• Title/Summary/Keyword: Cellular capacity

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Allithiamine Exerts Therapeutic Effects on Sepsis by Modulating Metabolic Flux during Dendritic Cell Activation

  • Choi, Eun Jung;Jeon, Chang Hyun;Park, Dong Ho;Kwon, Tae-Hwan
    • Molecules and Cells
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    • v.43 no.11
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    • pp.964-973
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    • 2020
  • Recent studies have highlighted that early enhancement of the glycolytic pathway is a mode of maintaining the proinflammatory status of immune cells. Thiamine, a wellknown co-activator of pyruvate dehydrogenase complex, a gatekeeping enzyme, shifts energy utilization of glucose from glycolysis to oxidative phosphorylation. Thus, we hypothesized that thiamine may modulate inflammation by alleviating metabolic shifts during immune cell activation. First, using allithiamine, which showed the most potent anti-inflammatory capacity among thiamine derivatives, we confirmed the inhibitory effects of allithiamine on the lipopolysaccharide (LPS)-induced pro-inflammatory cytokine production and maturation process in dendritic cells. We applied the LPS-induced sepsis model to examine whether allithiamine has a protective role in hyper-inflammatory status. We observed that allithiamine attenuated tissue damage and organ dysfunction during endotoxemia, even when the treatment was given after the early cytokine release. We assessed the changes in glucose metabolites during LPS-induced dendritic cell activation and found that allithiamine significantly inhibited glucose-driven citrate accumulation. We then examined the clinical implication of regulating metabolites during sepsis by performing a tail bleeding assay upon allithiamine treatment, which expands its capacity to hamper the coagulation process. Finally, we confirmed that the role of allithiamine in metabolic regulation is critical in exerting anti-inflammatory action by demonstrating its inhibitory effect upon mitochondrial citrate transporter activity. In conclusion, thiamine could be used as an alternative approach for controlling the immune response in patients with sepsis.

A New Frame Offset Assignment Algorithm For Reducing the Soft Handoff Blocking Probability Due to Lack of Frame Offset Capacity (Frame Offset의 불일치로 인하여 발생하는 Soft Handoff Blockig Probability를 줄이기 위한 새로운 Frame Offset Assignment Algorithm)

    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1624-1630
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    • 1999
  • Code division multiple access (CDMA) is a promising air interface technique for cellular systems. When an MS (Mobile Station) moves to an adjacent cell, the handoff between the serving cell and the target cell is needed. Compared with the hard handoffs, the soft handoffs between two CDMA channels with the identical frequency assignments and frame offsets can provide a better quality of service by minimizing the undesirable ping pong phenomenon of back-and forth handoffs between two adjacent cells in conventional hard handoffs. For the soft handoff of a call to an adjacent cell to be successful, the adjacent cell should assign to the call the same frame offset as that being used in the original cell by the call. In this paper, considering the assignment states of the frame offsets of the adjacent cells, a frame offset assignment algorithm for the originated call is proposed. And analytic method for the handoff blocking probability due to the lack of the frame offset capacity is also presented to show the advantage of the proposed algorithm with respect to the soft handoff blocking probability.

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Performance Of Adaptive and Fixed Step Size Power Control Schemes Accommodating Integrated Voice/Video/Data in Wireless Cellular Systems (무선 셀룰라 시스템의 통합된 서비스를 수용하기 위한 적응 및 고정 스텝 크기 전력제어 방법의 성능분석)

  • Kim Jeong-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.1A
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    • pp.9-17
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    • 2004
  • Adapt ive and fixed step size PC (power control) schemes for accommodating voice, video, and data are evaluated according to the different PC command rates and their effects on integrated Voice/Video/Data are investigated. The required minimum power levels are derived as PC thresholds and the effects of PC errors on channel quality and radio 1 ink capacity are investigated. The services with high bit rates and low bit error rates can cause a significant effect on the radio link qualifies of the other types of traffic. The results show that the adapt ive step size PC scheme for voice/video/data services can achieve more capacity and cause less interference to the radio channels because less minimum PIL(Power Increment Level) is required for the specified radio link outage probability.

Distributed MIMO Systems Based on Quantize-Map-and-Forward (QMF) Relaying (양자화 전송 중계 기반 분산 다중 안테나 통신 시스템)

  • Hong, Bi;Choi, Wan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39A no.7
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    • pp.404-412
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    • 2014
  • Exploiting multiple antennas at mobile devices is difficult due to limited size and power. In this paper, a distributed MIMO protocol achieving the capacity of conventinal MIMO systems is proposed and analyzed. For exploiting distributed MIMO features, Quantize-Map-and-Forward (QMF) scheme shows improved performance than Amplify-and-Forward (AF) scheme. Also, the protocol based on multiple access channel (MAC) is proposed to improve the multiplexing gain. We showed that sufficient condition of the number of slave nodes to achieve the gain of a MAC based protocol. Because the base station can support multiple clusters operating in distributed MIMO, the total cellular capacity can be extremely enhanced in proportional to the number of clusters.

