Suppression of interleukin-2 by the putative endogenous cannabinoid 2-arachidonyl-glycerol is mediated through down-regulation of the nuclear factor of activated T cells.

ABSTRACT 2-Arachidonyl-glycerol (2-Ara-Gl) recently was identified as a putative endogenous ligand for cannabinoid receptor types CB1 and CB2 by competitive binding. More recent immune function assays demonstrated that 2-Ara-Gl possessed immunomodulatory activity. Because several plant-derived cannabinoids inhibit interleukin-2 (IL-2) expression, 2-Ara-Gl was investigated for its ability to modulate this cytokine. The direct addition of 2-Ara-Gl to mouse splenocyte cultures suppressed phorbol-12-myristate-13-acetate plus ionomycin-induced IL-2 secretion and steady state mRNA expression in a dose-dependent manner. 2-Ara-Gl also produced a marked inhibition of IL-2 promotor activity as determined by transient transfection of EL4.IL-2 cells with a pIL-2-CAT construct. 2-Ara-Gl at 5, 10, 20, and 50 M suppressed phorbol-12-myristate-13-acetate plus ionomycin-induced IL-2 promotor activity by 18%, 28%, 39%, and 54%, respectively. To further characterize the mechanism for the transcriptional regulation of IL-2 by 2-Ara-Gl, the DNA-binding activity of transcription factors, nuclear factor of activated T cells (NF-AT), nuclear factor for immunoglobulin chain in B cells (NF-B/Rel), activator protein-1(AP-1), octamer, and cAMP-response element binding protein was evaluated by electrophoretic mobility shift assay in mouse splenocytes. In addition, a reporter gene expression system for p(NF-B) 3 -CAT, p(NF-AT) 3 -CAT, and p(AP-1) 3 -CAT was used in transiently transfected EL4.IL-2 cells to determine the effect of 2-Ara-Gl on promoter activity for each of the specific transcription factors. 2-Ara-Gl reduced both the NF-AT-binding and promoter activity in a dose-dependent manner and, to a lesser degree, NF-B/Rel-binding and promoter activity. No significant effect was observed on octamer-and cAMP-response element-binding activity. AP-1 DNA-binding activity was not inhibited by 2-AraGl, but a modest inhibition of promoter activity was observed

Demographic and genetic characterization of harvested Corbicula fluminea populations

The freshwater clam Corbicula fluminea s.l. is an edible freshwater bivalve of economic value in Asia. The species has been particularly well studied in the invaded range. However, there is a lack of knowledge in its native range where it supports an increasing commercial harvest pressure. Among Asiatic countries, China accounts for 70% of known commercial harvest and aquaculture production. We aim to characterize here wild C. fluminea s.l populations exposed to commercial harvest pressure in Poyang Lake Basin. We found higher biomass, density and genetic diversity in lake populations compared to peripheral populations (i.e., lake tributaries). Given that lake habitats support more intense harvest pressure than peripheral habitats, we suggest that demographic and genetic differentiation among subpopulations may be influenced in some degree by different harvest pressure. In this regard, additional demographic and/or genetic changes related to increasing harvest pressure may place population at a higher risk of extirpation. Altogether, these results are especially relevant for maintaining populations at or above viable levels and must be considered in order to ensure the sustainability of the resource

Experimental Study on Acoustic Emission of Confined Compression of Crushed Gangue under Different Loading Rates: Disposal of Gangue Solid Waste

The crushed gangue materials which are filled into the goaf in solid-backfilling coal mining become the main body of bearing the overburden after the tamping process. Its resistance to deformation is the key to control overburden movement and surface subsidence. Particle breakage affects the resistance to deformation of filling materials. In this paper, a confined compression test of crushed gangue under different loading rates was designed, and the acoustic emission (AE) signal was monitored in the process of confined compression. The test results showed that with the increase of loading rate, the anti-deformation ability of crushed gangue showed a dynamic change process of increasing, decreasing, and then increasing again. With the increase of loading rate, the breakage degree of the samples decreased, the proportion of large-sized gangue increased, the growth period of AE counts showed an obvious hysteresis phenomenon, and the AE activity level of the gangue increased gradually. The research results can not only provide a more in-depth and comprehensive understanding of the mechanical properties of crushed gangue filling materials but also provide a reference for the engineering application of solid-filling coal mining

Spatial Distribution and Temporal Trends of Dietary Niacin Intake in Chinese Residents ≥ 5 Years of Age between 1991 and 2018

Limited knowledge exists on trends in niacin consumption and the prevalence of inadequate intakes in China. Understanding trends and the spatial distribution of the prevalence of inadequate niacin intake is crucial to identifying high-risk areas and sub-populations. The dietary intakes of niacin between 1991 and 2018 were analyzed using the China Health and Nutrition Survey (CHNS) data. The estimated average requirement cut point was applied to estimate inadequacy. The geographic information system’s ordinary kriging method was used to estimate the spatial distribution of the prevalence of inadequate niacin intakes. However, between 1991 and 2018, the prevalence of inadequate niacin intake increased from 13.00% to 28.40% in females and from 17.75% to 29.46% in males. Additionally, the geographically significant clusters of high and low prevalence were identified and remained stable over almost three decades. The high prevalence of insufficient niacin intake was more pronounced in Henan and Shandong over 27 years. Further, effective and tailored nutrition interventions are required to address inadequate niacin intake in China

Crystal structure of the human SUV39H1 chromodomain and its recognition of histone H3K9me2/3.

SUV39H1, the first identified histone lysine methyltransferase in human, is involved in chromatin modification and gene regulation. SUV39H1 contains a chromodomain in its N-terminus, which potentially plays a role in methyl-lysine recognition and SUV39H1 targeting. In this study, the structure of the chromodomain of human SUV39H1 was determined by X-ray crystallography. The SUV39H1 chromodomain displays a generally conserved structure fold compared with other solved chromodomains. However, different from other chromodomains, the SUV39H1 chromodomain possesses a much longer helix at its C-terminus. Furthermore, the SUV39H1 chromodomain was shown to recognize histone H3K9me2/3 specifically