Sediment has been considered as an important sink for microplastics (MPs), but there are limited reports about the spatial and temporal variability of MPs in sediment from the Arctic Ocean. ...Furthermore, understanding is lacking on the correlation between Arctic sea ice variation and MP abundance in sediment. This study aimed to assess the MP contamination in the sediment from the Chukchi Sea over five years through three voyages (in 2016, 2018, and 2020). The MP abundances in the sediments from the Chukchi Plateau and Chukchi Shelf over five years ranged from 33.66 ± 15.08 to 104.54 ± 28.07 items kg-1 dry weight (DW) and 20.63 ± 6.71 to 55.64 ± 22.61 items kg-1 DW, respectively. The MP levels from the Chukchi Sea were lower than those from the Eastern Arctic Ocean. Our findings suggest that the Chukchi Plateau is an accumulation zone for fibers related to fishing gear and textiles under the dual influence of the Pacific and Atlantic Ocean currents. However, the reduction of these fibers in the sediment from the Chukchi Shelf might be related to bottom currents, sediment resuspension, and biomass. Moreover, the MP abundance in the sediment from the Chukchi Sea was positively correlated with the reduction of Arctic sea ice, suggesting that the melting sea ice contributes to the increase in MP levels in the sediment. The increase in blue MPs from the Chukchi Plateau over time might be attributed to melting sea ice or intense fishing activity, whereas the increase of the smallest MPs in this region could be owing to the breakdown of larger plastics during long-distance transport or the easier settlement of smaller MPs. Further time-series investigations are urgently required to improve the understanding of the environmental fate and transport of MPs among the different Arctic environmental compartments.
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•MP abundance in the sediment from Chukchi Plateau exhibited an increasing trend.•The Chukchi Plateau is a hotspot for MPs related to fishing gear and textiles.•The receding sea ice in the Chukchi Sea promoted the increase in sedimentary MPs.•Blue and smaller MPs increased in the sediment from the Chukchi Plateau.•Chukchi Shelf might be a source of some engineering-and industry-related MPs.
Polycomb repressive complex 1 (PRC1) plays essential roles in cell fate decisions and development. However, its role in cancer is less well understood. Here, we show that RNF2, encoding RING1B, and ...canonical PRC1 (cPRC1) genes are overexpressed in breast cancer. We find that cPRC1 complexes functionally associate with ERα and its pioneer factor FOXA1 in ER+ breast cancer cells, and with BRD4 in triple-negative breast cancer cells (TNBC). While cPRC1 still exerts its repressive function, it is also recruited to oncogenic active enhancers. RING1B regulates enhancer activity and gene transcription not only by promoting the expression of oncogenes but also by regulating chromatin accessibility. Functionally, RING1B plays a divergent role in ER+ and TNBC metastasis. Finally, we show that concomitant recruitment of RING1B to active enhancers occurs across multiple cancers, highlighting an under-explored function of cPRC1 in regulating oncogenic transcriptional programs in cancer.
Acute lung injury (ALI) remains a significant global health issue, necessitating novel therapeutic interventions. In our latest study, we pioneered the use of D-mannitol–cerium–quercetin/rutin ...coordination polymer nanoparticles (MCQ/R NPs) as a potential treatment for ALI. The MCQ/R NPs, which integrate rutin and quercetin for their therapeutic potential and D-mannitol for its pulmonary targeting, displayed exceptional efficacy. By utilizing cerium ions for optimal nanoparticle assembly, the MCQ/R NPs demonstrated an average size of less than 160 nm. Impressively, these nanoparticles outperformed conventional treatments in both antioxidative capabilities and biocompatibility. Moreover, our in vivo studies on LPS-induced ALI mice showed a significant reduction in lung tissue inflammation. This groundbreaking research presents MCQ/R NPs as a promising new approach in ALI therapeutics.
