Study on the diversity and germination of dinoflagellate cysts in the sediments of foreign ships in Shanghai Port.

The dinoflagellate cysts present in the ballast water sediment of foreign ships in Shanghai Port have not been previously studied. Therefore, sediment samples were collected from the ballast water of 16 foreign ships in Shanghai Port, and the types of dinoflagellate cysts were identified and their abundance was calculated, with a specific focus on the analysis of toxic and harmful dinoflagellates. Moreover, simulations of temperature and salinity conditions throughout the year in the Shanghai port waters were conducted to carry out dinoflagellate cyst germination experiments, with analyze and compare the germinated dinoflagellate cysts under different conditions. Dinoflagellate cysts were found in 100 % of the ship sediment samples, including a total of 9 species of toxic and harmful dinoflagellate cysts. In the germination experiment, 15 °C was found to be the optimal temperature for the germination of dinoflagellate cysts in ballast water sediment, and high salinity is more favorable for cyst germination.

Lactobacillus crispatus 7-4 Mitigates Salmonella typhimurium-Induced Enteritis via the γ­Glutamylcysteine-Mediated Nrf2 Pathway.

Salmonella typhimurium (S. typhimurium) constitutes a major public health concern. We have previously proven that Lactobacillus crispatus 7-4 (L. crispatus 7-4) can inhibit the growth of S. typhimurium and thus can be used as a biocontrol strategy to suppress foodborne S. typhimurium infections. However, the inhibitory effect and in-depth mechanism of L. crispatus 7-4 remain to be elucidated. In this study, we found that L. crispatus 7-4 can protect against S. typhimurium-induced ileum injury by promoting intestinal barrier integrity, maintaining intestinal mucosal barrier homeostasis, and reducing intestinal inflammatory response. Furthermore, we demonstrated that this probiotic strain can increase the abundance of Lactobacillus spp. to maintain microbial homeostasis and simultaneously increase the amount of γ­glutamylcysteine (γ-GC) by activating the glutathione metabolic pathway. The increased γ-GC promoted the transcription of Nrf2 target genes, thereby improving the host antioxidant level, reducing reactive oxygen species (ROS) accumulation, and removing pro-inflammatory cytokines. In other words, L. crispatus 7-4 could activate the enterocyte Nrf2 pathway by improving γ-GC to protect against S. typhimurium-induced intestinal inflammation and oxidative damage.

Design and validation of a sampling skid device for collecting aquatic organisms.

As international regulations on aquatic organism discharge in ships' ballast water take effect, port state authorities will need a sampling device for compliance inspectors to potentially use for sample collection. Importantly, the device must be easily operable, quickly connectable to the main ballast water pipe, and reliable in collecting a representative sample of the ballast water flowing through the pipe. Existing sampling devices currently fall short in these aspects. Therefore, we've developed, manufactured, and validated a new sampling skid. This design enables the regulation of flow velocity and flow rate, facilitating the simultaneous, convenient collection of organisms ≥50 µm and other biological samples. In this study, we conducted a comparative analysis of sampling outcomes between traditional net sampling devices, using land-based experiments to assess the accuracy and precision of the innovative sampling skid. The findings show that, despite significant differences in <10 µm organism concentrations, the sampling skid, as an alternative to traditional net and other skid devices, has demonstrated substantial potential and feasibility.

Microencapsulate Probiotics (MP) Promote Growth Performance and Inhibit Inflammatory Response in Broilers Challenged with Salmonella typhimurium.

Antibiotic-resistant bacteria are prevalent in husbandry around the world due to the abuse of antibiotic growth promoters (AGPs); therefore, it is necessary to find alternatives to AGPs in animal feed. Among all the candidates, probiotics are promising alternatives to AGPs against Salmonella infection. The anti-Salmonella effects of three probiotic strains, namely, Lactobacillus crispatus 7-4, Lactobacillus johnsonii 3-1, and Pediococcus acidilactici 20-1, have been demonstrated in our previous study. In this study, we further obtained the alginate beads containing compound probiotics, namely, microencapsulate probiotics (MP), and evaluated its regulatory effect on the health of broilers. We incubated free and microencapsulate probiotics in simulated gastric and intestinal juice for 2 h, and the results showed that compared to free probiotics, encapsulation increased tolerance of compound probiotics in the simulated gastrointestinal condition. We observed that the application of probiotics, especially MP, conferred protective effects against Salmonella typhimurium (S.Tm) infection in broilers. Compared to the S.Tm group, the MP could promote the growth performance (p < 0.05) and reduce the S.Tm load in intestine and liver (p < 0.05). In detail, MP pretreatment could modulate the cecal microflora and upregulate the relative abundance of Lactobacillus and Enterobacteriaceae. Besides, MP could reduce the inflammation injury of the intestine and liver, reduce the pro-inflammatory cytokines (IL-6, TNF-α, IL-1ß) expression, and induce of anti-inflammatory cytokine (IL-10) expression. Furthermore, MP could inhibit NLRP3 pathway in ileum, thereby attenuating S.Tm-induced inflammation. In conclusion, MP could be a new feeding supplementation strategy to substitute AGPs in poultry feeding.

