Optimized Adsorption-Catalytic Conversion for Lithium Polysulfides by Constructing Bimetallic Compounds for Lithium-Sulfur Batteries.

Although lithium-sulfur batteries possess the advantage of high theoretical specific capacity, the inevitable shuttle effect of lithium polysulfides is still a difficult problem restricting its application. The design of highly active catalysts to promote the redox reaction during charge-discharge and thus reduce the existence time of lithium polysulfides in the electrolyte is the mainstream solution at present. In particular, bimetallic compounds can provide more active sites and exhibit better catalytic properties than single-component metal compounds by regulating the electronic structure of the catalysts. In this work, bimetallic compounds-nitrogen-doped carbon nanotubes (NiCo)Se2-NCNT and (CuCo)Se2-NCNT are designed by introducing Ni and Cu into CoSe2, respectively. The (CuCo)Se2-NCNT delivers an optimized adsorption-catalytic conversion for lithium polysulfide, benefitting from adjusted electron structure with downshifted d-band center and increased electron fill number of Co in (CuCo)Se2 compared with that of (NiCo)Se2. This endows (CuCo)Se2 moderate adsorption strength for lithium polysulfides and better catalytic properties for their conversion. As a result, the lithium-sulfur batteries with (CuCo)Se2-NCNT achieve a high specific capacity of 1051.06 mAh g-1 at 1C and an enhanced rate property with a specific capacity of 838.27 mAh g-1 at 4C. The work provides meaningful insights into the design of bimetallic compounds as catalysts for lithium-sulfur batteries.

Dirammox-dominated microbial community for biological nitrogen removal from wastewater.

Direct ammonia oxidation (Dirammox) might be of great significance to advance the innovation of biological nitrogen removal process in wastewater treatment systems. However, it remains unknown whether Dirammox bacteria can be selectively enriched in activated sludge. In this study, a lab-scale bioreactor was established and operated for 2 months to treat synthetic wastewater with hydroxylamine as a selection pressure. Three Dirammox strains (Alcaligenes aquatilis SDU_AA1, Alcaligenes aquatilis SDU_AA2, and Alcaligenes sp. SDU_A2) were isolated from the activated sludge, and their capability to perform Dirammox process was confirmed. Although these three Dirammox bacteria were undetectable in the seed sludge (0%), their relative abundances rapidly increased after a month of operation, reaching 12.65%, 0.69%, and 0.69% for SDU_A2, SDU_AA1, and SDU_AA2, respectively. Among them, the most dominant Dirammox (SDU_A2) exhibited higher nitrogen removal rate (32.35%) than the other two strains (13.57% of SDU_AA1 and 14.52% of SDU_AA2). Comparative genomic analysis demonstrated that the most dominant Dirammox bacterium (SDU_A2) possesses fewer complete metabolic modules compared to the other two less abundant Alcaligenes strains. Our findings expanded the understanding of the application of Dirammox bacteria as key functional microorganisms in a novel biological nitrogen and carbon removal process if they could be well stabilized. KEY POINTS: • Dirammox-dominated microbial community was enriched in activated sludge bioreactor. • The addition of hydroxylamine played a role in Dirammox enrichment. • Three Dirammox bacterial strains, including one novel species, were isolated.

The validity and reliability of the Chinese version of the biological rhythms interview of assessment in neuropsychiatry in the community: a large Chinese college student population.

Objective: To test the psychometric properties of the Chinese version of the biological rhythms interview of assessment in neuropsychiatry (C-BRIAN) in a group of young adults with and without depressive symptoms. Methods: Three hundred and seventy-eight university students were recruited as participants. Based on the scores from Center for Epidemiological Survey Depression Scale (CES-D), students were divided into the depressed group and healthy group. Explorative factor analysis was applied to assess the construct validity of the C-BRIAN. The Pittsburgh Sleep Quality Index (PSQI) and CES-D were compared with the C-BRIAN to test the convergent validity. The internal consistency of the C-BRIAN was also examined. Results: Three factors were extracted (activities, eating patterns, and sleep factors) explaining 63.9% of the total variance. The internal consistencies were very good with a coefficient of 0.94 (overall) and 0.89-0.91 for three factors. The domains of activities, eating patterns, and sleep were moderately correlated with PSQI (r=0.579) and CES-D (r=0.559) (ps<0.01). Conclusion: Our findings suggest that C-BRIAN has good validity and reliability which can be used to assess the biological rhythm in the young adult population with depressive symptoms. C-BRIAN would be a reliable tool to detect depressive symptoms for timely prevention and intervention in the community.

