• Title/Summary/Keyword: Stress Function

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Molecular characterization and expression of suppressor of cytokine signaling (SOCS) 1, 2 and 3 under acute hypoxia and reoxygenation in pufferfish, Takifugu fasciatus

  • Wang, Dan;Wen, Xin;Zhang, Xinyu;Hu, Yadong;Li, Xinru;Zhu, Wenxu;Wang, Tao;Yin, Shaowu
    • Genes and Genomics
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    • v.40 no.11
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    • pp.1225-1235
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    • 2018
  • Hypoxia seriously affects the innate immune system of fish. However, the roles of suppressor of cytokine signaling (SOCS), pivotal anti-inflammatory genes, in response to hypoxia/reoxygenation remain largely unexplored. The primary objective of this study was to elucidate the function of SOCS genes under acute hypoxia and reoxygenation in pufferfish (Takifugu fasciatus). In the present study, SOCS1, 2 and 3 were identified in T. fasciatus referred to as TfSOCS1, 2 and 3. Then, qRT-PCR and western blot analysis were employed to assess their expressions at both the mRNA and protein levels. Tissue distribution demonstrated that the three SOCS genes were predominantly distributed in gill, brain and liver. Under hypoxia challenge ($1.63{\pm}0.2mg/L$ DO for 2, 4, 6 and 8 h), the expressions of TfSOCS1 and 3 in brain and liver at the mRNA and protein levels were significantly decreased, while their expressions showed an opposite trend in gill. Different from the expressions of TfSOCS1 and 3, the expression of TfSOCS2 was inhibited in gill, along with its increased expression in brain and liver. After normoxic recovery ($7.0{\pm}0.3mg/L$ of DO for 4 and 12 h), most of TfSOCS genes were significantly altered at R4 (reoxygenation for 4 h) and returned to the normal level at R12 (reoxygenation for 12 h). SOCS genes played vital roles in response to hypoxia/reoxygenation challenge. Our findings greatly strengthened the relation between innate immune and hypoxia stress in T. fasciatus.

Dynamic Analysis of MLS Difference Method using First Order Differential Approximation (1차 미분 근사를 이용한 MLS차분법의 동적해석)

  • Kim, Kyeong-Hwan;Yoon, Young-Cheol;Lee, Sang-Ho
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.31 no.6
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    • pp.331-337
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    • 2018
  • This paper presents dynamic algorithm of the MLS(moving least squares) difference method using first order differential Approximation. The governing equations are only discretized by the first order MLS derivative approximation. The system equation consists of an assembly of the approximate function, so the shape of system equation is similar to FEM(finite element method). The CDM(central difference method) is used for time integration of dynamic equilibrium equation. The natural frequency analyses of the MLS difference method and FEM are performed, and two analysis results are compared. Also, the accuracy of the proposed numerical method is verified by displaying the dynamic analysis results together with the results by the existing second order differential approximation. In the process of assembling the first order MLS derivative approximation, the oscillation error was suppressed and the stress distribution was interpreted as relatively uniform.

Lactobacillus casei Zhang Prevents Jejunal Epithelial Damage to Early-Weaned Piglets Induced by Escherichia coli K88 via Regulation of Intestinal Mucosal Integrity, Tight Junction Proteins and Immune Factor Expression

