• Title/Summary/Keyword: Current Stimulation

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Wireless Energy and Data Transmission Using Inductive Coupling (유도결합방식에 의한 무선 에너지 및 데이터 전송)

  • Lee, Joon-Ha
    • Progress in Medical Physics
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    • v.19 no.1
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    • pp.42-48
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    • 2008
  • Bio-implantable devices such as heart pacers, gastric pacers and drug-delivery systems require power for carrying out their intended functions. These devices are usually powered through a battery implanted with the system or are wired to an external power source. This paper describes an inductive power transmission link, which was developed for an implantable stimulator for direct stimulation of denervated muscles. The carrier frequency is around 1MHz, the transmitter coil has a diameter of 46mm, and the implant coil is 46mm. Data transmission to the implant with amplitude shift keying (ASK) and back to the transmitter with passive telemetry can be added without major design changes. We chose the range of coil spacing (2 to 30mm) to care for lateral misalignment, as it occurs in practical use. If the transmitter coil has a well defined and reliable position in respect to the implant, a smaller working range might be sufficient. Under these conditions the link can be operated in fixed frequency mode, and reaches even higher efficiencies of up to 37%. The link transmits a current of 50 mA over a distance range of 2-15 mm with an efficiency of more than 20% in tracking frequency. The efficiency of the link was optimized with different approaches. A class E transmitter was used to minimize losses of the power stage. The geometry and material of the transmitter coil was optimized for maximum coupling. Phase lock techniques were used to achieve frequency tracking, keeping the transmitter optimally tuned at different coupling conditions caused by coil distance variations.

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Studies on the Cellular Immune Response in Animal Model of Arthritis after the Induction of Oral Tolerance (콜라겐으로 경구 관용을 유도한 관절염 동물 모델의 세포 특이적 면역 반응 조사)

  • Min, So-Youn;Hwang, Sue-Yun;Lee, Jae-sun;Kim, Ju-Young;Lee, Kang-Eun;Kim, Kyung-Wun;Kim, Young-Hun;Do, Ju-Ho;Kim, Ho-Youn
    • IMMUNE NETWORK
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    • v.3 no.2
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    • pp.136-144
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    • 2003
  • Oral administration of antigen has long been considered as a promising alternative for the treatment of chronic autoimmune diseases including rheumatoid arthritis (RA), and oral application of type II collagen (CII) has been proven to improve pathogenic symptoms in RA patients without problematic side effects. To further current understandings about the immune suppression mechanisms mediated by orally administered antigens, we examined the changes in IgG subtypes, T-cell proliferative response, and proportion of interleukin (IL)-10 producing Th subsets in a time course study of collagen induced arthritis (CIA) animal models. We found that joint inflammation in CIA mouse peaked at 5 weeks after first immunization with CII, which was significantly subdued in mice pre-treated by repeated oral administration of CII. Orally tolerized mice also showed increase in their serum level of IgG1, while the level of IgG2a was decreased. T-cell proliferation upon CII stimulation was also suppressed in lymph nodes of mice given oral administration of CII compared to non-tolerized controls. When cultured in vitro in the presence of CII, T-cells isolated from orally tolerized mice presented higher proportion of $CD4^+IL-10^+$ subsets compared to non-tolerized controls. Interestingly, such increase in IL-10 producing cells were obvious first in Peyer's patch, then by 5 weeks after immunization, in mesenteric lymph node and spleen instead. This result indicates that a particular subset of T-cells with immune suppressive functions might have migrated from the original contact site with CII to inflamed joints via peripheral blood after 5 weeks post immunization.

