• 식물분류학회지
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• 제44권4호
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• pp.288-297
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• 2014

이 연구의 목적은 우리나라에서 식물학이 시작된 이후 57년이 넘도록 나자식물 분류군에 대하여 다음과 같이 잘못 인식되어 온 관행의 원인을 분석하는 데 있다. 즉, 수많은 식물(분류)학 관련 매체들에서, 나자식물(꽃이 피지 않는 종자식물)의 생식구조(cone 및 pollen)에 관한 용어 및 기재에 피자식물(꽃이 피는 종자식물)에서 사용되는 생식기관(꽃)의 용어들을 그대로 적용하여 쓰고 있다. 이로 인하여, 마치 나자식물이 꽃이 피는 식물(피자식물)인 것처럼 오도되고 있다. 특히, 이러한 오류의 관행은 각급 학교에서 교사와 학생들이 꽃에 대한 개념 및 정의를 이해하는 데 있어서 커다란 혼란을 불러 일으키고 있으며, 이는 식물(분류)학 교육에 심각한 문제가 아닐 수 없다. 따라서 많은 식물학 관련 매체들로부터 나자식물에 대하여 잘못 표현된 용어 및 기재를 조사하여, 이를 분계도, 생식구조의 해부학, 분류체계의 역사적 배경 등의 관점에서 분석하고 논의하였다.

• 통합자연과학논문집
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• 제1권3호
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• pp.195-209
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• 2008

Some Korean terminologies on reproductive structures of seed plants in plant morphology, written incorrectly in many books, were analysed to propose accurately expressed terminologies. 31 books in areas such as general biology, plant biology, plant morphology, and biological dictionaries and glossaries were selected to analyse the accuracy of the terminologies for reproductive structures in gymnosperms, e.g., cone or strobilus, seed (or ovulate) cone and pollen cone, and conifer(s) or coniferous plants, and for flower structures in angiosperms, e.g., corolla, anther, filament, pistillate (or female) flower and staminate (or male) flower, apocarpous, and syncarpous. The definition and etymology of the terminologies were traced in 4 textbooks of plant anatomy and 2 dictionaries of biology and botany written in English. On the basis of the definition, etymology, and principles for terminology formation according to the International Organization for Standardization (ISO 704:2000), reasonably expressed Korean terminologies were proposed. All of the 8 terminologies examined in this study were included in the glossary of biological terminologies, published by the Korean Association of Biological Sciences in 2005, and designated as an editorial source for science and biology textbooks for middle and high schools by Ministry of Education in 2007. However, the only 1 of the 8 terminologies described in the glossary were consistent with the proposed expression in the present study. These inconsistencies indicated the need for a reassessment of this glossary of biological terminologies. The newly proposed terminologies would facilitate mutual understanding between teachers and students of plant biology.

• Clinical and Experimental Reproductive Medicine
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• 제38권4호
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• pp.216-221
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• 2011

Objective: To differentiate the human embryonic stem cells (hESCs) into the retinal pigment epithelium (RPE) in the defined culture condition and determine its therapeutic potential for the treatment of retinal degenerative diseases. Methods: The embryoid bodies were formed from hESCs and attached on the matrigel coated culture dishes. The neural structures consisting neural precursors were selected and expanded to form rosette structures. The mechanically isolated neural rosettes were differentiated into pigmented cells in the media comprised of N2 and B27. Expression profiles of markers related to RPE development were analyzed by reverse transcription-polymerase chain reaction and immunostaining. Dissociated putative RPE cells ($10^5$ cells/5 ${\mu}L$) were transplanted into the subretinal space of rat retinal degeneration model induced by intravenous sodium iodate injection. Animals were sacrificed at 1, 2, and 4 weeks after transplantation, and immnohistochemistry study was performed to verify the survival of the transplanted cells. Results: The putative RPE cells derived from hESC showed characteristics of the human RPE cells morphologically and expressed molecular markers and associated with RPE fate. Grafted RPE cells were found to survive in the subretinal space up to 4 weeks after transplantation, and the expression of RPE markers was confirmed with immunohistochemistry. Conclusion: Transplanted RPE cells derived from hESC in the defined culture condition successfully survived and migrated within subretinal space of rat retinal degeneration model. These results support the feasibility of the hESC derived RPE cells for cell-based therapies for retinal degenerative disease.

