Effects of polypropylene micro(nano)plastics on soil bacterial and fungal community assembly in saline-alkaline wetlands.

Microplastic pollution is a major environmental threat, especially to terrestrial ecosystems. To better understand the effects of microplastics on soil microbiota, the influence of micro- to nano-scale polypropylene plastics was investigated on microbial community diversity, functionality, co-occurrence, assembly, and their interaction with soil-plant using high-throughput sequencing approaches and multivariate analyses. The results showed that polypropylene micro/nano-plastics mainly reduced bacterial diversity, not fungal, and that plastic size had a stronger effect than concentration on the assembly of microbial communities. Nano-plastics decreased the complexity and connectivity of both bacterial and fungal networks compared to micro-plastics. Moreover, bacteria were more sensitive and deterministic to polypropylene micro/nano-plastic stress than fungi, as shown by their different growth rates, guanine-cytosine content, and cell structure. Interestingly, the dominant ecological process for bacteria shifted from stochastic drift to deterministic selection with polypropylene micro/nano-plastic exposure. Furthermore, nano-plastics directly or indirectly disrupted the interactions within intra-microbes and between soil-bacteria-plant by altering soil nutrients and stoichiometry (C:N:P) or plant diversity. Collectively, the results indicate that polypropylene nano-plastics pose more ecological risks to soil microbes and their plant-soil interactions. This study sheds light on the potential ecological consequences of polypropylene micro/nano-plastic pollution in terrestrial ecosystems.

Biochar addition can negatively affect plant community performance when altering soil properties in saline-alkali wetlands.

Biochar is a widely proposed solution for improving degraded soil in coastal wetland ecosystems. However, the impacts of biochar addition on the soil and plant communities in the wetland remains largely unknown. In this study, we conducted a greenhouse experiment using soil seed bank from a coastal saline-alkaline wetland. Three types of biochar, including Juglans regia biochar (JBC), Spartina alterniflora biochar (SBC) and Flaveria bidentis biochar (FBC), were added to the saline-alkaline soil at ratios of 1%, 3% and 5% (w/w). Our findings revealed that biochar addition significantly increased soil pH, and increased available potassium (AK) by 3.74% - 170.91%, while reduced soil salinity (expect for 3% SBC and 5%SBC) by 28.08% - 46.93%. Among the different biochar types, the application of 5% FBC was found to be the most effective in increasing nutrients and reducing salinity. Furthermore, biochar addition generally resulted in a decrease of 7.27% - 90.94% in species abundance, 17.26% - 61.21% in community height, 12.28% - 56.42% in stem diameter, 55.34% - 90.11% in total biomass and 29.22% - 78.55% in root tissue density (RTD). In particular, such negative effects was the worst in the SBC samples. However, 3% and 5% SBC increased specific root length (SRL) by 177.89% and 265.65%, and specific root surface area (SRSA) by 477.02% and 286.57%, respectively. The findings suggested that the plant community performance was primarily affected by soil pH, salinity and nutrients levels. Furthermore, biochar addition also influenced species diversity and functional diversity, ultimately affecting ecosystem stability. Therefore, it is important to consider the negative findings indirectly indicate the ecological risks associated with biochar addition in coastal salt-alkaline soils. Furthermore, Spartina alterniflora was needed to desalt before carbonization to prevent soil salinization when using S. alterniflora biochar, as it is a halophyte.

Long-term dietary exposure to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) reduced feeding in common carp (Cyprinus carpio): Via the JAK-STAT signaling pathway.

Polybrominated diphenyl ethers (PBDEs) are widely present in water ecosystems where they pose a significant threat to aquatic life, but our knowledge about how PBDEs affect feeding is limited. Therefore, this study explored the effects of continuous dietary exposure to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) (40 and 4000 ng/g) on the feeding in common carp (Cyprinus carpio) and the underlying mechanism. BDE-47 significantly decreased the food intake of carp. Transcriptome analysis of brain tissue showed that BDE-47 mainly affected the nervous, immune, and endocrine systems. Further examination of the expression levels of appetite factors in the brain revealed that BDE-47 caused dysregulation of appetite factors expressions such as agrp, pomc, cart, etc. In addition, the JAK-STAT signaling pathway was activated under BDE-47 exposure. It can be concluded from these findings that BDE-47 activated the JAK-STAT signaling pathway, causing imbalanced expression of appetite factors, leading to disordered feeding behavior and decreased food intake in carp. These results provide an important reference for a more comprehensive understanding of the hazards posed by BDE-47 on animal feeding and the associated mechanisms.