Di-2-ethylhexyl phthalate (DEHP) harms mammalian testis development, yet the specific mechanism of its effect on sperm quality and function is unclear. In this study, male mice were administrated ...DEHP (200 mg/kg/day) via intragastric (i.g.) injection for 35 days. The sperm quality and function of DEHP-exposed mice were evaluated. DEHP exposure reduced the relative testis weight and serum testosterone levels. In addition, sperm count and motility parameters decreased significantly, which led to reduced sperm fertility characterized by reduced acrosome reaction rate, sperm-egg binding capacity and blastocyte formation. DEHP exposure decreased anti-oxidant indicators and the expressions of Cat, Sod1, Prdx6 and Sirt1 in the testis. DEHP-exposure also resulted in decreased proliferating cell nuclear antigen (PCNA) expression in mice testis, as well as the dose-dependent inhibition of the proliferation of GC-1 and GC-2 cells. These phenotypes may be related to increased cell apoptosis characterized by BAX/BCL2 and P53 up-regulation. DEHP exposure resulted in the down-regulation of SIRT1 and p-AKT in mice testis and decreased levels of GC-1and GC-2 cells. DEHP co-incubation with sperm in vitro resulted in decreased tyrosine phosphorylation and progressive motility, as well as p-AKT expression in capacitated sperm. Differential sperm proteomics identified 495 differentially expressed proteins, including 257 proteins down-regulated in the DEHP-exposure group. Bioinformatics analysis showed that proteins involved in sperm-egg interaction and fertilization processes were significantly down-regulated. Pathway analysis demonstrated that the adhesion pathway was enriched in down-regulated proteins, while the pathway associated with ribosomes was enriched in up-regulated proteins. Conclusively, DEHP exposure impaired male fertility by affecting sperm quality and function, and a pathway mediating the DEHP-induced decline in sperm quality and function was identified. The study provides additional information for understanding the molecular mechanisms of DEHP exposure and its effects on male reproduction.
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•DEHP exposure affected mice spermatogenesis.•DEHP exposure induced sperm quality and function defects in mice.•AKT/SIRT1 pathway was associated with testis damages induced by DEHP.•DEHP exposure reduced mice sperm-egg binding capacity.
The effect of fretting frequency on fretting corrosion behavior between Alloy 690TT heat-exchanger tube and 405 stainless steel plate in simulated secondary water of pressurized water reactor nuclear ...power plants was investigated. The wear volume and wear coefficient of 690TT tube increased initially and then decreased with increasing frequency, while wear volume and wear coefficient of corresponding 405 SS plate gradually increased. The mechanisms of friction and wear were analyzed in detail. The friction coefficient and the total dissipated energy deceased with increasing frequency, which is related to crack initiation and propagation. Moreover, wear mechanism changed from abrasive wear to oxidative wear and delamination as the stress increased. Finally, a predictive model of service life of 690TT tube was proposed.
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•Wear scar profile of 690TT tube is in “W” shape while it is in “U” shape for 405 SS plate.•Wear volume of 690 TT tube increases initially and then decreases with the increasing of frequency.•The main wear mechanism is affected by the local stress distribution.•An assessment model is proposed to predict the service life of 690TT tube in fretting process.
We present four designs of tunable split-disk metamaterial (SDM) absorbers. They consist of a bottom gold (Au) mirror layer anchored on Si substrate and a suspended-top SDM nanostructure with one, ...two, three, and four splits named SDM-1, SDM-2, SDM-3, and SDM-4, respectively. By tailoring the geometrical configurations, the four SDMs exhibit different tunable absorption resonances spanning from 1.5 µm to 5.0 µm wavelength range. The resonances of absorption spectra can be tuned in the range of 320 nm, and the absorption intensities become lower by increasing the gaps of the air insulator layer. To increase the sensitivity of the proposed devices, SDMs exhibit high sensitivities of 3312 nm/RIU (refractive index unit, RIU), 3362 nm/RIU, 3342 nm/RIU, and 3567 nm/RIU for SDM-1, SDM-2, SDM-3, and SDM-4, respectively. The highest correlation coefficient is 0.99999. This study paves the way to the possibility of optical gas sensors and biosensors with high sensitivity.
Bisphenol A (BPA) exposure is known to cause damage to male fertility. Conversely, melatonin (MLT) has been shown to offer protection against reproductive damage by acting as an antioxidant. ...Exploration into the molecular mechanisms behind how MLT alleviates BPA-induced male fertility damage remains unclear. In this study, adult male mice were divided into four groups of control, BPA exposure (intragastrically, 50 mg/kg/day), MLT treatment (intraperitoneal injection, 10 mg/kg/day) and combined BPA+MLT treatment group for comparative analysis after five weeks of treatment. BPA exposure led to male mice subfertility characterized by poor sperm quality of decreased sperm counts and motility, and reduced pregnancy rate of female mice in in vivo and blastocyst formation in vitro experiments. In BPA exposed mice, germ cell proliferation was impaired, showing a decrease in PCNA expression. BPA exposure also induced a decrease in the expression of antioxidant molecules Cat, Prdx6, and Sod1, and up-regulated BAX expression. These expression changes resulted in increased germ cell apoptosis detected by TUNEL experiments. MLT treatment significantly maintained male mice sperm quality and fertility adversely affected by BPA through modulating the abovementioned responses. Sperm proteomics identified 118 BPA-regulated proteins whose expression was changed by MLT treatment, including 37 down-regulated proteins related to proteolysis activity, the up-regulated proteins were mainly involved in lipid metabolism. Conclusively, BPA exposure impaired male fertility by negatively affecting germ cell proliferation and sperm quality. MLT treatment could alleviate the side effects of BPA by regulating antioxidant molecules, inhibiting germ cell apoptosis, and maintaining male fertility. This study will provide more information for further exploration into the molecular mechanisms of BPA and MLT in male reproduction.
