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Vibrio parahaemolyticus and microplastics are prevalent in the ocean. Bacteria attach onto plastic particles, forming harmful biofilms that collectively threaten bivalve health. This study investigates the interaction between polyamide microplastics (PA: particle size 38 ± 12 µm) and V. parahaemolyticus, as well as their combined impact on thick-shelled mussels (Mytilus coruscus). We introduced 10 11 CFU/L of V. parahaemolyticus into varying PA concentrations (0, 5, 50, and 500 particles/L) to observe growth over 14 h and biofilm formation after 48 h. Our findings indicate that microplastics suppress biofilm formation and virulence gene expression. Four treatments were established to monitor mussel responses: a control group without PA or V. parahaemolyticus; a group with 50 particles/L PA; a group with 10 11 CFU/L V. parahaemolyticus; and a co-exposure group with both 50 particles/L PA and 10 11 CFU/L V. parahaemolyticus, over a 14-day experiment. However, combined stress from microplastics and Vibrio led to immune dysregulation in mussels, resulting in intestinal damage and microbiome disruption. Notably, V. parahaemolyticus had a more severe impact on mussels than microplastics alone, yet their coexistence reduced some harmful effects. This study is the first to explore the interaction between microplastics and V. parahaemolyticus, providing important insights for ecological risk assessments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Aims: Artificial reefs play a vital role in restoring and creating new habitats for marine species by providing suitable substrates, especially in areas where natural substrates have been degraded or lost due to declining water quality, destructive fishing practices, and coral diseases. Artificial reef restoration aimed at coral larval settlement is gaining prominence and initially depends on the development of biofilms on reef surfaces. In this study, we hypothesized that different artificial reef materials selectively influence the composition of biofilm bacterial communities, which in turn affected coral larval settlement and the overall success of coral rehabilitation efforts. To test this hypothesis, we evaluated the impact of six different reef-made materials (porcelain, granite, coral skeleton, calcium carbonate, shell cement, and cement) on the development of biofilm bacterial communities and their potential to support coral larval settlement., Methods and Results: The biofilm bacterial communities were developed on different artificial reef materials and studied using 16S rRNA gene amplicon sequencing and analysis. The bacterial species richness and evenness were significantly (P < 0.05) low in the seawater, while these values were high in the reef materials. At the phylum level, the biofilm bacterial composition of all materials and seawater was majorly composed of Pseudomonadota, Cyanobacteria, and Bacteroidetes; however, significantly (P < 0.05) low Bacteroidetes were found in the seawater. At the genus level, Thalassomonas, Glaciecola, Halomicronema, Lewinella, Hyphomonas, Thalassospira, Polaribacter, and Tenacibaculum were significantly (P < 0.05) low in the coral skeleton and seawater, compared to the other reef materials. The genera Pseudoaltermonas and Thalassomonas (considered potential inducers of coral larval settlement) were highly abundant in the shell-cement biofilm, while low values were found in the biofilm of the other materials., Conclusion: The biofilm bacterial community composition can be selective for different substrate materials, such as shell cement exhibited higher abundances of bacteria known to facilitate coral larval settlement, highlighting their potential in enhancing restoration outcomes., (© The Author(s) 2024. Published by Oxford University Press on behalf of Applied Microbiology International.)

Fucoidan is a sulfate-containing polysaccharide derived from the cell walls of brown algae and marine invertebrates. Fucoidan is widely used for the treatment of various diseases owing to its various biological activities. Dermatitis is an inflammatory reaction that affects the skin. The primary clinical manifestations include atopic dermatitis (AD or eczema) and various subtypes of contact dermatitis. The treatment of dermatitis primarily improves symptoms and reduces inflammation. However, owing to individual variations, some patients have a poor prognosis or symptom recurrence after conventional treatment. Owing to the excellent anti-allergic and anti-inflammatory activities of the low cost nature compound fucoidan, its therapeutic effect in inflammatory diseases has recently attracted the attention of researchers. This article summarizes and analyzes the advantages and pharmacological mechanisms of fucoidan against dermatitis to provide a reference for the selection of drugs for the treatment of dermatitis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Tire wear particles (TWPs) released during vehicle driving can enter water bodies, leading to leaching of tire additives (TAs) in aquatic environments. However, the transformation behavior and related ecological impacts of TAs and their transformation products (TPs) remain unclear. In this study, laboratory-based simulation experiments and field investigations were conducted to explore the transformation mechanisms and ecological risks of TAs. After being placed in river water for 24 h, about 7-95% of 12 investigated TAs in TWPs were leached. Forty-eight TPs from eight TAs were tentatively identified along with different transformation pathways via suspect screening by high-resolution mass spectrometry. Semiquantitative results indicated that TPs derived from N -(1,3-dimethylbutyl)- N '-phenyl- p -phenylene-diamine (6PPD) were predominant in leachates, while aryl hydrolysis and quinone pathways were the main transformation pathways. Field investigations on urban surface water samples from 16 sites in Hong Kong revealed the occurrence of 17 TAs and 1 TP, with concentrations ranging from 13.9 to 2230 ng/L (median ± standard deviation: 226 ± 534 ng/L). Sixteen TPs from six TAs were additionally identified via suspect screening. It is estimated that 6PPD-quinone and seven TAs could pose medium to high ecological risk, while N -(1,3-dimethylbutyl)- N '-phenyl- p -quinonediimine, a frequently detected TP, was identified as a persistent-bioaccumulative-toxic substance.

Background: Nephroureterectomy with bladder cuff excision is the standard treatment for high-risk upper urinary tract urothelial carcinoma (UTUC). The role of minimally invasive surgery in treating locally advanced UTUC remains controversial. This study aimed to compare the outcomes of open, laparoscopic, and robotic surgeries for managing locally advanced UTUC., Methods: We retrospectively reviewed 705 patients with locally advanced UTUC from multiple institutions throughout Taiwan. Perioperative outcomes and oncological outcomes, such as cancer-specific survival, overall survival, disease-free survival and bladder-free survival, were compared between the open, laparoscopic and robotic groups., Results: The minimally invasive group had better overall and cancer-specific survival (CSS) rates. The 2-year CSS rates of the open, laparoscopic and robotic groups were 71%, 83%, and 77% respectively (p < 0.001). The robotic group had similar outcomes to the laparoscopic group. (p = 0.061, 0.825, 0.341 for OS, CSS, DFS respectively.) More lymph node dissections were performed and more lymph nodes were harvested in the robotic group (p = 0.009)., Conclusions: Our results demonstrated that minimally invasive surgery, including laparoscopic and robotic surgery, for locally advanced UTUC resulted in oncological outcomes that are non-inferior to those of open surgery., (© 2024. The Author(s).)

