ACSL4 accelerates osteosarcoma progression via modulating TGF-ß/Smad2 signaling pathway.

Osteosarcoma (OS) is a malignant bone sarcoma arising from mesenchymal stem cells. The biological role of Acyl-CoA synthetase long-chain family member 4 (ACSL4), recently identified as an oncogene in numerous tumor types, remains largely unclear in OS. In this study, we investigated the expression of ACSL4 in OS tissues using immunohistochemistry staining (IHC) staining of a human tissue microarray and in OS cells by qPCR assay. Our findings revealed a significant up-regulation of ACSL4 in both OS tissues and cells. To further understand its biological effects, we conducted a series of loss-of-function experiments using ACSL4-depleted MNNG/HOS and U-2OS cell lines, focusing on OS cell proliferation, migration, and apoptosis in vitro. Our results demonstrated that ACSL4 knockdown remarkably suppressed OS cell proliferation, arrested cells in the G2 phase, induced cell apoptosis, and inhibited cell migration. Additionally, a subcutaneous xenograft mice model was established to validate the in vivo impact of ACSL4, revealing ACSL4 silencing impaired tumor growth in the OS xenograft mice. Additionally, we discovered that ACSL4 could regulate the phosphorylation level of Smad2 through cooperative interactions, and treatment with a TGF-ß inhibitor weakened the promoting effects of ACSL4 overexpression. In short, ACSL4 regulated OS progression by modulating TGF-ß/Smad2 signaling pathway. These findings underscore ACSL4 as a promising therapeutic target for OS patients and contribute novel insights into the pathogenesis of OS.

Translational Pharmacokinetic/Pharmacodynamic Modeling and Simulation of Oxaliplatin and Irinotecan in Colorectal Cancer.

Despite the recent advances in this field, there are limited methods for translating organoid-based study results to clinical response. The goal of this study was to develop a pharmacokinetic/pharmacodynamic (PK/PD) model to facilitate the translation, using oxaliplatin and irinotecan treatments with colorectal cancer (CRC) as examples. The PK models were developed using qualified oxaliplatin and irinotecan PK data from the literature. The PD models were developed based on antitumor efficacy data of SN-38 and oxaliplatin evaluated in vitro using tumor organoids. To predict the clinical response, translational scaling of the models was established by incorporating predicted ultrafiltration platinum in plasma or SN-38 in tumors to PD models as the driver of efficacy. The final PK/PD model can predict PK profiles and responses following treatments with oxaliplatin or irinotecan. After generation of virtual patient cohorts, this model simulated their tumor shrinkages following treatments, which were used in analyzing the efficacies of the two treatments. Consistent with the published clinical trials, the model simulation suggested similar patient responses following the treatments of oxaliplatin and irinotecan with regards to the probabilities of progression-free survival (HR = 1.05, 95%CI [0.97;1.15]) and the objective response rate (OR = 1.15, 95%CI [1.00;1.32]). This proposed translational PK/PD modeling approach provides a significant tool for predicting clinical responses of different agents, which may help decision-making in drug development and guide clinical trial design.

The influence of metoprolol in patients with sepsis-induced cardiomyopathy: A retrospective study.

OBJECTIVES: To focus on evaluating the clinical influence of metoprolol on sepsis-induced cardiomyopathy (SICM). METHODS: A total of 90 patients with SICM was enrolled from December 2018 to February 2021 and divided into 2 groups according to the use of metoprolol during hospitalization in Suzhou Municipal Hospital in Suzhou, China. We compared them with the cardiac function, sequential organ failure assessment score, and clinical outcomes. RESULTS: Between the 2 groups, the oxygenation indices and Glasgow coma scale in the metoprolol group were higher on the first day of treatment, with Glasgow coma scale higher on the third day of treatment. However, the doses of norepinephrine in patients with metoprolol showed no significant differences with the control group. The all-causemortality at 28 days in the metoprolol group was lower, and the time of removing from ventilator support as well as the number of failured organs also significantly differed between the 2 groups. CONCLUSION: Metoprolol can reduce the 28-day mortality and shorten the duration of mechanical ventilation in SICM. It can also reduce the number of organ failures and improve the oxygenation index and Glasgow coma scale of these patients. Meanwhile, metoprolol did not affect the norepinephrine dose in patients with SICM.

