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Green rust (GR), as a vital intermediate product during the formation of various iron oxides, exists with organic matters and metals contaminants in natural environments. Understanding the effects of these natural factors on the transformation process of GR into iron oxides and the environmental behaviors of heavy metals and organic matters during process are critical for environmental quality management, but the fundamental identification of the interaction mechanisms between them and GR is still challenging. In this study, the transformation mechanisms of Co-bearing green rust (GR-Co) synthesized by co-precipitation, and the redistribution behaviors of Co(II) in an environment containing oxalic acid (OA) and citric acid (CA) were clarified. The findings indicated that OA promoted the Fe(II) dissolution and the transformation of GR-Co to goethite, while CA decreased the Fe(II) dissolution and the proportion of non-extractable Co. Furthermore, in the presence of CA, the transformation products of GR-Co were ferrihydrite, magnetite, lepidocrocite and goethite instead of only lepidocrocite and goethite. Meanwhile, CA prohibited ferrihydrite from transforming into more highly crystalline iron minerals. The finding of this study improves the understanding of the interaction mechanisms between GR-Co and organic matter, and the environmental geochemical behaviors of Co and organic carbon during the transformation processes in nature. [Display omitted] • OA and CA affected the behaviors of Co during the GR-Co transformation. • Organic carbon sequestration behaviors were studied during the conversion. • OA promoted the transformation of GR-Co from lepidocrocite to goethite. • CA inhibited the transformation of GR-Co into minerals with high crystallinity. [ABSTRACT FROM AUTHOR]

• Exosomal transfer of GC cell-derived miR-92b-5p facilitates TAMs M2 polarization through sustained STAT3 activation. • PLXNC1 upregulates exosomal miR-92b-5p expression derived from GC cells through activating MEK1/MSK1/CREB1 signaling pathway. • STAT3 achieves self-activation by mediating the transfer of GC cell-derived exosomal miR-92b-5p to macrophages. • EGCG derived from HDW targets STAT3 to inhibit M2 polarization induced by PLXNC1 -mediated GC cell-derived exosomes. M2-polarized tumor-associated macrophages (TAMs) predominate in tumor microenvironment (TME) and serve primary functions in tumor progression, including growth, angiogenesis, metastasis, immunosuppression, chemoresistance, and poor prognosis. The reversal of M2 polarization provides a new treatment strategy for cancer. Presently, the molecular mechanisms of M2 polarization have yet to be fully characterized, and there is a lack of effective therapeutic targets and drugs. Cancer cells initiate an immunosuppressive TME by recruiting macrophages and promoting M2 polarization through the secretion of inflammatory factors. Accordingly, blocking cancer cell-induced TAM M2 polarization may present a more effective strategy from the perspective of cancer cells. Hedyotis diffusa Willd (HDW) possesses immunomodulatory and antitumor properties, and is a precious and direct source of small molecule natural products with a dual function of inhibition of tumor growth and tumor cell-mediated M2 polarization. To identify a new target promoting gastric cancer (GC) cell growth and GC cell-mediated M2 polarization from mRNA profiles of GC cells treated with HDW injection (HDI) and to excavate a natural product from HDI that can regulate related mRNA and inhibit the aforementioned effects. RNA sequencing (RNA-seq) was used to analyze HDI-regulated differentially expressed mRNAs (HRmRNAs) in MKN45 cells. Weighted gene co-expression network analysis (WGCNA), univariate and multivariate Cox regression analysis, KM survival curves, and association analysis between HRmRNA and clinical characteristics/tumor infiltrating immune cells (TIICs) individually were utilized to screen out the target HRmRNA associated with prognosis and M2 macrophage infiltration in GC. shRNA lentiviral vectors were used for stably silencing, and transient overexpressing plasmids were constructed for overexpression. CCK8, EdU, colony formation, migration and invasion assays were used to validate the function of drugs and molecules in GC. HDI constituent analysis was performed using UHPLC-QE-MS. A network of HDI constituent-hub transcription factor (TF)-HRmRNA was constructed based on RNA-Seq, network pharmacology and TFs prediction. Exosome isolation and identification were performed using ultracentrifugation, NTA, TEM and western blot. Apoptosis and macrophage phenotypes were determined by flow cytometric analysis. Small RNA-Seq made exosomal miRNA identification. Small molecule interaction with targets were analyzed using molecular docking, SPR and CETSA. The direct relationship between transcription factors and promoters was verified using ChIP-QPCR and dual-luciferase reporter gene assay. A nude mice xenograft tumor model was established for vivo validation. HDI inhibited MKN45 cell proliferation, migration, invasion and promoted apoptosis. RNA-Seq identified 2583 HRmRNAs. PLXNC1 was screened out as the target HRmRNA associated with prognosis and M2 macrophage infiltration in GC. PLXNC1 promoted GC cell proliferation and facilitated TAMs M2 polarization by transferring GC cell-derived exosomal miR-92b-5p, inhibiting SOCS7-STAT3 interactions and subsequently activating STAT3 in macrophages. M2 TAMs induced by PLXNC1 -mediated GC cell-derived exosomes promoted GC cell migration and invasion. PLXNC1 regulated exosomal miR-92b-5p through the MEK1/MSK1/CREB1 pathway. STAT3 could transcriptionally regulate PLXNC1 expression in GC cells. The network of HDI constituent-hub TF-HRmRNA showed epigallocatechin gallate (EGCG) from HDI targeted STAT3 to transcriptionally regulate PLXNC1 expression. EGCG as a natural product directly bound to STAT3 to diminish its nuclear localization, resulting in the transcriptional repression of PLXNC1 and the reversal of M2 polarization induced by PLXNC1 -mediated GC cell-derived exosomes. PLXNC1 is a novel target exerting dual effects on GC cell proliferation and GC cell-mediated M2 polarization. EGCG derived from HDI inhibits GC cell proliferation and targets STAT3 to inhibit M2 polarization induced by PLXNC1 -mediated exosomes derived from GC cells, which may be a multi-target therapeutic agent for GC cell proliferation and immune microenvironment. [ABSTRACT FROM AUTHOR]