Sub-10 µm microplastics (MPs) in aquatic environments pose significant ecological and health risks due to their mobility and potential to carry harmful microcontaminants. Our effluent analysis from a Hong Kong Sewage Treatment Works shows that traditional treatment often fails to effectively remove these MPs. These small-sized MPs are commonly neglected due to challenges in accurate quantification, analysis, and removal. This study introduces a nanobubble-assisted flotation process that enhances the removal efficiency of both regular and irregular small-sized MPs from wastewater. The proposed process outperforms the traditional flotation process by fostering a more effective interaction between bubbles and MPs, increasing removal rates of MPs from 1 µm to 10 µm by up to 12% and providing a total efficiency boost of up to 17% for various particle sizes. Improvements are attributed to enhanced collision and adhesion probabilities, hydrophobic interactions, as well as better floc flotation. Supported by empirical evidence, mathematical models, and Molecular Dynamics simulations, this research elucidates the nanoscale mechanisms at play. The findings confirm the nanobubble-assisted flotation technique as an innovative and practical approach to removing sub-10 µm MPs in water treatment processes., (© 2024. The Author(s).)

Bone metastasis is the primary cause of death among patients with advanced prostate cancer (PCa). PCa tends to spread to bones and acquire the bone-like phenotype, causing osteoblastic bone metastasis. Unfortunately, there is no effective treatment for this condition. However, melatonin, which regulates our circadian rhythm, has been found to have anti-tumor properties. It has yet to be established whether it is effective in treating osteoblastic PCa metastasis. Our findings show that melatonin inhibits the production of endothelin-1 (ET-1) in osteoblastic PCa cells, suppressing osteoblast differentiation. Clinical results indicate that bone metastatic PCa patients have higher levels of ET-1 compared to nonmetastatic PCa patients. Furthermore, melatonin-induced miR-let-7f-5p inhibits ET-1-promoted osteoblast differentiation in osteoblastic PCa. Melatonin also suppresses the property of osteomimicry in osteoblastic PCa cells. Importantly, in the intratibia injection PCa metastasis model, melatonin decreased osteoblastic PCa tumor growth, inhibiting ET-1 production and osteoblast differentiation in vivo. Taken together, melatonin inhibits osteoblastic PCa-regulated osteoblastogenesis by reducing ET-1 production through upregulation of miR-let-7f-5p, while suppressing the property of osteomimicry in osteoblastic PCa. Melatonin therapy could be a promising approach to treating bone metastasis in osteoblastic PCa., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Microplastics (MPs) deposited on urban roads are often flushed into water bodies via drainage systems without treatment, and MP concentrations in the initial road runoff may be particularly high. Yet, there is only a limited understanding of the characteristics, dynamics, and impacts of MPs in urban road runoff. In this study, stormwater and rainwater samples were collected from seven different locations in Hong Kong across 11 rainfall events between February 2021 and September 2022. Characteristics of MPs in the collected samples were analyzed in detail, along with the dynamics of MP concentration in rainfall events, possible influencing factors, and ecological risks. The results show that MP concentration in the initial road runoff is particularly high during a rainfall episode. Overall, the median MP abundance in the collected runoff samples (185 particles/L) was 4.6 times higher than that in rainwater (40 particles/L). The most common polymers identified were polyethylene, polypropylene, and polystyrene, with fragments being the dominant shape. Over 60 % of MP sizes were smaller than 300 μm in the runoff samples. Additionally, risk assessments based on the Polymer Risk Index (PRI) classified most road sites in pollution classes II to III (PRI = 13.3-138.0), indicating moderate to high ecological risks. It appears that MP abundance in the initial runoff was significantly influenced by seasonal changes. These findings highlight urban roads as a major source of MP pollution in stormwater runoff and emphasize the importance of addressing the initial runoff in pollution control., Competing Interests: Declaration of competing interest Authors declare that they have no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microplastics (MPs) are pervasive environmental contaminants that have infiltrated even the most remote ecosystems. Despite their widespread distribution, the transfer patterns and impacts of MPs in remote lakes remain poorly understood. This study aimed to address the knowledge gap regarding the pathways and consequences of MP pollution in these isolated environments. Focusing on Kyêbxang Co, a remote salt lake in Tibet, this study investigated the transfer patterns, sources and ecological impacts of MPs, providing insights into their mobility and fate in pristine ecosystems. Water, sediment and biota (brine shrimp) samples from Kyêbxang Co, collected during the summer of 2020, were analyzed using µ-Raman spectroscopy to determine MP abundances, polymer types and potential sources. Findings indicated significant MP contamination in all examined media, with concentrations highlighting the role of runoff in transporting MPs to remote locations. The majority of detected MPs were small fragments (<0.5 mm), constituting over 93 %, with polypropylene being the predominant polymer type. The presence of a halocline may slow the descent of MPs, potentially increasing the exposure and ingestion risk to brine shrimp. Despite the currently low ecological risk estimated for MPs, this study underscores the need for long-term monitoring and development of a comprehensive ecological risk assessment model for MPs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Pollutants often exist as mixtures in environmental settings, creating a challenge in selecting the most effective combination of biomarkers for routine monitoring. This study was conducted seasonally in Victoria Harbour, Hong Kong, to compare the responses of nine biomarkers in the green-lipped mussel Perna viridis with respect to its tissue levels of persistent organic pollutants and heavy metals. Multivariate statistical techniques were utilised to determine the single best predictor and optimal subset of biomarkers in P. viridis for each of the four scenarios: representing overall biomarker responses in the dry season, and wet season, as well as correlating tissue levels of mixed pollutants in the dry season, and wet season. Our findings recommend lysosomal destabilisation, and the nucleic acid ratio of RNA to DNA, as the core biomarkers in P. viridis for marine pollution monitoring. The non-specificity of these biomarkers allows effective identification of pollution hotspots and guides further detailed assessment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Due to continuous increase in marine plastic waste, microplastics are ubiquitous in the marine environment. However, there are few studies on the harmful effects caused by microplastics with different particle sizes, and the interaction between particle size and concentration requires further investigation. This study explored the differences in physiological and biochemical responses, photosynthesis and oxidative stress damage of the microalga Isochrysis galbana exposed to three different particle size microplastics. It was found that different particle sizes and concentrations of microplastics resulted in significant differences (p < 0.05) in the growth rate, photosynthesis, and oxidative stress level of I. galbana. With the decrease of the particle size and lowering concentration of microplastics, the growth rate, photosynthesis and oxidative stress levels of I. galbana were reduced. Significant differences in photosynthesis and oxidative stress levels were observed when I. galbana was exposed to smallest particle size and lowest concentration of microplastics. This study provides new insights about whether polystyrene microplastics of different particle sizes and concentrations exhibit complex effects on microalgae, and explores the underlying reasons for such effects. In short, this study predicts the exacerbating adverse effects of microplastic pollution on the primary productivity, with significant implications for marine food webs and ecosystem health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Introduction: Growing concerns regarding the reproductive toxicity associated with daily life exposure to micro-/nano-plastics (abbreviated as MNPs) have become increasingly prevalent. In reality, MNPs exposure involves a heterogeneous mixture of MNPs of different sizes rather than a single size., Methods: In this study, an oral exposure mouse model was used to evaluate the effects of MNPs of four size ranges: 25-30 nm, 1-5 µm, 20-27 µm, and 125-150 µm. Adult male C57BL/6 J mice were administered environmentally relevant concentrations of 0.1 mg MNPs/day for 21 days. After that, open field