Short- and medium-chain chlorinated paraffins in breast milk in Shanghai, China: Occurrence, characteristics, and risk assessment.

As novel contaminants, short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) have been of great concern in the past several years. Shanghai was one of the provinces with the largest chlorinated paraffins (CPs) emission in China; nevertheless, there is currently little information on the human exposure to SCCPs and MCCPs, particularly MCCPs. In this study, 25 breast milk samples were collected in Shanghai from 2016 to 2017. The concentrations of SCCPs and MCCPs were determined using two-dimensional gas chromatography coupled with orbitrap high-resolution mass spectrometry (GC × GC-orbitrap-HRMS) to investigate their characteristics and assess the associated health risks for breast-fed infants. Compared with the previous studies in other areas, the current study presented the higher CPs concentrations, with median concentrations of SCCPs and MCCPs up to 771 and 125 ng/g lipid weight (lw), respectively. The exposure profiles of the CPs were characterized by C10 and Cl6-7 as the predominant congeners of SCCPs, while C14 and Cl7-9 were identified as the dominant groups of MCCPs. CP-42 and CP-52 were identified as potential sources of CPs found in breast milk samples collected in Shanghai. The concentrations of MCCPs exhibited a positive correlation (p value < 0.05) with the dietary consumption of meat and poultry. No significant positive correlations were observed for SCCPs and MCCPs with polychlorinated dibenzodioxins/furans (PCDD/Fs) congeners. A preliminary exposure assessment showed that SCCPs in breast milk potentially posed high risks to the breast-fed infants in Shanghai.

Electrochemical route outperforms chemical struvite precipitation in mitigating heavy metal contamination.

Electrochemically mediated struvite precipitation (EMSP) offers a robust, chemical-free process towards phosphate and ammonium reclamation from nutrients-rich wastewater, i.e., swine wastewater. However, given the coexistence of heavy metal, struvite recovered from wastewater may suffer from heavy metal contamination. Here, we systematically investigated the fate of Cu2+, as a representative heavy metal, in the EMSP process and compared it with the chemical struvite precipitation (CSP) system. The results showed that Cu2+ was 100% transferred from solution to solid phase as a mixture of copper and struvite under pHi 9.5 with 2-20 mg/L Cu2+ in the CSP system, and varying pH would affect struvite production. In the EMSP system, the formation of struvite was not affected by bulk pH, and struvite was much less polluted by co-removed Cu2+ (24.4%) at pHi 7.5, which means we recovered a cleaner and safer product. Specifically, struvite mainly accumulates on the front side of the cathode. In contrast, the fascinating thing is that Cu2+ is ultimately deposited primarily to the back side of the cathode in the form of copper (hydro)oxides due to the distinct thickness of the local high pH layer on the two sides of the cathode. In turn, struvite and Cu (hydro)oxides can be harvested separately from the front and back sides of the cathode, respectively, facilitating the subsequent recycling of heavy metals and struvite. The contrasting fate of Cu2+ in the two systems highlights the merits of EMSP over conventional CSP in mitigating heavy metal pollution on recovered products, promoting the development of EMSP technology towards a cleaner recovery of struvite from waste streams.

Effects of Lycium barbarum polysaccharide on cytokines in adolescents with subthreshold depression: a randomized controlled study.