Fittings Detection Method Based on Multi-Scale Geometric Transformation and Attention-Masking Mechanism.

Overhead transmission lines are important lifelines in power systems, and the research and application of their intelligent patrol technology is one of the key technologies for building smart grids. The main reason for the low detection performance of fittings is the wide range of some fittings' scale and large geometric changes. In this paper, we propose a fittings detection method based on multi-scale geometric transformation and attention-masking mechanism. Firstly, we design a multi-view geometric transformation enhancement strategy, which models geometric transformation as a combination of multiple homomorphic images to obtain image features from multiple views. Then, we introduce an efficient multiscale feature fusion method to improve the detection performance of the model for targets with different scales. Finally, we introduce an attention-masking mechanism to reduce the computational burden of model-learning multiscale features, thereby further improving model performance. In this paper, experiments have been conducted on different datasets, and the experimental results show that the proposed method greatly improves the detection accuracy of transmission line fittings.

[Guiding value of dynamic monitoring citrulline for early enteral nutrition in patients with severe gastrointestinal injury].

OBJECTIVE: To investigate whether dynamic monitoring of citrulline (Cit) has guiding value for early enteral nutrition (EN) in patients with severe gastrointestinal injury. METHODS: A observational study was conducted. A total of 76 patients with severe gastrointestinal injury admitted to different intensive care units of Suzhou Hospital Affiliated to Nanjing Medical University from February 2021 to June 2022 were enrolled. Early EN was performed in 24-48 hours after admission as recommended by the guidelines. Those who did not terminate EN after 7 days were enrolled in the early EN success group, and those who terminated EN within 7 days due to persistent feeding intolerance or deterioration of general condition were enrolled in the early EN failure group. There was no intervention during the treatment. Serum Cit levels were measured by mass spectrometry at admission, before EN starting and EN 24 hours, respectively, and the changes in Cit within EN 24 hours (ΔCit) were calculated (ΔCit = EN 24-hour Cit-Cit before EN starting). Receiver operator characteristic curve (ROC curve) was plotted to investigate the predictive value of ΔCit for early EN failure, and the optimal predictive value was calculated. Multivariate unconditional Logistic regression was used to analyze the independent risk factors for early EN failure and death at 28 days. RESULTS: Seventy-six patients were enrolled in the final analysis, of which 40 succeeded in early EN and 36 failed. There were significant differences in age, main diagnosis, acute physiology and chronic health evaluation II (APACHE II) score at admission, blood lactic acid (Lac) before EN initiation and ΔCit between the two groups. Multivariate Logistic regression analysis showed that age [odds ratio (OR) = 0.929, 95% confidence interval (95%CI) was 0.874-0.988, P = 0.018], ΔCit (OR = 2.026, 95%CI was 1.322-3.114, P = 0.001) and increased feeding rate within 48 hours (OR = 13.719, 95%CI was 1.795-104.851, P = 0.012) were independent risk factors for early EN failure in patients with severe gastrointestinal injury. ROC curve analysis showed that ΔCit had a good predictive value for early EN failure in patients with severe gastrointestinal injury [area under the ROC curve (AUC) = 0.787, 95%CI was 0.686-0.887, P < 0.001], and the optimal predictive value of ΔCit was 0.74 µmol/L (sensitivity was 65.0%, specificity was 75.0%). Combined with the optimal predictive value of ΔCit, "overfeeding" was defined as ΔCit < 0.74 µmol/L and increased feeding within 48 hours. Multivariate Logistic regression analysis showed that age (OR = 0.825, 95%CI was 0.732-0.930, P = 0.002), APACHE II score (OR = 0.696, 95%CI was 0.518-0.936, P = 0.017) and early EN failure (OR = 181.803, 95%CI was 3.916-8 439.606, P = 0.008) were independent risk factors for 28-day death in patients with severe gastrointestinal injury. The new variable "overfeeding" was also associated with an increased risk of death at 28 days (OR = 27.816, 95%CI was 1.023-755.996, P = 0.048). CONCLUSIONS: Dynamic monitoring of Cit has guiding value for early EN in patients with severe gastrointestinal injury.