test and computer assisted sperm assessment (CASA) were conducted. Immunohistochemical analyses of organ and cell type localization of MNPs were evaluated. Testicular transcriptome analysis was carried out to understand the molecular mechanisms., Results: Our result showed that MNPs of different size ranges all impaired sperm motility, with a decrease in progressive sperm motility, linearity and straight-line velocity of sperm movement. Alterations did not manifest in animal locomotion, body weight, or sperm count. Noteworthy effects were most pronounced in the smaller MNPs size ranges (25-30 nm and 1-5 µm). Linear regression analysis substantiated a negative correlation between the size of MNPs and sperm curvilinear activity. Immunohistochemical analysis unveiled the intrusions of 1-5 µm MNPs, but not 20-27 µm and 125-150 µm MNPs, into Leydig cells and testicular macrophages. Further testicular transcriptomic analysis revealed perturbations in pathways related to spermatogenesis, oxidative stress, and inflammation. Particularly within the 1-5 µm MNPs group, a heightened perturbation in pathways linked to spermatogenesis and oxidative stress was observed., Conclusions: Our data support the size-dependent impairment of MNPs on sperm functionality, underscoring the pressing need for apprehensions about and interventions against the escalation of environmental micro-/nano-plastics contamination. This urgency is especially pertinent to small-sized MNPs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The COVID-19 pandemic has resulted in unprecedented plastic pollution from single-used personal protective equipment (PPE), especially face masks, in coastal and marine environments. The secondary pollutants, microplastics from face masks (mask MP), rise concern about their detrimental effects on marine organisms, terrestrial organisms and even human. Using a mouse model, oral exposure to mask MP at two doses, 0.1 and 1 mg MP/day for 21 days, caused no change in animal locomotion, total weight, or sperm counts, but caused damage to sperm motility with increased curvilinear velocity (VCL). The high-dose mask MP exposure caused a significant decrease in linearity (LIN) of sperm motility. Further testicular transcriptomic analysis revealed perturbed pathways related to spermatogenesis, oxidative stress, inflammation, metabolism and energy production. Collectively, our findings substantiate that microplastics from face masks yield adverse effects on mammalian reproductive capacity, highlighting the need for improved plastic waste management and development of environmentally friendly materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Rayon microfibers, micro-sized semi-synthetic polymers derived from cellulose, have been frequently detected and reported as "micropollutants" in marine environments. However, there has been limited research on their ecotoxicity and combined effects with persistent organic pollutants (POPs). To address these knowledge gaps, thick-shell mussels (Mytilus coruscus) were exposed to rayon microfibers at 1000 pieces/L, along with polychlorinated biphenyls (PCBs) at 100 and 1000 ng/L for 14 days, followed by a 7-day recovery period. We found that rayon microfibers at the environmentally relevant concentration exacerbated the irreversible effects of PCBs on the immune and digestive systems of mussels, indicating chronic and sublethal impacts. Furthermore, the results of 16 s rRNA sequencing demonstrated significant effects on the community structure, species richness, and diversity of the mussels' intestinal microbiota. The branching map analysis identified the responsive bacteria to rayon microfibers and PCBs belonging to the Proteobacteria, Actinobacteriota, and Bacteroidota phyla. Despite not being considered a conventional plastic, the extensive and increasing use of rayon fibers, their direct toxicological effects, and their interaction with POPs highlight the need for urgent attention, investigation, and regulation to address their contribution to "micropollution"., Competing Interests: Declaration of Competing Interest The authors state that they have no known competing financial interests or personal relationships that could affect the work reported in this article., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Marine hypoxia poses a significant challenge in the contemporary marine environment. The horseshoe crab, an ancient benthic marine organism, is confronted with the potential threat of species extinction due to hypoxia, making it an ideal candidate for studying hypoxia tolerance mechanisms. In this experiment, juvenile Tachypleus tridentatus were subjected to a 21-day trial at DO:2 mg/L (hypoxia) and DO:6 mg/L conditions. The experimental timeline included a 14-day exposure phase followed by a 7-day recovery period. Sampling occurred on days 0, 7, 14, and 21, where the period from day 14 to day 21 corresponds to seven days of recuperation. Several enzymatic activities of important proteins throughout this investigation were evaluated, such as succinate dehydrogenase (SDH), phosphofructokinase (PFK), hexokinase (HK), lactate dehydrogenase (LDH), and pyruvate kinase (PK). Concurrently, the relative expression of hexokinase-1 (HK), hypoxia-inducible factor 1-alpha inhibitor (FIH), and hypoxia-inducible factor 1-alpha (HIF-1α), pyruvate dehydrogenase phosphatase (PDH), succinate dehydrogenase assembly factor 4 (SDH), and Glucose-6-phosphatase (G6Pase) were also investigated. These analyses aimed to elucidate alterations in the hypoxia signaling pathway and respiratory energy metabolism. It is revealed that juvenile T. tridentatus initiated the HIF pathway under hypoxic conditions, resulting in an upregulation of HIF-1α and FIH-1 gene expression, which in turn, influenced a shift in metabolic patterns. Particularly, the activity of glycolysis-related enzymes was promoted significantly, including PK, HK, PKF, LDH, and the related HK gene. In contrast, enzymes linked to aerobic respiration, PDH, and SDH, as well as the related PDH and SDH genes, displayed down-regulation, signifying a transition from aerobic to anaerobic metabolism. Additionally, the activity of gluconeogenesis-related enzymes such as PK and G6Pase gene expression were significantly elevated, indicating the activation of gluconeogenesis and glycogenolysis pathways. Consequently, juvenile T. tridentatus demonstrated an adaptive response to hypoxic conditions, marked by changes in respiratory energy metabolism modes and the activation of hypoxia signaling pathways., Competing Interests: Declaration of competing interest The authors state that they have no known competing financial interests or personal relationships that could affect the work reported in this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The green-lipped mussel Perna viridis was utilised for pollution biomonitoring in Victoria Harbour and its adjacent aquaculture area in Hong Kong. P. viridis was collected from a reference site and redeployed at five study sites for five weeks during the dry and wet seasons of 2019. Our study found various polycyclic aromatic hydrocarbons (PAHs) and heavy metals in the mussel tissue, while polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were not detected. P. viridis at the reference site generally displayed lower levels of pollutants. Comparing with previous research in the 1980s and 2000s, we observed substantial reduction in the tissue levels of PAHs, PCBs, OCPs and heavy metals in P. viridis. The human health risks associated with consuming these mussels were determined to be insignificant. Our findings imply that the Harbour Area Treatment Scheme has been effective in improving the water quality in Victoria Harbour and its adjacent aquaculture area., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

The investigation of pharmaceuticals as emerging contaminants in marine biota has been insufficient. In this study, we examined the presence of 51 pharmaceuticals in edible oysters along the coasts of the East and South China Seas. Only nine pharmaceuticals were detected. The mean concentrations of all measured pharmaceuticals in oysters per site ranged from 0.804 to 15.1 ng g -1 of dry weight, with antihistamines being the most common. Brompheniramine and promethazine were identified in biota samples for the first time. Although no significant health risks to humans were identified through consumption of oysters, 100-1000 times higher health risks were observed for wildlife like water birds, seasnails, and starfishes. Specifically, sea snails that primarily feed on oysters were found to be at risk of exposure to ciprofloxacin, brompheniramine, and promethazine. These high risks could be attributed to the monotonous diet habits and relatively limited food sources of these organisms. Furthermore, taking chirality into consideration, chlorpheniramine in the oysters was enriched by the S -enantiomer, with a relative potency 1.1-1.3 times higher when chlorpheniramine was considered as a racemate. Overall, this study highlights the prevalence of antihistamines in seafood and underscores the importance of studying enantioselectivities of pharmaceuticals in health risk assessments.

