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The complement system: a potential target for the comorbidity of chronic pain and depression

  • Shanshan Tang;Wen Hu;Helin Zou;Qingyang Luo;Wenwen Deng;Song Cao
    • The Korean Journal of Pain
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    • v.37 no.2
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    • pp.91-106
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    • 2024
  • The mechanisms of the chronic pain and depression comorbidity have gained significant attention in recent years. The complement system, widely involved in central nervous system diseases and mediating non-specific immune mechanisms in the body, remains incompletely understood in its involvement in the comorbidity mechanisms of chronic pain and depression. This review aims to consolidate the findings from recent studies on the complement system in chronic pain and depression, proposing that it may serve as a promising shared therapeutic target for both conditions. Complement proteins C1q, C3, C5, as well as their cleavage products C3a and C5a, along with the associated receptors C3aR, CR3, and C5aR, are believed to have significant implications in the comorbid mechanism. The primary potential mechanisms encompass the involvement of the complement cascade C1q/C3-CR3 in the activation of microglia and synaptic pruning in the amygdala and hippocampus, the role of complement cascade C3/C3a-C3aR in the interaction between astrocytes and microglia, leading to synaptic pruning, and the C3a-C3aR axis and C5a-C5aR axis to trigger inflammation within the central nervous system. We focus on studies on the role of the complement system in the comorbid mechanisms of chronic pain and depression.

Characteristics of high-temperature single-crystalline 3C-SiC piezoresistive pressure sensors (고온 단결정 3C-SiC 압저항 압력센서 특성)

  • Thach, Phan Duy;Chung, Gwiy-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.274-274
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    • 2008
  • This paper describes on the fabrication and characteristics of a 3C-SiC (Silicon Carbide) micro pressure sensor for harsh environment applications. The implemented micro pressure sensor used 3C-SiC thin-films heteroepitaxially grown on SOI (Si-on-insulator) structures. This sensor takes advantages of the good mechanical properties of Si as diaphragms fabricated by D-RIE technology and temperature properties of 3C-SiC piezoresistors. The fabricated pressure sensors were tasted at temperature up to $250^{\circ}C$ and indicated a sensitivity of 0.46 mV/V*bar at room temperature and 0.28 mV/V*bar at $250^{\circ}C$. The fabricated 3C-SiC/SOI pressure sensor presents a high-sensitivity and excellent temperature stability.

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Preparation of B4C-Al2O3 Composite Powder by Self-propagation High-temperature Synthesis(SHS) Process under High Pressure (고압 자전 고온반응 합성법에 의한 B4C-Al2O3복합분말 제조)

  • 임경란;강덕일;김창삼
    • Journal of the Korean Ceramic Society
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    • v.40 no.1
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    • pp.18-23
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    • 2003
  • Composite powder of$B_4C-A1_2O_3$was prepared from a mixed powder of$B_2O_3/A1/C$by SHS under argon pressure instead of using a chemical furnace. A mixture of$B_2O_3,$Al and C powder (equivalent amounts to the reaction,$2B_2O_3+4A1+C=B_4C+2A1_2O_3)$was ball milled for 2 h. The mixed powder was placed in a SHS reactor and filled with 10 atm of argon gas and ignited. The inner and outer products were the same by XRD analysis. It was consisted of a composite powder of$B_4C-A1_2O_3$without $AlB_{12}/C_2$which was always produced using a chemical furnace. The composite powder was about$60~100{mu}m$size which was composed of crystalline particles of about 0.3~l${mu}m$size. But when 15 atm of argon was employed, partial sintering took place to give rise hard composite powder of$15~25{mu}m$$B_4C$with $0.1~0.2{mu}m$$A1_2O_3.$

The Effect of Potassium Oxalate on Hydration of Cement with the Ternary System of $C_2$S-C$_4$A$_3$-CS (C$_2$S-C$_4$A$_3$-CS 3성분계 시멘트의 수화에 미치는 Potassium Oxalate 첨가의 영향)

  • 강승규;최상홀
    • Journal of the Korean Ceramic Society
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    • v.35 no.12
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    • pp.1241-1248
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    • 1998
  • $\beta$-C2S and C4A3 were synthesized separately and potassium oxalate was added to each system. The ad-ditive caused calcium ions in solution to decrease at early time in hydration and promoted hydration reac-tion. And then clinker which is mainly composed of $\beta$-C2S and C4A3 was synthesized at 130$0^{\circ}C$ After ad-ding potassium oxalate to it behavior of hydration was observed. It showed that the additive promoted et-tringtie formation at early time and C-S-H formation as time went on.