Phosphorylation-dependent recognition of diverse protein targets by the cryptic GK domain of MAGI MAGUKs.

Dynamic signal transduction requires the rapid assembly and disassembly of signaling complexes, often mediated by phosphoprotein binding modules. The guanylate kinase-like (GK) domain of the membrane-associated guanylate kinases (MAGUKs) is such a module orchestrating signaling at cellular junctions. The MAGI subfamily of MAGUKs contains a truncated GK domain with unknown structure and function, although they participate in diverse physiological and pathological processes. Here, we demonstrate that the truncated GK domain of MAGI2 interacts with its adjacent PDZ0 domain to form a structural supramodule capable of recognizing phosphoproteins. A conserved phosphorylation-dependent binding motif for PDZ0-GK is delineated, which leads to identification of a set of previously unknown binding partners. We explore the structure and function of the MAGI2-target complex with an inhibitory peptide derived from the consensus motif. Our work reveals an action mechanism of the cryptic MAGI GKs and broadens our understanding of the target recognition rules of phosphoprotein binding modules.

[Research of epigallocatechin gallate in delaying chondrocyte senescence].

Objective: To investigate the effect of epigallocatechin gallate (EGCG) on chondrocyte senescence and its mechanism. Methods: The chondrocytes were isolated from the articular cartilage of 4-week-old Sprague Dawley rats, and cultured with type Ⅱcollagenase and passaged. The cells were identified by toluidine blue staining, alcian blue staining, and immunocytochemical staining for type Ⅱ collagen. The second passage (P2) cells were divided into blank control group, 10 ng/mL IL-1ß group, and 6.25, 12.5, 25.0, 50.0, 100.0, and 200.0 µmol/L EGCG+10 ng/mL IL-1ß group. The chondrocyte activity was measured with cell counting kit 8 after 24 hours of corresponding culture, and the optimal drug concentration of EGCG was selected for the subsequent experiment. The P2 chondrocytes were further divided into blank control group (group A), 10 ng/mL IL-1ß group (group B), EGCG+10 ng/mL IL-1ß group (group C), and EGCG+10 ng/mL IL-1ß+5 mmol/L 3-methyladenine (3-MA) group (group D). After cultured, the degree of cell senescence was detected by ß-galactosidase staining, the autophagy by monodansylcadaverine method, and the expression levels of chondrocyte-related genes [type Ⅱ collagen, matrix metalloproteinase 3 (MMP-3), MMP-13] by real-time fluorescent quantitative PCR, the expression levels of chondrocyte-related proteins (Beclin-1, LC3, MMP-3, MMP-13, type Ⅱ collagen, P16, mTOR, AKT) by Western blot. Results: The cultured cells were identified as chondrocytes. Compared with the blank control group, the cell activity of 10 ng/mL IL-1ß group significantly decreased ( P<0.05). Compared with the 10 ng/mL IL-1ß group, the cell activity of EGCG+10 ng/mL IL-1ß groups increased, and the 50.0, 100.0, and 200.0 µmol/L EGCG significantly promoted the activity of chondrocytes ( P<0.05). The 100.0 µmol/L EGCG was selected for subsequent experiments. Compared with group A, the cells in group B showed senescence changes. Compared with group B, the senescence rate of chondrocytes in group C decreased, autophagy increased, the relative expression of type Ⅱ collagen mRNA increased, and relative expressions of MMP-3 and MMP-13 mRNAs decreased; the relative expressions of Beclin-1, LC3, and type Ⅱ collagen proteins increased, but the relative expressions of P16, MMP-3, MMP-13, mTOR, and AKT proteins decreased; the above differences were significant ( P<0.05). Compared with group C, when 3-MA was added in group D, the senescence rate of chondrocytes increased, autophagy decreased, and the relative expressions of the target proteins and mRNAs showed an opposite trend ( P<0.05). Conclusion: EGCG regulates the autophagy of chondrocytes through the PI3K/AKT/mTOR signaling pathway and exerts anti-senescence effects.