Microplastic pollution, an emerging pollution issue, has become a significant environmental concern globally due to its ubiquitous, persistent, complex, toxic, and ever-increasing nature. As a multifaceted and diverse suite of small plastic particles with different physicochemical properties and associated matters such as absorbed chemicals and microbes, future research on microplastics will need to comprehensively consider their multidimensional attributes. Here, we introduce a novel, conceptual framework of the "microplastome", defined as the entirety of various plastic particles (<5 mm), and their associated matters such as chemicals and microbes, found within a sample and its overall environmental and toxicological impacts. As a novel concept, this paper aims to emphasize and call for a collective quantification and characterization of microplastics and for a more holistic understanding regarding the differences, connections, and effects of microplastics in different biotic and abiotic ecosystem compartments. Deriving from this lens, we present our insights and prospective trajectories for characterization, risk assessment, and source apportionment of microplastics. We hope this new paradigm can guide and propel microplastic research toward a more holistic era and contribute to an informed strategy for combating this globally important environmental pollution issue.

The innate immunity of marine bivalves is challenged upon exposure to heat stress, especially with increases in the frequency and intensity of heat waves. TLR4 serves a classical pattern recognition receptor in recognizing pathogenic microorganisms and activating immune responses. In this study, three genes, HMTLR4 , HMMyD88 and HMTRAF6 , were characterized as homologs of genes in the TLR4-MyD88 signaling pathway in the selected scallop strain "Hongmo No. 1". According to RT-PCR, acute heat stress (32 °C) inhibited genes in the TLR4-MyD88 signaling pathway, and LPS stimulation-induced activation of TLR4-MyD88 signal transduction was also negatively affected at 32 °C. ELISA showed LPS-induced tumor necrosis factor alpha (TNF-α) or lysozyme (LZM) activity, but this was independent of temperature. RNA interference (RNAi) confirmed that HMTLR4 silencing suppressed the expression of its downstream gene, whether at 24 °C or at 32 °C. The level of TNF-α and the activity of LZM also decreased after injection with dsRNA, indicating a negative effect on the innate immunity of scallops. Additionally, acute heat stress affected the suppression of downstream gene expression when compared with that at 24 °C, which led us to the hypothesis that heat stress directly influences the downstream targets of HMTLR4 . These results enrich the knowledge of scallop immunity under heat stress and can be beneficial for the genetic improvement of new scallop strains with higher thermotolerance.

Microplastic (MP) pollution has emerged as a global environmental concern due to its ubiquity and harmful impacts on ecosystems and human health. MP assessment has therefore become increasingly necessary and common in environmental and experimental samples. Microscopy and spectroscopy are widely employed for the physical and chemical characterization of MPs. However, these analytical methods often require time-consuming pretreatments of samples or expensive instrumentation. In this work, we develop a portable and cost-effective polarization holographic imaging system that prominently incorporates deep learning techniques, enabling efficient, high-throughput detection and dynamic analysis of MPs in aqueous environments. The integration enhances the identification and classification of MPs, eliminating the need for extensive sample preparation. The system simultaneously captures holographic interference patterns and polarization states, allowing for multimodal information acquisition to facilitate rapid MP detection. The characteristics of light waves are registered, and birefringence features are leveraged to classify the material composition and structures of MPs. Furthermore, the system automates real-time counting and morphological measurements of various materials, including MP sheets and additional natural substances. This innovative approach significantly improves the dynamic monitoring of MPs and provides valuable information for their effective filtration and management., (© 2024. The Author(s).)

Purpose: The purpose of this study is to evaluate the rates of pathological complete response (ypT0N0/X) and pathological response (ypT1N0/X or less) in patients with upper tract urothelial cancer who were treated with neo-adjuvant chemotherapy and to examine their impact on oncological outcomes., Methods: This study is a multi-institutional retrospective analysis of patients with high-risk upper tract urothelial cancer who underwent neoadjuvant chemotherapy and radical nephroureterectomy between 2002 and 2021. Logistic regression analyses were used to investigate all clinical parameters for response after neoadjuvant chemotherapy. Cox proportional hazard models were performed to assess the effect of the response on the oncological outcomes., Results: A total of 84 patients with UTUC who received neo-adjuvant chemotherapy were identified. Among them, 44 (52.4%) patients received cisplatin-based chemotherapy, and 22 (26.2%) patients had a carboplatin-based regimen. The pathological complete response rate was 11.6% (n = 10), and the pathological response rate was 42.9% (n = 36). Multifocal tumors or tumors larger than 3 cm significantly reduced the odds of pathological response. In the multivariable Cox proportional hazard model, pathological response was independently associated with better overall survival (HR 0.38, p = 0.024), cancer-specific survival (HR 0.24, p = 0.033), and recurrence-free survival (HR 0.17, p = 0.001), but it was not associated with bladder recurrence-free survival (HR 0.84, p = 0.69)., Conclusion: Pathological response after neo-adjuvant chemotherapy and radical nephroureterectomy is strongly associated with patient survival and recurrence, and it might be a good surrogate for evaluating the efficacy of neo-adjuvant chemotherapy in the future., Competing Interests: Conflicts of interest The authors have no conflicts of interest relevant to this article., (Copyright © 2023 Formosan Medical Association. Published by Elsevier B.V. All rights reserved.)

