How does bivalve size influence microplastics accumulation?

Microplastics (wasted plastic particles < 5 mm in diameter) are ubiquitously distributed in the marine environment. Filter-feeding and low trophic level bivalves are vulnerable to microplastics accumulation from the surrounding depositional environment, thereby threatening both ecological health and human food safety. Microplastics had been detected in lots of coastal Bivalvia species. However, the influence of biological morphology on the mechanism of microplastics accumulation is not clear. There is also a knowledge gap of which species are preferred for commercial consumption, which creates loopholes in risk identification for food safety. A survey on a commercial popular eaten but under-researched hard clam (Meretrix meretrix; Linnaeus, 1758) from a famous fishery port city in southern China was carried out to comprehensively analyze shell size influence on microplastics accumulation in bivalves and consequently, human intake risk via bivalve consumption. Detected microplastics count in per individual (MCI) was 24.64 ± 19.11 items · individual-1, and microplastics count per gram (MCG; wet weight with shell) was 0.66 ± 0.54 items · g-1. When the shell width grew by 1 mm, MCI increased by 1.01 times, but MCG decreased by 0.97 times. Dominant microplastics characteristics found in this study was fiber and fragment. Sizes ranged from 25 to 150 µm, and dark colors (black, red, and blue) were found. The mostly common polymers were polyethene (PE, 40%), polyethylene terephthalate (PET, 23%), and polypropylene (PP, 18%). Estimated annual intake (EAI) risk of microplastics via hard clam consumption by residents was 6652.26 ± 5327.28 items · year -1 · person -1. The microplastics in bivalves and EAI was relatively high. When shell width grew by 1 mm, EAI decreased by 0.97 times. Therefore, eating a fixed amount of larger hard clams with a relatively low amount of microplastics can reduce EAI risk for consumers. A systematic investigation of emission sources along main coast, where bivalve production is prominent will be useful for food safety control in this region.

Extraction, structural characterization, and antioxidant and immunomodulatory activities of a polysaccharide from Notarchus leachii freeri eggs.

The crude polysaccharides (NLCEP) were extracted from Notarchus leachii freeri eggs strings by the saltextractionmethod. The extraction conditions were optimized using the single-factorexperimentmethod and response surface method (RSM). The results showed that the maximum extraction yield of NLCEP was obtained under the following conditions: NaCl solution concentration of 2.96 %, raw material to liquid ratio of 1: 40 g/mL, extraction time of 2 h and extraction temperature of 69 °C. A new novel pure polysaccharide fraction named as NLCEPs-1 was fractionated from NLCEP by using DEAE-Cellulose 52 and Sephadex G-100. Its structure and immunomodulatory and antioxidant activities were analyzed. The results exhibited that the molecular weight of NLCEPs-1 was 31.4 kDa and it was composed of rhamnose, glucose, galactose, xylose and arabinose in the molar percentage of 11.128: 63.770: 5.439: 6.585: 13.077. The backbone of NLCEPs-1 was mainly consisted of â†’ )4-α-d-Glcp (1→, →6)-α-d-Glcp (1→, →1)-ß-d-Galp and ß-d-Galp-(1→. NLCEPs-1 exhibited the strong antioxidant activity in scavenging ability of various free radicals and immunomodulatory activity by the enhancement of the pinocytic capacity, nitric oxide (NO) and cytokines.

De novo transcriptome sequencing and analysis of the cuttlefish (Sepiella japonica) with different embryonic developmental stages.

In this study, embryos of Sepiella japonica from eye primordium formation to the larval growing stage were collected and used for RNA-Seq analysis. A total of 183,542,186 clean reads were assembled de novo into 58,054 unigenes consisting of 54,118,228 bp, with the average length at 932 bp and the N50 at 1667 bp. 21,469 (36.98%) unigenes were annotated at least in one of four databases including non-redundant protein (NR), Swiss-Prot, clusters of orthologous groups of proteins (KOG) and Kyoto Encyclopedia of Genes and Genomes (KEGG). 4460 (7.68%) unigenes were annotated in all databases. Analysis of differentially expressed genes (DEGs) was carried out on embryos at Eye primordium formation stage (SJ1), organ differentiation stage (SJ2), and hatching stage (SJ3). Overall, the current study provided the de novo assembly of S. japonica transcriptome and identified the DEGs and pathways during embryonic development, which will provide a fundamental genetic resource for further functional research.

