6 research outputs found
Short Chain Chlorinated Paraffins in Mollusks from Coastal Waters in the Chinese Bohai Sea
As an extremely complex group of persistent organic pollutants
(POPs) candidates in the Stockholm Convention, short chain chlorinated
paraffins (SCCPs) have been of extensive concern in recent years.
In this study, nine bivalve and two gastropod species were collected
in 2009 to evaluate the spatial distributions and potential factors
influencing the bioaccumulation of SCCPs in mollusks in the Chinese
Bohai Sea. The concentrations of ∑ SCCPs in the mollusks were
in the range 64.9–5510 ng/g (dry weight) with an average chlorine
content of 61.1%. C<sub>10</sub> and C<sub>11</sub> were the predominant
homologue groups of SCCPs, which accounted for about 29.7% and 34.9%
of ∑ SCCPs, respectively. Six and seven chlorinated substituents
were the main congener groups. Mya arenaria (Mya), Mactra veneriformis (Mac),
and Crassostrea talienwhanensis (Oyster,
Ost) had higher average concentrations of SCCPs than other species,
implying that these bivalves could be used as sentinels to indicate
SCCPs contamination in this coastal region. A significant positive
linear relationship was found between SCCP concentrations and lipid
content of the mollusks, whereas the lipid-normalized SCCP concentrations
were negatively linear-related to the trophic levels (TL), which implied
that SCCPs did not show biomagnification in mollusks in this region
Tris(2,3-dibromopropyl) Isocyanurate, Hexabromocyclododecanes, and Polybrominated Diphenyl Ethers in Mollusks from Chinese Bohai Sea
A novel brominated flame retardant (BFR), trisÂ(2,3-dibromopropyl)
isocyanurate (TBC), as well as hexabromocyclododecanes (HBCDs) and
polybrominated diphenyl ethers (PBDEs), were analyzed in 11 species
of mollusks collected from nine coastal cities around the Chinese
Bohai Sea in 2009 and 2010. The detection frequencies were 100%, 99%,
and 77% for PBDEs, HBCDs, and TBC, respectively. Concentrations of
∑HBCDs ranged from below detection limit (nd) to 28.8 ng g<sup>–1</sup> on a dry weight (dw) basis, followed by ∑<sub>12</sub>PBDE (0.01–20.4 ng g<sup>–1</sup> dw) and TBC
(nd–12.1 ng g<sup>–1</sup> dw). Statistically significant
linear correlations were found among the three BFRs. Positive correlations
were found between BFRs concentrations and lipid content in mollusks.
The concentrations tend to decrease with increasing trophic levels
of the mollusks, implying trophic dilution rather than biomagnifications
of the BFRs in the aquatic food chains of the sampling area. Among
the 11 mollusks species, Mytilus edulis showed higher bioaccumulation capability than others and was therefore
considered to be an appropriate bioindicator of contamination by the
BFRs in the Chinese Bohai Sea, in agreement with its previous selection
for the biomonitoring of organochlorine pesticides (OCPs) and polychlorinated
biphenyls (PCBs). A dramatic decrease in PBDE concentrations in mollusks
of the area was found for the time period from 2003 to 2010, with
a half-life of only 2.3 ± 1.7 years, reflecting a rapid response
of mollusks to the change in pollution of the marine environment
Proteomic Comparison and MRM-Based Comparative Analysis of Metabolites Reveal Metabolic Shift in Human Prostate Cancer Cell Lines
One of the major
challenges in prostate cancer therapy remains
the development of effective treatments for castration-resistant prostate
cancer (CRPC), as the underlying mechanisms for its progression remain
elusive. Previous studies showed that androgen receptor (AR) is crucially
involved in regulation of metabolism in prostate cancer (PCa) cells
throughout the transition from early stage, androgen-sensitive PCa
to androgen-independent CRPC. AR achieves such metabolic rewiring
directively either via its transcriptional activity or via interactions
with AMP-activated protein kinase (AMPK). However, due to the heterogeneous
expression and activity status of AR in PCa cells, it remains a challenge
to investigate the links between AR status and metabolic alterations.
To this end, we compared the proteomes of three pairs of androgen-sensitive
(AS) and androgen-independent (AI) PCa cell lines, namely, PC3-AR<sup>+</sup>/PC3, 22Rv1/Du145, and LNCaP/C42B, using an iTRAQ labeling
approach. Our results revealed that most of the differentially expressed
proteins between each pair function in metabolism, indicating a metabolic
shift between AS and AI cells, as further validated by multiple reaction
monitoring (MRM)-based quantification of nucleotides and relative
comparison of fatty acids between these cell lines. Furthermore, increased
adenylate kinase isoenzyme 1 (AK1) in AS relative to AI cells may
result in activation of AMPK, representing a major regulatory factor
involved in the observed metabolic shift in PCa cells
Proteomic Comparison and MRM-Based Comparative Analysis of Metabolites Reveal Metabolic Shift in Human Prostate Cancer Cell Lines
One of the major
challenges in prostate cancer therapy remains
the development of effective treatments for castration-resistant prostate
cancer (CRPC), as the underlying mechanisms for its progression remain
elusive. Previous studies showed that androgen receptor (AR) is crucially
involved in regulation of metabolism in prostate cancer (PCa) cells
throughout the transition from early stage, androgen-sensitive PCa
to androgen-independent CRPC. AR achieves such metabolic rewiring
directively either via its transcriptional activity or via interactions
with AMP-activated protein kinase (AMPK). However, due to the heterogeneous
expression and activity status of AR in PCa cells, it remains a challenge
to investigate the links between AR status and metabolic alterations.