Effect of Gal-Geun-Tang on Antigen-Specific Immune Response (갈근탕(葛根湯)이 면역조절작용에 미치는 영향)

  • Cho, Dae-Yeoun;Yun, Young-Gab;Jung, Myung;Lee, Eun-Hye;Bok, Young-Ok;Jung, Chang-Ohk;Lim, Kyu-Sang
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.29 no.3
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    • pp.134-149
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    • 2016
  • Objectives : Gal-Geun-Tang (GT) has been described from SANGHAN in Korean traditional medicine and known to act against cold, fever, hypertension, and nasal catarrh. However, little has yet been learned about the effect of GT on immune function. In the current study, in vitro and in vivo immunomodulatory activity of GT (water extract) was investigated.Methods : Water extract of GT induced in vitro proliferation of spleen cells and significantly increased their proliferative responses during anti-CD3 activation. Using purified splenic T and B cells, it was revealed that GT has a mitogenic activity to B cells and promotes their proliferation induced by lipopolysaccharide, whereas T cell proliferation was not triggered and GT was rather inhibitory to T cell activation caused by anti-CD3 antibody. In the presence of antigen presenting cells (APC), GT addition resulted in a significant increase of IFNγ and IL-4, but not IL-2, production. However, addition of high concentration (1,000㎍/㎖) of GT led to a marked reduction in T cell cytokine production and under such condition, GT facilitated apoptosis of T cells when examined by flow cytometry with propidium iodide staining.Results : In vivo immunomdulation of GT was also investigated using a mouse model. Following keyhole limpet hemocyanin (KLH) immunization, GT (1 ㎎/day) was orally administered for 9 days. Cell numbers in thymus, spleen and peripheral blood were not altered by GT administration, indicating that such dose is not immunotoxic. Cell numbers in draining lymph nodes (LN) and ex vivo Ag-specific proliferation of LN cells were significantly elevated by GT administration. However, any preferential stimulation of T or B and CD4+ or CD8+ T cell subpopulations was not observed in a flow cytometric analysis of LN cells. This result shows that GT does not promote in vivo B cell proliferation while GT enhances Ag-specific proliferation of LN cells, unlike what was observed in vitro.Conclusions : For a further understanding of in vivo immunomodulatory activity of GT, ex vivo cytokine production of LN cells obtained from KLH-immunized mice was evaluated. Ag-specific IFNγ production was significantly higher in GT-treated mice when compared to PBS-treated control mice. In contrast, IL-4 production in GT-treated group was comparable to control group unlike to in vitro data. In addition, GT administration did not result in any significant differences in serum levels of Ig (IgM, IgG1 and IgG2a) between GT-treated and control groups. Taken together, these data strongly support that GT promotes immune response, more profoundly type 1 helper T cell (Th1) activity and GT may be applicable for treatment of intracellular parasite infection such as viral diseases.

Optical dating of Quaternary sediment (광 여기 루미네센스를 이용한 신기 퇴적층의 연대측정)

  • 홍덕균;최정헌;한정희;최만식;정창식
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.202-211
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    • 2001
  • Luminescence is a physical phenomenon exhibited by many non-conducting, crystalline materials, such as quartz and feldspar. Within the crystals, energy absorbed from ionising radiation frees electrons to move through the crystal lattice and some are trapped at defects in the lattice. Observable luminescence is produced by electrons, released from traps by stimulation by absorption of light, which recombine with lattice defects which act as luminescence centers - optically stimulated luminescence (OSL). In a similar way to thermoluminescence(TL) dating, controlled measurement of the OSL signal can provide a means of determining the time since the last exposure of a layer of sediment to sunlight, the age of the sediment. However, whereas in the thermoluminescence dating of sediment only part of the latent thermoluminescence signal is bleached by sunlight as the sediment is deposited and allowance must be made during the laboratory measurements for the light insensitive component, optically induced luminescence dating has the advantage of working only with light sensitive traps in the crystal. Determination of the time since deposition of Quaternary sediment samples from the OSL of quartz grains using blue light was performed. A series of experiments and recent developments relating OSL dating are described, beginning by identifying the features which make OSL signals suitable for the development of dating method. Additionally, there are suggestions as to future research for obtaining reliable ages and a comment on current best practice on procedures, with the dating results of Quaternary sediment.

