• Title/Summary/Keyword: Zoology

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Karyological Studies of an Anuran Species, Bufo kangii Yoon (물두꺼비의 核型에 관한 硏究)

  • Kang, Yung-Sun;Yangil Sunwoo
    • The Korean Journal of Zoology
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    • v.16 no.3
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    • pp.171-176
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    • 1973
  • Metaphases were obtained from the bone marrow cells of B. kangii Yoon, by means of direct air-drying technique. The karylogical characteristics of this species were as follows; 1) The diploid chromosome number was 22(2n=22) which might be divided into six large and five small homololgous chromosmes. 2) All homologous chromosomes of this species were metacentrics. 3) The secondary constriction was not found in all members of chromosomes. 4) There was no evidence for the existence of a specific sex chromosome pair in this species.

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Cell Lineage, Self-Renewal, and Epithelial-to-Mesenchymal Transition during Secondary Neurulation

  • Kawachi, Teruaki;Tadokoro, Ryosuke;Takahashi, Yoshiko
    • Journal of Korean Neurosurgical Society
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    • v.64 no.3
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    • pp.367-373
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    • 2021
  • Secondary neurulation (SN) is a critical process to form the neural tube in the posterior region of the body including the tail. SN is distinct from the anteriorly occurring primary neurulation (PN); whereas the PN proceeds by folding an epithelial neural plate, SN precursors arise from a specified epiblast by epithelial-to-mesenchymal transition (EMT), and undergo self-renewal in the tail bud. They finally differentiate into the neural tube through mesenchymal-to-epithelial transition (MET). We here overview recent progresses in the studies of SN with a particular focus on the regulation of cell lineage, self-renewal, and EMT/MET. Cellular mechanisms underlying SN help to understand the functional diversity of the tail in vertebrates.

DNA Barcoding of Two Gonioctena Species (Coleoptera: Chrysomelidae) Described from the Korean Peninsula

  • Cho, Hee-Wook;Kim, Sang Ki
    • Animal Systematics, Evolution and Diversity
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    • v.37 no.3
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    • pp.225-228
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    • 2021
  • Eleven Gonioctena species have been recorded in the Korean Peninsula. Most species in the genus have very similar coloration and morphology. The male genitalia is generally used as the only reliable diagnostic character differentiating closely related species, but it is still difficult to identify females to species accurately. Here, we determined the COI barcodes of two Gonioctena species described from Korea and give morphological descriptions. The interspecific genetic divergence (Kimura 2-parameter) among the Gonioctena ranged from 0.073 to 0.138 and averaged 0.108. The pairwise genetic distance between the two Korean species(0.102) is similar to the average interspecific divergence. We predict that these analyses will help to resolve taxonomic issues and find cryptic species.

Down-regulation of Protease-activated Receptor 4 in Lung Adenocarcinoma is Associated with a More Aggressive Phenotype

  • Jiang, Ping;Yu, Guo-Yu;Zhang, Yong;Xiang, Yang;Hua, Hai-Rong;Bian, Li;Wang, Chun-Yan;Lee, Wen-Hui;Zhang, Yun
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.6
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    • pp.3793-3798
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    • 2013
  • The role of protease-activated receptors (PARs) in lung tumors is controversial. Although PAR4 is preferentially expressed in human lung tissues, its possible significance in lung cancer has not been defined. The studies reported herein used a combination of clinical observations and molecular methods. Surgically resected lung adenocarcinomas and associated adjacent normal lung tissues were collected and BEAS-2B and NCI-H157 cell lines were grown in tissue culture. PAR4 expression was evaluated by RT-PCR, RT-qPCR, Western blotting and immunohistochemistry analysis. The results showed that PAR4 mRNA expression was generally decreased in lung adenocarcinoma tissues as compared with matched noncancerous tissues (67.7%) and was associated with poor differentiation (p=0.017) and metastasis (p=0.04). Western blotting and immunohistochemical analysis also showed that PAR4 protein levels were mostly decreased in lung adenocarcinoma tissues (61.3%), and were also associated with poor differentiation (p=0.035) and clinical stage (p=0.027). Moreover, PAR4 expression was decreased in NCI-H157 cells as compared with BEAS-2B cells. In conclusion, PAR4 expression is significantly decreased in lung adenocarcinoma, and down-regulation of PAR4 is associated with a more clinically aggressive phenotype. PAR4 may acts as a tumor suppressor in lung adenocarcinoma.

Alterations in Cellular and Plasma Membrane Glycopreteins in Chicken Myogenesis in Vitro (鷄胚의 細胞胞分化에 있어서 細胞 및 原形質膜 糖蛋白質의 變化)

  • Kang, Man-Sik;Song, Woo-Keun;Ho. Woo Nam;Chung, Chang-Yong
    • The Korean Journal of Zoology
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    • v.28 no.3
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    • pp.125-136
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    • 1985
  • The present study has been undertaken to elucidate whether there are developmentally regulated proteins in chick myogenesis by observing cellular and plasma membrane glycoproteins by use of labelled-Con A staining. At least three classes and five classes of glycoproteins can be identified in terms of their occurrence and their change in levels, respectively. As to the former, there are glycoproteins which are specific to cellular fraction are eight, those which are specific to plasma membrane are four, and those which occur in both fraction are nine. Likewise, as to the latter, there are glycoproteins which are invariant, those which increase in level, those which decrease, those which increase and subsequently decrease, and those which decrease and subsequently increase. The present experiment reveals that the level of fibronectin does decrease after the fusion and that the apparent conflicting results so far reported may be due to the difference in time point setting during fusion and myotube stages. It is thought to be a general tendency that glycoproteins of high-molecular-weight decrease and those of low-molecular-weight increase in relative levels as the fusion proceeds. These results are suggestive of the fact that a major structural reorganization of glycoproteins does occur in association with myoblast fusion.

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Biomass Conversion Efficiencies of Fish Pond Fertilization and Feed Supplementation

  • Mahboob, Shahid;Sheri, A.N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.2
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    • pp.192-195
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    • 1998
  • Biomass conversion efficiencies (B.C.E) of six fish species viz, Catla catla, Labeo, rohita, Cirrhina mrigala, Hypophthalmicthys molitrix, Ctenopharyngodon idella and Cyprinus carpio cultured under artificial feed (T1), broiler manure (T2), buffalo manure (T3), N:P:K (25:25:0) (T4) and control pond (T5) have been determined for the period of one year. The overall biomass conversion efficiencies under the influence of T2, T3, and T4 were statistically similar. However, the best (0.40) efficiency was determined under feed supplement-ation (T1).

Cellulolytic ability of Bacillus amyloliquefaciens in the gut of Reticulitermes speratus kyushuenesis Morimoto (Reticulitermes speratus kyushuenesis Morimoto의 장내세균 Bacillus amyloliquefaciens에 의한 Cellulose 분해 능력)

  • 박현철;배태웅
    • The Korean Journal of Soil Zoology
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    • v.3 no.2
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    • pp.51-57
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    • 1998
  • A new rod-shaped endospore-forming bacterium isolated from the hindgut flora of the termite, Reticulitermes speratus kyushuenesis Morimoto is described. The isolate stained Gram positive, but the KOH test and the test for L-alanine aminopeptidase were negative. The length of a single cell varies from 2.5-9.0 $\mu $m, and the cell is about 0.5-0.7$\mu $m thick. The isolate had a high cellulolytic ability and was identified as Bacillus amyloliquefaciens.

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