Two newly recorded sea stars, Henricia densispina (Sladen, 1879) and H. reniossa asiatica Djakonov, 1958, collected from the East Sea of Korea using fishing nets, were described in this study. Morphologically, H. densispina is characterized by the shape (sub-triangular) similarity of the intermarginal plates to the superomarginal plates. Henricia reniossa asiatica Djakonov, 1958, has long and slender arms (R/r=7.2- 9.1); clustered abactinal paxillae with 3-13 abactinal spinelets; a denuded abactinal skeleton made up of crescentic, elongated cross-shaped, the presence of small ossicles that divided the papular areas; and an adambulacral armature comprised of 14-17 spinelets. This study provides the first occurrence of H. densispina and H. reniossa asiatica in the Korean fauna and a detailed morphological description of these species’ key characteristics is provided.
In this study, the community structure of marine benthic invertebrates was examined to evaluate the differences between the west, south, and east coasts of Korea and to identify the indicator species representing each region. Acrylic attachment plate sets were installed in Jeongok, Mokpo, Tongyeong, Yangpo, and Gangreung, and the invertebrate fauna thus captured were identified. Monitoring was performed in each area from March 2017 to May 2018. Water depth, temperature, and salinity at each location were measured to determine the potential influence of abiotic factors on the community structure. As a result, the mean depth of plates installed and the water temperature were significantly different in each area. A total of 32 invertebrate species were identified in all localities, and the most significant difference in the species compositions was found between Mokpo and Gangreung. The community structure differed significantly with a change in the plate depth, and a larger number of indicator species appeared on shallower plates. Finally, we determined the community structure of benthic invertebrates in different geographical regions of the Korean ocean by characterizing the dominant invertebrate taxa and the indicator species at each site.
Henricia specimen was collected from the East Sea of Korea using fishing nets. The specimen was identified as Henricia hayashii (Djakonov 1961), belonging to the family Echinasteridae of the order Spinulosida. This species can be distinguished from other Henricia species by slender arms (R/r=7.4), constricted arm base, six to thirtyfive slender spinelets, open-meshed, reticulated abactinal skeleton comprising semitriangular, rod-like form, and small ossicles present inside the papular areas. This species superficially resembles H. reniossa in terms of its body size but differs in the shape and arrangement of the abactinal and actinal plates. To date, two genera of Echinasteridae, Aleutihenricia and Henricia, including a total of 14 species, have been reported in Korea. Herein, the morphological characteristics of H. hayashii are described, and photographs are provided.
Resistance to extended-spectrum cephalosporin in Enterobacteriaceae is increasingly prevalent in South Korea. This study aims to explore the distribution of AmpC genes in Proteus mirabilis isolated from stray and hospital-admitted companion animals in South Korea. AmpC β-lactamases hold clinical significance due to its potential to facilitate antimicrobial resistance to cefoxitin, cefazolin, and most penicillins. A total of 163 bacterial isolates belonging to the Enterobacteriaceae family were collected from dogs (n = 158) and cats (n=5). Of them, 134 isolates were from hospital-admitted animals, while 29 isolates from stray animals. Boronic acid tests and antimicrobial susceptibility tests were conducted for an initial screening to detect AmpC β-lactamase resistant P. mirabilis. Gene-specific PCRs were conducted to identify the type of AmpC genes, which include six groups (MOXM, CITM, DHAM, ACCM, EBCM, and FOXM), in the resistant isolates. The boronic acid disk tests revealed 45 (27.6%) positive isolates out of 163 isolates tested. Of these 45 isolates, six were determined to harbor the EBCM gene, 13 for CITM, one for FOXM, and one for DHAM by single detection PCR. No isolates carried for ACCM or MOXM. Thus, a total of 21 out of 163 isolates (12.9%) were demonstrated to possess AmpC genes. No isolates contain more than one group of AmpC gene family. A significantly higher percentage of P. mirabilis was found to possess AmpC genes compared to past studies. Therefore, the increasing trend in antimicrobial resistance in P. mirabilis indicates a dire need to monitor antimicrobial prescription in the veterinary field.