JOURNAL/nrgr/04.03/01300535-202409000-00036/figure1/v/2024-01-16T170235Z/r/image-tiff Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses. Moreover, anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms. Lycium barbarum polysaccharide (LBP), derived from Goji berries, exhibits notable antioxidative and anti-inflammatory properties. In our recent double-blinded randomized placebo-controlled trial, we found that LBP significantly reduced depressive symptoms in adolescents with subthreshold depression. It is presumed that the antidepressant effect of LBP may be associated with its influence on inflammatory cytokines. In the double-blinded randomized controlled trial, we enrolled 29 adolescents with subthreshold depression and randomly divided them into an LBP group and a placebo group. In the LBP group, adolescents were given 300 mg/d LBP. A 6-week follow up was completed by 24 adolescents, comprising 14 adolescents from the LBP group (15.36 ± 2.06 years, 3 men and 11 women) and 10 adolescents from the placebo group (14.9 ± 1.6 years, 2 men and 8 women). Our results showed that after 6 weeks of treatment, the interleukin-17A level in the LBP group was lower than that in the placebo group. Network analysis showed that LBP reduced the correlations and connectivity between inflammatory factors, which were associated with the improvement in depressive symptoms. These findings suggest that 6-week administration of LBP suppresses the immune response by reducing interleukin-17A level, thereby exerting an antidepressant effect.

Basket anode filled with CaCO3 particles: A membrane-free electrochemical system for boosting phosphate recovery and product purity.

Phosphorus (P) is often regarded as the primary stimulant for eutrophication, while its importance as a crucial life element is also well acknowledged. Given its future scarcity, P recycling from waste streams is suggested and practiced. Electrochemically mediated precipitation (EMP) is a robust and chemical-free process for P removal and recovery, yet it requires further developments. The first generation of the CaCO3-packed electrochemical precipitation column successfully solved the problem of H+-OH- recombination, achieving enhanced P removal efficiency with less energy consumption but suffering from low Ca-phosphate purity in recovered products. Herein, a new concept of a basket-anode electrochemical system is proposed and validated to prevent direct H+-OH- recombination and enhance product purity. The CaCO3 pellets packed basket anode alleviates the OH- depletion by CaCO3-H+ interaction and provides extra Ca2+ for enhanced P removal. The novel structure of the basket anode, by its derived acidic anode region and alkaline cathode region, completely avoids the precipitation of Ca-phosphate on the packed CaCO3 and greatly facilitates the collection of high-quality Ca-phosphate product. Our results suggest that almost 100% of the removed P was in high-purity, highly crystalline Ca-phosphate on the cathode. The recovered products contained significantly more P (13.5 wt%) than in the previous study (0.1 wt%) at similar energy consumptions (29.8 kWh/kg P). The applied current density, pellets size, and influent P concentration were critical for P removal performance, product purity, and power consumption. We further demonstrated the long-term stability of this novel system and its technical and economic feasibility in treating real stored urine. Our study provides new cell architectural designs to enhance the performance of EMP systems and may inspire innovations and developments in other electrochemical water treatment processes.

Exercise effect on the gut microbiota in young adolescents with subthreshold depression: A randomized psychoeducation-controlled Trial.

This 3-month randomized psychoeducation-controlled trial (RCT) of exercise was undertaken in young adolescents with subthreshold depression to examine the impact on gut microbiota. Participants (aged 12-14 years) were randomly assigned to an exercise or a psychoeducation-controlled group. The exercise intervention arm took moderate-intensity exercise, comprised of 30 min of running per day, 4 days a week for 3 months. Psychoeducation intervention consisted of 6 sessions of group activity including gaming, reading, and singing. The gut microbiota was assessed by metagenomic sequencing. After 3-month moderate-intensity exercise, the intervention group increased the relative abundance of Coprococcus, Blautia, Dorea, Tyzzerella at the genus level, as well as Tyzzerella nexilis, Ruminococcus obeum at species level when compared to the psychoeducation-controlled group. Moreover, EggNOG analyses showed that the defense and signal transduction mechanism were highly enriched after the active intervention, and changes were correlated with improvements in depressive symptoms measured by Chinese Patient Depression Questionnaire 9. The KEGG pathway of neurodegenerative diseases was depleted in the microbiome in young adolescents with subthreshold depression after exercise intervention. This 3-month RCT suggests that at both the genus and species levels, aerobic group exercise intervention improved in depressive symptoms and revealed changes in gut microbiota suggesting beneficial effects.

Soil microbiomes divergently respond to heavy metals and polycyclic aromatic hydrocarbons in contaminated industrial sites.

