• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.91-96
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• 1998

In relation to cold acclimation, this experiment was carried out to understand the changes of the cortical cells in the living barks of the mulberry during wintering period. The living barks of three mulberry varieties(Kaeryangppong, Shinilppong and Yongcheonppong) were sampled from December, 1995 to March, 1996. The result of this experiment was summarized as follows. The cortical cells in the living barks of the mulberry in December were filled with small vacuoles. Plastids and mitochondrias were located near the nucleus. At this time, almost all starch granules disappeared from the plastids. In January and February, mitochondria, palstids and microbodys of the cortical cell were observed. As increasing temperature from March, dictysomes and polysomes were sparse. Again, starch granules disappeared were observed in the plastids. From the above result. starch granules in plastide of the cortical cell of the mulberry disappeared during cold acclimation stage. After late January, Proplastid was observed in the cortical cell and the ultrastructures of cortical cell were actively changed.

• Fibers and Polymers
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• v.6 no.3
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• pp.263-268
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• 2005

Alpaca fibers have some distinct properties such as softness and warmth, which have not been fully understood in combination with the fiber internal structures. In the present investigation, the internal structures of alpaca fibers have been closely examined under the scanning electron microscope (SEM), especially in the longitudinal direction. The results showed that numerous pigment granules reside loosely inside pockets in brown and dark-brown alpaca fibers. These pigment granules were mainly distributed inside the cortical cells, the medullation regions as well as underneath the cuticles. Their size in the brown alpaca fibers was smaller and more uniformly round than in the dark-brown fibers. These granules in colored alpaca fibers loosen the bundle of cortical cells, providing many crannies in the fibers which may contribute to the superior flexibility, warmth and softness of the fibers. Moreover, there are no heavy metal elements found in the granules. The mordant hydrogen peroxide bleaching employed could eliminate the pigment granules and create many nano-volumes for further dyeing of fibers into more attractive colors.

• Korean Journal of Animal Reproduction
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• v.20 no.3
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• pp.343-351
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• 1996

The objectives of this study are to determine cortical granule distribution during in vitro maturation, parthenogenetic activation and in vitro fertilization of oocytes, and to investigate effects of microfilament inhibitor on the cortical granule distribution during in vitro maturation and fertilization of oocytes in the pig, The corti-cal granule distribution were imaged with fluor-escent labeled lectin under laser scanning confocal microscope or detected by transmission electron microscope. At germinal vesicle stage, cortical granule organelles were located around the cell cortex and were present as a relatively thick area on the oolema. Microfilaments were also observed in a thick uniform area around the cell cortex. Following germinal vesicle break down,microfilaments concentrated to the condensed chromatin and cortical granules were observed in the cortex. Treatment with cytochalasin B inhibited microfilament polymerization and prevented movement of cortical granules to the cortex. Cortical granule exudate following sperm penetration was evenly distributed in the entire perivitelline space. Therefore, these results suggested that the microfilament assembly is involved in the distribution, movement and exocytosis of cortical granules during maturation and fertilization of porcine oocytes. (Key words cortical granule, porcine, maturation, fertilization).

• Animal cells and systems
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• v.9 no.2
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• pp.57-64
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• 2005

Cortical reaction and polyspermy block are well defined in most marine invertebrates. In Urechis species, the function of cortical granules (CGs) is not yet known, and there is controversy on whether the cortical reaction occurs, or the fertilization envelope (FE) is attributed to CG releases or functions to prevent polyspermy. This study was carried out to determine the cortical reactions and functions of the FE in Urechis unicinctus. Artificial insemination of the eggs revealed that CG release occurred to give rise to perivitelline space (PS) into the final FE. Both PS and final FE effectively blocked polyspermy. The final FE was accomplished within 10 min after sperm-egg initial binding. No massive release of CGs occurred within the early phase of 5 min after the initial binding, initially and the PS seemed to playa role to prevent polyspermy. The CG massively released its content into the PS in late phase of FE formation, and differentiated PS into five intermediate layers. The layers opened into each other by anastomosis, so that the final FE consisted of two layers, the inner layer ($15{\mu}m$ in thickness) and the outer layer ($1{\mu}m$ in thickness). The outer layer derived from vitelline layer and the inner layer consisted of PS and CG secretions. Immunofluorescence and confocal laser microscopy revealed that the spermatozoon took up residence in the egg cortex during FE formation and successive meioses of the fertilized egg. These results suggest that both PS and final FE of U. unicinctus were equivalent to the early and late block, respectively, of other marine animals.

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.45-56
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• 2005

Three species of Gastrostyla ciliates collected from the sewage treatment plant and a puddle in the valley from Korea were identified as Gastrostyla minima Hemberger, 1985, G. steinii Engelmann, 1862 and G. setifera (Engelmann, 1862). The description was based on the observation of living specimens, protargol impregnated specimens and biometric analysis. The morphological variations among the populations of these species were investigated with morphometry. These species have not been reported in Korea and their diagnostic characteristics are as follows: G. minima normally has two oval macronuclei (Ma) with one spherical micronucleus (Mi) respectively, continuous ventral cirral row (VCR) with additional one postoral ventral cirrus (poVC), five transverse cirri (TC), six dorsal kineties (DK) with broken 4th kinety, and cortical granules. G. steinii has four oval Ma with three to five Mi, discontinuous VCR with additional one poVC, four TCs, six DKs, and no cortical granules. G. setifera has two oval Ma with one spherical Mi respectively, five TCs which distinctly separate in two groups, six DKs, discontinuous VCR with additional two poVCs, and no cortical granules.