•Bisphenol A treatment impaired germ cell proliferation and sperm quality in mice.•Bisphenol A reduced the expressions of antioxidant molecules and up-regulated apoptosis in testis.•Bisphenol A treatment led to up-regulation of lipid metabolism and down-regulation of proteolysis activity in sperm.•Melatonin could alleviate the side effects induced by Bisphenol A.
Ultrafine-grained (UFG) pure magnesium and AZ31 alloy were prepared by sliding friction treatment (SFT). Nanoindentation tests of UFG Mg and AZ31 alloy were performed under a wide range of loading ...strain rates from 0.004/s to 0.4/s with a holding time of 500s at room temperature to study the grain size and alloy element influence on the creep behavior and the corresponding deformation mechanisms. It is shown that the refined grain size could promote creep behavior, while the alloy elements would enhance the creep resistance. Creep stress exponent deduced in the ending of the holding regime were used to illustrate the creep diversity in these materials. The UFG samples exhibit a reduced creep stress exponent because of significantly increased grain boundary activities. Besides that, the solute atoms of Al and Zn endow the material with an improved creep resistance by limiting interactions between dislocations and boundaries.
Ultrasound-driven bioelectronics could offer a wireless scheme with sustainable power supply; however, current ultrasound implantable systems present critical challenges in biocompatibility and ...harvesting performance related to lead/lead-free piezoelectric materials and devices. Here, we report a lead-free dual-frequency ultrasound implants for wireless, biphasic deep brain stimulation, which integrates two developed lead-free sandwich porous 1-3-type piezoelectric composite elements with enhanced harvesting performance in a flexible printed circuit board. The implant is ultrasonically powered through a portable external dual-frequency transducer and generates programmable biphasic stimulus pulses in clinically relevant frequencies. Furthermore, we demonstrate ultrasound-driven implants for long-term biosafety therapy in deep brain stimulation through an epileptic rodent model. With biocompatibility and improved electrical performance, the lead-free materials and devices presented here could provide a promising platform for developing implantable ultrasonic electronics in the future.
•We performed a TMT-labeled proteomic study on brain and testis of fmr1-deficient mouse.•Expression of a number of proteins in hippocampus and cerebral cortex were changed in the absence of ...fmr1.•Ribosome proteins were largely disturbed in the absence of fmr1.
Fragile X syndrome (FXS), the leading cause of inherited forms of mental retardation and autism, is caused by the transcriptional silencing of fmr1 encoding the fragile X mental retardation protein (FMRP). FMRP is an RNA-binding protein that is a widely expressed, but primarily in the brain and testis, and associated approximately 4% of transcripts. Macro-orchidism is a common symptom associated with FXS both in humans and mice. Thus, we analyze the pooled samples of cerebral cortex, hippocampus and testis from both the fmr1-KO and wild-type mice by a LC–MS/MS proteomic study. Among the identified proteins, most of those showing significant changes in expression were up- or downregulated in the absence of FMRP. Proteins (FMRP, RPS8, RPL23a and ATPIF1, RPL6, GAP43, MTCH2 and MPZ in brain, and FMRP, CAH3, AKR1B7 and C9 in testis) identified by MS/MS were also verified by Western blotting. The Gene Ontology and WikiPathways analysis revealed that the differentially expressed proteins were clustered in the polyribosome and RNA-binding protein categories in both cerebral cortex and hippocampus, but not in testis. Although this study was limited by the little number of samples, our results provide detailed insights into the ribosomal protein profiles of cerebral cortex, hippocampus and testis in the absence of FMRP. Our studies also provide a better understanding of protein profile changes and the underlying dysregulated pathways arising from fmr1 silencing in FXS.
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