• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.2
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• pp.94-99
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• 2005

The gametogenesis of the surf clam, Tresus keenae, were investigated by SEM and TEM. Both the testis and the ovary had follicle tubes surrounded by inter-tubal tissue composed of adipogranular cells that provided storage function. In the vitellogenic oocyte, lipid droplets and lipid yolk granules were found in the vacuoles formed by the Golgi apparatus. Proteid yolk granules were formed by the endoplasmic reticulum and cortical granules in the cytoplasm during vitellogenesis. The mature sperm was primitive and resembled a jar with a cover. The sperm heads were approximately $2.00-2.30 {\cal}um$. The acrosomal rod projected in front of the acrosome. In addition, four large mitochondria were in the midpiece.

• The Korean Journal of Malacology
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• v.22 no.1 s.35
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• pp.51-61
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• 2006

Oogenesis and the reproductive cycle in female Ruditapes philippinarum were investigated by cytological and histological observations. R. philippinarum is dioecious and oviparous. During vitellogenesis, the Golgi complex, glycogen particles and mitochondria were involved in the formation of lipid droplets and lipid granules in the cytoplasm of the early vitellogenic oocyte. In the late vitellogenic oocyte, cortical granules, the endoplasmic reticulum, and mitochondria were involved in the formation of proteid yolk granules in the cytoplasm. At this time, exogenous lipid granular substance and glycogen particles in the germinal epithelium passed into the oocyte through the microvilli of the vitelline envelope. The spawning period was once a year between early June and early October, and the main spawning occurred between July and August when seawater temperature was approximately $20^{\circ}C$. The reproductive cycle of this species can be categorized into five successive stages: early active stage (January to March), late active stage (February to May), ripe stage (April to August), partially spawned stage (May to October), and spent/inactive stage (August to February). Percentages of female clams at frst sexual maturity of 15.1-20.0 mm in shell length were 52.6% (50% of the rate of group maturity was 17.83 mm in length), and 100% for the clams > 25.1 mm.

• Animal Systematics, Evolution and Diversity
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• v.27 no.3
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• pp.220-227
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• 2011

The morphology of the two marine urostyloid ciliates, Pseudokeronopsis carnea (Cohn, 1866) and Uroleptopsis citrina Kahl, 1932, in the family Pseudokeronopsidae, collected from the Yellow Sea, and the East Sea, Korea, respectively, were studied using live observation and protargol impregnation. Additionally, the small subunit ribosomal RNA (SSU rRNA) gene was sequenced. These two species are firstly recorded in Korea. The main diagnostic key is as follows. Pseudokeronopsis carnea: body outline elongate-elliptical, brown-reddish or orange-red in colour in vivo; bicorona of 16-24 frontal cirri; one buccal and two frontoterminal cirri; 7-10 transverse cirri; 5-7 dorsal kineties; two types of cortical granules (one orange-red pigment, mainly grouped around cirri and dorsal bristles, arranged in typical rubra-pattern; the other, colourless and blood-cell-shaped, and densely distributed); contractile vacuole in the posterior half of the cell on the left side, usually in posterior 1/3-2/5. Uroleptopsis citrina: body outline elongate-elliptical, lemon-yellow in colour in vivo; two types of cortical granules (one yellow pigment; the other, blood-cell-shaped, densely distributed); bicorona of 12-18 frontal cirri; 2-3 frontoterminal cirri; two midventral rows comprising 26-35 cirri (consisting of anterior paired cirri, non-paired single cirri, and posterior paired cirri); three dorsal kineties. In addition, the SSU rRNA sequences of the two species were compared with public database of these species and consequently, showed high similarity.

• Animal Systematics, Evolution and Diversity
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• v.27 no.3
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• pp.228-238
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• 2011

Two urostyloid ciliates, collected from brackish water in Korea, were identified as Diaxonella pseudorubra pseudorubra (Kaltenbach, 1960) Berger, 2006 and Pseudokeronopsis flava (Cohn, 1866) Wirnsberger, Larsen and Uhlig, 1987. The description was based on living, protargol impregnated specimens. These species are described as follows: Diaxonella pseudorubra pseudorubra: body size in vivo $145-230{\times}40-60\;{\mu}m$, elongated ellipsoidal in shape. Cytoplasm reddish and flexible. Adoral zone of membranelles occupied 30-40% of the body; composed of 33-44 membranelles; 1-3 frontoterminal cirri, 1-4 frontal row cirri, 4-6 buccal cirri, 6-10 transverse cirri. Midventral rows composed of 14-24 cirri, four left marginal rows, one right marginal row. Two kinds of cortical granules; the larger one is yellowish and the smaller one is reddish. Pseudokeronopsis flava: body size in vivo $150-210{\times}30-45\;{\mu}m$, elongated ellipsoidal shape. Cytoplasm yellowish and flexible. Adoral zone of membranelles occupied 25-30% of body; composed of 44-58 membranelles in number. Frontal cirri forming bicorona composed of 5-7 cirral pairs, 2-3 frontoterminal cirri, one buccal cirrus, and 2-3 transverse cirri. Midventral rows composed of 18-33 cirri, 34-53 left marginal cirri, and 40-58 right marginal cirri. Two kinds of cortical granules; the larger one is colorless and "blood-cell-shaped," and the smaller one is yellowish. Diaxonella pseudorubra pseudorubra is different from the most similar subspecies, D. pseudorubra pulchra, in cytoplasmic color and number of midventral cirri. Pseudokeronopsis flava is different from its most similar congeners in pigment granular color, number of bicorona, number of midventral cirri, and position of the contractile vacuole.

