Effect of freshwater discharge from Namgang Dam on ichthyoplankton assemblage structure in Jinju Bay, Korea

The movement of fish eggs and larvae in bay and estuarine systems is affected by freshwater discharge. In this study, the assemblage structures of ichthyoplankton eggs and larvae were assessed for the first time in Jinju Bay, South Korea, to identify the spawning and nursery functions of the bay. Fish eggs and larvae and several environmental parameters were sampled monthly from April 2015 to March 2016 inside and outside of the bay. Within the bay we collected eggs and larvae from 25 and 35 species, respectively, indicating greater diversity than outside the bay, where we collected eggs and larvae of 20 and 28 species, respectively. Fluctuations in water temperature and salinity were larger inside than outside of the bay, and chlorophyll-a concentration was higher within the bay, likely due to discharge from the Namgang Dam, which causes water to flow from the inside to the outside of the bay. This process influences fish larva abundance, such that more larvae are found outside than inside the bay. We also found that 28 fish species use Jinju Bay as a spawning ground. For some species, the timing of egg and larva appearance differed inside and outside of the bay, suggesting that the timing of spawning may differ between the two environments

Mechanism and treatment for learning and memory deficits in mouse models of Noonan syndrome.

In Noonan syndrome (NS) 30-50% of subjects show cognitive deficits of unknown etiology and with no known treatment. Here, we report that knock-in mice expressing either of two NS-associated mutations in Ptpn11, which encodes the nonreceptor protein tyrosine phosphatase Shp2, show hippocampal-dependent impairments in spatial learning and deficits in hippocampal long-term potentiation (LTP). In addition, viral overexpression of an NS-associated allele PTPN11(D61G) in adult mouse hippocampus results in increased baseline excitatory synaptic function and deficits in LTP and spatial learning, which can be reversed by a mitogen-activated protein kinase kinase (MEK) inhibitor. Furthermore, brief treatment with lovastatin reduces activation of the GTPase Ras-extracellular signal-related kinase (Erk) pathway in the brain and normalizes deficits in LTP and learning in adult Ptpn11(D61G/+) mice. Our results demonstrate that increased basal Erk activity and corresponding baseline increases in excitatory synaptic function are responsible for the LTP impairments and, consequently, the learning deficits in mouse models of NS. These data also suggest that lovastatin or MEK inhibitors may be useful for treating the cognitive deficits in NS

Gold Nanoparticle-Enhanced and Roll-to-Roll Nanoimprinted LSPR Platform for Detecting Interleukin-10

Localized surface plasmon resonance (LSPR) is a powerful platform for detecting biomolecules including proteins, nucleotides, and vesicles. Here, we report a colloidal gold (Au) nanoparticle-based assay that enhances the LSPR signal of nanoimprinted Au strips. The binding of the colloidal Au nanoparticle on the Au strip causes a red-shift of the LSPR extinction peak, enabling the detection of interleukin-10 (IL-10) cytokine. For LSPR sensor fabrication, we employed a roll-to-roll nanoimprinting process to create nanograting structures on polyethylene terephthalate (PET) film. By the angled deposition of Au on the PET film, we demonstrated a double-bent Au structure with a strong LSPR extinction peak at ~760 nm. Using the Au LSPR sensor, we developed an enzyme-linked immunosorbent assay (ELISA) protocol by forming a sandwich structure of IL-10 capture antibody/IL-10/IL-10 detection antibody. To enhance the LSPR signal, we introduced colloidal Au nanocube (AuNC) to be cross-linked with IL-10 detection antibody for immunogold assay. Using IL-10 as a model protein, we successfully achieved nanomolar sensitivity. We confirmed that the shift of the extinction peak was improved by 450% due to plasmon coupling between AuNC and Au strip. We expect that the AuNC-assisted LSPR sensor platform can be utilized as a diagnostic tool by providing convenient and fast detection of the LSPR signal. © Copyright © 2020 Baek, Song, Lee, Kim, Kim, Wi, Ok, Park, Hong, Kwak, Lee and Nam.1

