG decreased the migratory potential of bladder carcinoma cells with concomitant activation of p42/44 MAPK and STAT3 and inactivation of Akt. Using biochemical inhibitors of MAPK/ERK, and siRNA to knockdown STAT3 and Akt, inhibition of migration was recorded associated with Akt but not MAPK/ERK or STAT3 signaling in bladder cells. In addition, EGCG downregulated N-cadherin in a dose-dependent manner where reduction in N-cadherin expression paralleled declining migratory potential. Continuous feeding of EGCG to mice prior to and during the establishment of bladder carcinoma xenografts in vivo revealed >50% reduction in mean final tumor volume (P = 0.05) with no detectable toxicity. EGCG inhibited bladder carcinoma cell growth and suppressed the in vitro migration capacity of cells via downregulation of N-cadherin and inactivation of Akt signaling. Continuous administration of EGCG to mice revealed significant inhibition of tumor growth in vivo indicating a possible preventative role for green tea in bladder cancer. 相似文献
992.
Three juvenile narwhals captured during August 1998 in the northeast of Svalbard, Norway, were equipped with satellite-relayed
data loggers (SRDLs) that transmitted diving and swim-speed data, in addition to location, for up to 46 days. A total of 1,354
complete dive cycles were recorded. Most of the diving was shallow and of short duration. Maximum recorded dive depth was
546 m, maximum recorded dive duration was 24.8 min, and maximum recorded swim-speed was 4.7 ms−1. Ascent speed, vertical ascent speed, descent speed and vertical descent speed were all significantly higher during deep
dives (>200 m) than for shallow dives (<200 m). In addition both ascent and descent angles were much steeper for deep dives
than during shallow dives. Most of the shallow diving seemed to be associated with travelling, with the animal shifting between
various locations, while the deep diving (often to the bottom) for extended periods in some specific areas might have been
associated with foraging. Even though the sample size in this study is small, the data are the first information available
for movements and diving behaviour of narwhals near Svalbard. 相似文献
993.
994.
CETACEAN OCCURRENCE PATTERNS IN THE AMUNDSEN AND SOUTHERN BELLINGSHAUSEN SEA SECTOR, SOUTHERN OCEAN 总被引:1,自引:0,他引:1
David G. Ainley Katie M. Dugger † Viola Toniolo ‡ Ian Gaffney § 《Marine Mammal Science》2007,23(2):287-305
We conducted 239.5 h and 3,494 km of cetacean surveys in the Amundsen and Bellingshausen seas, from 15 February to 31 March 1994; most of the area, the large portion of which was ice covered, had never before nor has it since been surveyed for cetaceans, even to the date when this paper was prepared (2006). Logistic regression and an information-theoretic approach related the occurrence of Antarctic minke whales Balaenoptera bonaerensis (the most abundant species) to whether we were in open- or pack-ice-covered pelagic or neritic waters, in or out of the marginal ice zone (MIZ), and north or south of the Antarctic Circumpolar Current southern boundary. Other variables included date and distance to the MIZ and shelfbreak front. Statistical analysis showed that the probability of sighting a minke, as well as killer whale—but not the case for an index to whale density—was related to the proximity of coastal polynyas in early autumn, switching offshore to the MIZ once waters within the pack began to freeze persistently later in the season. Probability of detection was higher with distance into the MIZ. Supporting these findings, the density index was strongly related to ice concentration in an inverse relationship. The strong relationship to polynyas and the MIZ indicate that sea-ice divergence altered by decadal or longer-term climate change, as described in the recent literature, could well affect any apparent, long-term trends evident in this species' abundance if surveyed only in open or near-to-ice waters. We speculate on how the minke whale's pagophilic nature (1) could have been encouraged by large-scale industrial whaling and by competition with species more characteristic of open waters and the outer MIZ, and (2) may have protected the population somewhat during industrial whaling resulting in the much greater abundance of this species now compared to other targeted species. 相似文献
995.