  • Wang, Yuying;Yan, Xue;Zhang, Weiwei;Liu, Yuanyuan;Han, Deping;Teng, Kedao;Ma, Yunfei
    • Journal of Microbiology and Biotechnology
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    • v.29 no.6
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    • pp.863-876
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    • 2019
  • Farm animals such as piglets are often affected by environmental stress, which can disturb the gut ecosystem. Antibiotics were commonly used to prevent diarrhea in weaned piglets, but this was banned by the European Union due to the development of antibiotic resistance. However, the use of probiotics instead of antibiotics may reduce the risk posed by pathogenic microorganisms and reduce the incidence of gastrointestinal diseases. Therefore, this study was conducted to investigate the effects of Lactobacillus casei Zhang on the mechanical barrier and immune function of early-weaned piglets infected using Escherichia coli K88 based on histomorphology and immunology. Fourteen-day-old weaned piglets were divided into a control group and experimental groups that were fed L. casei Zhang and infected with E. coli K88 with or without prefeeding and/or postfeeding of L. casei Zhang. The L. casei Zhang dose used was $10^7CFU/g$ diet. Jejunum segments were obtained before histological, immunohistochemical, and western blot analyses were performed. In addition, the relative mRNA expression of toll receptors and cytokines was measured. Piglets fed L. casei Zhang showed significantly increased jejunum villus height, villus height-crypt depth ratio, muscle thickness, and expression of proliferating cell nuclear antigen and tight junction proteins ZO-1 and occludin. The use of L. casei Zhang effectively reduced intestinal inflammation after infection. We found that L. casei Zhang feeding prevented the jejunum damage induced by E. coli K88, suggesting that it may be a potential alternative to antibiotics for preventing diarrhea in early-weaned piglets.

A study on the ultra precision machining of free-form molds for advanced head-up display device (첨단 헤드업 디스플레이 장치용 비구면 자유형상 금형의 초정밀 가공에 관한 연구)

  • Park, Young-Durk;Jang, Taesuk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.1
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    • pp.290-296
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    • 2019
  • Head-up displays for vehicles play an important role in displaying various information about the safety and convenience of driving on the windshield of the vehicle. In this study, ultra-precision machining was performed and evaluated as a method for machining a large-area aspheric free-form mirror that is applicable to augmented reality technology. Precision diamond cutting is highly accurate and suitable for the production of advanced parts with excellent surface integrity, low surface roughness, and low residual stress. By using an aspheric free-form mold, it is possible to improve the optical transfer function, reduce the distortion path, and realize a special image field curvature. To make such a mold, the diamond cutting method was used, and the result was evaluated using an aspherical shape-measuring machine. As a result, it was possible to the mold with shape accuracy (PV) below $1{\mu}m$ and surface roughness (Ra) below $0.02{\mu}m$.

OCT4B Isoform Promotes Anchorage-Independent Growth of Glioblastoma Cells

  • Choi, Sang-Hun;Kim, Jun-Kyum;Jeon, Hee-Young;Eun, Kiyoung;Kim, Hyunggee
    • Molecules and Cells
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    • v.42 no.2
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    • pp.135-142
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    • 2019
  • OCT4, also known as POU5F1 (POU domain class 5 transcription factor 1), is a transcription factor that acts as a master regulator of pluripotency in embryonic stem cells and is one of the reprogramming factors required for generating induced pluripotent stem cells. The human OCT4 encodes three isoforms, OCT4A, OCT4B, and OCT4B1, which are generated by alternative splicing. Currently, the functions and expression patterns of OCT4B remain largely unknown in malignancies, especially in human glioblastomas. Here, we demonstrated the function of OCT4B in human glioblastomas. Among the isoform of OCT4B, OCT4B-190 ($OCT4B^{19kDa}$) was highly expressed in human glioblastoma stem cells and glioblastoma cells and was mainly detected in the cytoplasm rather than the nucleus. Overexpression of $OCT4B^{19kDa}$ promoted colony formation of glioblastoma cells when grown in soft agar culture conditions. Clinical data analysis revealed that patients with gliomas that expressed OCT4B at high levels had a poorer prognosis than patients with gliomas that expressed OCT4B at low levels. Thus, $OCT4B^{19kDa}$ may play a crucial role in regulating cancer cell survival and adaption in a rigid environment.