Composition and abundance of Benthic Macrofauna of a tropical sea-grass bed in North Queensland, Australia

The aims of this study were to characterize the functional composition of benthic macrofauna of a tropical sea-grass bed and to determine temporal variations in abundance of benthic macrofauna in relation to environmental factors such as sea-grass biomass, temperature, salinity, and sediment type. Benthic macrofaunal composition and abundance were investigated by core sampler during April 1999, October 1999, March 2000, and August 2000 at three stations within a sea-grass bed at Cockle Bay in North Queensland, Australia. A total of 110 species of benthic macrofauna was collected. Polychaetes were the most abundant group (37 species; 52% of total macrofaunal numbers; 47% of biomass) followed by amphipods (27 species; 35% of total numbers). Decapods were also important, with 28 species contributing 31% of total macrofaunal biomass. Other miscellaneous groups were tanaids, isopods, and ophiuroids. Most amphipods (65%) and decapods (90%) were epifaunal, but polychaetes were equally represented by epifauna and infauna. Temporal variation in both species composition and abundance was large: the peak number of benthic macrofauna occurred in April 1999 and March 2000, and biomass was highest in April 1999. Benthic macrofauna numbers as well as biomass were lowest in August 2000. These temporal patterns of abundance of benthic macrofauna appeared to correlate closely with temporal variation of sea-grass biomass. In addition, the factors of life cycle and predation by common fish species may be indirectly associated with these patterns of macrofaunal abundance

Crustacean Decapod Assemblage Associated with Seagrass (Zostera marina) Beds in Southern Waters of Korea

Decapod assemblages in Zostera marina beds from two bays adjacent to unvegetated habitats were investigated to assess their influence on decapod assemblages. Thirty-eight decapod species belonging to four taxa were collected using a small beam trawl at four habitat types from two different locations off the coast of Namhae Island, South Korea. Dominant decapod taxon at all habitats was the caridean shrimps, with Eualus leptognathus, Heptacarpus pandaloides, Latreutes anoplonyx, La. Laminirostris, and Palaemon macrodactylus being the most abundant caridean species. Crabs were characterized with the highest biomass, but with moderate species richness and abundance. Penaeoid and sergestoid shrimps only accounted for <1% of the total decapod abundance. The number of species and their abundance of decapod assemblages varied greatly by habitat type, season, and diel patterns, but not diversity. Species number and abundance peaked in seagrass beds of southern exposed bays during the autumn and were lowest in unvegetated habitats during the summer months. Diel decapod catch rates were higher at night. Dense seagrass vegetation and nighttime supported higher decapod mean densities, but not species richness and diversity. Multivariate analyses revealed that habitat type and season significantly affected the structure of decapod assemblages, but diel patterns had a minor influence. Among decapod species, Pa. macrodactylus and Pugettia quadridens characterized the decapod assemblages in seagrass beds at the northern semi-closed bay, while Telmessus acutidens, Crangon affinis, Cr. hakodatei, Charybdis (Charybdis) japonica, and Portunus sanguinolentus were significantly associated with both vegetated and unvegetated habitats at the southern exposed bay, with the former two species more abundant during the colder season

Effect of freshwater discharge from Namgang Dam on ichthyoplankton assemblage structure in Jinju Bay, Korea

The movement of fish eggs and larvae in bay and estuarine systems is affected by freshwater discharge. In this study, the assemblage structures of ichthyoplankton eggs and larvae were assessed for the first time in Jinju Bay, South Korea, to identify the spawning and nursery functions of the bay. Fish eggs and larvae and several environmental parameters were sampled monthly from April 2015 to March 2016 inside and outside of the bay. Within the bay we collected eggs and larvae from 25 and 35 species, respectively, indicating greater diversity than outside the bay, where we collected eggs and larvae of 20 and 28 species, respectively. Fluctuations in water temperature and salinity were larger inside than outside of the bay, and chlorophyll-a concentration was higher within the bay, likely due to discharge from the Namgang Dam, which causes water to flow from the inside to the outside of the bay. This process influences fish larva abundance, such that more larvae are found outside than inside the bay. We also found that 28 fish species use Jinju Bay as a spawning ground. For some species, the timing of egg and larva appearance differed inside and outside of the bay, suggesting that the timing of spawning may differ between the two environments