Synthesis and biological evaluation of capsaicin analogues as antioxidant and neuroprotective agents.

Capsaicin and its analogues 3a-3q were designed and synthesized as potential new antioxidant and neuroprotective agents. Many analogues exhibited good antioxidant effects, and some showed more potent free radical scavenging activities than the positive drug quercetin (IC50 = 8.70 ± 1.75 µM for DPPH assay and 13.85 ± 2.87 µM for ABTS assay, respectively). The phenolic hydroxyl of capsaicin analogues was critical in determining antioxidant activity. Among these compounds, 3k displayed the most potent antioxidant activity. Cell vitality tests revealed that the representative compound 3k was good at protecting cells from H2O2-induced oxidative damage at low concentrations (cell viability increased to 90.0 ± 5.5% at 10 µM). In addition, the study demonstrated that 3k could reduce intracellular ROS accumulation and increase GSH levels to prevent H2O2-induced oxidative stress in SY5Y cells. In the mitochondrial membrane potential assay, 3k significantly increased the MMP level of SY5Y cells treated with H2O2 and played an anti-neuronal cell death role. These results provide a promising strategy to develop novel capsaicin analogues as potential antioxidant and neuroprotective agents.

Recommendations for representative sampling methodologies in ballast water: A case study from the land-based test.

Accurate assessment of ballast water's community composition and organism concentrations is crucial for effective management. Yet, the lack of standardized global sampling methods presents challenges to achieving this objective. Inconsistencies hinder data comparison across regions and vessels, impeding efficient ballast water treatment and discharge regulation. This study conducted land-based tests to establish suitable methodologies. For organisms ≥50 µm and ≥10 µm to <50 µm, the recommended max flow rate is 50 L/min; for <10 µm organisms, 25 L/min is advised to prevent cell damage. Sampling should cover substantial discharge durations. To ensure representation, ≥50 µm organisms require ≥1m3, while ≥10 µm to <50 µm and <10 µm organisms need 20 L. The ultimate aim is standardized methods for assessing ballast water across regions and vessel types, facilitating effective management to curb invasive species and protect aquatic ecosystems.

Comparison of heavy metal pollution and ecological risk assessment in ballast tank sediments based on two applicable reference standards.

The potential risks of ballast tank sediments have garnered global attention. This study collected sediment samples from ballast tanks of four transoceanic ships and determined 27 metal(loid) s by GB 5085.6-2007 and 9 metal(loid)s by GB 18668-2002. The pollution characteristics and ecological risk assessment of 8 typical heavy metals measured by both standards were analyzed and compared. Concentrations of Cd, Zn, and As were found to be high in the ballast tank sediments, and attention should also be directed toward Sn and Mn, which were rarely studied in ballast tank sediments. The concentration of Ni had significant differences between the two standards (P < 0.05). The results of ecological risk methods indicate that Cd, Zn, and As pose significant ecological risks. GB 5085.6-2007 demonstrated sensitivity in reflecting the ecological risks of heavy metals. Overall, this study provides valuable insights into establishing a unified standard for heavy metals for future ballast tank sediment management.

Evaluate the compliance of ballast water management system on various types of operational vessels based on the D-2 standard.

The transfer of ship ballast water poses significant risks to the aquatic ecosystem and human health. To mitigate the influences of non-native species, ballast water management systems (BWMS) have been installed on international ships to ensure proper treatment of ballast water before discharge. This study investigates whether ballast water discharges managed by BWMS meet the requirements of the D-2 standard for organisms in different size classes. Representative ballast water samples were collected from 28 ships (a total of 20 different BWMS) arriving in Shanghai during the period 2020-2022. Results have shown that two samples (7.1 %) exceeded the D-2 Standard. The compliance rates varied among different vessel types, with cargo vessels achieving a compliance rate of 81.8 %, while LNG vessels and container vessels achieved 100 % compliance. The potential to achieve higher levels of ballast water management will increase as crews improve their skills in operating BWMS and BWMS is further developed.