To this end, we compared the proteomes of three pairs of androgen-sensitive
(AS) and androgen-independent (AI) PCa cell lines, namely, PC3-AR<sup>+</sup>/PC3, 22Rv1/Du145, and LNCaP/C42B, using an iTRAQ labeling
approach. Our results revealed that most of the differentially expressed
proteins between each pair function in metabolism, indicating a metabolic
shift between AS and AI cells, as further validated by multiple reaction
monitoring (MRM)-based quantification of nucleotides and relative
comparison of fatty acids between these cell lines. Furthermore, increased
adenylate kinase isoenzyme 1 (AK1) in AS relative to AI cells may
result in activation of AMPK, representing a major regulatory factor
involved in the observed metabolic shift in PCa cells
Proteomic Comparison and MRM-Based Comparative Analysis of Metabolites Reveal Metabolic Shift in Human Prostate Cancer Cell Lines
One of the major
challenges in prostate cancer therapy remains
the development of effective treatments for castration-resistant prostate
cancer (CRPC), as the underlying mechanisms for its progression remain
elusive. Previous studies showed that androgen receptor (AR) is crucially
involved in regulation of metabolism in prostate cancer (PCa) cells
throughout the transition from early stage, androgen-sensitive PCa
to androgen-independent CRPC. AR achieves such metabolic rewiring
directively either via its transcriptional activity or via interactions
with AMP-activated protein kinase (AMPK). However, due to the heterogeneous
expression and activity status of AR in PCa cells, it remains a challenge
to investigate the links between AR status and metabolic alterations.
To this end, we compared the proteomes of three pairs of androgen-sensitive
(AS) and androgen-independent (AI) PCa cell lines, namely, PC3-AR<sup>+</sup>/PC3, 22Rv1/Du145, and LNCaP/C42B, using an iTRAQ labeling
approach. Our results revealed that most of the differentially expressed
proteins between each pair function in metabolism, indicating a metabolic
shift between AS and AI cells, as further validated by multiple reaction
monitoring (MRM)-based quantification of nucleotides and relative
comparison of fatty acids between these cell lines. Furthermore, increased
adenylate kinase isoenzyme 1 (AK1) in AS relative to AI cells may
result in activation of AMPK, representing a major regulatory factor
involved in the observed metabolic shift in PCa cells
Identification of Tetrabromobisphenol A Allyl Ether and Tetrabromobisphenol A 2,3-Dibromopropyl Ether in the Ambient Environment near a Manufacturing Site and in Mollusks at a Coastal Region
Tetrabromobisphenol A (TBBPA) is
one of the most widely used brominated
flame retardants (BFRs) and has been frequently detected in the environment
and biota. Recent studies have found that derivatives of TBBPA, such
as TBBPA bisÂ(allyl) ether (TBBPA BAE) and TBBPA bisÂ(2,3-dibromopropyl)
ether (TBBPA BDBPE) are present in various environmental compartments.
In this work, using liquid chromatography coupled with tandem mass
spectrometry (LC–MS/MS) and liquid chromatography coupled with
quadrupole time-of-flight mass spectrometry (LC–Q-TOF-MS),
TBBPA allyl ether (TBBPA AE) and TBBPA 2,3-dibromopropyl ether (TBBPA
DBPE) were identified in environmental samples and further confirmed
by synthesized standards. Soil, sediment, rice hull, and earthworm
samples collected near a BFR manufacturing plant were found to contain
these two compounds. In sediments, the concentrations of TBBPA AE
and TBBPA DBPE ranged from 1.0 to 346.6 ng/g of dry weight (dw) and
from 0.7 to 292.7 ng/g of dw, respectively. TBBPA AE and TBBPA DBPE
in earthworm and rice hull samples were similar to soil samples, which
ranged from below the method limit of detection (LOD, <0.002 ng/g
of dw) to 0.064 ng/g of dw and from below the LOD (<0.008 ng/g
of dw) to 0.58 ng/g of dw, respectively. Furthermore, mollusks collected
from the Chinese Bohai Sea were used as a bioindicator to investigate
the occurrence and distribution of these compounds in the coastal
environment. The detection frequencies of TBBPA AE and TBBPA DBPE
were 41 and 32%, respectively, and the concentrations ranged from
below LOD (<0.003 ng/g of dw) to 0.54 ng/g of dw, with an average
of 0.09 ng/g of dw, for TBBPA AE, and from below LOD (<0.008 ng/g
of dw) to 1.41 ng/g of dw, with an average of 0.15 ng/g of dw, for
TBBPA DBPE