• 대한의생명과학회지
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• 제29권3호
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• pp.178-183
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• 2023

Natural killer (NK) cells are innate cytotoxic lymphoid cells that actively prevent neoplastic development, growth, and metastatic dissemination in a process called cancer immunosurveillance. Regulation of the cytotoxic activity of NK cells relies on integrated interactions between inhibitory receptors and numerous activating receptors that act in tandem to eliminate tumor cells efficiently. Conventional chemotherapy is designed to produce an anti-proliferative or cytotoxic effect on early tumor cell division. Therapies designed to kill cancer cells and simultaneously maintain host anti-tumor immunity are attractive strategies for controlling tumor growth. Depending on the drug and dose used, several chemotherapeutic agents cause DNA damage and cancer cell death through apoptosis, immunogenic cell death, or other forms of non-killing (i.e., mitotic catastrophe, senescence, autophagy). Among stress-induced immunostimulatory proteins, changes in the expression levels of NK cell activating and inhibitory ligands and tumor cell death receptors play an important role in the detection and elimination by innate immune effectors including NK cells. Therefore, we will address how these cytotoxic lymphocytes sense and respond to high and low concentrations of drug-induced stress to the drug cisplatin, among the various types of drugs that contribute to their anticancer activity.

• Molecules and Cells
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• 제46권11호
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• pp.710-724
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• 2023

The plant defense responses to microbial infection are tightly regulated and integrated with the developmental program for optimal resources allocation. Notably, the defense-associated hormone salicylic acid (SA) acts as a promoter of flowering while several plant pathogens actively target the flowering signaling pathway to promote their virulence or dissemination. Ralstonia pseudosolanacearum inject tens of effectors in the host cells that collectively promote bacterial proliferation in plant tissues. Here, we characterized the function of the broadly conserved R. pseudosolanacearum effector RipL, through heterologous expression in Arabidopsis thaliana. RipL-expressing transgenic lines presented a delayed flowering, which correlated with a low expression of flowering regulator genes. Delayed flowering was also observed in Nicotiana benthamiana plants transiently expressing RipL. In parallel, RipL promoted plant susceptibility to virulent strains of Pseudomonas syringae in the effector-expressing lines or when delivered by the type III secretion system. Unexpectedly, SA accumulation and SA-dependent immune signaling were not significantly affected by RipL expression. Rather, the RNA-seq analysis of infected RipL-expressing lines revealed that the overall amplitude of the transcriptional response was dampened, suggesting that RipL could promote plant susceptibility in an SA-independent manner. Further elucidation of the molecular mechanisms underpinning RipL effect on flowering and immunity may reveal novel effector functions in host cells.

• BMB Reports
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• 제40권5호
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• pp.765-772
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• 2007

Eosinophils act as effectors in the inflammatory reactions of allergic diseases including atopic dermatitis. Atopic dermatitis patients and others with allergic disorders suffer from eosinophilia, an accumulation of eosinophils due to increased survival or decreased apoptosis of eosinophils. In this study, a differential phosphoproteome analysis of AML14.3D10 eosinophil cell line after treatment with IL-5 or dexamethasone was conducted in an effort to identify the phosphoproteins involved in the proliferation or apoptosis of eosinophils. Proteins were separated by 2-DE and alterations in phosphoproteins were then detected by Pro-Q Diamond staining. The significant quantitative changes were shown in nineteen phosphoproteins including retinoblastoma binding protein 7, MTHSP75, and lymphocyte cytosolic protein 1. In addition, seven phosphoproteins including galactokinase I, and proapolipoprotein, were appeared after treatment with IL-5 or dexamethasone. Especially, the phospho-APOE protein was down-regulated in IL-5 treated AML14.3D10, while the more heavily phosphorylated APOE form was induced after dexamethasone treatment. These phosphoproteome data for the AML14.3D10 cell line may provide clues to understand the mechanism of eosinophilia as well as allergic disorders including atopic dermatitis.

