• 제목/요약/키워드: neural differentiation

검색결과 189건 처리시간 0.023초

체외수정 유래 생쥐 배아줄기세포와 유사한 특성을 보유한 단위발생 유래 생쥐 배아줄기세포 (Parthenogenetic Mouse Embryonic Stem Cells have Similar Characteristics to In Vitro Fertilization mES Cells)

  • 박세필;김은영;이금실;이영재;신현아;민현정;이훈택;정길생;임진호
    • Clinical and Experimental Reproductive Medicine
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    • 제29권2호
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    • pp.129-138
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    • 2002
  • Objective: This study was to compare the characteristics between parthenogenetic mES (P-mES) cells and in vitro fertilization mES cells. Materials and Methods: Mouse oocytes were recovered from superovulated 4 wks hybrid F1 (C57BL/6xCBA/N) female mice. For parthenogenetic activation, oocytes were treated with 7% ethanol for 5 min and $5{\mu}g$/ml cytochalasin-B for 4 h. For IVF, oocytes were inseminated with epididymal sperm of hybrid F1 male mice ($1{times}10^6/ml$). IVF and parthenogenetic embryos were cultured in M16 medium for 4 days. Cell number count of blastocysts in those two groups was taken by differential labelling using propidium iodide (red) and bisbenzimide (blue). To establish ES cells, b1astocysts in IVF and parthenogenetic groups were treated by immunosurgery and recovered inner cell mass (ICM) cells were cultured in LIF added ES culture medium. To identify ES cells, the surface markers alkaline phosphatase, SSEA-1, 3,4 and Oct4 staining were examined in rep1ated ICM colonies. Chromosome numbers in P-mES and mES were checked. Also, in vitro differentiation potential of P-mES and mES was examined. Results: Although the cleavage rate (${\geq}$2-cell) was not different between IVF (76.3%) and parthenogenetic group (67.0%), in vitro development rate was significantly low in parthenogenetic group (24.0%) than IVF group (68.4%) (p<0.05). Cell number count of ICM and total cell in parthenogenetic b1astocysts ($9.6{\pm}3.1,\;35.1{\pm}5.2$) were signficantly lower than those of IVF blastocysts ($19.5{\pm}4.7,\;63.2{\pm}13.0$) (p<0.05). Through the serial treatment procedure such as immunosurgery, plating of ICM and colony formation, two ICM colonies in IVF group (mES, 10.0%) and three ICM colonies (P-mES, 42.9%) in parthenogenetic group were able to culture for extended duration (25 and 20 passages, respectively). Using surface markers, alkaline phosphatase, SSEA-l and Oct4 in P-mES and mES colony were positively stained. The number of chromosome was normal in ES colony from two groups. Also, in vitro neural and cardiac cell differentiation derived from mES or P-mES cells was confirmed. Conclusion: This study suggested that P-mES cells can be successfully established and that those cell lines have similar characteristics to mES cells.

설계민감도 해석에서 역전파 방법을 사용한 응력제한조건 위상최적설계 (Stress Constraint Topology Optimization using Backpropagation Method in Design Sensitivity Analysis)

  • 김민근;김석찬;김재승;이재경;이근호
    • 한국전산구조공학회논문집
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    • 제35권6호
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    • pp.367-374
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    • 2022
  • 본 논문에서는 역전파 방법 기반 자동미분법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용하였다. 응력제한조건이 있는 위상최적화문제는 특이점(singularity)과 응력의 국부성(local nature of stress constraint)문제, 그리고 설계 변수에 대한 비선형성의 문제를 포함하고 최적해를 얻기가 매우 힘들다. 특이점 문제를 해결하기 위해서 응력 완화(stress relaxation) 기법을 사용하였고, 응력의 국부성을 해결하기 위해 p-norm을 이용한 전역 응력치를 제한조건에 사용하였다. 설계 변수에 대한 비선 형성을 극복하기 위해 해석적인 방법으로 정확한 설계민감도를 구하는 것이 중요하다. 위상최적설계에서 기존에는 보조변수방법 (adjoint variable method)을 사용하여 빠르고 정확한 설계민감도를 구했지만, 설계민감도를 해석적으로 구해야 하고, 보조평형방정식을 추가로 풀어야 하는 어려움이 있다. 이를 해결하기 위해서 인공신경망에서 최적 가중치(weights)와 편차(biases)를 구할 때 쓰이는 역전파 기법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용하였다. 역전파 기법은 자동미분에 쓰이는 기법으로 목적함수나 제한조건에 대한 설계민감도를 별도의 수식유도 없이 간단하게 구할 수 있는 장점이 있다. 또한, 미분값을 구하는 역전파의 과정이 보조평형방정식을 푸는 것보다 계산시간이 빠르고 해석적 방법으로 구한 설계민감도와 같은 정확도를 보여준다.