Effects of chitin and sepia ink hybrid hemostatic sponge on the blood parameters of mice.

Chitin and sepia ink hybrid hemostatic sponge (CTSH sponge), a new biomedical material, was extensively studied for its beneficial biological properties of hemostasis and stimulation of healing. However, studies examining the safety of CTSH sponge in the blood system are lacking. This experiment aimed to examine whether CTSH sponge has negative effect on blood systems of mice, which were treated with a dosage of CTSH sponge (135 mg/kg) through a laparotomy. CTSH sponge was implanted into the abdominal subcutaneous and a laparotomy was used for blood sampling from abdominal aortic. Several kinds of blood parameters were detected at different time points, which were reflected by coagulation parameters including thrombin time (TT), prothrombin time (PT), activated partial thromboplatin time (APTT), fibrinogen (FIB) and platelet factor 4 (PF4); anticoagulation parameter including antithrombin III (AT-III); fibrinolytic parameters including plasminogen (PLG), fibrin degradation product (FDP) and D-dimer; hemorheology parameters including blood viscosity (BV) and plasma viscosity (PV). Results showed that CTSH sponge has no significant effect on the blood parameters of mice. The data suggested that CTSH sponge can be applied in the field of biomedical materials and has potential possibility to be developed into clinical drugs of hemostatic agents.

A comprehensive evaluation of the potential of semiterrestrial isopods, Ligia exotica, as a new animal food.

The semiterrestrial isopod, Ligia exotica represents one of the oldest documented species introductions of marine organisms and is known as an intermediate form between marine and strictly terrestrial isopods. In order to explore the potential value of Ligia as an animal food source, this study focused on the growth rate under laboratory rearing conditions and conducted a detailed analysis of the overall nutrient content of the species in comparison to two other marine food media (krill and fish meal). Evaluation of the growth rate of juveniles suggests it is a relatively fast-growing species of the Ligiidae family. The essential amino acids content Ligia meal is the lowest amongst the three studied media but the proportion of flavor amino acids, and in particular taurine, was higher. The most restricted amino acids of isopod meal are methionine and cysteine. The significantly unbalanced amino acid composition of Ligia meal may affect the absorption and utilization by consumers. In terms of fatty acids, the total polyunsaturated fatty acids in the isopod is very low. A total of 12 vitamins were examined. The VK1, VE, VB2, VB3, VB5 content of isopod meal were significantly higher than those of krill meal and fish meal. Similarly, most of the 11 mineral elements are highest in the isopod meal. Ligia therefore offers potential as an alternative natural food source in animal given the growth rate under culture and the overall nutrient content. But Ligia collected in most of the field would be deemed unfit for human consumption because of the relatively low nutritional value and heavy metal content exceeding the provided standard. Further study is warranted to elucidate the biological characteristics of isopods and how its diet is reflected in its nutritional value to consumers.

Astragaloside IV exerts angiogenesis and cardioprotection after myocardial infarction via regulating PTEN/PI3K/Akt signaling pathway.

AIMS AND METHODS: Acute myocardial infarction (AMI) is a common cardiovascular disease with high mortality. Astragaloside IV (AS-IV) was reported to have cardioprotective effect after AMI. We hypothesize that the cardioprotective role of AS-IV is exerted by enhancing angiogenesis via regulating PTEN/PI3K/Akt signaling pathway. To valid our hypothesis, AMI rats and human umbilical vein endothelial cells (HUVECs) were employed in our study. KEY FINDINGS: After treatment, cardiac function, survival rate, infarct size, pathological changes and fibrosis, cell apoptosis, ultrastructural changes, angiogenesis and expression of PTEN/PI3K/Akt signaling pathway were evaluated, respectively. In vitro study we detected proliferation, tube formation and signaling pathway activation of HUVECs treated with AS-IV, lentivirus overexpressed PTEN was employed to elucidate the potential mechanism. The results indicated that AS-IV administration significantly improved cardiac function and survival rate, limited infarct size, ameliorated pathological changes and fibrosis deposition, inhibited apoptosis, relieved ultrastructure injury and enhanced angiogenesis, PTEN/PI3K/Akt signaling pathway was activated simultaneously compared to the model group. In vitro study suggested that AS-IV treatment promoted cell proliferation and tube formation, and induced PTEN/PI3K/Akt signaling pathway activation. Importantly, overexpression of PTEN by lentivirus abolished AS-IV-induced angiogenesis. SIGNIFICANCE: Our study indicated that AS-IV could promote angiogenesis and cardioprotection after myocardial infarction. The mechanisms involve activation of PTEN/PI3K/Akt signaling pathway.

