• 제목/요약/키워드: Roles in reproduction

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사회자본과 문화자본 형성 기제로서의 공공도서관의 역할 (The Roles of Public Libraries as a Construction Mechanism of Social and Cultural Capital)

  • 이승민
    • 한국비블리아학회지
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    • 제29권4호
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    • pp.139-160
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    • 2018
  • 본 연구는 사회자본과 문화자본의 형성 및 이들 사이의 연계, 그리고 이들 자본이 재생산하는 사회적 계급의 해소를 위해 공공도서관이 어떠한 역할을 미치는지를 확인하는데 목적을 두고 있다. 이를 위해 공공도서관 이용자를 대상으로 사회자본, 문화자본 및 공공도서관 이용과 관련한 설문조사를 수행하였다. 분석 결과, 공공도서관의 이용은 사회자본과 문화자본의 형성에 전반적으로 긍정적인 영향을 미치는 것으로 분석되었다. 하지만 학력수준과 소득수준이 높은 계급일수록 공공도서관의 이용이 높게 나타나고 있어, 공공도서관의 이용이 사회자본과 문화자본으로 인한 사회적 계급화의 해소에는 부분적인 영향만을 미치는 것으로 나타났다. 따라서 공공도서관이 사회자본과 문화자본의 평등한 형성에 기여하기 위해서는 개방된 사회적 교류의 장으로서의 역할을 수행할 필요가 있으며, 다양한 문화자원에 대한 접근 및 이를 활용할 수 있는 기회를 제공하는 기능이 보다 활성화될 필요가 있다.

Potency of Melatonin in Living Beings

  • Choi, Donchan
    • 한국발생생물학회지:발생과생식
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    • 제17권3호
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    • pp.149-177
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    • 2013
  • Living beings are surrounded by various changes exhibiting periodical rhythms in environment. The environmental changes are imprinted in organisms in various pattern. The phenomena are believed to match the external signal with organisms in order to increase their survival rate. The signals are categorized into circadian, seasonal, and annual cycles. Among the cycles, the circadian rhythm is regarded as the most important factor because its periodicity is in harmony with the levels of melatonin secreted from pineal gland. Melatonin is produced by the absence of light and its presence displays darkness. Melatonin plays various roles in creatures. Therefore, this review is to introduce the diverse potential ability of melatonin in manifold aspects in living organism.

Leptin in Chickens - a Review

  • Choi, Yang-Ho
    • 한국가금학회:학술대회논문집
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    • 한국가금학회 2005년도 제22차 정기총회 및 학술발표회
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    • pp.8-16
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    • 2005
  • 비만유전자의 산물인 렙틴은 주로 지방세포에서 생성 분비된다. 렙틴은 뇌 시상하부에 작용하여 식이섭취량을 줄이고 에너지발산을 증가시켜 궁극적으로 체중을 감소시킨다. 따라서 렙틴 또는 렙틴 수용체의 이상은 극도의 대사증후군을 유발한다. 현재까지 렙틴에 관한 연구의 대부분은 사람을 포함한 포유류에서 수행되었다. 렙틴의 생리적 작용은 만복인자뿐만이 아니다. 본고에서는 현재까지 발표된 논문을 중심으로 닭에서 식이섭취, 면역, 지방대사, 번식과 발달, 그리고 스트레스에 관한 렙틴의작용을 검토했다.