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Effect of plant growth regulators on soybean and red bean seedling growth

  • Lee, Won Hee;Ryu, Hee La;Jeong, Eun Ju;Lee, In Jung
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.204-204
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    • 2017
  • In recent years the growth rates of world agricultural production and crop yields have slowed because of rapid urbanization but the agriculture mechanization implies the use of various power sources and improved farm tools and equipment to enhance the efficiency of utilization of various crop input. Therefore the current study was conducted to investigate the growth characteristics of seedlings treated with plant growth regulators for the production of seeds suitable for mechanical formulations of soybeans and red beans. The seeds of Uram bean and Arary red bean were sown in 128 well plug tray as the testing varieties. Three growth inhibitors such as 0.05% hexaconazole, prohexadion-calcium, and 0.1% diniconazole were treated and fifteen representative plants were collected from each treatment at 2, 5, 7, 13, 16, 17, 19, and 20 days interval after treatment. The collected plants were examined for the growth atributes such as plant height, root length, leaf area and chlorophyll. The growth promoter was treated at the 13th day after treatment with growth inhibitor and treated with 0.1% concentration of Pomina ($GA_{4+7}$ 1.8% + 6-benzylaminopurine 1.8%) and Nonaji (gibberellic acid 2% + $GA_{4+7}$ 2%). Initially the growth data was recorded to examine the effect of growth inhibitor, while after treatment with growth promoters, the growth attributes were recorded at 4th and 7th day. As a result of measuring the growth parameter of soybean, the inhibitory effect was shown in the aerobic treatment at the ground level at the 7th day after treatment. At the 4th day of growth promoting agents treatment, the stimulation effect of non - treated plants was greater than that of formalin treatments. As a result of measuring the growth attributes of red bean, In the latter part of the growth, at the 4th day after the growth promoter treatment. This study was able to confirm the effective growth regulators and treatment periods for each crop, and it was possible to control the growth of seedlings. Based on these results, it can be expected that the basis of seedling production technology of crops which is necessary for sowing and transplantation mechanization of agriculturle field can be established.

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Comparative study on the Effects of Platelet-Rich Plasma and Enamel Matrix Protein on Supracrestal bone Regeneration of Dental Implant (혈소판 농축혈장과 법랑기질 단백질이 임플란트 골 연상 골 재생에 미치는 영향에 관한 비교연구)

  • Eun, Hee-Jong;Lim, Sung-Bin;Chung, Chin-Hyung;Hong, Ki-Seok;Lee, Chong-Heon
    • Journal of Periodontal and Implant Science
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    • v.35 no.1
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    • pp.235-250
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    • 2005
  • The current interest in periodontal tissue regeneration has lead to research in bone graft, root surface treatments, guided-tissue regeneration, administration of growth factors, and the use of enamel matrix protein as possible means of regenerating lost periodontal tissue. Several studies have shown that a strong correlation between platelet-rich plasma and the stimulation of remodeling and remineralization of grafted bone exits, resulting in a possible increase of 15-30% in the density of bone trabeculae. The purpose of this study was to study the histopathological results and differences between the use of platelet-rich plasma and the use of enamel matrix $protein(Emdogain^?)$ about bone regeneration at the implant. Implant fixtures were inserted and graft materials placed into the left femur in the experimental group, while the only implant fixtures placed in the control group. In the first experimental group, platelet-rich plasma and xenograft were placed at the supracrestally placed implant site, and in the second experimental group, $Emdogain^{(R)}$ and xenograft placed at the supracrestally placed fixture site. The degree of bone regeneration adjacent to the implant fixture was observed and compared histopathologically at 2, 4, and 8 weeks after implant fixture insertion. The results of the experiment are as follows: 1. The rate of osseointegration to the fixture threads was found to be greater in the experimental group compared to in the control group. 2. The histopathological findings showed that the bone regeneration, the partial osseointegration existed at 4 weeks, and that osseointegration and bone density increaced in the experimental groups at 8 weeks. 3. The results showed that new bone formation and bone remodeling increased in the area near to the fixture in the first and second experimental groups at 8 weeks than at 4 weeks. The results showed that in the area distant from the fixture, new bone formation did not increase and bone remodeling decreased in the first experimental group at 4, 8 weeks, and that new bone formation increased in the second experimental group. 4. The histopathological findings showed that AZ deposition in the first experimental group was remarkable at 2, 8 weeks, and in the second experimental group at 2, 4, 8 weeks in the area distant from the fixture threads.