Nanoplastics (NPs) and heavy metals are typical marine pollutants, affecting the gut microbiota composition and molting rate of marine organisms. Currently, there is a lack of research on the toxicological effects of combined exposure to horseshoe crabs. In this study, we investigated the effects of NPs and copper on the expression of molt-related genes and gut microbiome in juvenile tri-spine horseshoe crabs Tachypleus tridentatus by exposing them to NPs (100 nm, 10 4 particles L -1 ) and/or Cu 2+ (10 μgL -1 ) in seawater for 21 days. Compared with the control group, the relative mRNA expression of ecdysone receptor (EcR), retinoid x receptor (RXR), calmodulin-A-like isoform X1 (CaM X1), and heat shock 70 kDa protein (Hsp70) were significantly increased under the combined stress of NPs and Cu 2+ . There were no significant differences in the diversity and abundance indices of the gut microbial population of horseshoe crabs between the NPs and/or Cu 2+ groups and the control group. According to linear discriminant analysis, Oleobacillus was the most abundant microorganism in the NPs and Cu 2+ stress groups. These results indicate that exposure to either NPs stress alone or combined NPs and Cu 2+ stress can promote the expression levels of juvenile molting genes. NPs exposure has a greater impact on the gut microbial community structure of juvenile horseshoe crabs compared to Cu 2+ exposure. This study is helpful for predicting the growth and development of horseshoe crabs under complex environmental pollution., Competing Interests: Declaration of competing interest The authors state that they have no known competing financial interests or personal relationships that could affect the work reported in this article., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Nano‑titanium dioxide (nTiO 2 ) is a widely used nanomaterial posing potential ecological risk for marine ecosystems that might be enhanced by elevated temperatures such as expected during climate change. nTiO 2 may affect benthic filter feeders like mussels through waterborne exposures and via food chain due to the adsorption on/in algae. Mussel byssus are proteinaceous fibers secreted by byssal glands of the mussels for attachment. Byssus production and mechanical properties are sensitive to environmental stressors but the combined effects of warming and nTiO 2 on byssus performance of mussels are unclear hampering our understanding of the predation and dislodgement risk of mussels under the multiple stressor scenarios. We explored the effects of a short-term (14-day) single and combined exposures to warming (28 °C) and 100 μg L -1 nTiO 2 (including food co-exposure) on the byssus performance of the thick shell mussel Mytilus coruscus. The mechanical strength (measured as the breaking force) of the byssal threads was impaired by warming and nTiO 2 (including food co-exposure), but the number and length of the byssal threads were increased. The mRNA expression levels of mussel foot proteins (mfp-3, mfp-5) and pre-collagens (preCOL-D, preCOL-P, preCOL-NG) were up-regulated to varying degrees, with the strongest effects induced by warming. This indicates that the physiological and molecular mechanisms of byssus secretion are plastic. However, downregulation of the mRNA expression of preCOL-D and preCOL-P under the combined warming and nTiO 2 exposures indicate the limits of these plasticity mechanisms and suggest that the attachment ability and survival of the mussels may be impaired if the pollution or temperature conditions further deteriorate., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Given the potential risk to the ecosystem, attention has increased in recent decades to the contamination of the aquatic environment by microplastics (MPs). Due to the limitations of conventional analysis methods of MPs, little is known about the size distribution and abundance of a full-size MPs from 1 μm to 5 mm. The present study quantified MPs with size ranges of 50 μm - 5 mm and 1-50 μm in the coastal marine waters from twelve locations in Hong Kong using fluorescence microscopy and flow cytometry respectively, during the end of wet (September 2021) and dry (March 2022) seasons. The average abundance of MPs with size ranges of 50 μm - 5 mm and 1-50 μm from twelve sampling locations marine surface waters were found ranging from 27 to 104 particles L -1 and 43,675-387,901 particles L -1 in the wet season respectively, and 13-36 particles L -1 and 23,178-338,604 particles L -1 in the dry season respectively. Significant temporal and spatial variations of small MPs abundance might be observed at the sampling locations, which were contributed by the influences of the estuary of Pearl River, sewage discharge points, land structure, and other anthropogenic activities. Based on the MPs abundance information, ecological risk assessment was conducted and revealed that the small MPs (< 10 μm) in coastal marine surface waters may pose potential health risks to aquatic organisms. Additional risk assessments are needed in order to determine whether or not the MPs exposure would cause health risks to the public., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Nanoplastics (NPs) are increasingly recognized as a newly emerging pollutant in the environment. NPs can enable the colonization of microbial pathogens on their surfaces and adsorb toxic pollutants, such as heavy metals and residual antibiotics. Although the dissemination of plastic particles in water bodies and the atmosphere is widely studied, the dissemination of NPs and adsorbed pollutants on land, via biological means, is poorly understood. Since soil animals, such as the bacterivorous nematode Caenorhabditis elegans ( C. elegans ), are highly mobile, this raises the possibility that they play an active role in disseminating NPs and adsorbed pollutants. Here, we established that antibiotic-resistant bacteria could aggregate with antibiotic-adsorbed NPs to form antibiotic-adsorbed NP-antibiotic resistant bacteria (ANP-ARB) aggregates, using polymyxins (colistin) as a proof-of-concept. Colistin-resistant mcr-1 bearing Escherichia coli from a mixed population of resistant and sensitive bacteria selectively aggregate with colistin-ANPs. In the soil microcosm, C. elegans fed on ANP-ARB clusters, resulting in the rapid spread of ANP-ARB by the nematodes across the soil at a rate of 40-60 cm per day. Our work revealed insights into how NPs could still disseminate across the soil faster than previously thought by "hitching a ride" in soil animals and acting as agents of antibiotic-resistant pathogens and antibiotic contaminants. This poses direct risks to ecology, agricultural sustainability, and human health.

The impacts of high-density microplastics, namely polyamine 6,6 (nylon), polymethyl methacrylate (PMMA) and polyethylene terephthalate (PET), on growth and behaviour of the endangered tri-spine horseshoe crab Tachypleus tridentatus were investigated for 100 days. Negative changes in wet weight and prosomal width of the juveniles were observed in all treatments of microplastics, but significant difference was only detected in prosomal width between control and PMMA. T. tridentatus became significantly less active upon exposure to nylon and PET. The extent of burrowing by T. tridentatus did not significantly differ among the treatments but was overall significantly reduced towards day 100. T. tridentatus exposed to PET significantly showed the lowest survival probability (30 %), compared to the other treatments (70-90 %). In conclusion, high-density microplastics compromised growth and behaviour of juvenile horseshoe crabs. Among the polymers that were tested, PET was considered more harmful and associated with higher mortality., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Microplastics represent an emerging environmental problem worldwide, raising ecological and food safety concerns. Compared to microplastics, there is growing evidence of an even higher abundance of submicro- and nanoplastics in the environment, but a reliable monitoring method for detecting these smaller-sized plastics is lacking. Herein we presented the application of surface-enhanced Raman scattering (SERS) for this purpose. Particles of polystyrene (PS; 600 nm) were used as the probe analyte. Gold nanourchins (AuNU; 50 nm), i.e. urchin-shaped nanoparticles with irregular spikes around the core, were used as the SERS-active substrate. The effectiveness of SERS on PS was evaluated at a single-particle level with different numbers of AuNU in order to determine the minimum conditions required for the onset of the SERS effect. Our findings suggest that SERS of a single particle of PS can be induced by as few as 1-5 particles of AuNU, and that the use of excitation wavelength at 785 nm is appropriate to meet the red-shifted surface plasmon resonance of AuNU upon aggregation. These specifications provide additional information for the development of SERS-based tools for detecting plastic particles < 1 µm in food and environmental samples., (Copyright © 2021. Published by Elsevier B.V.)