Erk와 retinoic acid의 제1인구둥 패터닝 조절 (Erk AND RETINOIC ACID SIGNALING PARTICIPATE IN THE SEGREGATION AND PATTERNING OF FIRST ARCH DERIVED MAXILLA AND MANDIBLE)

  • 박은주;탁혜진;박은하;백정미;;이상휘
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제31권2호
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    • pp.103-115
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    • 2009
  • In vertebrates, the face is mainly formed with neural crest derived neural crest cells by the inherent programs and the interactive environmental factors. Extracellular signaling-regulated kinase (Erk) is one of such programs to regulate the various cellular functions. And retinoic acid (RA) also plays an important role as a regulator in differentiation process at various stages of vertebrate embryogenesis. We wanted to know that the segregation as well as the patterning of maxillary and mandibular structure is greatly influenced by the maxillomandibular cleft (MMC) and the failure of this development may result in the maxillomandibular fusion (syngnathia) or other patterning related disorder. It has been well documented that the epithelium at this cleft region has significant expression of Fibroblast growth factor (Fgf) 8, and it is essential for the patterning of the first arch derived structures. By the morphological, skeletal, cell proliferation and apoptotic, and hybridization analysis, we checked the effects of Erk inhibition and/or RA activation onto MMC and could observe that Erk and RA signaling is individually and synergically involved in the facial patterning in terms of FGF signaling pathway via Barx-l. So RA and Erk signaling work together for the MMC patterning and the segregation of maxilla-mandible by controlling the Fgf-related signaling pathways. And the abnormality in MMC brought by aberrant Fgf signaling may result in the disturbances of maxillary-mandibular segregation.

외식프랜차이즈의 서비스 경험이 만족과 재방문의도에 미치는 영향: 인공신경망 분석의 적용 (Effect of Online Food Service Franchise Experiences on Satisfaction and Revisit Intention: Application of ANN Analysis)

  • 이신화;안성만;이유정
    • 한국프랜차이즈경영연구
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    • 제10권2호
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    • pp.59-70
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    • 2019
  • Purpose - Every company studies how to attract and retain new customers to increase competitiveness and profitability. Companies establish strategies to attract customers, secure competitive advantage and generate revenue. Businesses are looking for newer and better ways to differentiate themselves in the marketplace. One of the requirements for service differentiation is to make it a prerequisite for an engaging customer experience. Customer experience can be attained through service experience. Satisfaction determine whether to reuse the food service franchise. The purpose of this study is to investigate the effect of customer experience on the satisfaction and revisit intention of food service franchise. In this study, customer experience consists of three attributes such as service environment, food quality, and price fairness. Also, this study is to identify the importance of three service experience attributes of customer satisfaction and revisit intention using ANN (artificial neural network) analysis. Research design, data, methodology - The survey was conducted on customers who have visited franchise restaurants in one month in order to examine how service environment, food quality, and price fairness have been influenced customer satisfaction and revisit intention through online survey company (SM culture & contents). A total of 300 representative surveys were collected. Of those collected surveys, 26 were not used due to missing information, resulting in 274 as the final sample size. The sample size was more than 10 times more than the number of variables used in the structural model analysis. Results - The findings of this study are as follows: Service environment and price fairness have a significant effect on satisfaction. However, food quality did not have a significant effect on satisfaction. Finally, it was found that satisfaction had a significant effect on revisit intention. Meanwhile, according to the results of ANN analysis, satisfaction as a dependent variable was found to be the most important in male price fairness and service environment in female. Also, when the revisit intention is used as a dependent variable, both male and female price fairness are important. Also, when the intention to revisit is used as a dependent variable, both male and female price processes are important. Conclusions - First, a restaurant franchise enterprise needs to manage customer service experience. Customers should strive to eat and enjoy at a dining franchise store. Second, it is necessary to design a food service franchise shop as a customer-oriented service environment. Franchise companies need to improve the environment so that customers can use the store conveniently. Third, the restaurant franchise menu price needs to be cheaper than the alternative menu. The restaurant franchise menu needs to be constructed with a popular menu that can be used continuously by the customer, so that it can be set at a reasonable price.