• ALGAE
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• 제32권2호
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• pp.87-100
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• 2017

The genera Hypnea and Calliblepharis of the family Cystocloniaceae are discriminated by their female reproductive structure, especially in the formation of carposporangia and gonimoblasts. Hypnea saidana, once classified based on obsolete evidence, has not been studied phylogenetically using molecular analysis and detailed reproductive structure though it shares many morphologic features with the genus Calliblepharis. To provide better understanding of generic relationship of H. saidana with Hypnea and Calliblepharis, we carried out molecular analyses using the nuclear-encoded small subunit ribosomal DNA (SSU) and chloroplast-encoded large subunit of the RuBisCO (rbcL), and exact morphological observations focusing on the reproductive structures of wild specimens. Our molecular phylogeny showed that H. saidana is closely related to Calliblepharis, but distinct from the clade of Hypnea. Female reproductive structure of H. saidana characterized by upwardly developing chains of carposporangia, central reticulum of cell, and gonimoblast filaments not connected to the pericarp provides definite evidence to assign the taxonomic position of this species to Calliblepharis. Based on our combined molecular and morphological analyses, we have proposed Calliblepharis saidana comb. nov., expanding the distribution of Calliblepharis habitat from the eastern Atlantic South Africa, the northern Indian Ocean, Australasia, and Brazil to the western Pacific Ocean.

• Clinical and Experimental Reproductive Medicine
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• 제18권1호
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• pp.101-105
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• 1991

Although many therapies have been advocated in the treatment of idiopathic male infertility, the results of treatment are poor. This probably seems to be due to a lack of one or more proteins constituting the key structures of the spermatozoa. We evaluated the functional structures of the spermatozoa in 11 infertile patients whose semen showed severe oligoasthenozoospermia with immunochemical method and found a case with spermatozoa lacking acrosin. Evaluation of the spermatozoal defect with immunochemical method is desirable in patients with severe oligoasthenozoospermia, especially in cases unresponsive to medical therapy.

• ALGAE
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• 제19권3호
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• pp.161-174
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• 2004

Phonological, morphological and molecular characteristics of Spatoglossum pacificum Yendo are examined. S. pacificum has an annual life cycle composed of saprophytes with apparent absence of male and female gametophytes in Korea. The seasonal growth of this species explains that the annual growth is closely related to the monthly variation of water temperature. S. pacificum has protruding reproductive structures above the outmost cortical layer. Although this observation is restricted to several species, reproductive structures on the thallus can make S. pacificurn distinguishable from S. crassum and S. lacturn. The morphogenesis of a midrib at the base of S. pacificum in this study is the same as those of Dictyopteris but different from those of S. crassum and S. lacturn, suggesting that S. pacificum is closely related to Dictyopteris. In the comparison of plastid gene sequences among species of Spatoglossum and Dictyopteris, S. pacificum is more similar to D. divaricata and D. undulate than those of S. crassum in rbcL, rbcS, psbA and psaA. This result is congruent with the anatomical characteristic of a midrib at the base of the thallus and the protrusion of reproductive organs on the thallus. The phylogenetic relationship based on these plastid genes also shows that S. pacifism is included in Dictyotpteris Glade and separated from S. crassum. We propose the new combination of Dictyopteris pacifica (Yendo) I.K. Hwang, H.S. Kim et W.J. Lee, comb. nov. based on the differences of anatomical characteristics of the midrib, the existence of reproductive organs on thallus and the molecular analyses.

• Clinical and Experimental Reproductive Medicine
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• 제49권4호
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• pp.259-269
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• 2022

Objective: Animal-free scaffolds have emerged as a potential foundation for consistent, chemically defined, and low-cost materials. Because of its good potential for high biocompatibility with reproductive tissues and well-characterized scaffold design, we investigated whether polyglycolic acid (PGA) could be used as an animal-free scaffold instead of natural fibrin-agarose, which has been used successfully for three-dimensional human endometrial cell culture. Methods: Isolated primary endometrial cells was cultured on fibrin-agarose and PGA polymers and evaluated various design parameters, such as scaffold porosity and mean fiber diameter. Cytotoxicity, scanning electron microscopy (SEM), and immunostaining experiments were conducted to examine cell activity on fabricated scaffolds. Results: The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay and SEM results showed that endometrial cells grew and proliferated on both scaffolds. Immunostaining showed cytokeratin and vimentin expression in seeded cells after 7 days of culture. On both scaffolds, an epithelial arrangement of cultured cells was found on the top layer and stromal arrangement matrix on the bottom layer of the scaffolds. Therefore, fibrin-agarose and PGA scaffolds successfully mimicked the human endometrium in a way suitable for in vitro analysis. Conclusion: Both fibrin-agarose and PGA scaffolds could be used to simulate endometrial structures. However, because of environmental and ethical concerns and the low cost of synthetic polymers, we recommend using PGA as a synthetic polymer for scaffolding in research instead of natural biomaterials.