Intermediate role of gut microbiota in vitamin B nutrition and its influences on human health.

Vitamin B consists of a group of water-soluble micronutrients that are mainly derived from the daily diet. They serve as cofactors, mediating multiple metabolic pathways in humans. As an integrated part of human health, gut microbiota could produce, consume, and even compete for vitamin B with the host. The interplay between gut microbiota and the host might be a crucial factor affecting the absorbing processes of vitamin B. On the other hand, vitamin B supplementation or deficiency might impact the growth of specific bacteria, resulting in changes in the composition and function of gut microbiota. Together, the interplay between vitamin B and gut microbiota might systemically contribute to human health. In this review, we summarized the interactions between vitamin B and gut microbiota and tried to reveal the underlying mechanism so that we can have a better understanding of its role in human health.

[Carbon Dioxide Mitigation Co-effect Analysis of Structural Adjustment Measures in the "2+26" Cities in the Jing-Jin-Ji Region and Its Surroundings].

The Three-Year Action Plan for Winning the Blue Sky Defense Battle states that structural adjustments of industrial, energy, transportation, and land use are important to significantly reduce CO2 and air pollutant emissions. This co-effect is evident but has not been quantified at the city-cluster level. This study developed an emission inventory for the "2+26" cities of the Jing-Jin-Ji region and its surroundings and quantitatively analyzed the impacts of measures in the Three-Year Action Plan for Winning the Blue Sky Defense Battle on the emissions of CO2 and major air pollutants using Greenhouse Gas and Air Pollution Interactions and Synergies in the "2+26" cities model (GAINS-JJJ). The results showed that in the "2+26" cities, the emission reductions in CO2, primary PM2.5, SO2, NOx, and NH3 under policy scenario 2020 were 29.1 Mt (equivalent to 2% of the emissions in 2017), 203.8 (21%), 281.8 (27%), 485.5 (17%), and 34.3 kt (3%), respectively, relative to 2017. In terms of the cities or sectors, the higher the pollutant emissions, the higher the reduction achieved. The CO2 mitigation co-effect results showed that industrial adjustment measures, such as eliminating backward production capacity, upgrades on industrial boilers, and phasing out small and polluting factories, contributed the most to the co-effect of CO2 emission reduction, whereas NOx presented the highest co-effects, with CO2 among the different air pollutants.

Construction of a synthetic methodology-based library and its application in identifying a GIT/PIX protein-protein interaction inhibitor.

In recent years, the flourishing of synthetic methodology studies has provided concise access to numerous molecules with new chemical space. These compounds form a large library with unique scaffolds, but their application in hit discovery is not systematically evaluated. In this work, we establish a synthetic methodology-based compound library (SMBL), integrated with compounds obtained from our synthetic researches, as well as their virtual derivatives in significantly larger scale. We screen the library and identify small-molecule inhibitors to interrupt the protein-protein interaction (PPI) of GIT1/ß-Pix complex, an unrevealed target involved in gastric cancer metastasis. The inhibitor 14-5-18 with a spiro[bicyclo[2.2.1]heptane-2,3'-indolin]-2'-one scaffold, considerably retards gastric cancer metastasis in vitro and in vivo. Since the PPI targets are considered undruggable as they are hard to target, the successful application illustrates the structural specificity of SMBL, demonstrating its potential to be utilized as compound source for more challenging targets.