Fuelbreaks are used to manage wildfires worldwide. Regular mowing within fuelbreaks can alter species composition and transform them into grassland habitats. These changes may provide more herbaceous plants to large herbivores, subsequently influencing their distribution. To clarify the impact of fuelbreaks on herbivores' food resources, we conducted molecular dietary analysis to quantify the dietary composition of sika deer (Cervus nippon) in both the Sino-Russian border fuelbreak and forest interior, with an average distance of 1.6 km away from the fuelbreak. We constructed a local barcode database to enhance the resolution of the molecular dietary analysis. In addition, we surveyed the vegetation in these two habitats to determine the availability of food resources. We also used camera traps to monitor the visitation intensity of sika deer in both habitats. The results indicated that sika deer increased their visitation intensity at the fuelbreak during the snow-free season. The biomass of graminoids and herbaceous plants was high in the fuelbreak. However, the results of the molecular dietary analysis showed that during the snow-free season, the sika deer that visited the fuelbreak consumed fewer herbaceous plants. We used the Jacobs index to determine the dietary preferences of the sika deer and found that they were consistent browsers with a stable preference for woody plants. By assessing habitat quality, specifically the proportion of preferred plants, we found that the habitat quality of the fuelbreak was relatively low. In conclusion, fuelbreaks may attract herbivores. However, for browsers, such as sika deer, the major function of fuelbreaks is not to provide food resources. • Molecular dietary analysis reveals the diet of the sika deer. • Sika deer consistently prefer woody plants and they are browsers. • Fuelbreaks have a lower proportion of palatable plants for sika deer. • For browsers, the major function of fuelbreaks is not to provide food resources. • Sika deer increased their visits at the fuelbreak during the snow-free season. [ABSTRACT FROM AUTHOR]