The effects of temperature and salinity on egg development and settlement of the ascidian Herdmania momus were investigated. Adult specimens were collected from the Dodu Yacht facility in Jeju Island, Korea (33°30′30.54″N, 126°27′55.46″E) in August 2018. Egg development and larval settlement were observed and recorded at 8 h intervals using a stereomicroscope, under nine temperature (10, 13, 16, 19, 22, 25, 28, 31, and 34°C), and four salinity regimens (28, 30, 32, and 34 psu). The highest hatching rate (82.8±7%) was observed at 32 psu and 25°C and the lowest hatching rate (1.0±2%) was at 34 psu and 13°C. The developmental rate (0.222±0.0994) was highest at 28 psu and 28°C, and lowest (0.016±0.008) at 30 psu and 13°C. The highest settlement success rate (77.1±5%) was at 32 psu and 25°C and the lowest (0.1±1.0%) was at 30 psu, and 13°C. The rate of settlement (0.080±0.000) was highest at 28 psu and 28°C, and lowest (0.013±0.000) at 30 psu and 13°C. Both hatching and settlement success rates increased as temperature increased and tended to decrease beyond an optimal temperature range. Herdmania momus preferred 30-34 psu salinity and 22-25°C temperature. This study provides baseline information about the life history of H. momus, and important data to control the damage caused by the increase in number and distribution of this invasive ascidian.
Henricia specimens were collected using fishing nets from the East Sea of Korea. The specimens were identified as Henricia oculata Pennant, 1777, belonging to the family Echinasteridae of the order Spinulosida. This species can be distinguished from other Henricia species by broad arms (R/r=4-4.1), rough skin, a thick arm base, three to nine minute delicate abactinal spines, and inferomarginal plates reniform in shape. This species superficially resembles H. pachyderma in its body size and wide papular areas but differs mainly in the number of papulae and abactinal spines, and the shape and arrangement of the inferomarginal plates. To date, two genera of Echinasteridae, Aleutihenricia and Henricia, with a total of 13 species, have been reported in Korea. The morphological characteristics of H. oculata are described, and photographs are provided.
Sea stars were collected from the adjacent waters of Jukbyeon and Jumunjin, Korea, using fishing nets at depths of 70-100 m. The specimens were identified as Henricia perforata (O.F. Müller, 1776) in the family Echinasteridae and order Spinulosida, with worldwide species distribution. H. perforata can be distinguished from some morphologically related Henricia species by its long, slender, and pointed adambulacral spines. The abactinal skeleton of H. perforata has wide papular areas resembling those of H. pachyderma, but the former has more papulae (two to seven). Previously, two genera of Echinasteridae, Aleutihenricia and Henricia, with a total of 12 echinasterid species, have been reported in Korea. The morphological characteristics of H. perforata are described and photographs are provided.
The influx of marine exotic and alien species is disrupting marine ecosystems and aquaculture. Herdmania momus, reported as an invasive species, is distributed all along the coast of Jeju Island and has been confirmed to be distributed and spread to Busan. The potential habitats and distribution of H. momus were estimated using the maximum entropy (MaxEnt) model, quantum geographic information system (QGIS), and Bio-ocean rasters for analysis of climate and environment (Bio-ORACLE), which can predict the distribution and spread based only on species occurrence data using species distribution model (SDM). Temperature and salinity were selected as environmental variables based on previous literature. Additionally, two different representative concentration pathway (RCP) scenarios (RCP 4.5 and RCP 8.5) were set up to estimate future and potential habitats owing to climate change. The prediction of potential habitats and distribution for H. momus using MaxEnt confirmed maximum temperature as the highest contributor (77.1%), and mean salinity, the lowest (0%). And the potential habitats and distribution of H. momus were the highest on Jeju Island, and no potential habitat or distribution was seen in the Yellow Sea. Different RCP scenarios showed that at RCP 4.5, H. momus would be distributed along the coast of Jeju Island in the year 2050 and that the distribution would expand to parts of the Korea Strait by the year 2100. RCP 8.5, the distribution in 2050 is predicted to be similar to that at RCP 4.5; however, by 2100, the distribution is predicted to expand to parts of the Korea Strait and the East Sea. This study can be utilized as basic data to effectively control the ecological injuries by H. momus by predicting its spread and distribution both at present and in the future.
Asteroid specimens were collected using fishing nets from the East Sea, Korea. The specimens were identified as Solaster paxillatus Sladen, 1889, belonging to the family Solasteridae of the order Valvatida. This species can be distinguished from three other Korean Solaster species by having 10 arms; subambulacral spines comprising four or five near base of arm, six or seven in middle part, and five or six in distal part of arm; furrow spines comprising four or five near basal part and three or four in distal part of arm; and suboral spines comprising more than ten spinules. The morphological characteristics of this species were described with illustrations. Solaster paxillatus is first reported in marine fauna of Korea.