Nitrogen supply neutralizes the nanoplastic-plant interaction in a coastal wetland.

The presence of nanoplastics posed a potential threat to coastal saline-alkaline wetlands where nitrogen (N) fertilizer is being implemented as an important ecological restoration measure. Notwithstanding, the effects of N inputs on plant community in polypropylene-nanoplastics (PP-NPs) coexistence environments are largely unknown. To address this, we investigated the effects of PP-NPs addition alone or combined N supply on community aboveground biomass, morphological traits, diversity, composition, niche differentiation, interspecific interactions, and assembly. Our results showed that the PP-NPs addition alone reduced community aboveground biomass and morphological traits. However, the addition of high concentration (0.5%) PP-NPs alone favored community α-diversity and reduced community stability, which could be weakened through combined N supply. Overall, the effect of PP-NPs addition alone on plant community composition was greater than that of combined N supply. We also demonstrated PP-NPs addition alone and combined N supply reduced the niche breadth of the plant community and affected the niche overlap of dominant species. In the assembly of plant communities, stochastic processes played a dominant role. We conclude that N fertilization can amend the terrestrial nanoplastics pollution, thus mitigating the effects of PP-NPs on the plant community.

Distribution, source apportionment, and ecological risk assessment of soil antibiotic resistance genes in urban green spaces.

Urban green spaces play a crucial role in cities by providing near-natural environments that greatly impacts the health of residents. However, these green spaces have recently been scrutinized as potential reservoirs of antibiotic resistance genes (ARGs), posing significant ecological risks. Despite this concern, our understanding of the distribution, sources, and ecological risks associated with ARGs remains limited. In this study, we investigated the spatial distribution of soil ARGs using spatial interpolation and auto-correlation analysis. To apportion the source of soil ARGs in urban green spaces of Tianjin, Geo-detector method (GDM) was employed. Furthermore, we evaluated the ecological risk posed by ARGs employing risk quotients (RQ). The results of our study showed a significantly higher abundance of Quinolone resistance genes in the soil of urban green spaces in Tianjin. These genes were mainly found in the northwest, central, and eastern regions of the city. Our investigation identified three main factors contributing to the presence of soil ARGs: antibiotic production, precipitation, livestock breeding, and hospital. The results of ecological risk in RQ value showed a high risk associated with Quinolone resistance genes, followed by Aminoglycoside, Tetracycline, Multidrug, MLSB, Beta Lactam, Sulfonamide, and Chloramphenicol. Mantel-test and correlation analysis revealed that the ecological risk of ARGs was greatly influenced by soil properties and heavy metals. This study provides a new perspective on source apportionment and the ecological risk assessment of soil ARGs in urban green spaces.

Salvia miltiorrhiza polysaccharide promotes the health of crayfish (Procambarus clarkii) by promoting hemocyte phagocytosis, protecting hepatopancreas and enhancing intestinal barrier function.

Plant polysaccharides as immunomodulators are considered one of the effective measures to reduce antibiotic therapy in aquaculture. The immunomodulatory function of Salvia miltiorrhiza polysaccharides (SMP) has been demonstrated and begun to be applied in vertebrates, but its potential effect on crustaceans is unclear. In this study, crayfish (Procambarus clarkii) was fed with 0 %, 0.3 %, 0.7 %, 1.1 %, and 1.5 % SMP for 4 weeks to investigate the effects of SMP on hemocytes phagocytosis, hepatopancreatic function, and intestinal barrier function. The results revealed that hemocyte phagocytic activity was increased in all SMP groups. During the process of hemocytes phagocytic recognition and formation of phagosomes and phagolysosomes, the mRNA expression levels of mas, hem, rab3, ctsb, and lamp-1 were up-regulated mainly in the 0.3 % SMP group. During the clearance phase of phagocytosis, respiratory burst activity, ROS level, T-SOD, CAT, GST, and LZM activities were mainly increased in the 1.5 % SMP group. Hepatopancreas AKP and GOT activity were no significant change in all SMP groups. ACP activity was significantly enhanced in the 1.1 % SMP group. The GPT activity of 0.3-0.7 % SMP group was significantly decreased. The 0.7 % SMP group had the highest intestinal fold height. The highest index values of OTUs, Ace, Chao, and Shannon were in the 0.3 % SMP group. The dietary addition of 0.3 % SMP led to a tendency of increased relative abundance of Firmicutes and Bacteroidota at the phylum level, while the relative abundance of Proteobacteria at the phylum level decreased. In conclusion, dietary SMP could promote crayfish health by enhancing phagocytosis, protecting hepatopancreas and enhancing intestinal barrier function. This study contributes to the theoretical foundation for exploring the potential application of plant polysaccharides in crustaceans.