Vulvovaginal candidiasis (VVC) is a common infection that affects the female reproductive tract. Pulsatilla decoction (PD), a traditional Chinese herbal medicine, is a classic and effective prescription for VVC. However, its mechanism of action remains unclear. This study aimed to evaluate the efficacy and potential mechanism of action of the n-butanol extract of Pulsatilla decoction (BEPD) in VVC treatment. High performance liquid chromatography (HPLC) was used to detect the main active ingredients in BEPD. A VVC-mouse model was constructed using an estrogen-dependent method to evaluate the efficacy of BEPD in VVC treatment. Fungal burden and morphology in the vaginal cavity were comprehensively assessed. Candida albicans -induced inflammation was examined in vivo and in vitro. The effects of BEPD on the Protein kinase Cδ (PKCδ) /NLR family CARD domain-containing protein 4 (NLRC4)/Interleukin-1 receptor antagonist (IL-1Ra) axis were analyzed using by immunohistochemistry (IHC), immunofluorescence (IF), western blot (WB), and reverse transcription–quantitative polymerase chain reaction (qRT-PCR). BEPD inhibited fungal growth in the vagina of VVC mice, preserved the integrity of the vaginal mucosa, and suppressed inflammatory responses. Most importantly, BEPD activated the "silent" PKCδ/NLRC4/IL-1Ra axis and negatively regulated NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome, thereby exerting a therapeutic efficacy on VVC. BEPD effects on mice with VVC were dose-dependent. BEPD protects against VVC by inhibiting inflammatory response and NLRP3 inflammasome via the activation of the PKCδ/NLRC4/IL-1Ra axis. This study revealed the pharmacological mechanism of BEPD in VVC treatment and provided further evidence for the application of BEPD in VVC treatment. [ABSTRACT FROM AUTHOR]

This research is focused on studying the effects of different dissolved organic matter (DOM) and electrolyte concentration on the Cd(II) adsorption on halloysite (HNT) surfaces. The DOM significantly decreased the Cd(II) adsorption by more than 25 %. Soil derived dissolved organic matter (SDT) showed the greatest negative impact, followed by humic acid (HA) and Fulvic acid (FA). The effects of background electrolytes NaCl and NH 4 Cl showed that both salts can undergo complexation with metals. Furthermore, the DOM (SDT/FA/HA) can cover the major HNT surface and the Cd(II) adsorption may occur due to outer-sphere complexation and ion exchange. Additionally, the influence of 100 mML−1 of NaCl on the aggregation tendencies of HNT has demonstrated that the presence of DOM amplifies the aggregation behavior of these nanotubes. The interaction energy barrier between HNT particles is dependent on physicochemical characteristics of DOM that inhibits Cd(II) sorption. These findings suggested that the HNT reduction, electrostatic repulsion and site-competition are the prominent mechanisms to decrease the Cd(II) immobilization on the HNT. The extent of Cd(II) adsorption/desorption on HNT surface followed the order of FA > HA > SDT/ HA > SDT > FA. • DOM's coverage on HNT surfaces leads to outer-sphere complexation, influencing Cd(II) adsorption dynamics. • NaCl induces the HNT-HNT aggregation. • The DOM modulates the interaction energy barrier between HNT particles, impacting Cd(II) sorption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dynamic model of the deer-tiger trophic chain, including grazing disturbance. • There may be a tipping point between grazing development and wildlife persistence. • The intensity and duration of overgrazing have different effects on tiger and deer population. • Providing insights for balancing livestock and wildlife conservation. The effects of grazing on wildlife have received considerable attention. Depending on factors such as its intensity and duration, grazing can impact higher-level species along the food chain through competition for available resources with wild herbivores. However, relatively few studies have investigated whether there are tipping points at which grazing intensity begins to seriously impact wildlife. In particular, studies that assess the impact of overgrazing on food chains that include carnivores remain scarce. We developed a time dynamic, age-structured model for the wild ungulates-Amur tiger trophic chain, including cattle grazing as a disturbance. We explored 1) the impact of cattle grazing intensity on the long-term behaviour of the wildlife population; 2) the effect of demographic parameters on wildlife population viability; and 3) the temporal dynamic impact of periods of heavy grazing on the population trajectory. Our results showed that increasing cattle density reaches a tipping point, triggering a rapid and significant shift in wildlife population size. Below the tipping point, wildlife can coexist with grazing livestock; when cattle density exceeds the tipping point, wild ungulate and tiger populations move towards extinction. In the case of heavy grazing, the dynamics of the wild ungulate population was more affected by its intensity, and the dynamics of the Amur tiger population was more affected by its duration. Our model and results suggest that theoretically wildlife conservation and cattle production can coexist but that serious regime shifts in wildlife populations may occur if grazing intensity exceeds a tipping point. These findings provide new insights useful for developing policies related to balancing livestock and wildlife conservation. [ABSTRACT FROM AUTHOR]