Contaminated sites from electronic waste (e-waste) dismantling and coking plants feature high concentrations of heavy metals (HMs) and/or polycyclic aromatic hydrocarbons (PAHs) in soil. Mixed contamination (HMs + PAHs) hinders land reclamation and affects the microbial diversity and function of soil microbiomes. In this study, we analyzed HM and PAH contamination from an e-waste dismantling plant and a coking plant and evaluated the influences of HM and PAH contamination on soil microbiomes. It was noticed that HMs and PAHs were found in all sites, although the major contaminants of the e-waste dismantling plant site were HMs (such as Cu at 5,947.58 ± 433.44 mg kg-1, Zn at 4,961.38 ± 436.51 mg kg-1, and Mn at 2,379.07 ± 227.46 mg kg-1), and the major contaminants of the coking plant site were PAHs (such as fluorene at 11,740.06 ± 620.1 mg kg-1, acenaphthylene at 211.69 ± 7.04 mg kg-1, and pyrene at 183.14 ± 18.89 mg kg-1). The microbiomes (diversity and abundance) of all sites were determined via high-throughput sequencing of 16S rRNA genes, and redundancy analysis was conducted to investigate the relations between soil microbiomes and contaminants. The results showed that the microbiomes of the contaminated sites divergently responded to HMs and PAHs. The abundances of the bacterial genera Sulfuritalea, Pseudomonas, and Sphingobium were positively related to PAHs, while the abundances of the bacterial genera Bryobacter, Nitrospira, and Steroidobacter were positively related to HMs. This study promotes an understanding of how soil microbiomes respond to single and mixed contamination with HMs and PAHs.

Increased plasma level of kynurenic acid in drug-free patients with first-episode schizophrenia compared to patients with chronic schizophrenia and healthy controls: preliminary data.

BACKGROUND: Kynurenic acid (KYNA) is a metabolite of tryptophan (TRP). KYNA levels have been reported with controversial findings in patients with schizophrenia. AIM: This study aimed to investigate the probable effects of medication and illness chronicity on peripheral KYNA levels in schizophrenia. METHODS: We assessed peripheral (plasma) TRP metabolite levels in 38 drug-free patients with first-episode schizophrenia (FES), 65 patients with chronic schizophrenia (CHS), and 70 healthy controls by using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The symptom severity of patients was evaluated by using the Positive and Negative Syndrome Scale (PANSS). Finally, we analyzed the association of TRP metabolites with symptom severity. RESULTS: We found significantly higher KYNA levels in FES patients than in both healthy controls (p < 0.01) and CHS patients (p < 0.05). No significant association was observed between plasma TRP metabolite levels and PANSS scores in either FES or CHS patients. CONCLUSIONS: In conclusion, elevated plasma KYNA levels may be a promising biomarker in FES patients. Medication and illness chronicity may affect peripheral KYNA levels with a currently unknown mechanism.

Repetitive Transcranial Magnetic Stimulation Target Location Methods for Depression.

Major depressive disorder (MDD) is a substantial global public health problem in need of novel and effective treatment strategies. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive and promising treatment for depression that has been approved by the U.S. Food and Drug Administration (FDA). However, the methodological weaknesses of existing work impairs the universal clinical use of rTMS. The variation of stimulated targets across the dorsolateral prefrontal cortex may account for most of the heterogeneity in the efficacy of rTMS. Many rTMS target location methods for MDD have been developed in recent decades. This review was conducted to assess this emerging field and to improve treatment outcomes in clinical practice.

Individualized rTMS Treatment for Depression using an fMRI-Based Targeting Method.

To achieve greater clinical efficacy, a revolution in treatment for major depressive disorder (MDD) is highly anticipated. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive and safe neuromodulation technique that immediately changes brain activity. Despite its wide application in the treatment for MDD, the treatment response remains different among individuals, which may be attributable to the inaccurate positioning of the stimulation target. Our study aims to examine whether the functional magnetic resonance imaging (fMRI)-assisted positioning improves the efficacy of rTMS in treating depression. We intend to identify and stimulate the subregion of dorsolateral prefrontal cortex (DLPFC) in MDD with strongest anti-correlation with the subgenual anterior cingulate cortex (sgACC), and to conduct a comparative investigation of this novel method and the traditional 5-cm rule. To achieve more precise stimulation, both methods were applied under the guidance of neuronavigation system. We expected that the TMS treatment with individualized positioning based on resting state functional connectivity may show better clinical efficacy than the 5-cm method.