Luminescent polypeptides.

Polypeptides, as biomacromolecules, hold immense potential in various biological applications such as tissue engineering, immunomodulating agents, and target binding. Among these applications, the attention towards luminescent polypeptides has grown significantly, due to their ability to visualize biological processes effectively. In this perspective, we have compiled information on three distinct types of luminescent polypeptides: natural fluorescent proteins, luminophores-bioconjugated polypeptides, and synthesized polypeptides with clusteroluminescence. Last, we shed light on the significance and prospects of clusteroluminescent polypeptides, which are expected to emerge as crucial new-generation bioluminophores, offering high emission efficiency and tunable emission wavelengths.

Microplastics could alter invasive plant community performance and the dominance of Amaranthus palmeri.

The increase in alien plant invasions poses a major threat to global biodiversity and ecosystem stability. However, the presence of microplastics (MPs) as an environmental stressor could impact the interactions between invasive and native species in an invasive plant community. Nevertheless, the community alterations and underlying mechanisms resulting from these interactions remain unclear. Herein, we systematically investigated the impacts of polyethylene (PE) and polypropylene (PP) on invasive plant communities invaded by Amaranthus palmeri through soil seed bank. The results illustrated that MPs markedly declined community height and biomass, and altered community structure, low-dose MPs could prominently increase community invasion resistance, but reduced community stability. The niche width and niche overlap of A. palmeri and S. viridis declined when exposed to high-dose MPs, but MPs elicited a significant rise in the niche width of S. salsa. PP had the potential to reduce the diversity of invasive plant community. Structural equation model revealed that PP addition could change soil total phosphorus content, thereby leading to a reduction of the community stability. Our study helps to fill the knowledge gap regarding the effects of MPs on invasive plant communities and provide new perspectives for invasive plant management.

Biochar may alter plant communities when remediating the cadmium-contaminated soil in the saline-alkaline wetland.

It is thought remediating cadmium pollution with biochar can affect plant traits. However, the potential impact of this practice on plant communities is poorly understood. Here, we established natural-germinated plant communities using soil seed bank from a saline-alkaline wetland and applied a biochar treatment in Cd-polluted wetland soil. The outcomes illustrated that Juglans regia biochar (JBC), Spartina alterniflora biochar (SBC), and Flaveria bidentis biochar (FBC) promoted exchangeable Cd transform into FeMn oxide bound Cd. Additionally, most biochar addition reduced species abundance, root-shoot ratio, biomass, diversity, and community stability, yet enhanced community height. Among all treatments, the 5 % SBC demonstrated the most significant reduction in species abundance, biomass, species richness and functional richness. Specifically, it resulted in a reduction of 92.80 % in species abundance, 73.80 % in biomass, 66.67 % in species richness, and 95.14 % in functional richness compared to the CK. We also observed changes in root morphological traits and community structure after biochar addition. Soil pH, salinity, and nutrients played a dominant role in shaping plant community. These findings have implications for biodiversity conservation, and the use of biochar for the remediation of heavy metals like cadmium should be approached with caution due to its potential negative impacts on plant communities.

The Diagnostic Value of Triggering Receptor Expressed on Myeloid Cells-1 in Post-Traumatic Bacterial Endophthalmitis.

