• 한국동물학회지
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• 제39권1호
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• pp.54-64
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• 1996

Xenopus를 사용하여 후각원판이 정상적인 상태에서 어떠한 과정을 거쳐 발달하는지 연구하였다. 특히 뉴런의 형태적 분화, 초기 발달과 성숙 양상, 축색과 원시전뇌의 접촉 등에 초점을 맞추었다. 후각원판은 stage 23에 외배엽이 두터워진 형태로 처음 나타나는데, 쌍을 이루며 각각은 표피측에 비신경층(NNL)과 안쪽의 신경층(NL)의 두 층으로 되어 있다. stage 26 후에 원판 세포는 NNL세포 틈을 비집고 상피쪽으로 이동하기 시작하며, stage 28이 되면 선단 돌기가 표피 끝에 도달한다. stage 29/30에는 NL의 기부에서 기부 돌기(미래의 축색)가 나타나 stage 32무렵 종뇌에 도달한다. 시냅스는 stage 37/38에 처음 나타난다. 일부 원판 세포들이 후각 뉴런으로 분화하는 동안 많은 원판 세포들은 기저세포로서 후각상피에 그대로 남아 있다. 연구 결과는 뉴런 외배엽의 NL에서 기원하고 지지세포는 NNL층에서 기원함을 보여주었다. 또한 시냅스 형성 전에 뉴런의 분화가 완성됨으로써 후각뉴런의 분화는 뇌의 발달과 독립적으로 일어나며 뇌의 영향을 받지 않는다는 사실을 알 수 있었다.

• Animal cells and systems
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• 제1권3호
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• pp.491-496
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• 1997

When olfactory placodes are transplanted at stages 23/24 from Xenopus laevis to Xenopus borealis hosts of the same age, it is possible to distinguish the cell populations of the host and donor due to the peculiar nuclear Q bands specific to X. borealis. I have replaced the eye anlage in each of a number of X. borealis with the transplanted olfactory placode of an individual X. laevis, or vice versa. In most instances, the placode of the donor fuses with that of the host. When fusion occurs, but not when the host and donor orqans grow separately, the cells of the donor were replaced gradually and according to a characteristic pattern by cells of the host. The basal cells of the donor were the first to be replaced, followed by the more matured cells of the sensory epithelium. This cellular substitution, proceeding in an orderly fashion from bottom to upper layers of the epithelium, depends on the fusion of the two organs. This observation suggests intercellular contacts in the mitotic zone of the two organs favor the host's cells over those of the donor.

• BMB Reports
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• 제42권10호
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• pp.631-635
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• 2009

The heat shock transcription factor (HSF) family consists of at least three members in mammals and regulates expression of heat shock proteins in response to heat shock and proteotoxic stresses. Especially, HSF1 is indispensable for this response. Members of this family are also involved in development of some tissues such as the brain and reproductive organs. However, we did not know the molecular mechanisms that regulate developmental processes. Involvement of HSFs in the sensory development was implicated by the finding that human hereditary cataract is associated with mutations of the HSF4 gene. Analysis of gene-disrupted mice showed that HSF4 and HSF1 are required for the lens and the olfactory epithelium, respectively. Furthermore, a common molecular mechanism that regulates developmental processes was revealed by analyzing roles of HSFs in the two developmentally-related organs.

• Clinical and Experimental Reproductive Medicine
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• 제26권2호
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• pp.281-285
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• 1999

Kallmann's syndrome has both a general and specific connotation in describing general condition of gonadotropin-releasing hormone (GnRH) deficiency or a particular cluster of anomalies associated with primary eunuchoidism. The familial occurrence of hypogonadotropic hypogonadism associated with anosmia, color blindness, synkinesia, and mental defect is the classic Kallmann's syndrome. Interestingly, anosmia, or lack of smell, was not found in the absence of gonadal deficiency in the original study of this disorder. This disorder was found on both sexes, but the male to female ratio was 11:1, and Kallmann's syndrome is more often listed under disorders of male hypogonadism for this reason. Gross anatomy has shown disorders of the olfactory bulbs associated with Kallmann's syndrome and it was demonstrated a failure of GnRH-containing cells to migrate from the olfactory placode to the hypothalamus and preoptic area. We have experienced a case of Kallmann's syndrome which showed a hypoplasia of olfactory bulb in MRI during the workup of primary amenorrheic patient. So we report this case with a brief review of literatures.

• 대한수의학회지
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• 제55권3호
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• pp.181-184
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• 2015

Ciliary rootlet coiled coil protein (CROCC), the structural component that originates from the basal body at the proximal end of the ciliary rootlet, plays a crucial role in maintaining the cellular integrity of ciliated cells. In the current study, we cloned Xenopus CROCC and performed the expression analysis. The amino acid sequence of Xenopus laevis was related to those of Drosophila, cow, goat, horse, chicken, mouse and human. Reverse transcription polymerase chain reaction analysis revealed that CROCC mRNA encoding a coiled coil protein was present maternally, as well as throughout early development. In situ hybridization indicated that CROCC mRNA occurred in the animal pole of embryo during gastrulation and subsequently in the presumptive neuroectoderm at the end of gastrulation. At tailbud stages, CROCC mRNA expression was localized in the anterior roof plate of the developing brain, pharyngeal epithelium connected to gills, esophagus, olfactory placode, intestine and nephrostomes of the pronephric kidney. Our study suggests that CROCC may be responsible for control of the development of various ciliated organs.