우울증에 관한 Sirtuin 1의 역할과 관련된 기전 (Role of Sirtuin 1 in Depression and Associated Mechanisms)

  • 석대현;박성우
    • 생명과학회지
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    • 제31권12호
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    • pp.1120-1127
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    • 2021
  • 우울증은 높은 유병률과 자살률 증가로 인해 사회적 기능에 부정적인 영향을 미치며, 경제적 부담 또한 높은 질환이다. 우울증은 신경염증, 시냅스 기능장애, 인지 결손과 같은 뇌에서 다양한 현상과 관련이 있다. 임상에서 사용되는 항우울제들은 치료효과가 낮아 빠른 효능을 보이는 항우울제 개발이 시급하다. 현재까지 우울증과 관련된 다양한 유전자, 단백질, 그리고 신호전달계에 대한 많은 연구가 수행되었지만, 우울증의 발생기전은 명확하게 밝혀지지 않았다. Sirtuin 1은 nicotinamide-adenine dinucleotid- (NAD+-) dependent histone deacetylases로써 세포 분화, 세포 사멸, 발생, 자가소화작용, 암 대사에 관여하는 것으로 알려져 있다. 최근의 유전연구들은 Sirtuin 1이 우울증의 잠재적 타겟 유전자라고 제안하고 있다. 또한 전임상 연구에서는 Sirtuin 1의 신호전달기전이 우울행동에 영향을 미친다고 보고 하였다. 본 종설에서는 우울증과 Sirtuin 1에 대한 최신 지식을 제시하였다. 소교세포의 활성, 일주기 생체 리듬, 신경세포 생성, 및 인지기능의 조절에 관여하는 Sirtuin 1이 우울증에 미치는 다양한 영향을 설명하였다. 아울러 Sirtuin 1이 우울증 핵심 기전중의 하나인 신경가소성의 손상에 미치는 영향과 그 기전에 대해서 논의하였다.

Differential Expression of NCAM-180 in the Olfactory System and Retina of the Rat

  • Hyeyoung Koo
    • Animal cells and systems
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    • 제3권3호
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    • pp.259-267
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    • 1999
  • The expression of the neural cell adhesion molecule-180 (NCAM-180), which accumulates at contact sites between cells and may be responsible for the stabilization of cell contacts, was studied in the olfactory system and retina of developing and adult rats. From embryonic day 12 onwards, which was the earliest stage examined, the NCAM-180 pathway directing to the presumptive olfactory bulb was observed. In later stages, olfactory neurons and fasciculating axons in the olfactory epithelium and nerve fiber layer and glomeruli of the olfactory bulb expressed NCAM-180. From postnatal day 0, immunolabelling pattern of the olfactory epithelium and olfactory bulb were the same as that during later stages. NCAM-180 immunoreactivity was present on differentiating retinal cells and persisted on those cells throughout adulthood. However, contrary to the olfactory nerve which remained detectable in the adult, the optic nerve was only transiently expressed with NCAM-180 and was no longer detectable in the adult. The presence of NCAM-180 in olfactory tissues suggests their possible role in pathfinding, differentiation, fasciculation and synaptic plasticity. The continued presence of NCAM-180 in the olfactory system examined may underlie its continuous cell turnover and regenerative capacity. The continuous expression of NCAM-180 in ganglion cells, bipolar cells and photoreceptor cells, also suggests potential regenerating capability and some plastic functions for these cells in the adult. Since the expression of NCAM-180 by the optic nerve was restricted to the period of special histogenetic events, for example, during axonal growth and synaptogenesis, it is possible that the lack of NCAM-180 in the adult optic nerve might cause a nonpermissive environment for the regeneration and result in regenerative failure of this system.