Purpose: To determine whether soluble-triggering receptor expressed on myeloid cells-1 (sTREM-1) could serve as a reliable diagnostic biomarker of post-traumatic bacterial endophthalmitis (PTBE). Methods: Thirty-two patients (32 eyes) clinically diagnosed having PTBE were further divided into a culture-positive (CP) group and a culture-negative (CN) group. Sixty-two patients (62 eyes) without traumatic endophthalmic infection were also enrolled. Twenty-one eyes from 11 donors without globe ocular injuries were included as control group. Vitreous sTREM-1 levels were detected by ELISA. The expression and tissue distribution of TREM-1 were revealed by immunohistochemistry. The diagnostic value of sTREM-1 was determined by receiver operating characteristic curve (ROC). The correlation between sTREM-1 concentration and final best-corrected visual acuity (FBCVA) and Peyman endophthalmitis score (PES) were also assessed. Results: The vitreous sTREM-1 level in the PTBE group was higher than that in noninfected group and control group (P < 0.05). No remarkable difference was found between the CP group and the CN group in vitreous sTREM-1 levels (P > 0.05). No remarkable difference was found between the noninfected group and the control group (P > 0.05). No remarkable difference in TREM-1 level was found before and after intravitreal antibiotics (P > 0.05). TREM-1 was selectively highly expressed on the surface of cell membrane of neutrophils and monocytes/macrophages infiltrated in vitreous and uveal of the PTBE group. The area under the ROC curve (AUC) was 0.79 (>0.75), with a medium diagnostic efficiency. The sensitivity and specificity of sTREM-1 to differentiate PTBE from the noninfected intraocular condition were 62.50% and 86.25% separately. A cutoff value >524.50 pg/mL for sTREM-1 was predicted to be PTBE. Vitreous sTREM-1 levels in PTBE group were positively correlated with PES (r = 0.428, P < 0.05). However, sTREM-1 levels and FBCVA did not significantly correlate with one another (P > 0.05). Conclusions: The sTREM-1 was a promising diagnostic biomarker of PTBE, especially CN-PTBE. Vitreous sTREM-1 levels were linked with intraocular inflammation levels and severity of PTBE.

Doxycycline Suppresses Vasculogenic Mimicry in Human Pterygium Fibroblasts.

PURPOSE: To explore the effect of doxycycline on vasculogenic mimicry (VM) formation and the potential mechanism in human pterygium fibroblasts in order to find novel targets for pterygium therapy. METHODS: First, we demonstrate the existence of VM in 73 pterygium specimens by CD31 and periodic acid Schiff (PAS) dual staining. Then we used cell counting kit-8, clone formation assay and flow cytometry to prove the inhibitory effect of doxycycline on cell proliferation and apoptosis. The VM formation was evaluated through wound healing assay, cell transwell assay and three-dimensional cell culture combined with PAS staining. Finally, we used Western blot to testify the correlation of the VM and the factors in protein level preliminarily. RESULTS: Our results showed that VM existed in human pterygium specimens exactly. Otherwise, in human pterygium fibroblasts, doxycycline induced a dose-dependent inhibitory effect on cell proliferation and apoptosis induction. Besides, doxycycline significantly suppressed vasculogenic mimicry tube formation, cell migration and invasion. Furthermore, doxycycline impaired the expression of MMP-9, MMP-2 and VEGF which may related to pterygium VM formation. CONCLUSIONS: Doxycycline decelerated pterygium progression might be through inhibiting VM formation according to the downregulation of MMP-9, MMP-2 and VEGF, which may provide the basis of further studies involving doxycycline for pterygium treatment.

Temporal-spatial change of China's coastal ecosystems health and driving factors analysis.

Understanding the spatial distribution pattern change and driving factors behind ecosystem health is essential to ecosystem management and restoration. However, in the research of regional ecosystem health, there is little research on ecosystem health in coastal regions, and there is little exploration of its temporal and spatial pattern change and its driving factors. In this study, we use the Vigor-Organization-Resilience-Services (VORS) model and marine ecosystem health index to diagnose the ecosystem health of the whole coastal area of China over the last 20 years, and find the main contributing factors affecting ecosystem health with the help of geographic detectors and geographic weighted regression analysis. Our results show that: (1) the ecosystem health level in the south of the coastal region is higher than that in the north, mainly with 30° north latitude as the main dividing line. (2) The regions with high change rate are mainly concentrated in Bohai Bay, the Yangtze River Estuary, Hangzhou Bay and the Pearl River Estuary, and the change is mainly negative. (3) Both natural and human factors have an impact on ecosystem health, and the influencing factors are different on different scales. The interaction between different factors is greater than the impact of a single factor on ecosystem health. The study puts forward a new evaluation framework for the study of ecosystem health in coastal areas, which can be applied to other coastal areas with similar conditions, and can help the sustainable and healthy development of coastal areas.

In-depth analysis of eight susceptibility loci of primary angle closure glaucoma in Han Chinese.