Valency, solubility and size of Fe are important controls on quality of natural waters. Recent recognition of the ubiquitous influence of natural organic matter on these, means that wider monitoring of Fe species in waters containing organic matter is required. We assess and develop methods that explicitly recognize this need. We show that for water samples prepared by acidification and filtration for inductively coupled plasma – atomic emission spectroscopy (I.C.P.-A.E.S.) analysis, only 50%–80% of Fe was recovered. This was because acidification coagulated the natural organic matter; Fe could then attach to its surface and/or be entrained as it deposited, both processes prevent Fe entering the I.C.P.-A.E.S. We show that this discrepancy in analysis of Fe – which could also occur and be more significant in analysis of trace metals - is likely to be undetected as the coagulate is unlikely to be observed prior to analysis. Accurate Fe analysis was possible, by I.C.P.-A.E.S. if H 2 O 2 and U.V. light were used to remove organic carbon (O.C.), or by use of proprietary Fe chelators that produce colored complexes (e.g. Palintest LR, Palintest, UK). We also show that reliable resolution of Fe(II) concentration into free Fe(II) and Fe(II) bound to O.C. can be achieved by monitoring the time taken for ferrozine color development. This occurs within 2 s for free Fe(II) but up to 3 days for Fe(II) bound to O.C. [Display omitted] • A standard method of aqueous metal analysis gives erroneously low results. • Acidification of water coagulates organic carbon preventing accurate analysis. • Coagulated organic carbon in acidified water samples is unlikely to be observed. • H 2 O 2 and U.V. light removes organic carbon allowing accurate metal analysis. • Determination of aqueous bound [FeII] is possible using ferrozine color development. [ABSTRACT FROM AUTHOR]

The sea cucumber Apostichopus japonicus is an economically important marine species in China, and understanding the mechanisms underlying its gonad development is crucial for successful reproduction and breeding. In this study, we performed transcriptome comparisons and analyses of A. japonicus gonadal and non-gonadal tissues to identify genes and molecular pathways associated with gonadal development. We also supplemented the annotation of the A. japonicus genome. Collectively, results revealed a total of 941 ovary-specific genes and 2499 testis-specific genes through different expression analysis and WGCNA analysis. The most enriched pathways in ovary and testis were "DNA replication" and "purine metabolism", respectively. Additionally, we identified key candidate gene modules that control gonad development and germ cell maturation, with CDT1 and DYNC2LI1 serving as hub genes. Our findings provide important insights into the gonadal development system of A. japonicus and offer valuable references for further research on reproductive biology in this marine invertebrate species. [Display omitted] • Comparative analyses of gene expression in sea cucumber gonadal and non-gonadal tissues • Key candidate gene modules specifically expressed by females and males gonad were screened. • The ovarian module with CDT1 as the core gene may affect ovarian development through the pre-replication complex. [ABSTRACT FROM AUTHOR]

