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Abstract: The potential effects of three heavy metals (Cu, Pb, and Cd) on hatching success of Acartia pacifica resting eggs in the sediment of Xiamen Bay were experimentally investigated. The number of A. pacifica nauplii hatched from the sediment sharply decreased with the increase of metal concentration and exposure time from 3 to 30 d. An increase of the Cu concentration from 34.8 to 348 mg/kg, reduced the number of hatched nauplii by 46.6%–100%. An increase of the Pb concentration from 75.2 to 752 mg/kg, reduced the number of hatched nauplii by 21.4%–78.9%. An increase of the Cd concentration from 0.68 to 6.8 mg/kg, reduced the number of hatched nauplii by 31.6%–94.7%. The number of nauplii also significantly decreased with the increase of mixed-metal concentration and exposure time in the mixed-metal test. Trimmed Spearman-Karber analysis gave sediment metal 72-h LC50 values of 1.25 mmol Cu/kg, 1.73 mmol Pb/kg, and 0.054 mmol Cd/kg, which suggested that Cd was the most toxic to A. pacifica resting eggs in the three tested metals. The results indicate that heavy metals with higher concentrations can reduce recruitment of A. pacifica nauplii from benthic resting eggs to planktonic population. [Copyright &y& Elsevier]

• Mechanical stress stimuli response release drug. • Effective targeting of inflammatory macrophages at plaque. • Dual sensitive hydrogel with simvastatin. • Novel double-response hydrogel drug carrier for atherosclerosis treatment. Atherosclerotic lesions create obvious vascular stenosis due to the presence of plaque, and a large number of inflammatory macrophages are enriched in the thrombus. In this study, we develop a composite hydrogel drug delivery system that is capable of both mechanically-sensitive drug release and of targeting inflammatory macrophages at the thrombus. The hydrogel is a high molecular weight hyaluronic acid (HA) modified with glycidyl methacrylate as a hydrogel precursor; a cross-linkable block copolymer (CBC) is used as the drug coating material and a microscopic cross-linking agent. The difference in drug release rate of the composite hydrogel (HACBC) in simulated blood vessels with 0 % and 75 % occlusion was as high as 49.3 %. Under long-term cycling conditions in stenotic vessels, dynamic shear rheometry revealed that the HACBC still maintained the hydrogel properties. However, the micelles were deformed and recombined to produce smaller sized micelles. An in vitro cell culture demonstrated precise targeting of the HACBC to inflammatory macrophages, and our rabbit experiments with simvastatin-coated HACBC confirmed the effective release of simvastatin in the plaque of the drug carrier. Moreover, we demonstrated the precise targeting of HACBC in vivo in apoE-/- mice by using HACBC coated with cy7. The mechanical stress-sensitive and CD44 receptor-targeted dual-response drug delivery system prepared by micellar composite hydrogel is the first application in the field of atherosclerosis, which provides a new method for diagnosing and treating atherosclerosis. [ABSTRACT FROM AUTHOR]

Abstract: To better understand the underlying mechanisms of reactions of copepods exposed to elevated level of nickel, the suppression subtractive hybridization (SSH) was used to elucidate the response of the copepod Pseudodiaptomus annandalei to nickel exposure at the gene level. P. annandale is one of a few copepod species that can be cultured relatively easy under laboratory condition, and it is considered to be a potential model species for toxicity study. In the present study, P. annandalei were exposed to nickel at a concentration of 8.86mgL−1 for 24h, after which the RNA was prepared for SSH using unexposed P. annandalei as drivers. A total of 474 clones on the middle scale in the SSH library were sequenced. Among these genes, 129 potential functional genes were recognized based on the BLAST searches in NCBI and Uniprot databases. These genes were then categorized into nine groups in association with different biological processes using AmiGO against the Gene Ontology database. Of the 129 genes, 127 translatable DNA sequences were predicted to be proteins, and the putative amino acid sequences were searched for conserved domains (CD) and proteins using the CD-Search service and BLASTp. Among 129 genes, 119 (92.2%) were annotated to be involved in different biological processes, while 10 genes (7.8%) were classified as an unknown-function gene group. To further confirm the up-regulation of differentially expressed genes, the quantitative real time PCR were performed to test eight randomly selected genes, in which five of them, i.e. α-tubulin, ribosomal protein L13, ferritin, separase and Myohemerythrin-1, exhibited clear up-regulation after nickel exposure. In addition, MnSOD was further studied for the differential expression pattern after nickel exposure and the results showed that MnSOD had a time- and dose-dependent expression pattern in the copepod after nickel exposure. To the best of our knowledge, this is the first attempt to investigate the toxicity effects of nickel on a copepod at molecular level. [Copyright &y& Elsevier]

Abstract: The species composition and distribution of planktonic copepods in relation to hydrographical characteristics in the southern Taiwan Strait were investigated during the summers of 1988, 1994, 2005 and 2006. Two station groups (I and II) and two copepod assemblages (nearshore and offshore) based on sea surface temperature, salinity, chlorophyll a and copepod abundance were revealed through cluster and detrended correspondence analysis. Station-group I was found in nearshore regions including the upwelling areas, and primarily consisted of coastal/neritic species; while station-group II was found in offshore regions and primarily consisted of oceanic species. Indicator analysis identified the coastal/neritic species Temora turbinata and Acrocalanus gibber are good indicators of the nearshore assemblage. The oceanic species Paraeuchaeta russelli and 6 additional species are indicators of the offshore assemblage. The results showed that Acartia pacifica is an indicator species of coastal waters with freshwater runoff, and Calanus sinicus is an indicator species of hypothermic upwelled waters in the southern Taiwan Strait during summer. [Copyright &y& Elsevier]