• The Plant Pathology Journal
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• 제31권3호
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• pp.245-251
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• 2015

Alternative hosts increase the difficulty of disease management in crops because these alternate hosts provide additional sources of primary inoculum or refuges for diversity in the pathogen gene pool. Agropyron cristatum (crested wheatgrass), Bromus inermis (smooth bromegrass), Pascopyrum smithii (western wheatgrass), Stipa viridula (green needlegrass), and Thinopyrum intermedium (intermediate wheatgrass), commonly identified in range, prairie, verge, and soil reclamation habitats, serve as additional hosts for Pyrenophora tritici-repentis, the cause of tan spot in wheat (Triticum aestivum L.). A. cristatum (five lines), B. inermis (seven lines), P. smithii (four lines), S. viridula (two lines), and T. intermedium (six lines) were tested for their reactions to 30 representative P. tritici-repentis isolates from races 1-5. Plants were grown until the two-three-leaf stage in a greenhouse, inoculated individually with the 30 isolates, held at high humidity for 24 h, and rated after 7 days. All lines developed lesion types 1-2 (resistant) based on a 1-5 rating scale. Also, leaves from an additional plant set were infiltrated with two host selective toxins, Ptr ToxA as a pure preparation and Ptr ToxB as a dilute crude culture filtrate. All lines were insensitive to the toxins. Results indicate that these grass hosts have a limited or nonsignificant role in tan spot epidemiology on wheat in the northern Great Plains. Additionally, the resistant reactions demonstrated by the grass species in this research indicate the presence of resistance genes that can be valuable to wheat breeding programs for improving wheat resistance to P. tritici-repentis.

• Journal of Nutrition and Health
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• 제48권5호
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• pp.451-456
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• 2015

Purpose: Neuronal apoptotic events induced by aging and hypoxic/ischemic conditions is an important risk factor in neurodegenerative diseases such as ischemia stroke and Alzheimer's disease. The peel of Citrus sunki Hort. ex Tanaka has long been used as a traditional medicine, based on multiple biological activities including anti-oxidant, anti-inflammation, and anti-obesity. In the current study, we examined the actions of fermented C. sunki peel extract against cobalt chloride ($CoCl_2$)-mediated hypoxic death in human neuroblastoma SH-SY5Y cells. Methods: Cell viability was measured by trypan blue exclusion. Expression of apoptosis related proteins and release of cytochrome c were detected by western blot. Production of intracellular reactive oxygen species (ROS) and apoptotic morphology were examined using 2',7'-dichlorofluorescin diacetate (DCF-DA) and 4',6-diamidino-2-phenylindole (DAPI) staining. Results: Exposure to $CoCl_2$, a well-known mimetic agent of hypoxic/ischemic condition, resulted in neuronal cell death via caspase-3 dependent pathway. Extract of fermented C. sunki peel significantly rescued the $CoCl_2$-induced neuronal toxicity with the cell viability and appearance of apoptotic morphology. Cytoprotection with fermented C. sunki peel extract was associated with a decrease in activities of caspase-3 and cleavage of poly (ADP ribose) polymerase (PARP). In addition, increase in the intracellular ROS and release of cytochrome c from mitochondria to the cytosol were inhibited by treatment with extract of fermented C. sunki peel. Conclusion: Based on these data, fermented C. sunki peel extract might have a protective effect against $CoCl_2$-induced neuronal injury partly through generation of ROS and effectors involved in mitochondrial mediated apoptosis.

• 전자공학회논문지SC
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• 제43권5호
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• pp.10-18
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• 2006

본 논문에서는 다중 로봇 시스템에서 물체와 로봇 팔끝 간에 접촉 마찰이 존재할 때 이 로봇 시스템의 조작도를 해석하는 새로운 방법을 제안한다. 로봇이 물체를 떨어뜨리지 않고 잡고 있으려면, 로봇이 물체에 가하는 힘 벡터가 friction cone 내부에 존재 해야만 한다. 이러한 friction cone 내부를 나타내는 식은 일반적으로 비선형 형태로 되어 있기 때문에 기존의 조작도 분석 방법에 이 식을 구속 조건으로 적용하기가 쉽지 않다. 따라서 본 논문에서는 이러한 friction cone 내부를 다각뿔로 근사함으로써 선형적인 구속 조건으로 표현하였다. 또한 선행 연구에서 찾지 못했던 부분을 새롭게 찾아내었다. 그리고 다중 로봇 시스템에 조작도를 나타내는 물체 중심의 가속도를 구하기 위해서, 먼저 선형계획법을 통해서 허용 가능한 토크의 영역을 구하였다. 이 토크의 영역을 선형 변환을 통해 최종적으로 물체의 최대 가속도의 영역을 구하였다. 본 방법의 타당성을 입증하기 위해서 두 대로 구성 된 다중 로봇 시스템과 PUMA560 로봇 시스템에 적용하였다.