Bloom forming species transported by ballast water under the management of D-1 and D-2 standards-Implications for current ballast water regulations.

Ballast water (BW) is a well-known transporter for introducing non-indigenous aquatic organisms. To reduce such risks associated with BW discharge, the International Maritime Organization (IMO) adopted the International Convention for the Control and Management of Ships' Ballast Water and Sediments (BWM Convention). We examined the abundance and diversity of bloom forming species in BW under the management of Regulation D-1 Ballast Water Exchange Standard and D-2 Ballast Water Performance Standard. The abundance and richness of bloom forming species were also examined in relation to ballast water age. Our findings indicate the abundance and diversity of bloom forming species were significantly lower in BW under the management of D-2 standard than that under D-1 standard. The abundance and richness represent no statistically significant correlation with BW age (p = 0.76 and p = 0.43, respectively). Some resistant species persist in ballast water. Thereby, we further provide some advice to overcome the existing challenges for the implementation of the Regulation D-2.

The dispersal of dinoflagellate cyst caused by international ships under repair conditions: a potential invasion risk to the Yangtze River Estuary, China.

The foreign dinoflagellate cysts in ships' ballast water tank sediments (BWTS) can be viable for a long time under hostile storage conditions. It is crucial to understand the detailed mechanisms of harmful biological invasions in estuary ecosystems. To study the relationship between the abundance of dinoflagellate cysts and environmental factors, cyst assemblages were analyzed in 7 sediment samples, collected from one international commercial ship that arrived in Shanghai in August 2020. Twenty-three dinoflagellate cyst taxa were identified in 5 groups, including autotrophic (9) and heterotrophic (14) species. Distribution of dinoflagellate cysts in the different ballast water tanks is heterogeneous. Dinoflagellate cysts in BWTS of the repaired ship were dominated by Scrippsiella acuminata, Protoperidinium leonis, Protoperidinium oblongum, Lingulodinium polyedra, Alexandrium tamarense/A. catenella, Protoperidinium pentagonum, and Protoperidinium subinerme. The abundance of the dinoflagellate cysts in each tank ranged from 80.69 to 330.85 cysts g-1 DS (dry sediment). Multivariate statistical analyses revealed that the variation in cysts from different tanks had positive correlations with total nitrogen (TN), total phosphorus (TP), and pH and negative correlations with total organic carbon (TOC) except for sample TK5. For germination of dinoflagellate cysts in BWTS, 12 species were germinated in 40 days and cysts of potentially toxic dinoflagellate species were more abundant than those of non-toxic species. Results show that potentially viable and harmful/toxic dinoflagellate cysts are present in BWTS of ships arriving in Shanghai, China. Consequently, knowledge obtained in this study can be valuable for further managing of potential biological invasion of the Yangtze River Estuary.

CCL4 participates in the reprogramming of glucose metabolism induced by ALV-J infection in chicken macrophages.

Interferon and chemokine-mediated immune responses are two general antiviral programs of the innate immune system in response to viral infections and have recently emerged as important players in systemic metabolism. This study found that the chemokine CCL4 is negatively regulated by glucose metabolism and avian leukosis virus subgroup J (ALV-J) infection in chicken macrophages. Low expression levels of CCL4 define this immune response to high glucose treatment or ALV-J infection. Moreover, the ALV-J envelope protein is responsible for CCL4 inhibition. We confirmed that CCL4 could inhibit glucose metabolism and ALV-J replication in chicken macrophages. The present study provides novel insights into the antiviral defense mechanism and metabolic regulation of the chemokine CCL4 in chicken macrophages.

Assessing the effectiveness of filtration + UV-C radiation for the treatment of simulated ballast water at various holding times.

In recent years, the issue of invasive alien species brought on by ballast water has drawn increasing attention, and advances in ballast water treatment technologies have been made. One of the most popular combined ballast water treatment technologies utilized in ballast water management systems (BWMSs) globally is filtration + UV-C radiation. During the actual voyage of the ship, ballast water is treated by the BWMS and then enters the dark ballast tanks until the ballast water is discharged. Marine organisms are able to complete DNA damage caused by UV radiation in dark ballast tanks. Therefore, the length of holding time affects the effectiveness of the BWMS in treating ballast water. The objective of this study was to examine the efficacy of filtration + UV-C irradiation treatment at different holding times for the removal or inactivation of phytoplankton and zooplankton populations during simulated ballast water treatment. Results indicate that the holding time after the filtration + UV-C radiation treatment increased the inactivating efficacy, especially for zooplankton in natural seawater. For phytoplanktons in ballast water, the strongest impact on the treatment efficacy was reached with a holding time of 24 h.