Fermented Prunus mume with Probiotics Inhibits 7,12-Dimethylbenz[a]anthracene and 12-O-Tetradecanoyl phorbol-13-acetate Induced Skin Carcinogenesis through Alleviation of Oxidative Stress

  • Lee, Jin-A;Ko, Jae-Hyung;Jung, Bock-Gie;Kim, Tae-Hoon;Hong, Ji-In;Park, Young-Seok;Lee, Bong-Joo
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2973-2978
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    • 2013
  • Maesil (Prunus mume Siebold & Zucc.), a member of the genus Rosaceae, has been reported to have antioxidative effects, as well as anticancer influence in many cancer lines. Thus, this present study was designed to investigate the inhibitory effect of fermented Maesil with probiotics against 7,12-dimethylbenz[a]anthracene (DMBA), 12-O-tetradecanoyl phorbol 13-acetate (TPA)-induced mouse skin carcinogenesis via its antioxidative potential. Mice were fed a diet containing fermented Maesil, containing either 1% (1% FM fed group) or 2% (2% FM fed group) along with probiotics following DMBA and TPA exposure. Continuous ingestion of the experimental feed markedly inhibited skin carcinogenesis, as evidenced by a marked decrease in papilloma numbers and epidermal hyperplasia as well as cellular proliferation and the percentage of proliferating-cell nuclear antigen positive cells. Also, the FM fed group showed an increase of total antioxidant capacity as well as an increased level of phase II detoxifying enzymes such as superoxide dismutase, concurrent with a decreased lipid peroxidation activity level. Taken together, these results suggest that fermented Maesil has the ability to suppress the development of DMBA-TPA induced skin carcinogenesis, via the reduction of lipid peroxidation, enhancing total antioxidant capacity and phase II detoxifying enzyme.

Possibility of Wound Dressing Using Poly(L-leucine)/poly(ethylene glycol)/poly(L-leucine) Triblock Copolymer

  • Kim, Hyeon-Jeong;Jo, Jong-Su
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.249-254
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    • 1997
  • ABA-type block copolymers composed of poly(L-leucine)(PLL) as the A component and poly(ethylene glycol)(PEG) as the B component were synthesized by ring-opening polymerization of L-leucine N-carboxyanhydride initiated by primary amino group located at both ends of PEG chain. A silver sulfadiazine(AgSD)-impregnated wound dressing of sponge-type was prepared by the lyophilization method. Morphological structure of this wound dressing obtained by scanning electron microscopy(SEM) was composed of a dense skin layer and a macroporous inner sponge layer. Equilibrium water content(EWC) of wound dressing was above 10%. It increased with an increased of PEO content in the block copolymer due to the hydrophilicity of PEO. AgSD release from AgSD- impregnated wound dressing in PBS buffer(pH=7.4) was dependent on PEG composition in the block copolymer. Therefore, EWC and release of AgSD can be control by PEG composition. Antibacterial capacity of AgSD-impregnated wound dressing was examined in agar plate against Pseudmonas aeruginosa and Stapplococus aruous. Cytotoxicity of the wound dressing was evaluated by studing mouse skin fibroblast(L929). From the behavior of antimicrobial releasing and the investigation of the suppression of bacterial proliferation, it was supposed that the wound dressing containing antibiotics could protect the wound surfaces from bacterial invasion to suppress the bacterial proliferation effectively. In cytotoxicity observation, cellular damage was reduced by the control led released of AgSD from the LEL sponge matrix of AgSD-medicated wound dressing. In vivo test, granulous tissue formation and wound contraction or the AgSD and DHEA impregnated wound dressing were aster than any other groups.

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Radio Resource Management of CoMP System in HetNet under Power and Backhaul Constraints

  • Yu, Jia;Wu, Shaohua;Lin, Xiaodong;Zhang, Qinyu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.3876-3895
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    • 2014
  • Recently, Heterogeneous Network (HetNet) with Coordinated Multi-Point (CoMP) scheme is introduced into Long Term Evolution-Advanced (LTE-A) systems to improve digital services for User Equipments (UEs), especially for cell-edge UEs. However, Radio Resource Management (RRM), including Resource Block (RB) scheduling and Power Allocation (PA), in this scenario becomes challenging, due to the intercell cooperation. In this paper, we investigate the RRM problem for downlink transmission of HetNet system with Joint Processing (JP) CoMP (both joint transmission and dynamic cell selection schemes), aiming at maximizing weighted sum data rate under the constraints of both transmission power and backhaul capacity. First, joint RB scheduling and PA problem is formulated as a constrained Mixed Integer Programming (MIP) which is NP-hard. To simplify the formulation problem, we decompose it into two problems of RB scheduling and PA. For RB scheduling, we propose an algorithm with less computational complexity to achieve a suboptimal solution. Then, according to the obtained scheduling results, we present an iterative Karush-Kuhn-Tucker (KKT) method to solve the PA problem. Extensive simulations are conducted to verify the effectiveness and efficiency of the proposed algorithms. Two kinds of JP CoMP schemes are compared with a non-CoMP greedy scheme (max capacity scheme). Simulation results prove that the CoMP schemes with the proposed RRM algorithms dramatically enhance data rate of cell-edge UEs, thereby improving UEs' fairness of data rate. Also, it is shown that the proposed PA algorithms can decrease power consumption of transmission antennas without loss of transmission performance.