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Thermoelectric Properties of Al4C3-doped α-SiC (Al4C3 첨가 α-SiC의 열전변환특성)

  • 박영석;배철훈
    • Journal of the Korean Ceramic Society
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    • v.40 no.10
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    • pp.991-997
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    • 2003
  • The effect of A1$_4$C$_3$ additive on the thermoelectric properties of SiC ceramics were studied. Porous SiC ceramics with 47∼59% relative density were fabricated by sintering the pressed $\alpha$-SiC powder compacts with A1$_4$C$_3$at 2100∼220$0^{\circ}C$ for 3 h in Ar atmosphere. Crystalline phases of the sintered bodies were identified by powder X-Ray Diffraction (XRD) and their microstructures were observed with a Scanning Electron Microscope (SEM). In the case of A1$_4$C$_3$ addition, the phase transformation of 6H-SiC to 4H-SiC could be observed during sintering. The Seebeck coefficient and electrical conductivity were measured at 550∼95$0^{\circ}C$ in Ar atmosphere. In the case of undoped specimens, the Seebeck coefficients were positive (p-type semiconducting) possibly due to a dominant effect of the acceptor impurities (Al, Fe) contained in the starting powder and electrical conductivity increased as increasing sintering temperature. Electrical conductivity of A1$_4$C$_3$doped specimen is larger than that of undoped specimen under the same condition, which might be due to the reverse phase transformation and increasing of carrier density. And the Seebeck coefficient of A1$_4$C$_3$ doped specimen is also larger than that of undoped specimen. The density of specimen, the amount of addition and sintering atmosphere had significant effects on the thermoelectric property.

Effect if Grain Size on Plasticity of Ti$_3$SiC$_2$ (Ti$_3$SiC$_2$의 소성 변형 특성에 미치는 결정립 크기의 효과)

  • 이승건
    • Journal of the Korean Ceramic Society
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    • v.35 no.8
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    • pp.807-812
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    • 1998
  • Mechanical properties of two types of polycrystlline {{{{ { { Ti}_{3 }SiC }_{2 } }} with different grain size were investigated. A fine grain {{{{ { { Ti}_{3 }SiC }_{2 } }} has a higher fracture strength and hardness. Plot of strength versus Vickers indentation load indicated that {{{{ { { Ti}_{3 }SiC }_{2 } }} has a high flaw tolerance. Hertzian indentation test using a spherical indenter was used to study elastic and plastic behavior in {{{{ { { Ti}_{3 }SiC }_{2 } }}. Indentation stress-strain curves of each material are made to evaluate the plasticity of {{{{ { { Ti}_{3 }SiC }_{2 } }} Both find and coarse grain {{{{ { { Ti}_{3 }SiC }_{2 } }} showed high plasticity. In-dentation stress-strain curve of coarse grain {{{{ { { Ti}_{3 }SiC }_{2 } }} deviated even more from an ideal elastic limit in-dicating exceptional plasticity in this material. Deformation zones were formed below the contact as well as around the contact area in both materials but the size of deformation zone in coarse grain {{{{ { { Ti}_{3 }SiC }_{2 } }} was much larger than that in fine grain {{{{ { { Ti}_{3 }SiC }_{2 } }} Intragrain slip and kink would account for high plasticity. Plastic behavior of {{{{ { { Ti}_{3 }SiC }_{2 } }} was strongly influenced by grain size.

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Bioconversion of Cyanidin-3-Rutinoside to Cyanidin-3-Glucoside in Black Raspberry by Crude α-ʟ-Rhamnosidase from Aspergillus Species

  • Lim, Taehwan;Jung, Hana;Hwang, Keum Taek
    • Journal of Microbiology and Biotechnology
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    • v.25 no.11
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    • pp.1842-1848
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    • 2015
  • Cyanidin-3-glucoside (C3G) has been known to be more bioavailable than cyanidin-3-rutinoside (C3R), the most abundant anthocyanin in black raspberry (Rubus occidentalis). The aim of this study was to enhance the bioavailability of anthocyanins in black raspberry by cleaving ʟ-rhamnose in C3R using crude enzyme extracts (CEEs) from Aspergillus usamii KCTC 6956, A. awamori KCTC 60380, A. niger KCCM 11724, A. oryzae KCCM 12698, and A. kawachii KCCM 32819. The enzyme activities of the CEEs were determined by a spectrophotometric method using ρ-nitrophenyl-rhamnopyranoside and ρ-nitrophenyl-glucopyranoside. The CEE from A. usamii had the highest α-ʟ-rhamnosidase activity with 2.73 U/ml at 60℃, followed by those from A. awamori and A. niger. When bioconversion of C3R to C3G in black raspberry was analyzed by HPLC-DAD, the CEEs from A. usamii and A. awamori hydrolyzed 95.7% and 95.6% of C3R to C3G, respectively, after 2 h incubation. The CEEs from A. kawachii and A. oryzae did not convert C3R to C3G in black raspberry.

