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Micro- and macroplastic accumulation in a newly formed Spartina alterniflora colonized estuarine saltmarsh in southeast China
In recent years, there is great concern about plastic pollution due to the identification of several environmental risks associated with microplastics (<5 mm). This study investigated microplastic and macroplastic accumulation patterns in a newly formed Spartina alterniflora colonized saltmarsh of an estuary in southeastern China. Abundance of microplastic and macroplastic particles was in the range of 9600â130725 and 200-4350 n/m2, respectively. Abundances of microplastics and macroplastics were highest at the saltmarsh edge, but the mass of macroplastics was highest in the saltmarsh interior. Mass of microplastics and macroplastics in bareflats was significantly lower than vegetated areas. Although microplastics accounted for 96.3% of total plastic abundance, macroplastics accounted for 90% of total plastic mass. Results showed that S. alterniflora dominated saltmarshes have a strong ability to trap plastic debris, especially macroplastics. Thus, coastal saltmarshes may serve as a transformer of macroplastics to microplastics and consequently as a source of microplastics to the ocean
An In Vivo Screen Identifies PYGO2 as a Driver for Metastatic Prostate Cancer
Advanced prostate cancer displays conspicuous chromosomal instability and rampant copy number aberrations, yet the identity of functional drivers resident in many amplicons remain elusive. Here, we implemented a functional genomics approach to identify new oncogenes involved in prostate cancer progression. Through integrated analyses of focal amplicons in large prostate cancer genomic and transcriptomic datasets as well as genes upregulated in metastasis, 276 putative oncogenes were enlisted into an in vivo gain-of-function tumorigenesis screen. Among the top positive hits, we conducted an in-depth functional analysis on Pygopus family PHD finger 2 (PYGO2), located in the amplicon at 1q21.3. PYGO2 overexpression enhances primary tumor growth and local invasion to draining lymph nodes. Conversely, PYGO2 depletion inhibits prostate cancer cell invasion in vitro and progression of primary tumor and metastasis in vivo In clinical samples, PYGO2 upregulation associated with higher Gleason score and metastasis to lymph nodes and bone. Silencing PYGO2 expression in patient-derived xenograft models impairs tumor progression. Finally, PYGO2 is necessary to enhance the transcriptional activation in response to ligand-induced Wnt/ÎČ-catenin signaling. Together, our results indicate that PYGO2 functions as a driver oncogene in the 1q21.3 amplicon and may serve as a potential prognostic biomarker and therapeutic target for metastatic prostate cancer.Significance: Amplification/overexpression of PYGO2 may serve as a biomarker for prostate cancer progression and metastasis. Cancer Res; 78(14); 3823-33. ©2018 AACR
CHIP promotes Runx2 degradation and negatively regulates osteoblast differentiation
Runx2, an essential transactivator for osteoblast differentiation, is tightly regulated at both the transcriptional and posttranslational levels. In this paper, we report that CHIP (C terminus of Hsc70-interacting protein)/STUB1 regulates Runx2 protein stability via a ubiquitination-degradation mechanism. CHIP interacts with Runx2 in vitro and in vivo. In the presence of increased Runx2 protein levels, CHIP expression decreases, whereas the expression of other E3 ligases involved in Runx2 degradation, such as Smurf1 or WWP1, remains constant or increases during osteoblast differentiation. Depletion of CHIP results in the stabilization of Runx2, enhances Runx2-mediated transcriptional activation, and promotes osteoblast differentiation in primary calvarial cells. In contrast, CHIP overexpression in preosteoblasts causes Runx2 degradation, inhibits osteoblast differentiation, and instead enhances adipogenesis. Our data suggest that negative regulation of the Runx2 protein by CHIP is critical in the commitment of precursor cells to differentiate into the osteoblast lineage
Understanding the and with Sum Rules in HQET
In the framework of heavy quark effective theory we use QCD sum rules to
calculate the masses of the and excited
states. The results are consistent with that the states and
observed by BABAR and CLEO are the and states in the
doublet
A search for pre-substellar cores and proto-brown dwarf candidates in Taurus: multiwavelength analysis in the B213-L1495 clouds
In an attempt to study whether the formation of brown dwarfs (BDs) takes
place as a scaled-down version of low-mass stars, we conducted IRAM30m/MAMBO-II
observations at 1.2 mm in a sample of 12 proto-BD candidates selected from
Spitzer/IRAC data in the B213-L1495 clouds in Taurus. Subsequent observations
with the CSO at 350 micron, VLA at 3.6 and 6 cm, and IRAM30m/EMIR in the
12CO(1-0), 13CO(1-0), and N2H+(1-0) transitions were carried out toward the two
most promising Spitzer/IRAC source(s), J042118 and J041757. J042118 is
associated with a compact (<10 arcsec or <1400 AU) and faint source at 350
micron, while J041757 is associated with a partially resolved (~16 arcsec or
~2000 AU) and stronger source emitting at centimetre wavelengths with a flat
spectral index. The corresponding masses of the dust condensations are ~1 and
~5 Mjup for J042118 and J041757, respectively. In addition, about 40 arcsec to
the northeast of J041757 we detect a strong and extended submillimetre source,
J041757-NE, which is not associated with NIR/FIR emission down to our detection
limits, but is clearly detected in 13CO and N2H+ at ~7 km/s, and for which we
estimated a total mass of ~100 Mjup, close to the mass required to be
gravitationally bound. In summary, our observational strategy has allowed us to
find in B213-L1495 two proto-BD candidates and one pre-substellar core
candidate, whose properties seem to be consistent with a scaled-down version of
low-mass stars.Comment: MNRAS, 424, 2778; corrected typos, mass estimate refined in Section
3.2.1 and Section 5.3; conclusions unchange
Modelling Herschel observations of hot molecular gas emission from embedded low-mass protostars
Aims. Young stars interact vigorously with their surroundings, as evident
from the highly rotationally excited CO (up to Eup=4000 K) and H2O emission (up
to 600 K) detected by the Herschel Space Observatory in embedded low-mass
protostars. Our aim is to construct a model that reproduces the observations
quantitatively, to investigate the origin of the emission, and to use the lines
as probes of the various heating mechanisms.
Methods. The model consists of a spherical envelope with a bipolar outflow
cavity. Three heating mechanisms are considered: passive heating by the
protostellar luminosity, UV irradiation of the outflow cavity walls, and C-type
shocks along the cavity walls. Line fluxes are calculated for CO and H2O and
compared to Herschel data and complementary ground-based data for the
protostars NGC1333 IRAS2A, HH 46 and DK Cha. The three sources are selected to
span a range of evolutionary phases and physical characteristics.
Results. The passively heated gas in the envelope accounts for 3-10% of the
CO luminosity summed over all rotational lines up to J=40-39; it is best probed
by low-J CO isotopologue lines such as C18O 2-1 and 3-2. The UV-heated gas and
the C-type shocks, probed by 12CO 10-9 and higher-J lines, contribute 20-80%
each. The model fits show a tentative evolutionary trend: the CO emission is
dominated by shocks in the youngest source and by UV-heated gas in the oldest
one. This trend is mainly driven by the lower envelope density in more evolved
sources. The total H2O line luminosity in all cases is dominated by shocks
(>99%). The exact percentages for both species are uncertain by at least a
factor of 2 due to uncertainties in the gas temperature as function of the
incident UV flux. However, on a qualitative level, both UV-heated gas and
C-type shocks are needed to reproduce the emission in far-infrared rotational
lines of CO and H2O.Comment: 15 pages (+4 pages appendix), 20 figures, accepted by A&
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