Abstract: Juvenile crabs are small, frail and frequently molt, which poses a great challenge to individual identification. This study evaluated the use of single and double visible implant elastomer marks in juvenile mud crabs Scylla paramamosain (1.57–2.50cm carapace width). Elastomer was injected ventrally in body sites adjacent to the second, third and fourth pair of pereiopods. After eight weeks, the untagged, single-tagged and double-tagged treatments showed no differences in survival, development or growth. For the three treatments, there were also no differences in the amylase, trypsinase and SOD (superoxide dismutase) activities in the hepatopancreas. However, the lactate dehydrogenase, adenosine triphosphatase and SOD levels in crab muscle where elastomer was implanted were higher than respective muscle in untagged crabs. Although most crabs had gone through three ecdyses, all surviving crabs in the tag treatments retained visible elastomer material. Except for elastomer implanted ventrally adjacent to the fourth, left pereiopod, elastomer at the other five sites were mostly clear and intact during cultivation with no difference between single-tagged and double-tagged treatments. Finally, dissection revealed that tags mainly migrated to the surface of the gill with the degree of tag migration dependent on the depth of injection. [Copyright &y& Elsevier]

Abstract: The mud crab Scylla serrata is an important commercial crustacean inhabiting estuarine water along the coast of southeast China. Metabolism in the gill is affected continuously by fluctuating water temperature and, therefore, the ability to cope with temperature change is essential to maintain physiological function. This experiment was conducted to help understand the mechanism of low temperature adaptation in S. serrata gill. In this study, 40 healthy juvenile male S. serrata from the same broodstock were grouped randomly into four groups, which were kept at 5 °C, 10 °C, 15 °C and 27 °C, with the same feeding regime during a 3-week adaptation period. Two-dimensional electrophoresis of the proteome was conducted to separate the specific proteins responsible for low temperature adaptation. Variations in the mitochondria were observed using transmission electron microscopy, and fatty acid composition was determined using gas chromatography. The results showed that different numbers of specific proteins were expressed under different low temperature adaptation, with more expressed at 5 °C and 10 °C than at 15 °C. Mitochondrial morphology also varied under different low temperature adaptation, but there was no linear relationship between microbial density and adaptation temperature. The composition of different fatty acids in the gill varied considerably with adaptation temperature, but elongation of the carbon chain and transition from fatty acids occurred at lower temperatures. Thus, changes in the specific proteins, mitochondria and fatty acid composition of the gill were the positive effects of low temperature on metabolism, leading to improved adaptation ability in S. serrata. [Copyright &y& Elsevier]

Abstract: Scygonadin is a novel antimicrobial peptide, which was originally isolated from the seminal plasma of the mud crab, Scylla serrata. Based on the partial 20-residue NH2-terminal sequence of the peptide, H-Gly-Gln-Ala-Leu-Asn-Lys-Leu-Met-Pro-Lys-Ile-Val-Ser-Ala-Ile-Ile-Tyr-Met-Val-Gly-OH, scygonadin was cloned from the gonads of S. serrata using a degenerated reverse transcriptase (RT)-PCR and rapid amplification of cDNA ends (RACE). The full-length cDNA sequence contains an open reading frame of 539 bases (excluding polyA) with a coding capacity of 126 amino acids, which constitutes a putative NH2-terminal signal sequence (1–24) and a mature peptide (25–126). Analysis of the genomic DNA sequence revealed that scygonadin consists of 2300bp containing two introns (1569 and 120bp) and three exons (187, 131 and 218bp) and this sequence is different from any other reported antimicrobial peptide. The theoretical pI of the mature peptide is 6.09, which suggests that it is an anionic molecule. The sex and tissue-specific expression of the scygonadin gene was revealed using RT-PCR and Northern-blot analysis of multiple tissues of S. serrata males and females and this demonstrated that the scygonadin gene was predominantly expressed in the male reproductive tract of S. serrata and was restricted to the ejaculatory duct. This suggests that scygonadin might be one of the antibacterial peptides responsible for protection of the male crab reproductive tract from invading pathogenic microorganisms, so as to maintain a sterile environment leading to successful fertilization. [Copyright &y& Elsevier]

Abstract: A novel protein was isolated from the seminal plasma of the mud crab, Scylla serrata (Forskål, 1775). It exhibited an antibacterial activity against the Gram-positive bacterium Micrococcus leteus with IC90 of 0.125 mg/ml. The extraction procedure for the protein included techniques of acid extraction, ion-exchange chromatography on SP-Sepharose Fast Flow and reverse-phase liquid chromatography on Source 5R RPC. It showed a molecular mass of 10.8 kDa by SDS-PAGE. A partial 20 residue NH2-terminal sequence was determined by Edman degradation and MS-fingerprint of the protein was conducted. Similarity search in protein databases (BLAST) revealed that the protein exhibited no significant homology to any other reported antimicrobial peptides. We propose the name Scygonadin (from the gonad of S. serrata) for this antibacterial protein. [Copyright &y& Elsevier]