Altered active pyrene degraders in biosurfactant-assisted bioaugmentation as revealed by RNA stable isotope probing.

Bioaugmentation is an effective approach for removing pyrene from contaminated sites, and its performance is enhanced by a biosurfactant. To reveal the mechanisms of biosurfactant-assisted bioaugmentation, we introduced RNA stable isotope probing (RNA-SIP) in the pyrene-contaminated soils and explored the impacts of rhamnolipid on the pyrene degradation process. After 12-day degradation, residual pyrene was the lowest in the bioaugmentation treatment (7.76 ± 1.57%), followed by biosurfactant-assisted bioaugmentation (9.86 ± 2.58%) and enhanced natural attenuation (23.97 ± 1.05%). Thirteen well-known and two novel pyrene-degrading bacteria were confirmed to participate in the pyrene degradation. Pyrene degradation was accelerated in the biosurfactant-assisted bioaugmentation, manifested by the high diversity of active pyrene degraders. Our findings expand the knowledge on pyrene degrading bacteria and the mechanisms of pyrene degradation in a bioaugmentation process.

Promotion of row 1-specific tip complex condensates by Gpsm2-Gαi provides insights into row identity of the tallest stereocilia.

The mechanosensory stereocilia in hair cells are organized into rows of graded height, a property crucial for auditory perception. Gpsm2-Gαi-Whirlin-Myo15-Eps8 complex at tips of the tallest stereocilia is proposed to define hair bundle row identity, although the underlying mechanism remains elusive. Here, we find that Gpsm2 could undergo phase separation. Moreover, row 1-specific Gpsm2-Gαi complex significantly promotes the formation of the five-component tip complex density (5xTCD) condensates. The 5xTCD condensates display much stronger actin-bundling ability than those without Gpsm2-Gαi, which may provide critical insights into how Gpsm2-Gαi specifies the tallest stereocilia. A deafness-associated mutation of Gpsm2 leads to impaired formation of the 5xTCD condensates and consequently reduced actin bundling, providing possible clues for etiology of hearing loss in patients with Chudley-McCullough syndrome.

A Qualitative Signature to Identify TERT Promoter Mutant High-Risk Tumors in Low-Grade Gliomas.

Background: Telomerase reverse transcriptase promoter (TERT-p) mutation has been frequently found, but associated with contrary prognosis, in both low-grade gliomas and glioblastomas. For the low-grade gliomas (Grades II-III), TERT-p mutant patients have a better prognosis than the wildtype patients, whereas for the GBMs (Grade IV), TERT-p mutation is related to a poor prognosis. We hypothesize that there exist high-risk patients in LGGs who share GBM-like molecular features, including TERT-p mutation, and need more intensive treatment than other LGGs. A molecular signature is needed to identify these high-risk patients for an accurate and timely treatment. Methods: Using the within-sample relative expression orderings of gene pairs, we identified the gene pairs with significantly stable REOs, respectively, in both the TERT-p mutant LGGs and GBMs but with opposite directions in the two groups. These reversely stable gene pairs were used as the molecular signature to stratify the LGGs into high-risk and low-risk groups. Results: A signature consisting of 21 gene pairs was developed, which can classify LGGs into two groups with significantly different overall survival. The high-risk group has a similar genetic mutation profile and a similar survival profile as GBMs, and these high-risk tumors may progress to a more malignant state. Conclusion: The 21 gene-pair signature based on REOs is capable of identifying high-risk patients in LGGs and guiding the clinical choice for appropriate and timely intervention.

Efficient Catalysts of K and Ce Co-Doped LaMnO3 for NO x -Soot Simultaneous Removal and Reaction Kinetics.