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임신일령에 따른 생쥐 태아 뇌조직의 단백질 발현 양상 분석 (Analysis of brain protein expression in developing mouse fetus)

  • 한영훈;김홍래;조운비;우제석;진동일
    • 농업과학연구
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    • 제38권1호
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    • pp.65-70
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    • 2011
  • Development of mouse fetus brains can be defined morphologically and functionally by three developmental stages, embryo day (ED) 16, postnatal stage one week and eight weeks. These defined stages of brain development may be closely associated with differential gene expression rates due to limited cellular resources such as energy, space, and free water. Complex patterns of expressed genes and proteins during brain development suggests the changes in relative concentrations of proteins rather than the increase in numbers of new gene products. This study was designed to evaluate early protein expression pattern in mouse fetus brain. The mouse brain proteome of fetus at ED 15.5, and 19.5 was obtained using 2-dimensional gel electrophoresis (DE). Analysis of the 2-DE gels in pH 3-10 range revealed the presence of 15 differentially expressed spots, of which 11 spots were identified to be known proteins following MALDI-TOF analysis; 3 spots were up-regulated and 8 spots were down-regulated in the mouse fetus brain at ED 15.5. UP-regulated proteins were identified as MCG18238, isoform M2 of pyruvate kinase isozymes M1/M2, isoform 2 of heterogeneous nuclear ribonucleoprotein K, heterogeneous nuclear ribonucleoprotein H2, creatine kinase B-type, 40S ribosomal protein SA and hemoglobin subunit beta-H1. Down-regulated proteins were putative uncharacterized protein, lactoylglutathione lyase and secreted acidic cysteine rich glycoprotein. Our results revealed composite profiles of mouse fetus brain proteins related to mouse fetus development by 2-DE analysis implying possible roles of these proteins in neural differentiation.

치근단질환에서 형질전환성장인자-β와 기질금속함유단백분해효소 발현에 관한 연구 (A STUDY ON THE EXPRESSION OF TRANSFORMING GRO WITH FACTOR-β AND MATRIX METALLOPROTEINASE-1 IN PERIAPICAL LESION)

  • 지정호;이수종
    • Restorative Dentistry and Endodontics
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    • 제24권1호
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    • pp.200-211
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    • 1999
  • The periapical response to injury is a complex interaction of inflammatory, immune, neural, vascular and synthetic activity. TGF-${\beta}$ is a potent modulator of proliferation and differentiation in various tissue, seems to lead to an increase in extracellular matrix. MMP are a family of proteolytic enzyme that mediate the degradation of extracellular matric macromolecules, but little is known about theirs possible role in periapical tissue. The purpose of this study is to investigate the differential expression of TGF-${\beta}$ and MMP-1 in tooth follicle, periapical abscess, granuloma and cyst. The expression of TGF-${\beta}$ and MMP-1 in Periapical tissue was evaluated by immunohistochemical staining and Western blot analysis. Correlationship among the periapical lesions were stastically analyzed. The degree of MMP-1 expression in periapical abscess was higher than in any other periapical lesion, and stastically significant. TGF-${\beta}$ expression is the prominent in granuloma than other periapical lesion, which was stastically significant. The increased expression of MMP and TGF-${\beta}$ was not co-related with inflammatory cell infiltration degree of the periapical cyst. The expression degree of MMP and TGF-${\beta}$ was not co-related with periapical abscess and cyst, but expression of MMP and TGF-${\beta}$ showed strong positive co-relationship with periapical granuloma, which was stastically significant. TGF-${\beta}$ expression by Western blot analysis was prominent in granuloma and cyst, and similar to the results by imunohistochemistry. MMP-1 expression is less than TGF-${\beta}$, but there is not extreme difference between periapical lesion. These results suggest that TGF-${\beta}$ and MMP may be involved in tissue remodeling and has an important role in progress or mediation of periapical lesions.