Effects of In-situ doping Concentration on the Characteristics of Porous 3C-SiC Thin Films (In-situ 도핑량이 다공성 3C-SiC 박막의 특성에 미치는 영향)

  • Kim, Kang-San;Chung, Gwiy-Sang
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.6
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    • pp.487-490
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    • 2010
  • This paper describes the elecrtical and optical characteristics of $N_2$ doped porous 3C-SiC films. Polycrystalline 3C-SiC thin films are anodized by $HF+C_2H_5OH$ solution with UV-LED exposure. The growth of in-situ doped 3C-SiC thin films on p-type Si (100) wafers is carried out by using APCVD (atmospheric pressure chemical vapor deposition) with a single-precursor of HMDS (hexamethyildisilane: $Si_2(CH_3)_6)$. 0 ~ 40 sccm $N_2$ was used for doping. After the growth of doped 3C-SiC, porous 3C-SiC is formed by anodization with $7.1\;mA/cm^2$ current density for anodization time of 60 sec. The average pore diameter is about 30 nm, and etched area is increased with $N_2$ doping rate. These results are attributed to the decrease of crystallinity by $N_2$ doping. Mobility is dramatically decreased in porous 3C-SiC. The band gaps of polycrystalline 3C-SiC films and doped porous 3C-SiC are 2.5 eV and 2.7 eV, respectively.

Triglyceride Composition of Perilla Oil (들깨기름의 Triglyceride 조성(組成)에 관한 연구)

  • Park, Yeung-Ho;Kim, Dong-Soo;Chun, Suck-Jo
    • Korean Journal of Food Science and Technology
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    • v.15 no.2
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    • pp.164-169
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    • 1983
  • The triglyceride composition of perilla oil was investigated by high performance liquid chromatography (HPLC) in combination with gas liquid chromatography (GLC). The triglycerides were separated from perilla oil by thin layer chromatography (TLC), and fractionated into five groups on the basis of their partition numbers by reverse phase HPLC on a column packed with ${\mu}-Bondapak\;C_{18}$ using methanol-chloroform mixture as a solvent. Each of these collected fractions gave one to three peaks in the GLC chromatograms according to the acyl carbon number of the triglyceride, and fatty acid composition of the triglyceride was also analyzed by GLC. The results indicate that the perilla oil consists of fifteen kinds of triglycerides, and the major triglycerides in perilla oil were as follows: 68.0% of $(C_{18:3},\;C_{18:3},\;C_{18:3})$, 6.7% of $(C_{18:2},\;C_{18:3},\;C_{18:3})$, 5.9% of $(C_{18:1},\;C_{18:3},\;C_{18:3})$, 4.3% of $(C_{16:0},\;C_{18:3},\;C_{18:3})$, 3.8% of $(C_{18:1},\;C_{18:2},\;C_{18:3})$, 3.2% of $(C_{18:1},\;C_{18:1},\;C_{18:3})$, 2.0% of $(C_{16:0},\;C_{18:2},\;C_{18:3})$, 1.5% of ($C_{18:2},\;C_{18:2},\;C_{18:3})$, 1.0% of $(C_{16:0},\;C_{18:1},\;C_{18:3})$.

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Fabrication of polycrystalline 3C-SiC diode for harsh environment micro chemical sensors and their characteristics (극한 환경 마이크로 화학센서용 다결정 3C-SiC 다이오드 제작과 그 특성)

  • Shim, Jae-Cheol;Chung, Gwiy-Sang
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.195-196
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    • 2009
  • This paper describes the fabrication and characteristics of polycrystalline 3C-SiC thin film diodes for extreme environment applications, in which the this thin film was deposited onto oxidized Si wafers by APCVD using HMDS In this work, the optimized growth temperature and HMDS flow rate were $1,100^{\circ}C$ and 8sccm, respectively. A Schottky diode with a Au, Al/poly 3C-SiC/$SiO_2$/Si(n-type) structure was fabricated and its threshold voltage ($V_d$), breakdown voltage, thickness of depletion layer, and doping concentration ($N_D$) values were measured as 0.84V, over 140V, 61nm, and $2.7{\times}10^{19}cm^2$, respectively. To produce good ohmic contact, Al/3C-SiC were annealed at 300, 400, and $500^{\circ}C$ for 30min under a vacuum of $5.0{\times}10^{-6}$Torr. The obtained p-n junction diode fabricated by poly 3C-SiC had similar characteristics to a single 3C-SiC p-n junction diode.

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