Toxicity evaluation of chlorinated natural water using Photobacterium phosphoreum: Implications for ballast water management.

Chlorination of ballast water could produce harmful disinfection by-products (DBPs) and total residual oxidants. The International Maritime Organization calls for toxicity testing of discharged ballast water with fish, crustacea and algae to reduce the risk, but it is difficult to evaluate the toxicity of treated ballast water in a short time. Therefore, the purpose of this study was to analyze the applicability of luminescent bacteria to the assessment of residual toxicity of chlorinated ballast water. The toxicity unit for all treated samples were higher for Photobacterium phosphoreum than for microalgae (Selenastrum capricornutum and Chlorella pyrenoidosa), after adding neutralizer, all samples showed little effect on the luminescent bacteria and microalgae. For the DBPs, except for 2,4,6-Tribromophenol, Photobacterium phosphoreum could produce more sensitive and rapid test results than other species, the results in Photobacterium phosphoreum showed that the toxicity of DBPs in order of: 2,4-Dibromophenol > 2,6-Dibromophenol > 2,4,6-Tribromophenol > Monobromoacetic acid > Dibromoacetic acid > Tribromoacetic acid, and most binary mixtures (aromatic DBPs and aliphatic DBPs) presented synergistic effects based on the CA model. The aromatic DBPs in ballast water deserve more attention. In general, for ballast water management, the use of luminescent bacteria to evaluate the toxicity of treated ballast water and DBPs is desirable, this study could provide beneficial information for enhancing ballast water management.

Study on the effectiveness of membrane separation + N2 deoxidation process for the treatment of bacteria in ballast water.

Effects of the membrane separation + N2 deoxidation process on the abundance and activity of bacteria were examined under two salinity conditions at Yangshan Port, Shanghai, China. Sequencing of 16S rRNA gene amplicons demonstrated a decrease in the diversity and activity of bacteria in fresh water and marine water, with a total removal rate of approximately 63 % and 69 %, respectively. Indicator bacteria decreased to 10 CFU·100 mL-1, which met the IMO D-2 standard. A total of 13 potential pathogens were detected after treatment, indicating that there is still a risk of pathogenic bacteria invasion in the discharge water, particularly marine bacteria, and that the D-2 standard may be insufficient as a preventive measure against pathogenic bacteria transfer. The results will provide reference for government supervision, and will also be important for monitoring foreign bacteria and technology development.

Activation of lnc-ALVE1-AS1 inhibited ALV-J replication through triggering the TLR3 pathway in chicken macrophage like cell line.

Endogenous retroviruses (ERVs) are remnants of the historical retroviral infections, and their derived transcripts with viral signatures are important sources of long noncoding RNAs (lncRNAs). We have previously shown that the chicken ERV-derived lncRNA lnc-ALVE1-AS1 exerts antiviral innate immunity in chicken embryo fibroblasts. However, it is not clear whether this endogenous retroviral RNA has a similar function in immune cells. Here, we found that lnc-ALVE1-AS1 was persistently inhibited in chicken macrophages after avian leukosis virus subgroup J (ALV-J) infection. Furthermore, overexpression of lnc-ALVE1-AS1 significantly inhibited the replication of exogenous ALV-J, whereas knockdown of lnc-ALVE1-AS1 promoted the replication of ALV-J in chicken macrophages. This phenomenon is attributed to the induction of antiviral innate immunity by lnc-ALVE1-AS1 in macrophages, whereas knockdown of lnc-ALVE1-AS1 had the opposite effect. Mechanistically, lnc-ALVE1-AS1 can be sensed by the cytosolic pattern recognition receptor TLR3 and trigger the type I interferons response. The present study provides novel insights into the antiviral defense of ERV-derived lncRNAs in macrophages and offers new strategies for future antiviral solutions.

Structural basis of the acyl-transfer mechanism of human GPAT1.

Glycerol-3-phosphate acyltransferase (GPAT)1 is a mitochondrial outer membrane protein that catalyzes the first step of de novo glycerolipid biosynthesis. Hepatic expression of GPAT1 is linked to liver fat accumulation and the severity of nonalcoholic fatty liver diseases. Here we present the cryo-EM structures of human GPAT1 in substrate analog-bound and product-bound states. The structures reveal an N-terminal acyltransferase domain that harbors important catalytic motifs and a tightly associated C-terminal domain that is critical for proper protein folding. Unexpectedly, GPAT1 has no transmembrane regions as previously proposed but instead associates with the membrane via an amphipathic surface patch and an N-terminal loop-helix region that contains a mitochondrial-targeting signal. Combined structural, computational and functional studies uncover a hydrophobic pathway within GPAT1 for lipid trafficking. The results presented herein lay a framework for rational inhibitor development for GPAT1.