• Animal Systematics, Evolution and Diversity
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• v.28 no.3
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• pp.168-177
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• 2012

Two stichotrichid ciliates, collected from marine waters in Jeju Island, were identified as Afroamphisiella multinucleata Foissner et al., 2002 and Pseudokahliella marina (Foissner et al., 1982) Berger et al., 1985. They are recorded for the first time in Korea. The descriptions are based on examinations of living as well as protargol-impregnated specimens. These species are characterized as follows. Afroamphisiella multinucleata has a body size in vivo of $70-95{\times}20-35{\mu}m$; elongate rectangular in shape; contractile vacuole located slightly above mid-body. The adoral zone is bipartited into 3 distal and 13-17 proximal membranelles and occupies 28-35% of the body length. The frontal row comprises 1-4 cirri and one buccal cirrus. The amphisiellid median cirral row is composed of 14-21 cirri, 10-19 left marginal cirri, and 21-30 right marginal cirri. Cortical granules are yellowish. 11-20 globular/ellipsoidal macronuclear nodules arrange proximally along the cell margins. Pseudokahliella marina has a body size in vivo of $110-195{\times}40-110{\mu}m$ and broadly elliptical in shape. The adoral zone of the membranelles occupies 50-60% of the body length, and is composed of 41-70 membranelles. A prominent frontal scutum is present. The contractile vacuole is located below the mid-body. There are 11-13 frontoventral rows, including marginal rows. Caudal cirri and transverse cirri are absent. Three invariable non-fragmented bipolar dorsal kineties are present. The left and right marginal rows are composed of 22-35 and 28-40 cirri, respectively. Colourless cortical granules are present. 8-11 spherical/ellipsoidal macronuclear nodules are connected with each other by thread-like tructures, forming an inverted C-shape.

• Korean Journal of Agricultural Science
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• v.48 no.1
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• pp.163-170
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• 2021

Bacterial infections in the female reproductive tract negatively affect ovarian function, follicular development, and embryo development, leading to the eventual failure of fertilization. Moreover, bacterial lipopolysaccharides (LPS) can interfere with the immune system and reproductive system of the host animal. Therefore, this study examined the effect of LPS on the in vitro maturation (IVM) of pig oocytes. Oocytes were matured in TCM199 medium in the presence of varying concentrations of LPS (0 - 50 ㎍·mL^-1). The maturation rate, cortical granules (CGs) migration, and chromosome alignment were subsequently evaluated during the meiotic development of the oocytes. We observed a dose-dependent and significant decrease in the metaphase II (MII) rate with increasing concentrations of LPS (97.6% control [0 ㎍·mL^-1 LPS] vs. 10.4-74.9% LPS [1 - 50 ㎍·mL^-1], p < 0.05). In addition, compared to the control oocytes without LPS, higher levels of abnormal CGs distribution (18.1 - 50.0% LPS vs. 0% control), chromosome/spindle alignment (20.3 - 56.7% LPS vs. 0% control), and intracellular ROS generation were observed in oocytes matured with LPS (p < 0.05). Nitrite levels were also increased in the maturation medium derived from the oocytes matured with LPS (p < 0.05). These results indicate that LPS induces oxidative stress during IVM and affects oocyte maturation, including CGs migration and chromosome alignment of pig oocytes.