The Study about Improvement of Neuro Energy Decreased by Energy Saving (에너지절감에 의해 감소되는 뉴로에너지의 증강에 관한 연구)

  • Kim, Myung-Ho;Kang, Dong-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.715-721
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    • 2018
  • This study examined energy saving and elevating the worker's neuro energy (comfort, concentration, physical, and psychological stability) by compensating for the unpleasant tactile sensation to stimulate auditory and olfactory senses and reduce energy consumption. The experiment was conducted in an environment test room under the test conditions of temperature $25[^{\circ}C]$, relative humidity 50[RH%], illumination 1,000[lux] and air current speed 0.02[m/sec] by stimulating the auditory senses with a 1/f change in rhythm and the olfactory senses with an aroma scent. The experiment utilized the method of EEG, which evaluates human body's psychological status via tactile means, and the method of the vibra image, which evaluates the learning abilities, HRV and human body's psychological status via non-tactile means. The subjects were selected as eight university students (four males and four females) in their 20s, the type that have high relative ${\alpha}$(8~13[Hz]) activation in occipital lobe, which brings the highest level of mind stability and concentration, who had no difficulty in physical activities. The subjects' posture and physical activity was fixed to 1met - when the subjects are seated and relaxing in a comfortable environment - and their clothes condition was standardized as 0.7clo. As a result, the sentimental and psychological stability and concentration were the highest in the multisensory stimulation of jasmine scent and change rhythm of an a=1.106 sound source. In addition, under this condition, the relative $M{\alpha}$ and relative $M{\beta}$ increased by 70.49[%] and 89.72[%], respectively; the HRT decreased by 39.09[%]; and the fatigue and tension/anxiety decreased by 36.85[%] and 15.54[%], respectively.

Gentiopicroside Ameliorates the Progression from Hepatic Steatosis to Fibrosis Induced by Chronic Alcohol Intake

  • Yang, Hong-Xu;Shang, Yue;Jin, Quan;Wu, Yan-Ling;Liu, Jian;Qiao, Chun-Ying;Zhan, Zi-Ying;Ye, Huan;Nan, Ji-Xing;Lian, Li-Hua
    • Biomolecules & Therapeutics
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    • v.28 no.4
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    • pp.320-327
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    • 2020
  • In current study, we aimed to investigate whether the gentiopicroside (GPS) derived from Gentiana manshurica Kitagawa could block the progression of alcoholic hepatic steatosis to fibrosis induced by chronic ethanol intake. C57BL/6 mice were fed an ethanol-containing Lieber-DeCarli diet for 4 weeks. LX-2 human hepatic stellate cells were treated with GPS 1 h prior to transforming growth factor-β (TGF-β) stimulation, and murine hepatocyte AML12 cells were pretreated by GPS 1 h prior to ethanol treatment. GPS inhibited the expression of type I collagen (collagen I), α-smooth muscle actin (α-SMA) and tissue inhibitor of metal protease 1 in ethanol-fed mouse livers with mild fibrosis. In addition, the imbalanced lipid metabolism induced by chronic ethanol-feeding was ameliorated by GPS pretreatment, characterized by the modulation of lipid accumulation. Consistently, GPS inhibited the expression of collagen I and α-SMA in LX-2 cells stimulated by TGF-β. Inhibition of lipid synthesis and promotion of oxidation by GPS were also confirmed in ethanol-treated AML12 cells. GPS could prevent hepatic steatosis advancing to the inception of a mild fibrosis caused by chronic alcohol exposure, suggesting GPS might be a promising therapy for targeting the early stage of alcoholic liver disease.

Safety Evaluation of Tobacco Substitute (Herbrette); Inhalation Toxicity, Mutagenicity and Immunotoxicity

