Metabolic and immune costs balance during natural acclimation of corals in fluctuating environments.

Epigenetic modifications based on DNA methylation can rapidly improve the potential of corals to adapt to environmental pressures by increasing their phenotypic plasticity, a factor important for scleractinian corals to adapt to future global warming. However, the extent to which corals develop similar adaptive mechanisms and their specific adaptation processes remain unclear. Here, to reveal the regulatory mechanism by which DNA methylation improves thermal tolerance in Pocillopora damicornis under fluctuating environments, we analyzed genome-wide DNA methylation signatures in P. damicornis and compared the differences in the methylation and transcriptional responses of P. damicornis from fluctuating and stable environments using whole-genome bisulfite sequencing and nanopore-based RNA sequencingtranscriptome sequencing. We discovered low methylation levels in P. damicornis (average methylation 4.14%), with CpG accounting for 74.88%, CHH for 13.27%, and CHG for 11.85% of this methylation. However, methylation levels did not change between coral samples from the fluctuating and stable environments. The varied methylation levels in different regions of the gene revealed that the overall methylation level of the gene body was relatively high and showed a bimodal methylation pattern. Methylation occurs primarily in exons rather than introns within the gene body In P. damicornis, there was only a weak correlation between methylation and transcriptional changes at the individual gene level, and the methylation and gene expression levels generally exhibited a bell-shaped relationship, which we speculate may be due to the specificity of cnidarian species. Correlation analysis between methylation levels and the transcriptome revealed that the highest proportion of the top 20 enriched KEGG pathways was related to immunity. Additionally, P. damicornis collected from a high-temperature pool had a lower metabolic rate than those collected from a low-temperature pool. We hypothesize that the dynamic balance of energy-expenditure costs between immunity and metabolism is an important strategy for increasing P. damicornis tolerance. The fluctuating environment of high-temperature pools may increase the heat tolerance in corals by increasing their immunity and thus lowering their metabolism.

Occurrence, distribution, and ecological risk assessment of artificial sweeteners in surface and ground waters of the middle and lower reaches of the Yellow River (Henan section, China).

As a new class of water contaminants, artificial sweeteners (ASs) have attracted much attention due to their environmental persistence and potential adverse effects to human and the environment. This study systematically investigated the occurrence and distribution of four commonly used ASs in the effluent of wastewater treatment plants (WWTPs), surface water and groundwater in the middle and lower reaches of the Yellow River (Henan section). Sucralose (SUC) was dominant in WWTP effluents and had the highest mass loading. Acesulfame (ACE), cyclamate (CYC), saccharin (SAC), and SUC were consistently detected in surface water at concentrations ranging from 1.364 ng/L (CYC) to 7786 ng/L (ACE). Spatial analysis showed that the pollution level of ASs in the trunk stream was lower than that in most tributaries. The total concentrations of ASs detected in surface water ranged between 308.7 and 10,498 ng/L, while in groundwater, the total concentration of ASs detected was between ND-4863 ng/L. ACE and SUC are the main pollutants in surface water and groundwater within this survey area. The risk assessment showed that the risks of the four target ASs to aquatic organisms were negligible (risk quotient (RQ) values < 0.1), and the maximum risk quotient of the mixtures (MRQ) values of all rivers were all much less than 0.1.

Occurrence, distribution, and ecological risk assessment of pharmaceuticals and personal care products in the surface water of the middle and lower reaches of the Yellow River (Henan section).