We report the results of experiments designed to evaluate the performance of a bubble barrier device for microplastics collection in natural and artificial streams. Bubble barrier is an innovative device based on the principle that pumping air to produce a vertical curtain of small air bubbles along the depth of a waterway creates a sufficient current to direct floating and non-floating particle towards a catchment device. The bubble barrier has been designed and already tested in rivers. Despite its use, there is a lack of information on the fluid mechanical functioning and performance, i.e., its ability to catch the largest number of microplastic particles. The aim of the present study is to test different bubble barriers configurations (length of the bubble generator, alignment with the main current) in different hydraulic conditions. We used a laboratory channel to produce a scaled river flow and we performed velocity measurements, and particle tracking visualization to understand how the bubble curtain could influence the water flow. The catchment performance of the different barriers has been tested using two types of particles, lighter and heavier than water. The results show that the system performance is strongly linked to a combination of the bubble generator configuration and the main properties of the flow. This study is the first attempt to provide scientific data on the bubble barrier and future design strategies depending on its application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The health concerns of microplastics (MPs) and nanoplastics (NPs) surge, but the key indicators to evaluate the adverse risks of MPs/NPs are elusive. Recently, MPs/Ps were found to disturb glucose and lipid metabolism in rodents, suggesting that MPs/NPs may play a role in obesity progression. In this study, we firstly demonstrated that the distribution of fluorescent polystyrene nanoplastics (nPS, 60 nm) white adipose tissue (WAT) of mice. Furthermore, nPS could traffic across adipocytes in vitro and reduced lipolysis under β-adrenergic stimulation in adipocytes in vitro and ex vivo. Consistently, chronic oral exposure to nPS at the dietary exposure relevant concentrations (3 and 223 μg/kg body weight) impaired fasting-induced lipid mobilization in obese mice and subsequently contributed to larger adipocyte size in the subcutaneous WAT. In addition, the chronic exposure of nPS induced macrophage infiltration in the small intestine and increased lipid accumulation in the liver, accelerating the disruption of systemic metabolism. Collectively, our findings highlight the potential obesogenic role of nPS via diminishing lipid mobilization in WAT of obese mice and suggest that lipolysis relevant parameters may be used for evaluating the adverse effect of MPs/NPs in clinics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Microbial biofilms are difficult to tackle in many infectious diseases. Candida albicans and Staphylococcus aureus are prevalent symbiotic strains in polymicrobial biofilms, which showed enhanced antimicrobial resistance and made identifying effective treatment techniques more difficult. The antibiofilm abilities of tachplesin I analogue peptide (TP11A) and tachplesin I were investigated quantitatively in this study. Both inhibited C. albicans monomicrobial, S. aureus monomicrobial, and C. albicans - S. aureus polymicrobial biofilms quite well. TP11A suppressed the biofilm- and virulence-related genes of C. albicans ( hwp 1 ) and S. aureus ( ica A , fnb B , agr A , hla , nor A , and sig B ) in the mixed biofilm, according to quantitative reverse transcription polymerase chain reaction analysis. We created an injectable thermosensitive in situ PLEL@TP11A gel system by simply adding TP11A into poly(d,l-lactide)-poly(ethylene glycol)-poly(d,l-lactide) (PLEL). Using C. albicans - S. aureus mixed infected wound models of mice, the in vivo therapeutic effect of TP11A and PLEL@TP11A in polymicrobial infections was investigated. The findings revealed that TP11A and PLEL@TP11A could efficiently reduce bacterial and fungal burden in wound infections, as well as accelerated wound healing. Based on above findings, TP11A might be an effective antimicrobial against C. albicans - S. aureus poly-biofilm formation and mixed infection.

To assess the efficacy and safety of robot-assisted anatrophic nephrolithotomy (RANL) as a choice of minimally invasive treatment for patients with complete staghorn stone. In a single-tertiary referral center retrospective study, 10 consecutive patients underwent RANL for complete staghorn stone. After dissection to the renal hilum and clamping of the renal vessels, an incision was made along the Brodel line and exposed the collecting system to extract the stone. Then, the collecting system and parenchyma were closed in layers. The outcomes included reduction of the stone burden, short- and long-term postoperative kidney function, and pain score. The average age of patients was 54.6 years and body mass index was 27.58 kg/m2. Mean warm ischemia time was 28.40 minutes, mean robotic console time was 137 minutes, and mean estimated blood loss was 83 mL. The mean length of stay was 5.4 days and there were no severe perioperative complications. Eight of 10 patients had >90% reduction in stone burden and 5 (50%) patients were completely stone-free. There was no significant decrease in postoperative estimated glomerular filtration rate compared with preoperative values after 1 month and 1 year. Our experience with RANL demonstrated efficacy and safety in the minimally invasive treatment of complete staghorn stone in short- and long-term follow-up periods., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

Microplastics are recognised as a ubiquitous and hazardous pollutant worldwide. These small-sized particles have been detected in human faeces collected from a number of cities, providing evidence of human ingestion of microplastics and their presence in the gastrointestinal tract. Here, using Raman spectroscopy, we identified an average of 50 particles g -1 (20.4-138.9 particles g -1 wet weight) in faeces collected from a healthy cohort in Hong Kong. This quantity was about five times higher than the values reported in other places in Asia and Europe. Polystyrene was the most abundant polymer type found in the faeces, followed by polypropylene and polyethylene. These particles were primarily fragments, but about two-thirds of the detected polyethylene terephthalate were fibres. More than 88% of the microplastics were smaller than 300 µm in size. Our study provides the first data on the faecal level, and thus the extent of ingestion, of microplastics in Hong Kong's population. This timely assessment is crucial and supports the recently estimated ingestion rate of microplastics by Hong Kong residents through seafood consumption, which is one of the highest worldwide. These findings may be applicable to other coastal populations in South China with similar eating habits.