  • Song, Kyung Seuk;Park, Kun Ho;Yoo, Gi Yong;Song, Sung-Ok;Kim, Hyun Woo;Kim, Jun Sung;Park, Jin Hong;Eu, Guk Joung;Hua, Jin;Cho, Hyun Sun;Hwang, Soon Kyung;Chang, Seung Hee;Tehrani, Arash Minai;Yu, KyeongNam;Chae, Chan Hee;Cho, Myung Haing
    • Toxicological Research
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    • v.20 no.4
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    • pp.365-374
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    • 2004
  • Inhalation toxicity, mutagenicity, and immunotoxicity tests were performed using a smoke generation system to investigate the safety of Herbrette, a tobacco substitute made with the leaves of Perilla frutescens. ICR mice were exposed to nicotine-free Herbrette smoke with concentrations of 0 (control), 4.08 $\pm$ 1.32 mg/$m^3$ (low dose), 7.72 $\pm$ 2.14 mg/$m^3$ (medium dose) and 12.83 $\pm$ 1.69 mg/$m^3$ (high dose) total particulate matters (TPM) for 4 weeks. When compared to the control group, the body weights, organ weights in the exposed groups did not show any significant differences. However, certain change of several serum chemical data and biochemical parameters were observed, however, the changes were within normal physiological ranges. Moreover, no changes in organ weight, and no gross/microscopic changes were observed between the exposed and control groups. Salmonella typhimurium reverse mutation, in vivo chromosomal aberration and micronucleus assays revealed that Herbrette did not induce mutagenicity. Upon evaluation of peripheral cellular immunity of mice through in vitro lymphocyte proliferation assay, no significant difference was observed in mean stimulation index between the exposed and control groups. Taken together, our results strongly suggest that Herbrette may not cause toxicity on mice under current condition.

cAMP-Dependent Signalling is Involved in Adenosine-Stimulated $Cl^-$ Secretion in Rabbit Colon Mucosa

  • Oh, Sae-Ock;Kim, Eui-Yong;Jung, Jin-Sup;Woo, Jae-Suk;Kim, Yong-Keun;Lee, Sang-Ho
    • The Korean Journal of Physiology and Pharmacology
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    • v.2 no.4
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    • pp.521-527
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    • 1998
  • An important property of the intestine is the ability to secrete fluid. The intestinal secretion is regulated by a number of substances including vasoactive intestinal peptide (VIP), ATP and different inflammatory mediators. One of the most important secretagogues is adenosine during inflammation. However, the controversy concerning the underlying mechanism of adenosine-stimulated $Cl^-$ secretion in intestinal epithelial cells still continues. To investigate the effect of adenosine on $Cl^-$ secretion and its underlying mechanism in the rabbit colon mucosa, we measured short circuit current ($I_{SC}$) under automatic voltage clamp with DVC-1000 in a modified Ussing chamber. Adenosine, when added to the basolateral side of the muocsa, increased $I_{SC}$ in a dose-dependent manner. The adenosine-stimulated $I_{SC}$ response was abolished when $Cl^-$ in the bath solution was replaced completely with gluconate. In addition, the $I_{SC}$ response was inhibited by a basolateral Na-K-Cl cotransporter blocker, bumetanide, and by apical $Cl^-$ channel blockers, dephenylamine-2-carboxylate (DPC), 5-nitro-2-(3-phenyl-propylamino)-benzoate (NPPB), glibenclamide. Amiloride, an epithelial $Na^+$ channel blocker, and 4,4-diisothiocyanato-stilbene-2,2-disulphonate (DIDS), a $Ca^{2+}-activated$ $Cl^-$ channel blocker, had no effect. In the mucosa pre-stimulated with forskolin, adenosine did not show any additive effect, whereas carbachol resulted in a synergistic potentiation of the $I_{SC}$ response. The adenosine response was inhibited by 10 ${\mu}M$ H-89, an inhibitor of protein kinase A. These results suggest that the adenosine-stimulated $I_{SC}$ response is mediated by basolateral to apical $Cl^-$ secretion through a cAMP-dependent $Cl^-$ channel. The rank order of potencies of adenosine receptor agonists was $5'-(N-ethylcarboxamino)adenosine(NECA)>N^6-(R-phenylisopropyl)adenosine(R-$ PIA)>2-[p-(2-carbonylethyl)-phenyl-ethylamino]-5'-N-ethylcarboxaminoadenosine(CGS21680). From the above results, it can be concluded that adenosine interacts with the $A_{2b}$ adenosine receptor in the rabbit colon mucosa and a cAMP-dependent signalling mechanism underlies the stimulation of $Cl^-$ secretion.

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