• Animal Systematics, Evolution and Diversity
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• v.28 no.1
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• pp.20-28
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• 2012

Two urostylid ciliates, Anteholosticha pulchra (Kahl, 1932) Berger, 2003 and Metaurostylopsis struederkypkeae Shao et al., 2008, new to Korea, were collected from the Yellow Sea and the East Sea, Korea, respectively. They were identified based on live observation and protargol impregnation. Taxonomical characters of A. pulchra are as follows: $190-300{\times}30-55\;{\mu}m$ size in vivo; contractile vacuole located on the left side of the posterior 1/4 of the cell; spherical-reddish granules at cirral bases and around dorsal bristles, somewhat sparsely distributed throughout the cell surface; four frontal and two frontoterminal cirri; four dorsal kineties; caudal cirri absent. Metaurostylopsis struederkypkeae is characterized as follows: $80-110{\times}40-50\;{\mu}m$ size in vivo; caudal cirri absent; two types of cortical granules: type 1, yellow-green arranged along the ventral cirral rows and dorsal kineties; type 2, small and reddish, with an irregular arrangement; four frontal, four to eight frontoterminal, and two to six transverse cirri; five to seven left and three to five right marginal rows. Sequences of small subunit ribosomal DNA were determined from both species, and pairwise distances with their relatives were analyzed.

• Animal Systematics, Evolution and Diversity
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• v.26 no.3
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• pp.307-316
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• 2010

To investigate the Korean ciliate fauna, two oxytrichid ciliates, Laurentiella strenua (Dingfelder, 1962) and Notohymena australis (Foissner and O'Donoghue, 1990) were collected from the Taehwa River in Ulsan, South Korea. These two ciliates are reported for the first time in Korea. Descriptions were based on the observation of live and silver stained specimens. Diagnoses of these species are as follows: Laurentiella strenua: body is approximately $320{\times}170\;{\mu}m$ in size, an inverted triangular shape. Cytoplasmic globules are present in both anterior and posterior margins, transparent and sized $10-15\;{\mu}m$ in live specimens. Adoral zone of membranelles is covering about 50% of body length. Frontoventral-transverse cirri are arranged diagonally into 5 rows. Transverse cirri are arranged almost longitudinally and varied 4-6 in number. Dorsal kineties are 11 rows with multiple fragmentations. Macronuclei are 4-5 in number. Notohymena australis: body is approximately $170{\times}50\;{\mu}m$ in live specimens, slender and long ellipsoidal shape. Yellowish green cortical granules are present as pairs or rows which composed of 3-6 granules. Adoral zone of membranelles is covering about 36% of the body length, composed of 39-50 adoral membranelles. Dorsal kineties is 6 rows. Macronuclei are 2 in number.

• Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.97-108
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• 2005

Five species of red algae were recorded for the first time in Korea: Acrochaetium plumosum (Drew) Smith, Gelidium australe J. Agardh, Gelidium galapagense Taylor, Cryptonemia lactuca (c. Agardh) J. Agardh, and Kallymenia harveyana J. Agardh. Their habitats and morphological characters were described with illustrative figures. Acrochaetium plumosum is characterized by obovoid to clavate cells with thick walls, stellate chloroplasts with a central pyrenoid, mono sporangia that are produced singly or in a: concatenate form of two, and branching secundly and distichously. Gelidium australe is characterized by terete and slightly compressed axes and branches, terete and slightly contorted branchlets, and spatulate to lanceolate forms of tetrasporangial stichidia. Gelidium galapagense is characterized by a thallus composed of stolons and erect foliaceous branches with short digitate branchlets, and palmate forms of tetrasporangial stichidia. Cryptonemia lactuca is characterized by flabellate, subcartilagineous, strongly undulate, di-polychotomously laciniate thalli, with a midrib in the lower portion of the thallus, and tetrasporangia in the cortical layer of the small segments formed on the apical margin of the blade. Kallymenia harveyana is characterized by the gelatinoid and laminate thallus with a very short stipe, with the cortical cells compacted with small granules, and stellate cells in the medulla.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2005.04a
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• pp.3-14
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• 2005

To investigate phytotoxic substances in some donor plants and their biological activities, seed germination and seedling growth of receptor plants were examined at different concentrations of aqueous extracts and essential oils of the donor plants. Germination of some receptor species was inhibited by the extracts, while seedling growth was decreased to a lesser degree than in the germination test. Germination, seedling growth and dry weight growth of Achyranthes japonica grown in pot were proportionally inhibited by the extracts. Volatile substances emitted some donor plants caused inhibitory effects in the germination and seedling growth of the receptor species. Essential oil of the plants extracted by Karlsruker's apparatus Inhibited growth of microorganisms, callus growth and root hair development of receptor plants. The cortical cells at the root tips of Latuca sativa treated with essential oils showed contraction of the cytoplasm, resulting in plasma membranes becoming detached from the cell walls and the cells metamorphosing irregularity. Accumulation of lipid granules Inside contracted cytoplasm and degeneration of mitochondrial cristae were also observed. The GC/MS method was employed for analysis and identification of allelochemicals from donor plants. Sixty-one chemical substances such as camphene, cineole etc. were identified from essential oils of Artemisia argyi.