Primary angle closure glaucoma (PACG) is a multifactorial disease with genetic predisposition. Primary angle closure (PAC) is the early stage of PACG and they share the same anatomical characteristics. We aimed to examine whether the PACG associated-genetic loci identified previously by genome-wide association study (GWAS) were also related to primary angle closure disease (PACD) in Han Chinese. This cross-sectional case-control study consisted of 232 PAC, 264 PACG and 306 controls. Eight single-nucleotide polymorphisms (SNPs) of PACG susceptibility loci within PLEKHA7, COL11A1, PCMTD1-ST18, EPDR1, CHAT, GLIS3, FERMT2, DPM2-FAM102A were genotyped using participants' blood samples. We excluded 3 SNPs for PAC analysis because the data has been reported using the same sample set. Anatomical parameters such as axial length (AL), anterior chamber depth (ACD) and lens thickness (LT) were included as phenotypes for the association analysis. Allelic and genotypic model tests were performed. Three among the eight SNPs were found to be significantly associated with PACG, e.g. PLEKHA7 rs11024102 in additive, dominant and recessive model; and both CHAT rs1258267 and DPM2-FAM102A rs3739821 in dominant model. CHAT rs1258267 showed marginal association with PAC in dominant model. Anatomical parameters were not found to link to the eight SNPs after Bonferroni multiple test correction. Our data suggest that PLEKHA7 and DPM2-FAM102A might exert effect in the late stage of the PACD, while CHAT may play a broad role in both early and late stages of the PACD.

Analysis on Soil Seed Bank Diversity Characteristics and Its Relation with Soil Physical and Chemical Properties after Substrate Addition.

AIMS: Considered as an essential measure in the application of soil seed bank (SSB) projects, the mixing of substrate and surface soil can effectively improve soil condition. This research is aimed at exploring the diversity characteristics of SSBs and the relationships between SSBs and soil properties. METHODS: Canonical correspondence analysis (CCA) was adopted to describe the ordination of SSBs on soil properties' gradients; multiple linear regressions were adopted to analyze the relationship between average growth height and soil properties, density and soil properties. RESULTS: Experimental groups of mixed substrate (the mixture of organic and inorganic substrates) had high diversity indexes, especially the Shannon-Wiener Index compared with those of single substrate. Meanwhile, a higher number of species and increased density were also noted in those of mixed substrate. The best test group, No.16, had the highest diversity indexes with a Shannon-Wiener of 1.898, Simpson of 0.633 and Pielou of 0.717, and also showed the highest density of 14000 germinants /m2 and 21 species. In addition, an improvement of the soil's chemical and physical properties was noted when the substrates were mixed. The mixed substrate of turfy soil and perlite could effectively enhance the soil moisture content, whilst a mixed substrate of rice husk carbon and vermiculite could improve the content of available potassium (AK) and phosphorus (AP) and strengthen soil fertility. The germinated plants also reflected obvious regularities of ordination on soil factor gradients. Three distinct cluster groups were presented, of which the first cluster was distributed in an area with a relatively higher content of AK and AP; the second cluster was distributed at places with relatively higher soil moisture content; and the third cluster of plants didn't show any obvious relationship with soil physical and chemical properties. Through CCA analysis, AK and AP were considered the most important soil factors to influence the SSB, which was illustrated in regression analysis with a high correlation coefficient when dependent values were growth height and density respectively. The linear regression equations with: growth height = 142.728 - 1.514TC + 30.218AP - 5.083TN + 10.839AK + 1.234mc; density = -68.216 - 4.609TC + 9.566AP - 35.492TN + 19.779AK - 1.591mc.were established by multiple linear regression. CONCLUSIONS: (1) The mixed substrates showed a greater advantage for SSBs than single substrates, both in improving the number of species, density and diversity indexes. (2) The germinated plants reflected an obvious preference to different soil conditions, which different mixed substrates could improve accordingly. (3) AK, AP were important soil factors to influence SSBs, especially in the growth of plants and density.

[Optimization of application parameters of soil seed bank in vegetation recovery via response surface methodology].

The thickness of surface soil, the covering thickness and the number of adding arbor seeds are all important factors to be considered in the application of soil seed bank (SSB) for vegetation recovery. To determine the optimal conditions, the Box-Behnken central composite design with three parameters and three levels was conducted and Design-Expert was used for response surface optimization. Finally, the optimal model and optimal level of each parameter were selected. The quadratic model was more suitable for response surface optimization (P < 0.0001), indicating the model had good statistical significance which could express ideal relations between all the independent variable and dependent variable. For the optimum condition, the thickness of surface soil was 4.3 cm, the covering thickness was 2 cm, and the number of adding arbor seeds was 224 ind x m(-2), under which the number of germinated seedlings could be reached up to 6222 plants x m(-2). During the process of seed germination, significant interactions between the thickness of surface soil and the covering thickness, as well as the thickness of surface soil and the number of adding arbor seeds were found, but the relationship between the covering thickness and the number of adding arbor seeds was relatively unremarkable. Among all the parameters, the thickness of surface soil was the most important one, which had the steepest curve and the largest standardized coefficient.