First Report of the Dinoflagellate Genus Effrenium in the East Sea of Korea: Morphological, Genetic, and Fatty Acid Characteristics

Most species in the family Symbiodiniaceae are symbiotic partners to invertebrate and protist hosts, but a few live freely in water columns. Here, a free-living dinoflagellate was isolated from the waters off the Dokdo Islands in the East Sea of Korea. Morphological and molecular analyses show this isolate belongs to Effrenium voratum. Prior to the present study, E. voratum had been reported to live in the waters in the temperate latitudes in the western North Pacific, the southwest Western Pacific, the eastern North Pacific, the eastern Atlantic, and the Mediterranean Sea. To our knowledge, this is the highest latitude in the western North Pacific, where E. voratum has been reported. This report extends the known range of this dinoflagellate to the temperate waters of the western North Pacific Ocean. The sequence of the D1/D2 region of the large subunit ribosomal DNA (LSU rDNA) was identical to E. voratum found in Jeju Island, Korea, Tsushima Island, Japan, and Cook Strait, New Zealand, suggesting this species is cosmopolitan. However, it was different by 1 bp from those found in Blanes, Spain and Santa Barbara, USA. In the phylogenetic tree built on the basis of the LSU (D1-D2) rDNA region sequences, this dinoflagellate was clustered within a clade, including all the other E. voratum strains. Morphological characteristics were like those of strains found in the waters of Jeju Island. This is the first report conducted on the fatty acid profile of fully characterized E. voratum. Importantly, the isolate possessed a high ratio of long-chain omega-3 polyunsaturated fatty acids (PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) relative to total lipid. This dinoflagellate could be a candidate for commercial applications, such as aquaculture feed and essential omega-3 PUFA productions

Characterization of Korean Red Ginseng (Panax ginseng Meyer): History, preparation method, and chemical composition

AbstractIt has been reported that Korean Red Ginseng has been manufactured for 1,123 y as described in the GoRyeoDoGyeong record. The Korean Red Ginseng manufactured by the traditional preparation method has its own chemical component characteristics. The ginsenoside content of the red ginseng is shown as Rg1: 3.3 mg/g, Re: 2.0 mg/g, Rb1: 5.8 mg/g, Rc:1.7 mg/g, Rb2: 2.3 mg/g, and Rd: 0.4 mg/g, respectively. It is known that Korean ginseng generally consists of the main root and the lateral or fine roots at a ratio of about 75:25. Therefore, the red ginseng extract is prepared by using this same ratio of the main root and lateral or fine roots and processed by the historical traditional medicine prescription. The red ginseng extract is prepared through a water extraction (90°C for 14–16 h) and concentration process (until its final concentration is 70–73 Brix at 50–60°C). The ginsenoside contents of the red ginseng extract are shown as Rg1: 1.3 mg/g, Re: 1.3 mg/g, Rb1: 6.4 mg/g, Rc:2.5 mg/g, Rb2: 2.3 mg/g, and Rd: 0.9 mg/g, respectively. Arginine-fructose-glucose (AFG) is a specific amino-sugar that can be produced by chemical reaction of the process when the fresh ginseng is converted to red ginseng. The content of AFG is 1.0–1.5% in red ginseng. Acidic polysaccharide, which has been known as an immune activator, is at levels of 4.5–7.5% in red ginseng. Therefore, we recommended that the chemical profiles of Korean Red Ginseng made through the defined traditional method should be well preserved and it has had its own chemical characteristics since its traditional development