Sporadic sightings of the endangered Amur tiger Panthera tigris altaica along the China-Russia border during the late 1990s sparked efforts to expand this subspecies distribution and abundance by restoring potentially suitable habitats in the Changbai Mountains. To guide science-based recovery efforts and provide a baseline for future monitoring of this border population, empirical, quantitative information is needed on what resources and management practices promote or limit the occurrence of tigers in the region. We established a large-scale field camera-trapping network to estimate tiger density, survival and recruitment in the Hunchun Nature Reserve and the surrounding area using an open population spatially explicit capture-recapture model. We then fitted an occupancy model that accounted for detectability and spatial autocorrelation to assess the relative influence of habitat, major prey, disturbance and management on tiger habitat use patterns. Our results show that the ranges of most tigers abut the border with Russia. Tiger densities ranged between 0.20 and 0.27 individuals/100 km 2 over the study area; in the Hunchun Nature Reserve, the tiger density was three times higher than that in the surrounding inland forested area. Tiger occupancy was strongly negatively related to heavy cattle grazing, human settlements and roads and was positively associated with sika deer abundance and vegetation cover. These findings can help to identify the drivers of tiger declines and dispersal limits and refine strategies for tiger conservation in the human-dominated transboundary landscape. Progressively alleviating the impacts of cattle and human disturbances on the forest, and simultaneously addressing the economic needs of local communities, should be key priority actions to increase tiger populations. The long-term goal is to expand tiger distribution by improving habitats for large ungulates. [ABSTRACT FROM AUTHOR]

The future of the critically endangered Amur leopard ( Panthera pardus orientalis ) is at a crucial point, and effective conservation strategies implemented within its primary historical range in Northeast China may determine the fate of this species. However, when a conservation plan was first developed for the species, scarce information on the leopards' status existed. To illustrate regional conservation challenges, we focused on the Hunchun Nature Reserve and the surrounding area along the China-Russia border, a potential stronghold for Amur leopard conservation. We conducted large-scale data analysis with a field camera-trapping network to present the first population estimates for this species using a spatially explicit capture–recapture approach. We then used a zero-inflated regression model to analyze the relationship of leopards with major prey species and anthropogenic disturbances. Our results indicate that leopards are returning to China, but most of them are part of a “border population” or are transient; their numbers are far too few to establish a healthy population. The spatial counts of leopards were noticeably high in areas with high prey richness and areas far from settlements and roads. Areas with few prey species and high human and cattle use exhibited a greater probability of “excess absences” of leopards. Mitigating human disturbances by progressively minimizing cattle and human impacts on the forest should be pursued along with habitat expansion for large ungulates, whose presence is essential for leopard occupancy. This study provides crucial information to support Chinese government recovery efforts and for refining conservation practices in human-dominated landscapes to ensure the long-term survival of this species. [ABSTRACT FROM AUTHOR]

Marine invertebrate aestivation is a unique strategy for summer survival in response to hot marine conditions. The sea cucumber, Apostichopus japonicus , is an excellent model marine invertebrate for studies of environmentally-induced aestivation. In the present study, we used a tandem mass tag (TMT)-coupled LC-MS/MS approach to identify and quantify the global proteome expression profile over the aestivation-arousal cycle of A. japonicus . A total of 3920 proteins were identified from the intestine of sea cucumber. Among them, 630 proteins showed significant differential expression when comparing three conditions of sea cucumbers: non-aestivating (active), deep-aestivation (at least 15 days of continuous aestivation), and arousal after aestivation (renewed moving and feeding). Sea cucumbers in deep aestivation showed substantial differentially expressed proteins (143 up-regulated and 267 down-regulated proteins compared with non-aestivating controls). These differentially expressed proteins suggested that protein and phospholipid probably are major fuel sources during hypometabolism and a general attenuation of carbohydrate metabolism was observed during deep aestivation. Differentially expressed proteins also provided the first global picture of a shift in protein synthesis, protein folding, DNA binding, apoptosis, cellular transport and signaling, and cytoskeletal proteins during deep aestivation in sea cucumbers. A comparison of arousal from aestivation with deep aestivation, revealed a general reversal of the changes that occurred in aestivation for most proteins. Western blot detection further validated the significant up-regulation of HSP70 and down-regulation of methyltransferase-like protein 7A-like in deep-aestivation. Our results suggest that there is substantial post-transcriptional regulation of proteins during the aestivation-arousal cycle in sea cucumbers. [ABSTRACT FROM AUTHOR]