• ALGAE
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• 제23권2호
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• pp.141-150
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• 2008

Populations of Codium amplivesiculatum were found in association with rhodolith beds. We present population trends of C. amplivesiculatum from surveys conducted in the southwestern Gulf of California based on monthly sampling from June 1999 to August 2000. Surveys were conducted at 2 sites in the San Lorenzo Channel at depths of 8 - 12 m. The parameters measured were percent cover, biomass and structure in relation to size of the thalli. From each thallus the following measurements were taken: length and diameter, proportion of each thallus with reproductive structures and the degree of fragmentation (measured as number of small thalli). Mean biomass and cover varied seasonally with the maximum (1036.6 gm$^{-2}$ and 100% cover) present in June 2000 and the minimum in winter (0 gm$^{-2}$ and 0% cover). The longest fronds (3 m) occurred during July 1999 and August 2000, while the maximum diameters of 1.0 cm were present during October and November 1999. There were no significant linear relationships between length and diameter of the fronds, suggesting independent growth. Reproductive structures were common in June and July 1999 with monoic and dioic thalli present. Most fronds were monoic, and this is the first record of this feature for this species. Fragmentation occurred in September, and may be associated with stress from early gametangial reproduction and the combination of high temperatures and low nutrients. A hypothetical life cycle for the species is presented.

• Ocean and Polar Research
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• 제27권1호
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• pp.67-74
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• 2005

남해안의 동대만과 앵강만에 생육하는 거머리말 개체군의 생물계절학과 생식 능력을 2002년 9월부터 2003년 8월까지 조사하였다. 동대만의 퇴적물 입도는 앵강만보다 세립하였으며, 퇴적물의 유기물 함량도 유의하게 높았다. 동대만의 수온은 $7.5^{\circ}C$(2월)에서 $25.5^{\circ}C$(8월)까지 분포하였으며, 앵강만은$6.7^{\circ}C$(2월)에서부터 $25.2^{\circ}C$(9월)까지 분포하였다. 두 지역의 거머리말 개체군은 다년생의 생활사를 보였으며, 생식지의 생식 능력들은 동대만이 앵강만보다 유의하게 높았다. 동대만의 생식지는 2003년 2월부터 6월까지 출현하였으나, 앵강만에서는 2003년 3월부터 6월까지 출현하였다. 동대만에서 생식지의 생육밀도는 $11{\sim}33%$를 차지하였으나, 동대만에서는 5% 이하로 나타났다. 생식지의 구조적인 특징은 육수화서 내 열매와 종자 수를 제외하고 동대만에서 유의하게 높았다. 두 생육지에서 거머리말 개체군의 생식 단계의 출현 시기는 수온과 관계하는 것으로 사료되었다.

• 생명과학회지
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• 제21권3호
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• pp.406-411
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• 2011

TBTCl과 bisphenol A (BPA)가 등줄쥐의 번식에 어떠한 영향을 미치는지 알아보기 위하여, 등줄쥐를 비번식기에 포획하여 번식기 직전에TBTCl과 BPA를 근육 주사한 후, 4개월 간 사육하였다. 그 결과, 암 수 모두 체중 증가량에 차이가 없었고, 수컷 체내의 각 화합물의 체내 잔류량, 성체와 새끼(F1) 수컷에 대한 생식소중량지수(GSI) 및 정소와 부정소의 광학 및 전자현미경 조직상이 대조군과 별다른 차이점을 보이지 않았다. 그러나 TBTCl 투여군에서는 출생한 태아의 사망 빈도가 높고, BPA 투여군에서는 유산율이 대조군에 비해서 높았다. 이로부터, 비번 식기의 성체 등줄쥐에게 TBTCl과 BPA를 단기간 투여했을 때, 이들 물질은 체내에 장기간 잔류하지 않으며, 성체 및 다음 세대 수컷의 생식기관에 영향을 미치지 않지만, 수태된 태아의 발생을 저해하는 물질임이 밝혀졌다.