Lamesch P Li N Milstein S Fan C Hao T Szabo G Hu Z Venkatesan K Bethel G Martin P Rogers J Lawlor S McLaren S Dricot A Borick H Cusick ME Vandenhaute J Dunham I Hill DE Vidal M 《Genomics》2007,89(3):307-315
Complete sets of cloned protein-encoding open reading frames (ORFs), or ORFeomes, are essential tools for large-scale proteomics and systems biology studies. Here we describe human ORFeome version 3.1 (hORFeome v3.1), currently the largest publicly available resource of full-length human ORFs (available at ). Generated by Gateway recombinational cloning, this collection contains 12,212 ORFs, representing 10,214 human genes, and corresponds to a 51% expansion of the original hORFeome v1.1. An online human ORFeome database, hORFDB, was built and serves as the central repository for all cloned human ORFs (http://horfdb.dfci.harvard.edu). This expansion of the original ORFeome resource greatly increases the potential experimental search space for large-scale proteomics studies, which will lead to the generation of more comprehensive datasets. 相似文献
996.
997.
Crystal structure of a transcription regulator (TM1602) from Thermotoga maritima at 2.3 A resolution
Weekes D Miller MD Krishna SS McMullan D McPhillips TM Acosta C Canaves JM Elsliger MA Floyd R Grzechnik SK Jaroszewski L Klock HE Koesema E Kovarik JS Kreusch A Morse AT Quijano K Spraggon G van den Bedem H Wolf G Hodgson KO Wooley J Deacon AM Godzik A Lesley SA Wilson IA 《Proteins》2007,67(1):247-252
998.
Krishna SS Tautz L Xu Q McMullan D Miller MD Abdubek P Ambing E Astakhova T Axelrod HL Carlton D Chiu HJ Clayton T DiDonato M Duan L Elsliger MA Grzechnik SK Hale J Hampton E Han GW Haugen J Jaroszewski L Jin KK Klock HE Knuth MW Koesema E Morse AT Mustelin T Nigoghossian E Oommachen S Reyes R Rife CL van den Bedem H Weekes D White A Hodgson KO Wooley J Deacon AM Godzik A Lesley SA Wilson IA 《Proteins》2007,69(2):415-421
999.
Kindt KS Quast KB Giles AC De S Hendrey D Nicastro I Rankin CH Schafer WR 《Neuron》2007,55(4):662-676
Dopamine has been implicated in the modulation of diverse forms of behavioral plasticity, including appetitive learning and addiction. An important challenge is to understand how dopamine's effects at the cellular level alter the properties of neural circuits to modify behavior. In the nematode C. elegans, dopamine modulates habituation of an escape reflex triggered by body touch. In the absence of food, animals habituate more rapidly than in the presence of food; this contextual information about food availability is provided by dopaminergic mechanosensory neurons that sense the presence of bacteria. We find that dopamine alters habituation kinetics by selectively modulating the touch responses of the anterior-body mechanoreceptors; this modulation involves a D1-like dopamine receptor, a Gq/PLC-beta signaling pathway, and calcium release within the touch neurons. Interestingly, the body touch mechanoreceptors can themselves excite the dopamine neurons, forming a positive feedback loop capable of integrating context and experience to modulate mechanosensory attention. 相似文献
1000.
Véronique Breguet Raphaël Gugerli Urs von Stockar Ian William Marison 《Cytotechnology》2007,53(1-3):81-93
Microencapsulation offers a unique potential for high cell density, high productivity mammalian cell cultures. However, for
successful exploitation there is the need for microcapsules of defined size, properties and mechanical stability. Four types
of alginate/poly-l-Lysine microcapsules, containing recombinant CHO cells, have been investigated: (a) 800 μm liquid core microcapsules, (b)
500 μm liquid core microcapsules, (c) 880 μm liquid core microcapsules with a double PLL membrane and (d) 740 μm semi-liquid
core microcapsules. With encapsulated cells a reduced growth rate was observed, however this was accompanied by a 2–3 fold
higher specific production rate of the recombinant protein. Interestingly, the maximal intracapsular cell concentration was
only 8.7 × 107 cell mL-1, corresponding to a colonization of 20% of the microcapsule volume. The low level of colonization is unlikely to be due to
diffusional limitations since reduction of microcapsule size had no effect. Measurement of cell leaching and mechanical properties
showed that liquid core microcapsules are not suitable for continuous long-term cultures (>1 month). By contrast semi-liquid
core microcapsules were stable over long periods with a constant level of cell colonization (ϕ = 3%). This indicates that
the alginate in the core plays a predominant role in determining the level of microcapsule colonization. This was confirmed
by experiments showing reduced growth rates of batch suspension cultures of CHO cells in medium containing dissolved alginate.
Removal of this alginate would therefore be expected to increase microcapsule colonization. 相似文献