Effects of chitin and sepia ink hybrid sponge on the healing of burning wound rats and its impact on macrophages in vitro.

PURPOSE: To detect whether chitin and sepia ink sponge (CS) can promote wound healing and elevate impact of CS on phagocytosis ability of macrophages. METHODS: Forty-eight rats were assigned to four groups: Normal group (Normal), negative control group (Con), chitin and sepia ink sponge group (CS) and positive control Surgicel Gauze(r) group (SG). Deep second-degree burn model was created in rats. Wound area was recorded by digital imaging and determined using Image J software. Samples were collected and kept at -80oC on 3d, 7d, 14d and 21d for cytokines detecting. Transforming growth factor (TGF)-ß1, interleukin (IL)-6, matrix metalloproteinase (MMP)-1, hydroxyproline (Hyp) and macrophage activity reflected by tumor necrosis factor (TNF)-α were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Comparing to Con and SG, scabs in CS group fell off and basically healed on 21 day. TGF-ß1, IL-6, MMP-1 and Hyp were significantly increased by CS and SG comparing to Con (p < 0.05), CS had more apparently adjustment on TGF-ß1 and MMP-1 compared to SG; results in vitro indicated CS significantly promoted phagocytosis ability of macrophages reflected in TNF-α (p < 0.05). CONCLUSION: CS improved wound healing through exerting significant influences on secretion of kinds of cytokines and activating macrophages.

A transcriptome resource for pharaoh cuttlefish (Sepia pharaonis) after ink ejection by brief pressing.

Ink ejection is one of the most important defense mechanisms against external stimuli for pharaoh cuttlefish (Sepia pharaonis). The molecular changes during this process remain unknown. To understand the transcriptome changes after ink ejection by brief pressing, two cDNA libraries of pharaoh cuttlefish, from the inkjet group and control group were sequenced using Illumina HiSeq™ 2000. A total of 9,255,502,440nt bases were obtained and by de novo assembly, 73,298 unigenes were generated, which first provided numerous expressed sequence tags from pharaoh cuttlefish. By comparing the expression levels between the two groups, we identified 7064 up-regulated and 2024 down-regulated genes after ink ejection. These differentially-expressed genes included genes related to immunity, cancer, and blood coagulation, which indicated the various effects after ink ejection by brief pressing. These results provide new valuable resources for functional genomic and genetic studies on pharaoh cuttlefish.

Effects of chitin and sepia ink hybrid sponge on the healing of burning wound rats and its impact on macrophages in vitro

PURPOSE: To detect whether chitin and sepia ink sponge (CS) can promote wound healing and elevate impact of CS on phagocytosis ability of macrophages. METHODS: Forty-eight rats were assigned to four groups: Normal group (Normal), negative control group (Con), chitin and sepia ink sponge group (CS) and positive control Surgicel Gauze(r) group (SG). Deep second-degree burn model was created in rats. Wound area was recorded by digital imaging and determined using Image J software. Samples were collected and kept at -80oC on 3d, 7d, 14d and 21d for cytokines detecting. Transforming growth factor (TGF)-β1, interleukin (IL)-6, matrix metalloproteinase (MMP)-1, hydroxyproline (Hyp) and macrophage activity reflected by tumor necrosis factor (TNF)-α were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Comparing to Con and SG, scabs in CS group fell off and basically healed on 21 day. TGF-β1, IL-6, MMP-1 and Hyp were significantly increased by CS and SG comparing to Con (p < 0.05), CS had more apparently adjustment on TGF-β1 and MMP-1 compared to SG; results in vitro indicated CS significantly promoted phagocytosis ability of macrophages reflected in TNF-α (p < 0.05). CONCLUSION: CS improved wound healing through exerting significant influences on secretion of kinds of cytokines and activating macrophages.