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구강편평상피암종에서 DCC 유전자의 역할 (ROLE OF DCC(DELETED IN COLORECTAL CANCER) GENE IN ORAL SQUAMOUS CELL CARCINOMA)

  • 고성규;한세진;김경욱
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제34권5호
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    • pp.518-524
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    • 2008
  • Chromosome 18q alteration plays a key role in colorectal tumorigenesis, and loss of heterozygosity at 18q is associated with a poor prognosis in colon cancer. DCC(Deleted in Colorectal Cancer) is a putative tumor- suppressor gene at 18q21 that encodes a transmembrane protein with structural similarity to neural cell adhesion molecule that is involved in both epithelial and neuronal cell differentiation. DCC is implicated in regulation of cell growth, survival and proliferation. Thus, tumor progression in squamous cell carcinoma, stomach cancer, colorectal cancer correlates with downregulation of DCC expression. The mechanism for DCC suppression is associated with hypermethylation of the DCC gene promoter region. Hence, the goal of this study is to identify the promoter methylation responsible for the down-regulation of DCC expression in oral squamous cell carcinoma. 12 of tissue specimens for the study are excised and gathered from 12 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find expression of DCC in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1. In the DCC gene RT-PCR analysis, 5(41.6%) of 12 specimens of oral squamous cell carcinoma did not expressed DCC gene. 2. In the promoter methylation specific PCR analysis, 5(41.6%) of 12 specimens showed promoter methylation of DCC gene. 3. In the immunohistochemical staining of poor differentiated and invasive oral squamous cell carcinoma, loss of DCC expression was observed. These findings suggest that methylation of the DCC gene may play a role in loss of gene expression in invasive oral squamous cell carcinoma.

Urological Evaluation of Tethered Cord Syndrome

  • Park, Kwanjin
    • Journal of Korean Neurosurgical Society
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    • 제63권3호
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    • pp.358-365
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    • 2020
  • To describe how to perform urological evaluation in children with tethered cord syndrome (TCS). Although a common manifestation of TCS is the development of neurogenic bladder in developing children, neurosurgeons often face difficulty in detecting urological problems in patients with TCS. From a urological perspective, diagnosis of TCS in developing children is further complicated due to the differentiation between neurogenic bladder dysfunctions and transient bladder dysfunctions owing to developmental problems. Due to the paucity of evidence regarding evaluation prior to and after untethering, I have shown the purpose and tools for evaluation in my own practice. This may be tailored to the types of neurogenic bladder, developmental status, and risks for deterioration. While the urodynamic study (UDS) is the gold standard test for understanding bladder function, it is not a panacea in revealing the nature of bladder dysfunction. In addition, clinicians should consider the influence of developmental processes on bladder function. Before untethering, UDS should reveal synergic urethral movement, which indicates an intact sacral reflex and lack of TCS. Postoperatively, the measurement of post-void residual urine volume is a key factor for the evaluation of spontaneous voiders. In case of elevation, fecal impaction, which is common in spinal dysraphism, should be addressed. In patients with clean intermittent catheterization, the frequency-volume chart should be monitored to assess the storage function of the bladder. Toilet training is an important sign of maturation, and its achievement should be monitored. Signs of bladder deterioration should be acknowledged, and follow-up schedule should be tailored to prevent upper urinary tract damage and also to determine an adequate timing for intervention. Neurosurgeons should be aware of urological problems related to TCS as well as urologists. Cooperation and regular discussion between the two disciplines could enhance the quality of patient care. Accumulation of experience will improve follow-up strategies.