• Journal of Species Research
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• v.1 no.1
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• pp.78-86
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• 2012

Three ciliate species of genus Cyrtohymena, C. australis Foissner, 1995, C. citrina (Berger & Foissner, 1987) and C. muscorum (Kahl, 1932) new to Korea, were collected from semi-terrestrial habitats. The description was based on the observation of live and silver stained specimens. Diagnostic characteristics of these species are as follows. C. autralis: size about $275{\times}100{\mu}m$ in live specimens. Cortical granules yellowish. 18-31 right and 31-40 left marginal cirri in number. Dorsal kineties eight rows. C. citrina: size about $180{\times}50{\mu}m$ in live specimens. Cortical granules yellowish. 26-32 right and 23-27 left marginal cirri in number. Dorsal kineties five to six rows. C. muscorum: size about $180{\times}60{\mu}m$ in live specimens. Cortical granules reddish. 31-34 right and 33-36 left marginal cirri in number. Dorsal kineties six rows. Three species of Cyrtohymena have been added to Korean ciliate fauna from this study. Including previous one species of C. quadrinucleata, four species of this genus in total have been recorded so far in this country.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.07a
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• pp.52-52
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• 2005

Oogenesis, the gonadosomatic index (GSI), reproductive cycle and first sexual maturation of the female Neptunea (Barbitonia) arthritica cumingii have been investigated by light and electron microscope observations. In the early vitellogenic oocyte, the Golgi complex and mitochondria were involved in the formation of glycogen, lipid droplets and yolk granules. In late vitellogenic oocytes, the rough endoplasmic reticulum and multivesicular bodies were involved in the formation of proteid yolk granules in the cytoplasm. In particular, compared with the results of other gastropods, it is a different result that appearances of cortical granules at the cortical layer and microvilli on the vitelline envelope, which is associated with heterosynthetic vitellogenesis, were not observed in vitellogenic oocytes during oogenesis. A mature yolk granule was composed of three components: main body (central core), superficial layer, and the limiting menbrane, Monthly changes in the gonadosomatic index in females were studied in 2002 and 2003 were closely associated with ovarian developmental phases. Spawning occurred between May and August in 2002 and 2003 and the main spawning occurred between June and July when the seawater temperature rose to approximately 18${\sim}$23${\circ}$C. The female reproductive cycle can be classified into five successive stages: early activestage (Septmber to October), late active stage ( November to February), ripe stage (February to June), partially spawned stage (May to Aygust), and recovery stage (June to August).

• The Korean Journal of Malacology
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• v.22 no.1 s.35
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• pp.1-11
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• 2006

The gonadosomatic index (GSI), oogenesis and reproductive cycle in female Neptunea (Barbitonia) afhritica cumingii were investigated by light and electron microscope observations. In the early vitellogenic oocyte, the Golgi complex and mitochondria were involved in the formation of glycogen, lipid droplets and yolk granules. Late in the vitellogenic oocytes, the rough endoplasmic reticulum and multivesicular bodies were involved in the formation of proteid yolk granules in cytoplasm. In particular, compared with the results of other gastropods, it showed a different result that appearances of cortical granules at the cortical layer and microvilli on the vitelline envelope, which is associated with heterosynthetic vitellogenesis, were not observed in vitellogenic oocytes during oogenesis. A mature yolk granule was composed of three components: main body (central core), superficial layer, and the limiting membrane. Monthly changes in the gonadosomatic index in females studied in 2004 and 2005 were closely associated with ovarian developmental phases. Spawning occurred between May and August in 2004 and 2005 and the main spawning occurred between June and July when the seawater temperature rose to approximately $18-23^{\circ}C$. The female reproductive cycle can be classified into five successive stages: early active stage (September to October), late active stage (November to February), ripe stage (February to June), partially spawned stage (May to August), and recovery stage (June to August).

• Korean Journal of Environmental Biology
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• v.33 no.4
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• pp.383-389
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• 2015

We identified two soil stichotrichs, Eschaneustyla lugeri Foissner, Agatha & Berger, 2002 and Oxytricha auripunctata Blatterer & Foissner, 1988, which were collected from Sarabong, Jeju and Ajoong-ri, Jeonju in Korea, respectively. Eschaneustyla lugeri had the following characteristics: size in vivo $170-230{\mu}m{\times}40-60{\mu}m$; body elongate elliptical and often very narrow in the posterior region, highly flexible; cortical granules present; 48-67 macronuclear nodules; 27-47 frontal cirri; 3-5 buccal cirri; frontoterminal row and rightmost midventral row; transverse cirri absent; 4 dorsal kineties; 4-9 caudal cirri. Oxytricha auripunctata had the following characteristics: size in vivo $75-95{\mu}m{\times}25-35{\mu}m$; body elliptical, both ends moderately narrowly rounded; orange-yellow cortical granules and yellowish crystals; 3-4 transverse cirri; 5 dorsal kineties; 3 caudal cirri. These two ciliates are first reported in Korea. We describe these ciliates based on live observations and protargol-impregnated specimens.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.59-65
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• 2011

For investigation of the Korean ciliate fauna, two oxytrichid ciliates, Histriculus histrio (Muller, 1773) and Sterkiella thompsoni Foissner, 1996, were collected from freshwater and brackish waters in South Korea, respectively. These two ciliates are reported for the first time in Korea. Descriptions were based on observations of live and silver stained specimens. Diagnoses of these species are as follows. Histriculus histrio: body is approximately $190{\times}85\;{\mu}m$ in size, almost ellipsoidal in shape, posterior part rather thin and very translucent. Cortical granules are absent. Both marginal rows are almost confluent at the posterior end. Six dorsal kineties are present. Sterkiella thompsoni: body is approximately $140{\times}50\;{\mu}m$ in size. Body margins are usually in parallel. Cortical granules are absent. Invariably, four dorsal kineties are present. Two caudal cirri are located on the dorsal surface. Three ellipsoidal macronuclear nodules are present.