Comparative Characteristics of Three Human Embryonic Stem Cell Lines

  • Lee, Jung Bok;Kim, Jin Mee;Kim, Sun Jong;Park, Jong Hyuk;Hong, Seok Ho;Roh, Sung Il;Kim, Moon Kyoo;Yoon, Hyun Soo
    • Molecules and Cells
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    • v.19 no.1
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    • pp.31-38
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    • 2005
  • Human embryonic stem (hES) cells have unique features including unlimited growth capacity, expression of specific markers, normal karyotypes and an ability to differentiate. Many investigators have tried to use hES cells for cell-based therapy, but there is little information about the properties of available hES cell lines. We compared the characteristics of three hES cell lines. The expression of SSEA-1, -3, -4, and APase, was examined by immunocytochemistry, and Oct-4 expression was analyzed by RT-PCR. Differentiation of the hES cells in vitro and in vivo led to the formation of embryoid bodies (EBs) or teratomas. We examined the expression of tissue-specific markers in the differentiated cells by semiquantitative RT-PCR, and the ability of each hES cell line to proliferate was measured by flow cytometry of DNA content and ELISA. The three hES cell lines were similar in morphology, marker expression, and teratoma formation. However there were significant differences (P < 0.05) between the differentiated cells formed by the different cell lines in levels of expression of tissue-specific markers such as renin, kallikrein, Glut-2, ${\beta}-$ and ${\delta}-globin$, albumin, and ${\alpha}1-antitrypsin$ (${\alpha}1-AT$). The hES cell lines also differed in proliferative activity. Our observations should be useful in basic and clinical hES cell research.

Performance of 3-Dimensional Frequency Reuse Patterns and Their Application to Carrier-Aggregated Systems (3차원 주파수 재사용 패턴의 성능 및 반송파 결합을 사용하는 시스템으로의 적용 방안)

  • Sung, Jihoon;Sung, Wonjin
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.11
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    • pp.1256-1263
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    • 2012
  • Assigning different frequency resources among adjacent cells, namely the frequency reuse technique can be utilized to mitigate intercell interference, which is a major cause of performance degradation in cellular systems. Since most of conventional frequency reuse patterns are limited to the two-dimensional environment, the research for the three-dimensional frequency reuse would be beneficial especially for the implementation of femto cells in downtown office buildings. We propose frequency reuse patterns in three-dimensional space and evaluate their performance of each pattern in terms of channel capacity. In particular, we show that the proposed three-dimensional frequency reuse patterns can be applied for carrier-aggregated transmission of LTE-Advanced systems. The performance of the proposed patterns is evaluated using computer simulation.

Effects of Gentiana scabra var. buergeri Extract on Toxoplasmastic Activity of Macrophages

  • Kang, Sung-Gu;Ryang, Yong-Suk;Kim, In-Sik
    • Biomedical Science Letters
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    • v.9 no.2
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    • pp.85-91
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    • 2003
  • Gentiana scabra var. buergeri (G. scabra) is a herb known to have therapeutic effect in infection diseases. We studied cellular activation and antitoxoplasmosis in macrophages after G. scabra stimulation. Macrophage activation was detected by nitrite production. Macrophages were treated with G. scabra extracted with water or methanol. Maximal nitrite production was detected in macrophages after stimulation of G. scabra extract 0.1 mg/ml. Maximal nitrite concentration was 23.22 0.003 uM/L in macrophages after water extract of G. scabra and was 24.07 1.41 uM/L after methanol extract of G. scabra. Effect of G. scabra in the phagocytic capacity of macrophages was monitored by using PI (percentage of macrophage infected by T gondii) method. The minimum PI (42.5 2.31) was detected in macrophages treated by water extract of G. scabra 0.1 mg/ml before infection of T gondii. We also examined toxoplasmastatic capacity of macrophage using FI (fold increase) method. The minimum FI (4.46 1.16) was shown in macrophages after water extract of G. scabra 0.1 mg/ml pretreatment before infection. Under electron microscope, proliferation of T gondii was inhibited by extract of G. scabra treatment in macrophages and the mitochondrion and lysosomal vacuoles within cells were increased. Taken together, G. scabra extract activates macrophages and induces toxopalsmastatic activity after T gondii infection. It is suggested that G. scabra may be used as a therapeutic drug against toxoplasmosis.

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