Presently, the treatment of four-way catalysts is important for reducing pollutant emissions from diesel engine exhaust, which is a major cause of urban haze. In this study, we prepared perovskite-type catalysts via the citric acid sol-gel method. Experiment results showed that K substitution at site A in LaMnO3 decreased the agglomeration of the catalysts effectively, increased the contact with the reaction gas, promoted the conversion of Mn3+ → Mn4+, and reduced the ignition temperature of soot. Ce substitution at the B-site in La0.5K0.5MnO3 produced a CeO2 phase and decreased the Mn4+/Mn3+ ratio to 0.49, which is conducive to improving the catalytic oxidation performance. The K and Ce co-doping had the best activation effect, which showed a low activation energy (10.87 KJ mol-1) and a high simultaneous removal rate of NO x (reaching 90% at 275 °C) and soot ignition at 250 °C under lean conditions.

Phase Separation of MAGI2-Mediated Complex Underlies Formation of Slit Diaphragm Complex in Glomerular Filtration Barrier.

BACKGROUND: Slit diaphragm is a specialized adhesion junction between the opposing podocytes, establishing the final filtration barrier to urinary protein loss. At the cytoplasmic insertion site of each slit diaphragm there is an electron-dense and protein-rich cellular compartment that is essential for slit diaphragm integrity and signal transduction. Mutations in genes that encode components of this membrane-less compartment have been associated with glomerular diseases. However, the molecular mechanism governing formation of compartmentalized slit diaphragm assembly remains elusive. METHODS: We systematically investigated the interactions between key components at slit diaphragm, such as MAGI2, Dendrin, and CD2AP, through a combination of biochemical, biophysical, and cell biologic approaches. RESULTS: We demonstrated that MAGI2, a unique MAGUK family scaffold protein at slit diaphragm, can autonomously undergo liquid-liquid phase separation. Multivalent interactions among the MAGI2-Dendrin-CD2AP complex drive the formation of the highly dense slit diaphragm condensates at physiologic conditions. The reconstituted slit diaphragm condensates can effectively recruit Nephrin. A nephrotic syndrome-associated mutation of MAGI2 interfered with formation of the slit diaphragm condensates, thus leading to impaired enrichment of Nephrin. CONCLUSIONS: Key components at slit diaphragm (e.g., MAGI2 and its complex) can spontaneously undergo phase separation. The reconstituted slit diaphragm condensates can be enriched in adhesion molecules and cytoskeletal adaptor proteins. Therefore, the electron-dense slit diaphragm assembly might form via phase separation of core components of the slit diaphragm in podocytes.

The Combination of Cell Cultured Technology and In Silico Model to Inform the Drug Development.

Human-derived in vitro models can provide high-throughput efficacy and toxicity data without a species gap in drug development. Challenges are still encountered regarding the full utilisation of massive data in clinical settings. The lack of translated methods hinders the reliable prediction of clinical outcomes. Therefore, in this study, in silico models were proposed to tackle these obstacles from in vitro to in vivo translation, and the current major cell culture methods were introduced, such as human-induced pluripotent stem cells (hiPSCs), 3D cells, organoids, and microphysiological systems (MPS). Furthermore, the role and applications of several in silico models were summarised, including the physiologically based pharmacokinetic model (PBPK), pharmacokinetic/pharmacodynamic model (PK/PD), quantitative systems pharmacology model (QSP), and virtual clinical trials. These credible translation cases will provide templates for subsequent in vitro to in vivo translation. We believe that synergising high-quality in vitro data with existing models can better guide drug development and clinical use.

Magnesium Isoglycyrrhizinate Reduces Hepatic Lipotoxicity through Regulating Metabolic Abnormalities.