An asteroid specimen that belongs to the genus Henricia was collected from the waters near Ongpo harbor, Jeju Island using fishing net on 24 January 2017. The specimen was identified as Henricia anomala Hayashi, 1973, which belongs to the family Echinasteridae and order Spinulosida. Henricia anomala was first described by Hayashi, 1973, who captured it from Sagami Bay at a depth of 110-116 m. This species can be distinguished from other Henricia species by short arms (R/r=4), abactinal spines lining the abactinal plates and bearing about two to five spinelets, closely meshed abactinal skeleton, composed of small rod-like and subtriangular plates, a narrow papular area containing one or two papulae, and adambulacral armature composed of five to seven bluntly pointed spinelets. This is the first report of Henricia anomala in Korea.
The active development of the global marine trade industries has been known to increase the inflows of marine invasive species and harmful organisms into the ecosystem, and the marine ecological disturbances. One of these invasive species, Ciona robusta, has now spread to the Korea Strait, the East Sea, and Jeju Island in connection with the climate change but not the Yellow Sea in Korea. Currently, the spread and distribution of C. robusta is increasingly damaging aquaculture and related facilities. Therefore, this study aims to identify the spread of C. robusta and potential habitats and to secure a data for the prevention of effective management measures due to climate change as well as damage the reduction in future through the prediction of spread. We used environmental variables in BioOracle. Also, the potential habitat and distribution of C. robusta was predicted using MaxEnt, a species distribution model. Two different RCP scenarios (4.5 and 8.5) were specified to predict the future distributions of C. robusta. The results showed that the biggest environmental factor affecting the distribution of C. robusta was the salinity as well as
The purpose of the study was to investigate the immediate effects of negative pressure soft tissue therapy on muscle tone, muscle stiffness and balance in patients with stroke. In total, 20 patients with stroke and assigned to the negative pressure soft tissue therapy group (NPST, n=10) or, placebo-negative pressure soft tissue therapy group(Placebo-NPST, n=10). Both groups underwent NPST or placebo-NPST once a day during the experimental period. MyotonPRO was used to assess the parameters for muscle tone and stiffness. Biorescue was used to assess the parameters for balance. Each group showed improvements in muscle tone, muscle stiffness, and balance ability (p<.05). Especially, Muscle tone, muscle stiffness, and anterior length in the limit of stability were the significant improvement on NPST group (p<.05). The results of the study suggest that the NPST is effective in improving muscle tone, muscle stiffness, and balance ability in patients with stroke.
본 연구는 거친대추멍게 (Ascidiella aspersa)의 알 발육과 유생 부착에 미치는 수온과 염도의 영향을 파악하고자 실시하였다. 거친대추멍게 알 발육과 유생 부착 실험은 12개의 수온 조건 (6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28°C, 과 2개의 염도 조건 (30, 34 psu)에서 진행하였다. 거친대추멍게 알의 부화율과 발육률은 염도에 관계없이 수온이 높아짐에 따라 증가하는 경향을 보였으며 최적 수온 범위 이후 감소하는 경향을 보였으며 부화 및 발육을 위한 최적 수온은 20~22°C의 범위를 보였다. 저온 발육임계수온은 30 psu와 34 psu에서 각각 1.5°C와 1.8°C로 큰 차이를 보이지 않았다. 부착률은 염도에 관계없이 16~22°C의 최적 수온 범위를 보였으며 부착시간은 수온이 증가함에 따라 지속적으로 증가 하였다. 결과적으로 거친대추멍게의 최적 발육 및 생존 수온은 염도 조건에 관계없이 20~22°C 범위를 보였다. 본 연구 결과는 국내 양식장에서의 거친대추멍게에 의한 경제적 피해가 증가하고 있는 시점에서 거친대추멍게의 분포 및 발생 시기를 예측하고 확산 방지 및 방제 방안을 구축하는 데 활용될 수 있을 것으로 생각된다.