Effects of aerobic exercise on gut microbiota in adolescents with subthreshold mood syndromes and healthy adolescents: A 12-week, randomized controlled trial.

BACKGROUND: Animal and human studies have revealed reciprocal association between exercise and gut-brain axis. However, the clinical evidence from randomized controlled trials (RCT) are still limited to directly assess the effects of aerobic exercise on gut microbiota. To fill this gap, we conducted this 12-week RCT in both groups of adolescents with and without sub-threshold mood symptoms. METHODS: A total of 224 adolescents were randomized to the aerobic exercise intervention or psychoeducation-controlled arm. 49 adolescents with subthreshold symptoms and 142 clinically-well adolescents provided the sample for microbiota assessed by metagenomic sequencing. Aerobic exercise of running at the moderate-intensity for 30 min per day, 5 days a week, were conducted for 12 weeks. RESULTS: Adolescents with subthreshold symptoms had significantly lower beta diversity than clinically-well adolescents in both the exercise intervention and psychoeducation-controlled arms (p<0.05). After intervention, no difference in gut microbiota diversity, phylum, genus, species level abundancies or gut microbial functions were found in both of the symptomatic or non-symptomatic groups. Metagenome-wide association study analysis showed no significant difference in metagenomic linkage groups. LIMITATIONS: The sample size is relatively small. The exercise intensity we employed may be insufficient to result in observable effects on intestinal microbiota. CONCLUSION: We conclude that a 12-week moderate-intensity aerobic exercise intervention showed no significant beneficial effect on the gut microbiota in clinically-well adolescents as well as in adolescents with subthreshold symptoms. The beta diversity of gut microbiota in adolescents with subthreshold mood syndromes may be impaired when compared with clinically-well adolescents.

Aerobic exercise impacts the anterior cingulate cortex in adolescents with subthreshold mood syndromes: a randomized controlled trial study.

Aerobic exercise is effective in alleviating mood symptoms while the mechanism is poorly understood. There are limited clinical trials that investigated the effect of exercise on the anterior cingulate cortex (ACC), a key brain region involved in mood regulations, in adolescents with subthreshold mood syndromes. This randomized controlled trial (RCT) of aerobic exercise was undertaken in a middle school in Guangzhou, China. Participants were adolescents aged 12-14 with subthreshold mood syndromes including depressive and manic symptoms and were randomly assigned to an aerobic exercise intervention or a psychoeducation control group. Participants in the exercise group received moderate-intensity exercise intervention, consisting of 30 mins running, 4 days per week for 3 months. The primary outcome in this study was structural changes in the ACC from baseline to post intervention. The trial was registered with ClinicalTrial.gov (NCT03300778). Of 56 participants who met the criteria for subthreshold mood syndromes, 39 (41.03% males) had complete MRI data, with 20 and 19 subjects in the exercise and control group, respectively. At baseline, demographic information (e.g., age and sex), clinical symptoms, and the gray matter volume and cortical thickness of ACC were matched between the two groups. After 12 weeks of treatment, participants in the exercise group displayed increased gray matter volume of the left rostral ACC (F1,30 = 5.73, p = 0.02) and increased cortical thickness of the right rostral ACC (F1,30 = 7.83, p = 0.01) when compared with the control group. No significant differences were found for caudal ACC cortical thickness and gray matter volume. Our data demonstrate that 12-week, moderate-intensity aerobic exercise can induce structural changes in the rostral ACC in adolescents with subthreshold mood syndromes.

Heterogeneous oxidation of isoprene SOA and toluene SOA tracers by ozone.

Secondary Organic aerosols (SOA) are important components of PM 2.5. In order to control the heavy haze pollution, it is essential to find out the contributions of main SOA precursors. Nowadays, the tracer-based method has been widely used in analyzing the contributions of the precursors to SOA. However, it is not well known that whether the SOA tracers can be oxidized or how the instability of the SOA tracers would influence the accuracy of the tracer-based method for source apportionment. In this paper, the heterogeneous oxidation experiments of SOA tracers produced from isoprene and toluene as well as their mixtures under different conditions were conducted in a 2 m3 indoor chamber. The relative rate constants approach was used to determine the effective rate constants of the ozone reactions of the tracers. Concentrations of 2-Methyl Erythritol, a tracer of isoprene SOA, and 2, 3-Dihydroxy-4-oxopentanoic Acid, a tracer of toluene SOA, were analyzed using GC-MS. The effects of different seed aerosols and initial VOC0/NO on the heterogeneous oxidation of the tracers were investigated. The effects of co-existing components in the SOA produced from the mixture of isoprene and toluene on the heterogeneous oxidation of the tracers by ozone were also studied.