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노랑초파리 발생과정에서의 ultraspiracle 유전자 산물의 발현 (The Expression of ultraspiracle Gene Product during Development of Drosophisa melanogaster)

  • 김세재;정기화이정주
    • 한국동물학회지
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    • 제38권2호
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    • pp.220-229
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    • 1995
  • uftraspirocle (usa) gene product (Uspl is a member of the superfamilv of steroid hormone receptors in Drosophila melonogaster which mediate the hormone action by heteromerization with ecdvsone receptor (EcR). Based on the genetic and molecular characterization of usp, it has been proposed that Usp funtions in at least three significant developmental pathway: embrvogenesis, eve morphogenesis, and female reproduction. In this study, the expression patterns of Usp were investigated by immunohistochemistrv in individual tissues from diHernt developmental stases of Drosophila. Usp is localized in the nucleus with ubiquitous distribution throughout development. Usp expression is detected throughout embrvogenesis. Usp is expressed in imaginal and lanral tissues from late third instar 18nra. The expression pattern of Usp is overlapped by those of EcR. Also Usp is expressed in differentiating adult reproductive organs. This result suggests that Usp is not a transcriptional regulatory factor modulating hormonal response during development, but also play some roles in female and male reproduction of Drosophila.

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Polyunsaturated Fatty Acids in Male Ruminant Reproduction - A Review

  • Tran, Len Van;Malla, Bilal Ahmad;Kumar, Sachin;Tyagi, Amrish Kumar
    • Asian-Australasian Journal of Animal Sciences
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    • 제30권5호
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    • pp.622-637
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    • 2017
  • Fatty acids such as n-3 and n-6 polyunsaturated fatty acids (PUFA) are critical nutrients, used to improve male reproductive performance through modification of fatty acid profile and maintenance of sperm membrane integrity, especially under cold shock or cryopreservation condition. Also, PUFA provide the precursors for prostaglandin synthesis and can modulate the expression patterns of many key enzymes involved in both prostaglandin and steroid metabolism. Many studies carried out on diets supplemented with PUFA have demonstrated their capability to sustain sperm motility, viability and fertility during chilling and freezing as well as improving testis development and spermatogenesis in a variety of livestock species. In addition to the type and quantity of dietary fatty acids, ways of addition of PUFA to diet or semen extender is very crucial as it has different effects on semen quality in male ruminants. Limitation of PUFA added to ruminant ration is due to biohydrogenation by rumen microorganisms, which causes conversion of unsaturated fatty acids to saturated fatty acids, leading to loss of PUFA quantity. Thus, many strategies for protecting PUFA from biohydrogenation in rumen have been developed over the years. This paper reviews four aspects of PUFA in light of previous research including rumen metabolism, biological roles, influence on reproduction, and strategies to use in male ruminants.

The role of hepatic stellate cells in fibrotic liver diseases

  • Cho, Hye Jin;Jang, Jae Young;Kim, Tae Min
    • 한국동물생명공학회지
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    • 제35권2호
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    • pp.113-118
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    • 2020
  • Hepatic stellate cells (HSCs) play essential roles in normal and pathophysiological function in liver. In steady state, HSCs contribute to retinoid storage, immune tolerance, and extracellular matrix (ECM) homeostasis. Upon liver injury, they become activated and lead to morphological and functional changes. Studies have demonstrated that activation of HSCs by various stimuli such as toxins, microbial infection, or metabolic overload can promote the fibrotic changes in liver by production of ECM. Herein, we provide current knowledge about the basic characteristics of HSCs and the mechanism by which they are activated.

The Ascidian Numb Gene Involves in the Formation of Neural Tissues

  • Ahn, Hong Ryul;Kim, Gil Jung
    • 한국발생생물학회지:발생과생식
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    • 제16권4호
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    • pp.371-378
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    • 2012
  • Notch signaling plays fundamental roles in various animal development. It has been suggested that Hr-Notch, a Notch homologue in the ascidian Halocynthia roretzi, is involved in the formation of peripheral neurons by suppressing the neural fates and promoting the epidermal differentiation. However, roles of Notch signaling remain controversial in the formation of nervous system in ascidian embryos. To precisely investigate functions of Notch signaling, we have isolated and characterized Hr-Numb, a Numb homologue which is a negative regulator of Notch signaling, in H. roretzi. Maternal expression of Hr-Numb mRNAs was detected in egg cytoplasm and the transcripts were inherited by the animal blastomeres. Its zygotic expression became evident by the early neurula stage and the transcripts were detected in dorsal neural precursor cells. Suppression of Hr-Numb function by an antisense morpholino oligonucleotide resulted in larvae with defect in brain vesicle and palps formation. Similar results have been obtained by overexpression of the constitutively activated Hr-Notch forms. Therefore, these results suggest that Hr-Numb is involved in Notch signaling during ascidian embryogenesis.