Intertidal and estuarine bivalves are adapted to fluctuating environmental conditions but the cellular adaptive mechanisms under combined stress scenarios are not well understood. The Hong Kong oysters Crassostrea hongkongensis experience periodic hypoxia/reoxygenation and salinity fluctuations during tidal cycles and extreme weather, which can negatively affect the respiratory organs (gills) involved in oxygen uptake and transport. We determined the effects of periodic hypoxia under different salinities on the oxidative stress response in Hong Kong oysters. Oxidative stress parameters (activities of superoxide dismutase (SOD), and catalase (CAT), tissue levels of malondialdehyde (MDA) and protein carbonyl content (PCC)) were determined in the gills of oysters exposed to diel-cycling hypoxia (hypoxia at night: 12h at 2 mg/L, reoxygenation: 12h at 6 mg/L) and normal dissolved oxygen (DO) (6 mg/L) under three salinities (10, 25, and 35‰) for 28 days. Oxygen regime in combination with salinity changes had significant interactive effects on all studied parameters except SOD. Salinity, DO and their interactions increased PCC after 14 and 28 days of exposure, and the combination of hypoxia/reoxygenation and decreased salinity showed the most severe effect. MDA content of the gills increased only after the long-term (28 days) exposure in decreased or increased salinity under normal DO treatments, showing PCC was more sensitive than MDA as biomarker of oxidative stress. Low salinity suppressed SOD activity regardless of the DO, whereas hypoxia induced SOD responses. CAT activities decreased significantly under high salinity with hypoxia/reoxygenation conditions. Our findings highlighted that periodic hypoxia/reoxygenation with salinity change induced antioxidant responses, which can impact the health of Hong Kong oyster C. hongkongensis and prolonged salinity stress may be one reason for the mortality during its aquaculture process., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The accumulation process of microplastics (MPs) is a key to understanding their fate in the environment. However, there is limited information about the short-term accumulation of MPs on macrophytes. The ability of macrophyte to attenuate wave and reduce current velocity is potentially facilitating MPs deposition. We hypothesize that the macroalgae retain MPs with their morphologies (filamentous and non-filamentous) being one of the factors to govern retention. Our hypothesis was tested by field observation during the dry season in Hong Kong when the macroalgae communities were the most diverse. MPs per biomass, surface area, or interstitial volume were used to represent the abundances on macroalgae. We found that filamentous algae retained a 2.35 times higher number of MPs when compared with non-filamentous algae if unit per biomass was considered. Other units, however, showed insignificant differences in MPs abundances between algal morphologies. Fibre was the most dominant shape of MPs with no significant difference in their abundances between filamentous and non-filamentous algae, suggesting fibres were retained regardless of the algal morphologies. To further evaluate the potential accumulation in the environment, sediment samples were also collected under the algal mat and immediate vicinity (~50 cm) of the algal mat. We found that sediment collected under the vegetated area contained significantly higher MPs. This was 3.39 times higher than the unvegetated area. Sediment collected under/near filamentous algae retained much higher abundances of MPs than those of non-filamentous algae. Provided that the observed retention of MPs on macroalgae, we speculate macrophyte system is one of the short-term MPs accumulation hotspots where the temporal increase of MPs depends on the seasonality of macrophyte in a given region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Purpose: We aimed to evaluate the impact of preoperative local symptoms on prognosis after radical nephroureterectomy in patients with upper tract urothelial carcinoma (UTUC)., Methods: This retrospective study consisted of 2,662 UTUC patients treated at 15 institutions in Taiwan from 1988 to 2019. Clinicopathological data were retrospectively collected for analysis by the Taiwan UTUC Collaboration Group. The Kaplan-Meier method was used to calculate overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), and bladder recurrence-free survival (BRFS). The prognostic value of preoperative local symptoms in OS, CSS, DFS, and BRFS was investigated using Cox proportional hazards models., Results: The median follow-up was 36.6 months. Among 2,662 patients, 2,130 (80.0%) presented with hematuria and 398 (15.0%) had symptomatic hydronephrosis at diagnosis. Hematuria was associated with less symptomatic hydronephrosis ( p < 0.001), more dialysis status ( p = 0.027), renal pelvic tumors ( p < 0.001), and early pathological tumor stage ( p = 0.001). Symptomatic hydronephrosis was associated with female patients ( p < 0.001), less dialysis status ( p = 0.001), less bladder cancer history ( p < 0.001), ureteral tumors ( p < 0.001), open surgery ( p = 0.006), advanced pathological tumor stage ( p < 0.001), and postoperative chemotherapy ( p = 0.029). Kaplan-Meier analysis showed that patients with hematuria or without symptomatic hydronephrosis had significantly higher rates of OS, CSS, and DFS (all p < 0.001). Multivariate analysis confirmed that presence of hematuria was independently associated with better OS (HR 0.789, 95% CI 0.661-0.942) and CSS (HR 0.772, 95% CI 0.607-0.980), while symptomatic hydronephrosis was a significant prognostic factor for poorer OS (HR 1.387, 95% CI 1.142-1.683), CSS (HR 1.587, 95% CI 1.229-2.050), and DFS (HR 1.378, 95% CI 1.122-1.693)., Conclusions: Preoperative local symptoms were significantly associated with oncological outcomes, whereas symptomatic hydronephrosis and hematuria had opposite prognostic effects. Preoperative symptoms may provide additional information on risk stratification and perioperative treatment selection for patients with UTUC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yeh, Chang, Fang, Chen, Lin, Hong, Huang, Wang, Chen, Lo, Yu, Tseng, Lin, Jou, Cheong, Jiang, Tsai, Hsueh, Chen, Huang, Tsai, Lin, Wu, Lin, Lin and Wu.)