Inflammation, brain structure and cognition interrelations among individuals with differential risks for bipolar disorder.

Neuro-inflammation might impact on clinical manifestations and cognition function via changing the volumes of key brain structures such as the anterior cingulate cortex (ACC) in bipolar disorder (BD). In this study, we investigated the interrelations among interleukin (IL)-6 cytokine level, grey matter (GM) volume of the anterior cingulated cortex (ACC), and attention function among offspring of parents diagnosed with BD. The offspring were categorized as being either asymptomatic or symptomatic based on whether they manifested pre-defined sub-threshold mood symptoms. We found that the symptomatic offspring showed significantly higher serum levels of IL-6 than the asymptomatic offspring (F(1, 59) = 67.65, p < 0.001). On the brain level, we obtained significant interactive effect of group and IL6 level on the ACC GM (PFWE = 0.017). Specifically, the GM volume of the rostral ACC was negatively associated with the levels of IL-6 in the asymptomatic offspring (PFWE = 0.021), but not the symptomatic offspring (PFWE > 0.05). Mediation analyses revealed that the GM volume of the rostral ACC significantly mediated the negative association between the IL-6 levels and attention performance in the asymptomatic offspring (bootstrapping Confidence Interval (CI) = -6.0432 to -0.0731) but not the symptomatic offspring (bootstrapping CI = -0.3197 to 1.3423). Our data suggest that the asymptomatic and symptomatic bipolar offspring may exhibit different neurocognitive-inflammatory profiles, which could be further validated as viable biosignatures for BD risk and resilience.

Characterization of short- and medium-chain chlorinated paraffins in cereals and legumes from 19 Chinese provinces.

Short-chain chlorinated paraffins (SCCPs) were added to the Stockholm Convention Annex A in May 2017. China is the largest producer of chlorinated paraffins (CPs). CPs in the environment can be transferred to foodstuffs directly and through bioaccumulation and then ingested by humans. Cereals and legumes are important components of Chinese diets, so the risks posed by CPs in cereals and legumes should be of concern. 1710 cereal samples and 1710 legume samples from 19 Chinese provinces were pooled by type and province (giving 19 pooled cereal and 19 pooled legume samples). The SCCP and medium-chain chlorinated paraffin (MCCP) concentrations in the samples were determined by comprehensive two-dimensional gas chromatography tandem time-of-flight mass spectrometry (GC × GC-TOFMS). The mean SCCP concentrations in the cereal and legume samples were 343 and 328 ng g-1 wet weight (ww), respectively, and the mean MCCP concentrations were 213 and 184 ng g-1 ww, respectively. The dominant SCCP congener groups were C10Cl6-7 in cereals and C10Cl5-6 in legumes. The MCCP congener groups C14Cl6-7 were dominant in both cereals and legumes. The CP concentrations were higher in samples from eastern China than in samples from other regions. Risk assessments indicated that SCCPs and MCCPs in cereals and legumes do not pose strong risks to Chinese residents.

Spatial distributions and transport implications of short- and medium-chain chlorinated paraffins in soils and sediments from an e-waste dismantling area in China.