The excessive accumulation of lipids in hepatocytes induces a type of cytotoxicity called hepatic lipotoxicity, which is a fundamental contributor to liver metabolic diseases (such as NAFLD). Magnesium isoglycyrrhizinate (MGIG), a magnesium salt of the stereoisomer of natural glycyrrhizic acid, is widely used as a safe and effective liver protectant. However, the mechanism by which MGIG protects against NAFLD remains unknown. Based on the significant correlation between NAFLD and the reprogramming of liver metabolism, we aimed to explore the beneficial effects of MGIG from a metabolic viewpoint in this paper. We treated HepaRG cells with palmitic acid (PA, a saturated fatty acid of C16:0) to induce lipotoxicity and then evaluated the antagonistic effect of MGIG on lipotoxicity by investigating the cell survival rate, DNA proliferation rate, organelle damage, and endoplasmic reticulum stress (ERS). Metabolomics, lipidomics, and isotope tracing were used to investigate changes in the metabolite profile, lipid profile, and lipid flux in HepaRG cells under different intervention conditions. The results showed that MGIG can indeed protect hepatocytes against PA-induced cytotoxicity and ERS. In response to the metabolic abnormality of lipotoxicity, MGIG curtailed the metabolic activation of lipids induced by PA. The content of total lipids and saturated lipids containing C16:0 chains increased significantly after PA stimulation and then decreased significantly or even returned to normal levels after MGIG intervention. Lipidomic data show that glycerides and glycerophospholipids were the two most affected lipids. For excessive lipid accumulation in hepatocytes, MGIG can downregulate the expression of the metabolic enzymes (GPATs and DAGTs) involved in triglyceride biosynthesis. In conclusion, MGIG has a positive regulatory effect on the metabolic disorders that occur in hepatocytes under lipotoxicity, and the main mechanisms of this effect are in lipid metabolism, including reducing the total lipid content, reducing lipid saturation, inhibiting glyceride and glycerophospholipid metabolism, and downregulating the expression of metabolic enzymes in lipid synthesis.

Effects of polystyrene microplastic on uptake and toxicity of copper and cadmium in hydroponic wheat seedlings (Triticum aestivum L.).

Microplastics are widespread in freshwater environments, their biological effects and combined effects of other pollutants have attracted extensive attention. In this study, we investigated the adsorption properties of heavy metals onto polystyrene (PS) microplastics as well as the bioavailability and toxicity of microplastics and heavy metals by hydroponic wheat seedlings experiment. Results showed that PS microplastics (0.5 µm, 100 mg/L) had no significant effect on wheat seedlings growth, photosynthesis, and reactive oxygen species (ROS) content. However, PS microplastics could adsorb copper and cadmium, with a predominantly chemisorption. The accumulation of copper and cadmium in wheat seedlings reduced in the presence of PS microplastics, which meant the toxic effect by heavy metals might be mitigated. Compared with single heavy metals treatments, the combination of PS microplastics and heavy metals increased chlorophyll content, enhanced photosynthesis and reduced the accumulation of ROS. These findings suggest that PS microplastics (0.5 µm, 100 mg/L) have a mitigating effect on the bioavailability and toxicity of copper and cadmium.

Phase separation-mediated condensation of Whirlin-Myo15-Eps8 stereocilia tip complex.

Stereocilia, the mechanosensory organelles on the apical surface of hair cells, are necessary to detect sound and carry out mechano-electrical transduction. An electron-dense matrix is located at the distal tips of stereocilia and plays crucial roles in the regulation of stereocilia morphology. Mutations of the components in this tip complex density (TCD) have been associated with profound deafness. However, the mechanism underlying the formation of the TCD is largely unknown. Here, we discover that the specific multivalent interactions among the Whirlin-myosin 15 (Myo15)-Eps8 complex lead to the formation of the TCD-like condensates through liquid-liquid phase separation. The reconstituted TCD-like condensates effectively promote actin bundling. A deafness-associated mutation of Myo15 interferes with the condensates formation and consequently impairs actin bundling. Therefore, our study not only suggests that the TCD in hair cell stereocilia may form via phase separation but it also provides important clues for the possible mechanism underlying hearing loss.