From Gut to Brain: Alteration in Inflammation Markers in the Brain of Dextran Sodium Sulfate-induced Colitis Model Mice

  • Do, Jongho;Woo, Jungmin
    • Clinical Psychopharmacology and Neuroscience
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    • v.16 no.4
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    • pp.422-433
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    • 2018
  • Objective: Neuropsychiatric manifestations like depression and cognitive dysfunction commonly occur in inflammatory bowel disease (IBD). In the context of the brain-gut axis model, colitis can lead to alteration of brain function in a bottom-up manner. Here, the changes in the response of the hypothalamic-pituitary-adrenal axis and inflammation-related markers in the brain in colitis were studied. Methods: Dextran sodium sulfate (DSS) was used to generate a mouse model of colitis. Mice were treated with DSS for 3 or 7 days and sacrificed. We analyzed the gene expression of brain-derived neurotrophic factor (BDNF), cyclooxygenase 2 (COX-2), and glial fibrillary acidic protein (GFAP), and the expression of GFAP, in the hippocampus, hypothalamus, and amygdala. Additionally, the levels of C-reactive protein (CRP) and serum cortisol/corticosterone were measured. Results: Alteration of inflammatory-related markers varied depending on the brain region and exposure time. In the hippocampus, COX-2 mRNA, GFAP mRNA, and GFAP expression were upregulated during exposure to DSS. However, in the hypothalamus, COX-2 mRNA was upregulated only 3 days after treatment. In the amygdala, BDNF and COX-2 mRNAs were downregulated. CRP and corticosterone expression increased with DSS treatment at day 7. Conclusion: IBD could lead to neuroinflammation in a bottom-up manner, and this effect varied according to brain region. Stress-related hormones and serum inflammatory markers, such as CRP, were upregulated from the third day of DSS treatment. Therefore, early and active intervention is required to prevent psychological and behavioral changes caused by IBD, and region-specific studies can help understand the precise mechanisms by which IBD affects the brain.

Dynamic Shear Behaviors on the Normally Consolidation Clay-Geosynthetic Interface (토목섬유-정규압밀점토의 접촉면 동적 전단거동 평가)

  • Bae, Hyogon;Jang, Dongin;Kwak, Changwon;Park, Innjoon
    • Journal of the Korean GEO-environmental Society
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    • v.19 no.12
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    • pp.33-39
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    • 2018
  • In this study, important characteristics were identified for the Geosynthetic-soil interface using overburden pressure and saltwater and fresh water to evaluate silt shear behavior of the Geosynthetic-soil interface. In addition, waste landfill can secure spaces for waste disposal in the sea and this spaces can be used for additional facilities which will be necessary in the future. Analysis of behavior characteristics on interface of Geosynthetic-soil shows that, if analyzed using standard consolidometers, the consolidation stress of fresh water increased significantly more than saltwater. When analyzed using cyclic shear apparatus, saltwater and freshwater in both conditions, the displacement value increases as the wire gauges become closer to the lower module, and the shear fracture tends to occur radically under saltwater conditions than fresh water. Therefore, seawater, fresh water that act on the interface of geosynthetic-soil, and installation of facility using geosynthetic should be considered as important parameters that are essential for the dynamic design factor of the water controlling facility.

Meditation for Alzheimer's Disease: Systematic Review and Meta-Analysis

  • Lee, Go eun;Kim, Sang ho;Jung, In chul;Kang, Hyung won
    • Journal of Oriental Neuropsychiatry
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    • v.30 no.3
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    • pp.237-249
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    • 2019
  • Objectives: Interest in the use of complementary and alternative treatments to treat dementia. Meditation is used to treat various symptoms of physical and psychological diseases. Some studies suggest that meditation might have positive effects on cognitive functions, especially attention, in the elderly. However, how meditation affects Alzheimer's disease (AD) patients remains unclear. In this review, we assessed the effectiveness of practicing meditation in combination with standard care in AD. Methods: We searched the CCRCT, MEDLINE, EMBASE, AMED and CINAHL databases on 30 May 2017. We included randomized controlled trials (RCTs) that used meditation in adult patients diagnosed with AD. We allocated patients to a meditation combined with standard care or a standard care-only group. Results: The two RCTs met the inclusion criteria. A total of 98 patients were included in the meditation with standard care and standard care-only groups in this review. All meditation programs in the included trials were based on practicing mindfulness. The results of our meta-analysis indicatedthat adjunctive mindfulness meditation programs exerted favourable but non-significant effects on cognitive function on the Mini Mental State Examination (MMSE) (MD=4.68, 95% CI -0.11 to 9.46; Z=1.92, p=0.06). Only one study assessed depression, anxiety, quality of life and stress. No adverse events related to meditation were reported in the included studies. Conclusions: Insufficient data iscurrently available to determine the effectiveness of practicing meditation on patients diagnosed with AD. Hence, further RCTs with high methodological quality and larger sample sizes are needed to effectively estimate the effects of meditation on AD.