To investigate the spatial distributions, potential transport and ecological risks of chlorinated paraffins (CPs) in and around e-waste dismantling area, we collected soil samples within 5 km of the e-waste dismantling centers and sediment samples in the surrounding area from the lower reaches of Jiaojiang River. Short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) were analyzed by two-dimensional gas chromatography coupled with electron-capture negative-ionization mass spectrometry (GC × GC-ECNI-MS). The SCCP and MCCP concentration ranges in soils were 68.5 to 2.20 × 105 ng/g dry weight (dw) and 507 to 4.40 × 106 ng/g dw, respectively. The ranges for the levels of SCCPs and MCCPs in sediments were 32.5-1.29 × 104 ng/g dw and 271-2.72 × 104 ng/g dw, respectively. No significant correlation was observed between total organic carbon (TOC) and CP concentrations (P > 0.05). The spatial distributions showed that the CP levels were closely related to e-waste pollution. Correspondence analysis revealed that shorter-chain and less chlorinated congeners were enriched in sediments from sites distant from e-waste pollution source, while longer-chain and higher chlorinated congeners were concentrated in soils and sediments collected near the pollution source, which indicated that complex environmental processes, such as transportation via atmosphere and/or water, and deposition, resulted in different CP profiles in different sampling locations and environment matrixes (e.g., soil and sediments). Principal component analysis (PCA) indicated that e-waste pollution could be the same source of SCCPs and MCCPs. The preliminary risk assessment indicated that CPs in soils within 1 km of e-waste dismantling centers at current levels posed a considerable risk to soil-dwelling organisms, and the sediment MCCPs in Jiaojiang estuary at present levels also posed a risk to sediment-dwelling organisms.

Knockdown of CLC-3 in the hippocampal CA1 impairs contextual fear memory.

Previous studies support a critical role of hippocampus in contextual fear memory. Structural and functional alterations of hippocampus occur frequently in posttraumatic stress disorders (PTSD). Recent reports reveal that knockout of CLC-3, a member of the CLC family of anion channels and transporters, leads to neuronal degeneration and loss of hippocampus. However, the role of CLC-3 in contextual fear memory remains unknown. Using adenovirus and adeno-associated virus gene transfer to knockdown CLC-3 in hippocampal CA1, we investigate the role of CLC-3 in contextual fear memory. CLC-3 expression is increased in hippocampal CA1 after formation of long-term contextual fear memory. Knockdown of CLC-3 by adenovirus infusion in hippocampal CA1 significantly attenuates the contextual fear memory, reduces spine density, induces defects of excitatory synaptic ultrastructure showed by the decreased PSD length, PSD thickness and active zone length, and impairs L-LTP induction and maintenance. Knockdown of CLC-3 also induces the synaptic NMDAR subunit composition to an increased GluN2A/GluN2B ratio pattern and reduces the activity of CaMKII-α. Furthermore, selectively knockdown of CLC-3 in excitatory neurons by adeno-associated virus driven from CaMKII-α promoter is sufficient to impair long-term contextual fear memory. These findings highlight that CLC-3 in hippocampal CA1 is necessary for contextual fear memory.

Maternal Deprivation Enhances Contextual Fear Memory via Epigenetically Programming Second-Hit Stress-Induced Reelin Expression in Adult Rats.

Background: Early-life stress increases the risk for posttraumatic stress disorder. However, the epigenetic mechanism of early-life stress-induced susceptibility to posttraumatic stress disorder in adulthood remains unclear. Methods: Rat pups were exposed to maternal deprivation during postnatal days 1 to 14 for 3 hours daily and treated with the DNA methyltransferase inhibitor zebularine, L-methionine, or vehicle 7 days before contextual fear conditioning, which was used as a second stress and to mimic the reexperiencing symptom of posttraumatic stress disorder in adulthood. Long-term potentiation, dendritic spine density, DNA methyltransferase mRNA, Reelin gene methylation, and Reelin protein expression in the hippocampal CA1 were measured. Results: Maternal deprivation enhanced contextual fear memory in adulthood. Meanwhile, maternal deprivation decreased DNA methyltransferase mRNA and Reelin gene methylation in the hippocampal CA1 on postnatal days 22 and 90. Reelin protein expression was increased in the hippocampal CA1 following contextual fear conditioning in adulthood. Furthermore, compared with rats that experienced maternal deprivation alone, rats also exposed to contextual fear conditioning showed an enhanced induction of hippocampal long-term potentiation and increased dendritic spine density in the hippocampal CA1 following contextual fear conditioning in adulthood. Zebularine pretreatment led to an enhancement of contextual fear memory, hypomethylation of the Reelin gene, and increased Reelin protein expression in adult rats, while L-methionine had the opposite effects. Conclusions: Maternal deprivation can epigenetically program second-hit stress-induced Reelin expression and enhance the susceptibility to contextual fear memory in adulthood. These findings provide a new framework for understanding the cumulative stress hypothesis.