• 대한기계학회논문집A
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• 제30권7호
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• pp.741-749
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• 2006

For last couple of decades, uses of TFI-LCDs have been expanded to many FPD(Flat Panel Display) applications including mobile displays, desktop monitors and TVs. Furthermore, there has been growing demand for increasingly larger LCD TVs. In order to meet this demand as well as to improve productivity, LCD manufactures have continued to install larger-generation display fabrication facilities which are capable of producing more panels and larger displays per mother glass(substrate). As the size of mother glass becomes larger, a robot required to handle the glass becomes bigger accordingly, and its end effectors(arms) are extended to match the glass size. With this configuration, a considerable static deflection occurs at the end of the robot arms. In order to stack maximum number of mother glasses on a given footprint, the static deflection should be compensated. This paper presents a novel static deflection compensation algorithm. This algorithm requires neither measurement instrument nor additional vertical axis on the robot. It is realized by robot controller software. The forward and inverse kinematics considering compensation always guarantees a unique solution, so the proposed algorithm can be applied to an arbitrary robot position. The algorithm reduced static deflection by 40% in stationary robot state experiment. It also improved vertical path accuracy up to 60% when the arm was running at its maximum speed. This algorithm has been commercialized and successfully applied to a seventh-generation LCD glass-handling robot.

• The Plant Pathology Journal
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• 제33권5호
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• pp.458-466
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• 2017

Xanthomonas oryzae pv. oryzae (Xoo), the causative agent of bacterial blight, is a major threat to rice productivity. Here, we performed RNA-Seq based transcriptomic analysis of Xoo transcripts isolated under in planta growth (on both susceptible and resistant hosts) and in vitro culture conditions. Our in planta extraction method resulted in successful enrichment of Xoo cells and provided RNA samples of high quality. A total of 4,619 differentially expressed genes were identified between in planta and in vitro growth conditions. The majority of the differentially expressed genes identified under in planta growth conditions were related to the nutrient transport, protease activity, stress tolerance, and pathogenicity. Among them, over 1,300 differentially expressed genes were determined to be secretory, including 184 putative type III effectors that may be involved in Xoo pathogenicity. Expression pattern of some of these identified genes were further validated by semi-quantitative RT-PCR. Taken together, these results provide a transcriptome overview of Xoo under in planta and in vitro growth conditions with a focus on its pathogenic processes, deepening our understanding of the behavior and pathogenicity of Xoo.

• BMB Reports
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• 제44권2호
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• pp.140-145
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• 2011

Impaired responsiveness of platelets to epinephrine (epi) and other catecholamines (CA) has been reported in approximately 20% of the healthy Korean and Japanese populations. In the present study, platelet aggregation induced by epi was potentiated by RO 31-8220 (RO) or G$\ddot{o}$ 6983 (G$\ddot{o}$). Phosphorylated Akt (p-Akt) was very low in epi-stimulated PRP from CA-hypo- responders (CA-HY), whereas it was detected in those from CA-good responders (CA-GR). RO and G$\ddot{o}$ increased p-Akt, one of the major downstream effectors of phosphoinositol-3 kinase (PI3K), in epi-stimulated PRP from both groups. Wortmannin, a PI3K inhibitor, attenuated the RO or G$\ddot{o}$-induced potentiation of p-Akt in epi-stimulated PRP, suggesting positive effects for RO and G$\ddot{o}$ on PI3K. $TXA_2$ formation was increased by the addition of either RO or G$\ddot{o}$ in epi-stimulated platelets. The present data also suggest that impaired Akt phosphorylation may be responsible for epinephrine hypo-responsiveness of platelets.

• Journal of Korean Neurosurgical Society
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• 제49권4호
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• pp.248-251
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• 2011

Objective : In the field of spinal surgery, a few laboratory results or clinical cases about robotic spinal surgery have been reported. In vivo trials and development of related surgical instruments for spinal surgery are required before its clinical application. We investigated the use of the da $Vinci^{(R)}$ Surgical System in spinal surgery at the craniovertebral junction in a human cadaver to demonstrate the efficacy and pitfalls of robotic surgery. Methods : Dissection of pharyngeal wall to the exposure of C1 and odontoid process was performed with full robotic procedure. Although assistance of another surgeon was necessary for drilling and removal of odontoid process due to the lack of appropriate end-effectors, successful robotic procedures for dural sutures and exposing spinal cord proved its safety and dexterity. Results : Robot-assisted odontoidectomy was successfully performed in a human cadaver using the da $Vinci^{(R)}$ Surgical System with few robotic arm collisions and minimal soft tissue damages. Da $Vinci^{(R)}$ Surgical System manifested more dexterous movement than human hands in the deep and narrow oral cavity. Furthermore, sutures with robotic procedure in the oral cavity demonstrated the advantage over conventional procedure. Conclusion : Presenting cadaveric study proved the probability of robot-assisted transoral approach. However, the development of robotic instruments specific to spinal surgery must first precede its clinical application.