The Korean aquaculture industry was generally began in the 1970s and has gradually increased. Now, the number of households is about 7,068 and the scale of an aquaculture farm is about 248,014 ha; the value of all production in the industry is estimated to be about 1602.2 billion won. The aquaculture industry is very valuable and important for future food resources. However, the aquaculture industry was damaged by several marine ecological disturbance causing organisms. The Ascdiella aspersa colonized on the shell of scallop and then scallops were detached from rope. The patterns of damage in the aquacultures were observed in Tongyeong (oyster), Geojedo (oyster), and Gangneung (sea squirt) in June, 2017, as well as in Tongyeong (oyster) in November, 2017 by SCUBA divers. The species Halichondria bowerbanki, Bugula neritina, Mytilus galloprovincialis, Balanus amphitrite, Ascidiella aspersa, Ciona intestinalis, Didemnum sp, Styela plicata in Tongyeong, M. galloprovincialis, A. aspersa, C. intestinalis, D. vexillum, S. plicata in Geojedo, and M. galloprovincialis in Gangneung were all usually found in their farms. The marine ecological disturbance causing organisms gave rise to a reduced number of aquaculture products.
Asteroid specimens of the genus Diplopteraster were collected by trawling nets at a depth of 93 m on 05 November 2016 from the Korea Strait (33°41′N, 127°26′E). The specimens were identified as Diplopteraster multipes (M. Sars, 1866), which belongs to the family Pterasteridae, order Velatida. This species is similar to other Diplopteraster species in its pentagonal stellate shape, but is distinguished by having each paxilla composed of a protruded spine, more than eight spiracles, and regularly reticulated muscular bands. It is not commonly found in shallow water. This is the first report of the genus Diplopteraster and D. multipes in Korea.
A native species to the European ocean, the tunicate Ciona intestinalis now appears worldwide, from sub-Arctic to tropical regions. C. intestinalis generally occurs as an opportunistic fouling organism on artificial substrates in harbors or aquaculture. This study focused on estimating the early growth pattern of C. intestinalis under various temperature conditions. Adults were collected from the Guryungpo harbour in November 2017, and their artificially inseminated eggs were used for the study. The growth of the C. intestinalis was investigated at 8 constant temperatures, ranging from 12°C to 26°C, at 30 psu. Results indicate that the growth of C. intestinalis increased with increasing temperature. The growth was sluggish at 12°C, and decreased at 26°C. The optimal temperature for growth of C. intestinalis was therefore estimated to be between 20°C and 24°C.
Aneurysmal bone cyst (ABC) in maxilla is a rare and benign lesion but shows extensive bony destruction, occasionally accompanied with secondary osseous lesions, i.e., central giant cell granuloma, ossifying fibroma, fibrous dysplasia, etc. As the pathogenesis of ABC has not been clearly defined, ABC is diagnostically challenged due to its variable histological features. A 17-year-old boy showed a huge radiolucent lesion at right anterior maxilla, which was accidentally found in routine dental-radiological examination for orthodontic treatment. He had no medical history of systemic disease, and did not remember any traumatic experience on his right anterior maxilla. The radiolucent lesion involved periapical area from right central incisor to right first premolar, and was clinically diagnosed as odontogenic keratocyst. During surgical operation a cyst-like sac was enucleated with severe hemorrhage. In the histological observation the thick fibrous sac showed no lining epithelium, and its luminal side disclosed multiple aneurysmal spaces which were shrunken and almost obliterated. The fibrous sac itself was hyperplastic with abundant vascular channels, and produced fibromatous thickening associated with ossifying trabecular bones. This fibro-osseous tissue was hamartomatous, which was not directly connected and organized with marrow bone of maxilla. Finally, the present case was diagnosed as secondary type ABC differentially from traumatic bone cyst (TBC), odontogenic cyst, and central reparative granuloma. And it was presumed that the hamartomatous proliferation of fibro-osseous tissue in the cystic sac of ABC could produce the swelling pressure effect in the bone marrow similar to the overgrowth of central giant cell granuloma, ossifying fibroma, fibrous dysplasia, etc., in the secondary type ABC.
Some asteroid specimens were collected at a depth of 150 m near Moseulpo in Jeju Island, Korea using fishing nets on October 2014. The specimens were identified as Henricia pacifica Hayashi, 1940 belonging to the family Echinasteridae of order Spinulosida. In the Korean fauna, seven species of genus Henricia were reported of which two species, H. nipponica and H. ohshimai, were distributed in Jeju Island. The morphological characteristics of this species were re-described with illustrations.