Conserved Roles of MonA in Fungal Growth and Development in Aspergillus Species

  • Son, Ye-Eun;Park, Hee-Soo
    • Mycobiology
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    • 제47권4호
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    • pp.457-465
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    • 2019
  • MonA is a subunit of a guanine nucleotide exchange factor that is important for vacuole passing and autophagy processes in eukaryotes. In this study, we characterized the function of MonA, an orthologue of Saccharomyces cerevisiae Mon1, in the model fungus Aspergillus nidulans and a toxigenic fungus A. flavus. In A. nidulans, the absence of AnimonA led to decreased fungal growth, reduced asexual reproduction, and defective cleistothecia production. In addition, AnimonA deletion mutants exhibited decreased spore viability, had reduced trehalose contents in conidia, and were sensitive to thermal stress. In A. flavus, deletion of AflmonA caused decreased fungal growth and defective production of asexual spores and sclerotia structures. Moreover, the absence of monA affected vacuole morphology in both species. Taken together, these results indicate that MonA plays conserved roles in controlling fungal growth, development and vacuole morphology in A. nidulans and A. flavus.

Expression and Function of CTNNB1 in the Development of Avian Reproductive System

  • Bae, Seung-Min;Song, Gwonhwa
    • Reproductive and Developmental Biology
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    • 제38권1호
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    • pp.35-40
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    • 2014
  • Beta-catenin (CTNNB1, catenin (cadherin-associated protein), beta 1) is involved in various biological processes, including embryogenesis, tumorigenesis, angiogenesis and progression of metastasis. CTNNB1, as a multifunctional and oncogenic protein, has important roles in adhesion between Sertoli cells through an N-cadherin-dependent manner and in various cancer types through its over-activation. In addition, CTNNB1 can interact with estrogen/estrogen receptor alpha complex, which regulates the transcription of WNT (wingless-type MMTV integration site family)/CTNNB1 target genes. Recently, we investigated the functional roles and expression pattern of CTNNB1 during the morphological changes of embryonic gonads of chickens and the estrogen-dependent regulation of CTNNB1 in oviduct development and potential functions as a biomarker of CTNNB1 in human epithelial ovarian cancer using the chicken as a biological research model. Therefore, in this review, we provide a new insight of potential role of CTNNB1 in the development of the female reproductive tract during early embryogenesis and ovarian carcinogenesis of laying hen models.

Biological roles of NAC transcription factors in the regulation of biotic and abiotic stress responses in solanaceous crops

  • Tweneboah, Solomon;Oh, Sang-Keun
    • Journal of Plant Biotechnology
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    • 제44권1호
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    • pp.1-11
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    • 2017
  • Evolutionary studies conducted on NAC (NAM, ATAF1&2, and CUC2) genes for all major groups of land plants, indicate the presence of the NAC subfamilies, even in the early land plants. The varied roles played by NAC proteins in plant growth and development range from the formation of shoot apical meristem, floral organ development, reproduction, lateral shoot development, and defense responses to biotic and abiotic stresses. Considering the value and importance of solanaceous crops, the study of NAC proteins in these plants needs to be intensified. This will help to identify and functionally characterize their promoters, which will subsequently aid in engineering plants with improved performance under stressful conditions. In this review, the functionally characterized NAC transcription factors specific to tomato, potato, tobacco, chili pepper and eggplant (aubergine) are summarized, clearly indicating their biological functions in the defense mechanism of the plants, against biotic and abiotic stresses.