siRNAs Derived from Cymbidium Mosaic Virus and Odontoglossum Ringspot Virus Down-modulated the Expression Levels of Endogenous Genes in Phalaenopsis equestris

  • Lan, Han-hong;Wang, Cui-mei;Chen, Shuang-shuang;Zheng, Jian-ying
    • The Plant Pathology Journal
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    • v.35 no.5
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    • pp.508-520
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    • 2019
  • Interplay between Cymbidium mosaic virus (CymMV)/Odontoglossum ringspot virus (ORSV) and its host plant Phalaenopsis equestris remain largely unknown, which led to deficiency of effective measures to control disease of P. equestris caused by infecting viruses. In this study, for the first time, we characterized viral small interfering RNAs (vsiRNAs) profiles in P. equestris co-infected with CymMV and ORSV through small RNA sequencing technology. CymMV and ORSV small interfering RNAs (siRNAs) demonstrated several general and specific/new characteristics. vsiRNAs, with A/U bias at the first nucleotide, were predominantly 21-nt long and they were derived predominantly (90%) from viral positive-strand RNA. 21-nt siRNA duplexes with 0-nt overhangs were the most abundant 21-nt duplexes, followed by 2-nt overhangs and then 1-nt overhangs 21-nt duplexes in infected P. equestris. Continuous but heterogeneous distribution and secondary structures prediction implied that vsiRNAs originate predominantly by direct Dicer-like enzymes cleavage of imperfect duplexes in the most folded regions of the positive strand of both viruses RNA molecular. Furthermore, we totally predicted 54 target genes by vsiRNAs with psRNATarget server, including disease/stress response-related genes, RNA interference core components, cytoskeleton-related genes, photosynthesis or energy supply related genes. Gene Ontology classification showed that a majority of the predicted targets were related to cellular components and cellular processes and performed a certain function. All target genes were down-regulated with different degree by vsiRNAs as shown by real-time reverse transcription polymerase chain reaction. Taken together, CymMV and ORSV siRNAs played important roles in interplay with P. equestris by down modulating the expression levels of endogenous genes in host plant.

Numerical Simulation of Cone Penetration Tests in Sand Ground Using Critical State Mohr Coulomb Plasticity Model (한계상태 Mohr Coulomb 소성 모델을 활용한 콘관입시험의 수치적 모사)

  • Woo, Sang Inn;Chung, Choong-Ki
    • Journal of the Korean Geotechnical Society
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    • v.35 no.2
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    • pp.37-51
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    • 2019
  • This study focuses on the numerical simulations of the cone penetration tests in a sand ground. The mechanical responses of sand were described using the modified Mohr Coulomb plasticity model based on the critical state soil mechanics. In the plasticity model, the dilatancy angle was not a constant, but a function of the distance to the critical state line from the current state of void ratio and mean effective stress. To simulate cone penetration tests numerically, this study relied on Lagrangian finite element method under the axisymmetric condition. To enable penetration of the cone penetrometer without tearing elements along the symmetric axis, the penetration guide concept was adopted in this study. The results of numerical simulations on the calibration chamber cone penetration tests had good agreement with the experimental results.