Microplastics have become a significant environmental problem worldwide. Compared with microplastics, nanoplastics are apparently more abundant and harmful but their environmental processes are less well understood. The fate and ecological impacts of nanoplastics in aquatic environments are largely determined by their aggregation properties, which were investigated here using pure water and artificial seawater prepared in the laboratory, as well as river water and coastal seawater collected from subtropical Hong Kong. The tests were carried out at an environmentally realistic temperature range (15-35 °C) with particle concentrations over four orders of magnitude (0.1-100 mg L -1 ). Under these experimental conditions, parameters of dynamic light scattering were used to determine the extent of aggregation and colloidal stability of polystyrene nanospheres (nPS), a common test model of nanoplastics. Our results showed that aggregation of nPS was minimal in pure water and river water, but became strong under the ionic strength of artificial seawater and coastal seawater, in which 70 nm nPS could aggregate to > 2000 nm, and this aggregation clearly increased with increase in temperature and particle concentration. The aggregates with increasing size and decreasing colloidal stability were deposited more quickly. Findings from this study imply an increased risk of nanoplastics to marine benthic organisms through the aggregation and deposition processes, particularly in warmer waters., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The present study compared the relative significance of prey consumption and respiration as routes of microplastic (MP) intake in a carnivorous muricid gastropod, Reishia clavigera. The time-dependent accumulation of MPs within 14-day exposure and their removal through depuration were also investigated for two forms of MPs (fibre, fragment) at an environmentally relevant concentration (10 items L -1 ) and two higher concentrations (100 and 1000 items L -1 ). At 1000 items L -1 , the number of MPs in R. clavigera on Day 14 was 1.8 ± 0.2 fibres individual -1 or 0.8 ± 0.3 fragments individual -1 , equivalent to 64.6% of the fibres or 9.4% of the fragments retained by the variable mussel Brachidontes variabilis, a prey of R. clavigera. Consumption of B. variabilis was the most important route of MP intake in R. clavigera, although a small number of MPs were adhered to the gills during ventilation. Depuration in clean seawater without MPs was very effective in eliminating MPs in the body of R. clavigera but the possibility of long-term bioaccumulation of MPs could not be ruled out. The high percentage of MPs transferred from the prey to predator indicates the potential of trophic transfer as a significant route of uptake for MPs in higher predators., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Microplastic pollution is a major threat to the marine environment attracting attention from scientific and public communities. Although we have sufficient evidence that microplastic is ubiquitous in all ecosystems, the question of the harmfulness of microplastic exposure is still under debate. Filter feeders like bivalves are commonly exposed to microplastics in water and sediments and thus can serve as excellent biological indicators for microplastic pollution. A relatively rich toxicological literature has been focusing on microplastic effects on bivalves but we have yet to reach an agreement on the toxic effects and mechanisms of microplastics. Here, we conducted a meta-analysis and bibliometrics analysis of the microplastic studies in bivalves. The bibliometric analysis (used to evaluate the general research trends) showed that the investigation of microplastic distribution in the marine environment and the molecular mechanisms of microplastic toxicity are the two major hot spots of research. Based on analyses of ecologically and environmentally relevant microplastics concentrations, particle sizes and polymer types, we discuss the physiological effects of microplastics on bivalves, and the severity and direction of the effects at the cellular, tissue, organ and organismal levels. The meta-analysis results show that microplastics can induce time-dependent oxidative stress in bivalves. Generally, the activities of antioxidant enzymes, such as glutathione peroxidase (GPx), glutathione-S-transferase (GST) and superoxide dismutase (SOD) increased during short-term exposure but declined after long-term exposure to microplastics. Non-linear response of GPx, GST and SOD enzymes to MP exposure over time indicate that these enzymes are not good biomarkers of MPs effects in marine bivalves. The tissue glutathione levels and catalase (CAT activity) showed an increase during both short- and long term MP exposures and thus can be used as oxidative stress biomarkers of sublethal MPs effects in marine bivalves., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The prevalence of microplastics in water bodies such as oceans and rivers has received considerable attention in recent years. The present study contributes to this research effort by assessing microplastics in 12 remote lakes on the Tibetan Plateau, China. Despite the limited extent of human activities, at least 17 items and up to 2644 items of microplastics were found per kg of dried sediments collected from the lakes in Tibet. These values were considered high compared to the levels of microplastics reported in other lake areas worldwide. Our results showed that the most prevailing types of microplastics in the sediments were black or transparent fibers in the size range of 0.05-0.5 mm, which were mainly identified to be polyamide and polyethylene terephthalate using Fourier-transform infrared microspectroscopy. The number of microplastics found appeared to be higher in sediments with a higher silt and clay content. Atmospheric long-range transport, glacial meltwater and surface runoff represent potential pathways to carry microplastics from elsewhere to the remote lakes in Tibet. This study shall be of great significance in understanding the transport and distribution of microplastics in the environment at regional or global scale., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this study, we report the use of nanobubbles (NBs) as a simple and facile approach to effectively delay scaling in membrane distillation (MD) during the treatment of highly saline feed (100 g L -1 ). Unlike conventional gas bubbling in MD for improving the hydrodynamic flow conditions in the feed channel, here we generated air NBs with an average size of 128.81 nm in the feed stream and examined their impact on membrane scaling inhibition during MD operation. Due to their small size, neutral buoyancy, and negative surface charge, NBs remain in suspension for a longer time (14 days), providing homogenous mixing throughout the entire feed water. The MD performance results revealed that severe membrane scaling happened during the DCMD treatment of high salinity brine in the absence of nanobubbles, which dramatically reduced the distillate flux to zero after 13 h. A one-time addition of air NBs in the saline feed significantly reduced salt precipitation and crystal deposition on the PVDF membrane surface, delayed the occurrence of flux decline, prevented membrane wetting, thereby prolonging the effective MD operating time. With similar feed concentration and operating conditions, only 63% flux decline after 98 h operation was recorded in nanobubble-assisted MD. Two key explanations were suggested for the delayed membrane scaling upon addition of air NBs in the MD feed: (1) NB-induced turbulent flow in the feed channel that increases the surface shear forces at the membrane surface, alleviating both temperature and concentration polarization effect, (2) electrostatic attractions of the counterions to the negatively charged NBs, which reduces the availability of these ions in the bulk feed for scale formation., (Copyright © 2021. Published by Elsevier Ltd.)

Anthropogenic elevation of atmospheric carbon dioxide (CO 2 ) drives global-scale ocean acidification (OA), which has aroused widespread concern for marine ecosystem health. The tri-spine horseshoe crab (HSC) Tachypleus tridentatus has been facing the threat of population depletion for decades, and the effects of OA on the physiology and microbiology of its early life stage are unclear. In this study, the 1st instar HSC larvae were exposed to acidified seawater (pH 7.3, pH 8.1 as control) for 28 days to determine the effects of OA on their growth, molting, oxidative stress, and gut microbiota. Results showed that there were no significant differences in growth index and molting rate between OA group and control group, but the chitinase activity, β-NAGase activity, and ecdysone content in OA group were significantly lower than those of the control group. Compared to the control group, reactive oxygen species (ROS) and malondialdehyde (MDA) contents in OA group were significantly increased at the end of the experiment. Superoxide dismutase (SOD), catalase (CAT), and alkaline phosphatase (AKP) activities increased first and then decreased, glutathione peroxidase (GPX) decreased first and then increased, and GST activity changed little during the experiment. According to the result of 16S rRNA sequencing of gut microbiota, microbial-mediated functions predicted by PICRUSt showed that "Hematopoietic cell lineage," "Endocytosis," " Staphylococcus aureus infection," and "Shigellosis" pathways significantly increased in OA group. The above results indicate that OA had no significant effect on growth index and molting rate but interfered with the activity of chitinolytic enzymes and ecdysone expression of juvenile horseshoe crabs, and caused oxidative stress. In addition, OA had adverse effects on the immune defense function and intestinal health. The present study reveals the potential threat of OA to T. tridentatus population and lays a foundation for the further study of the physiological adaptation mechanism of juvenile horseshoe crabs to environmental change., Competing Interests: JS is employed by Tianjin Era Biology Technology Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liu, Liu, Xiong, Zhang, Fang, Song, Tai, Zhu, Hu and Wang.)

Microplastics represent an emerging environmental issue and have been found almost everywhere including seafood, raising a great concern about the ecological and human health risks they pose. This study addressed the common technical challenges in the assessment of microplastics in seafood by developing an improved protocol based on Raman spectroscopy and using the green-lipped mussel Perna viridis and the Japanese jack mackerel Trachurus japonicus as the test models. Our findings identified a type of stainless-steel filter membranes with minimal Raman interference, and a combination of chemicals that achieved 99-100% digestion efficiency for both organic and inorganic biomass. This combined chemical treatment reached 90-100% recovery rates for seven types of microplastics, on which the surface modification was considered negligible and did not affect the accuracy of polymer identification based on Raman spectra, which showed 94-99% similarity to corresponding untreated microplastics. The developed extraction method for microplastics was further combined with an automated Raman mapping approach, from which our results confirmed the presence of microplastics in P. viridis and T. japonicus collected from Hong Kong waters. Identified microplastics included polypropylene, polyethylene, polystyrene and poly(ethylene terephthalate), mainly in the form of fragments and fibres. Our protocol is applicable to other biological samples, and provides an improved alternative to streamline the workflow of microplastic analysis for routine monitoring purposes., (Copyright © 2021. Published by Elsevier Ltd.)