Pharmaceuticals and personal care products (PPCPs) are commonly seen emerging organic contaminants in aquatic environments. The transects for the occurrence and distribution of 24 PPCPs along the middle and lower reaches of the Yellow River (Henan section) were investigated in this study. All 24 targeted compounds were detected in surface water, with concentrations in the range from not detected (ND) to 527.4 ng/L. Among these PPCPs, caffeine is found to have the highest concentration and its detection frequency is 100%. The total PPCP concentration ranged from 136 ng/L to 916 ng/L (median, 319.5 ng/L). Spatial analysis showed that the pollution level of PPCPs in the trunk stream was lower than that in most tributaries in the middle and lower reaches of the Yellow River (Henan section). The ecotoxicological risk assessment indicated that norfloxacin, azithromycin, estrone, and triclosan posed high risks to aquatic organisms (RQ > 1), roxithromycin and oxytetracycline imposed moderate risks (0.1 ≤ RQ < 1), and the tributary Jindi River had the highest mixed risk (MRQ = 222).

Preliminary Assessment of Chinese Strategy in Controlling Reemergent Local Outbreak of COVID-19.

Reemergent local outbreaks of coronavirus disease 2019 (COVID-19) have occurred in China, yet few Chinese response strategies and its evaluation have been reported. This study presents a preliminary assessment of Chinese strategy in controlling reemergent local outbreaks of COVID-19. Time course of accumulative and daily new cases and time-varying reproductive numbers (Rt) of outbreak areas were presented. The asymptomatic rate, days required to control the outbreaks, seeding time (ST), and doubling time (DT) of areas with over 96 reemergent cases were calculated. National and local year-on-year growth rates of gross domestic product (GDP) were presented. Accumulative numbers of 30, 8, 11, 430, 15, 139, 1,067, 382, 42, and 94 confirmed reemergent COVID-19 cases were diagnosed in Hulun Buir, Shanghai, Tianjin, Kashgar, Qingdao, Dalian, Urumchi, Beijing, Jilin, and Harbin, respectively. Among them, maximum rate of asymptomatic infections was 81.9%. Time required to control the local outbreaks in the areas given above varied from 29 to 51 days. After activation of outbreak responses, the late-stage DTs of Kashgar, Urumchi, Beijing, and Dalian were apparently lengthened compared to the early-stage DTs. Although the year-on-year GDP growth rate of Urumchi was slightly affected, the GDP growth rate of Dalian, Beijing, Jilin, and Harbin kept rising during the reemergence. Moreover, the year-on-year GDP growth rate of Mainland China turned positive regardless of the reemergent local outbreaks. In general, the Chinese strategy to maintain the status of no or minimal transmission was effective in balancing the control of COVID-19 reemergent local outbreak and the recovery of economy.

Assessment of biological functions for C3A cells interacting with adverse environments of liver failure plasma.

BACKGROUND: For its better differentiated hepatocyte phenotype, C3A cell line has been utilized in bioartificial liver system. However, up to now, there are only a few of studies working at the metabolic alternations of C3A cells under the culture conditions with liver failure plasma, which mainly focus on carbohydrate metabolism, total protein synthesis and ureagenesis. In this study, we investigated the effects of acute liver failure plasma on the growth and biological functions of C3A cells, especially on CYP450 enzymes. METHODS: C3A cells were treated with fresh DMEM medium containing 10% FBS, fresh DMEM medium containing 10% normal plasma and acute liver failure plasma, respectively. After incubation, the C3A cells were assessed for cell viabilities, lactate dehydrogenase leakage, gene transcription, protein levels, albumin secretion, ammonia metabolism and CYP450 enzyme activities. RESULTS: Cell viabilities decreased 15%, and lactate dehydrogenase leakage had 1.3-fold elevation in acute liver failure plasma group. Gene transcription exhibited up-regulation, down-regulation or stability for different hepatic genes. In contrast, protein expression levels for several CYP450 enzymes kept constant, while the CYP450 enzyme activities decreased or remained stable. Albumin secretion reduced about 48%, and ammonia accumulation increased approximately 41%. CONCLUSIONS: C3A cells cultured with acute liver failure plasma showed mild inhibition of cell viabilities, reduction of albumin secretion, and increase of ammonia accumulation. Furthermore, CYP450 enzymes demonstrated various alterations on gene transcription, protein expression and enzyme activities.