Polycyclic aromatic hydrocarbons in surface water and sediment from Shanghai port, China: spatial distribution, source apportionment, and potential risk assessment.

The spatial distribution, sources, and potential risk of polycyclic aromatic hydrocarbons (PAHs) were systematically investigated in Shanghai port, one of the most important hubs in international trade. The 16 priority PAHs in surface water and sediment were determined. Total concentrations of 16 PAHs (Σ16PAHs) ranged from 140.6 to 647.4 ng/L in surface water and from 12.7 to 573.2 ng/g (dry weight, dw) in sediment, respectively. The 2-ring and 3-ring PAHs with low molecular weight were main components in water, while the 3-ring and 4-ring PAHs were abundant in sediment. Flu was the main component of the Σ16PAHs in water and sediment. According to the source apportionment, the PAHs in water mostly originated from combustion of fossil fuels and petroleum and petroleum combustion were the main contributors to the PAHs in sediment. The results obtained from potential risk assessment indicate that the PAHs in surface water present a moderate ecological risk, whereas the PAHs in sediment show low ecological risk indicating a less possibility of toxic pollution.

The occurrence of potential pathogenic bacteria on international ships' ballast water at Yangshan Port, Shanghai, China.

Ballast water is a primary vector for the global transfer of non-indigenous species, which threaten the balance of aquatic ecosystems. The second-generation high-throughput sequencing (HTS) and culture method (by the first-generation sequencing technology) were used to explore pathogens in ballast water from international ships on the routes of China-Australia (AU), China-Europe (E) and China-America (AM). No significant differences in dominant bacteria among ballast water samples from different routes. Thirty-four pathogens were detected in all samples by HTS, including Acinetobacter lwoffii, Brevundimonas vesicular and Pseudomonas sp., etc., while nine pathogens were detected by culture, including Pseudoalteromonas piscicida, Rhodococcus erythropolis and Vibrio alginolyticus, etc. All ballast water carried a potential bacteriological risk to Yangshan Port. The abundance of pathogens was significant affected by holding time, temperature, salinity and NH4. Detection of pathogens as much as possible through different technologies is desirable, more pathogens could provide beneficial information for enhancing ballast water management.

Lactobacillus crispatus-derived exopolysaccharides with antibacterial activity limit Salmonella typhimurium invasion by inhibiting inflammasome-mediated pyroptosis.

In this study, a novel heteropolysaccharide (EPS 7-4) with a molecular weight of 53 387 Da was isolated from Lactobacillus crispatus, and it was mainly composed of mannose (36.9%) and glucose (30.8%). EPS 7-4 showed excellent inhibitory effects on the proliferation, biofilm formation, and virulence factor gene expression of Salmonella typhimurium (S. typhimurium) by disrupting the integrity of the bacterial wall. Furthermore, EPS 7-4 can effectively restrict bacterial translocation, upregulate the abundance of Lactobacillus spp. and Bifidobacterium spp., and alleviate the S. typhimurium induced severe inflammatory response in the intestinal tract of mice. Besides, we demonstrated that EPS 7-4 can protect mice by inhibiting S. typhimurium induced pyroptosis, with the mechanism that EPS 7-4 affects ASC oligomerization during inflammasome-mediated pyroptosis. Therefore, due to its excellent anti-bacterial and anti-inflammatory abilities, EPS 7-4 is a promising health regulator owing to its excellent antibacterial and anti-inflammatory abilities.

Study on spatial distribution, potential sources and ecological risk of heavy metals in the surface water and sediments at Shanghai Port, China.

Heavy metal concentrations in surface waters and sediments of Shanghai port were measured to analyze the spatial distribution characteristics, sources and pollution degrees. The southern Shanghai port was heavily polluted by Cd, Pb, Cr and Cu in water, and the concentrations of Pb, Hg and Zn in sediments exceeded Effects Range Low. Cu, Pb, Cd and Cr in water were positively correlated in group, and they probably derived from industrial and domestic sewage, fossil fuel burning and vehicular pollution and represented 82.47 % of the contribution. Zn, Hg and As contaminations represented industrial and agricultural effluent sources and accounted for the remaining 17.53 %. Heavy metal pollution of Yangshan Port water was at high pollution, and the remaining sites were at low pollution. Most of the sampling sites were at moderate ecological risk in sediments, and the pollution of Cd, Hg and Zn were serious.