An environmental radiation monitoring system based on high pressurized ionization chamber has been used for on-line gamma monitoring surrounding the KAERI (Korea Atomic Energy Research Institute), which transmits the dose data measured from ion chamber on the site via radio frequency to a central processing computer and stores the transmitted real-time data. Although communication using radio frequency has several advantages such as effective and economical transmission, storage, and data process, there is one main disadvantage that data loss during transmission often happens because of unexpected communication problems. It is possible to restore the loss data by off-line such as floppy disk but the simultaneous process and display of current data as well as the backup data are very difficult in the present on-line system. In this work, a new electronic circuit board and the operation software applicable to the conventional environmental radiation monitoring system are developed and the automatical synchronization of the ion chamber unit and the central processing computer is carried out every day. This system is automatically able to restore the backup data within 34 hours without additional equipments and also display together the current data as well as the transmitted backup data after checking time flag.
Kim, Do Yun;Chae, Joo Wung;Lim, Chang Hun;Heo, Bong Ha;Park, Keun Suk;Lee, Hyung Gon;Choi, Jeong Il;Yoon, Myung Ha;Kim, Woong Mo
The Korean Journal of Pain
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v.29
no.3
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pp.164-171
/
2016
Background: Nefopam has been known as an inhibitor of the reuptake of monoamines, and the noradrenergic and/or serotonergic system has been focused on as a mechanism of its analgesic action. Here we investigated the role of the spinal dopaminergic neurotransmission in the antinociceptive effect of nefopam administered intravenously or intrathecally. Methods: The effects of intravenously and intrathecally administered nefopam were examined using the rat formalin test. Then we performed a microdialysis study to confirm the change of extracellular dopamine concentration in the spinal dorsal horn by nefopam. To determine whether the changes of dopamine level are associated with the nefopam analgesia, its mechanism was investigated pharmacologically via pretreatment with sulpiride, a dopaminergic D2 receptor antagonist. Results: When nefopam was administered intravenously the flinching responses in phase I of the formalin test were decreased, but not those in phase II of the formalin test were decreased. Intrathecally injected nefopam reduced the flinching responses in both phases of the formalin test in a dose dependent manner. Microdialysis study revealed a significant increase of the level of dopamine in the spinal cord by intrathecally administered nefopam (about 3.8 fold the baseline value) but not by that administered intravenously. The analgesic effects of intrathecally injected nefopam were not affected by pretreatment with sulpiride, and neither were those of the intravenous nefopam. Conclusions: Both the intravenously and intrathecally administered nefopam effectively relieved inflammatory pain in rats. Nefopam may act as an inhibitor of dopamine reuptake when delivered into the spinal cord. However, the analgesic mechanism of nefopam may not involve the dopaminergic transmission at the spinal level.
Journal of Korean Academy of Oral and Maxillofacial Radiology
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v.24
no.1
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pp.67-77
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1994
The purpose of this study was to investigate the irradiatiion effects on the capillary and endothelial cell in the submandibular gland. Sprague-Dawley strain male rats were singly irradiated to their neck region with the dose of 5Gy by 6MV X-irradiation and sacrificed on the 6 hours, 12 hours, 1, 3, 7, and 14days after irradiation. The authors observed the histological changes of the capillary at H & E and PAS staining under a light microscope, and also observed the ultrastructural changes of the endothelial cell using a transmission electron microscope. The obtaining results were as follows: 1. In the light microscopic examination, the capillary density was slightly increased on the 1day after irradiation, and increased until the 7 days after irradiatiion. After then, capillary density was apparently decreased. 2. The reaction to PAS staining at acinar cells was decreased on the 6 hours after irradiation, and recovered on the 7days after irradiation. But reaction was decreased on the 14days after irradiation agan, after then, gradually recovered with days. 3. In the transmission electron microscopic examination, mild proliferation of cytoplasmic process of the endothelial cell and reduction in luminal size were observed just after irradiation. After then, nuclear degeneration, marked proliferation of cytoplasmic process, thickened basal lamina, and numerous cytoplasmic vesicles were observed on the 1day after irradiation. These changes were recovered to normal on the 14days after 5Gy group, but not with 10Gy irradiation group. And destruction of endothelial cell and loss of basal lamina were not observed in both groups. 4. From the above results, reduction in luminal size, proliferation of cytoplasmic process and thickening of basal lamina were observed as the irradiation effects on the capillary and endothelial cell of the submandibular gland. And also, these changes may induce increase in capillary number and endothelial permeability by means of increase of cytoplasmic vesicle formation. The changes appeared earlier and more prominent in 10Gy irradiated group than in 5Gy irradiated group.
The purpose of this study was to observe the changes of the elemental transmission and bond strength between the metal and porcelain according to various kinds of ion beam mixing method. ion beam mixing of $meta1/SiO_2$ (silica), $meta1/Al_2O_3$(alumina) interfaces causes reactions when the $Ar^+$ was implanted into bilayer thin films using a 100KeV accelerator which was designed and constructed for this study. A vacuum evaporator used in the $10^{-5}-10^{-6}$ Torr vacuum states for the evaporation. For this study, three kinds of porcelain metal selected, -precious, semiprecious, and non-precious. Silica and alumina were deposited to the metal by the vacuum evaporator, separately. One group was treated by two kinds of dose of the ion beam mixing $(1\times10^{16}ions/cm^2,\;5\times10^{15}ions/cm^2)$, and the other group was not mixed, and analyzed the effects of ion beam mixing. The analyses of bond strength, elemental transmissions were performed by the electron spectroscopy of chemical analysis (ESCA), light and scanning electron microscope, scratch test, and micro Vickers hardness tests. The finding led to the following conclusions. 1. In the scanning electron and light microscopic views, ion beam mixed specimens showed the ion beam mixed indentation. 2. In the micro Vickers hardness and scratch tests, ion beam mixed specimens showed higher strength than that of non mixed specimens, however, nonprecious metal showed a little change in the bond strength between mixed and non mixed specimens. 3. In the scratch test, ion beam mixed specimens showed higher shear strength than that of non treated specimens at the precious and semiprecious groups. 4. In the ESCA analysis, Au-O and Au-Si compounds were formed and transmission of the Au peak was found ion beam mixed $SiO_2/Au$ specimen, simultaneously, in the higher and lower bonded areas, and ion beam mixed $SiO_2/Ni-Cr$ specimen, oxygen, that was transmitted from $SiO_2\;to\;SiO_2/Ni-Cr$ interface combined with 12% of Ni at the interface.
A total of nine Korean native kids and two Corriedale lambs, 1-20 days old, were each inoculated per os with a single dose of 2 × 107 oocysts of Cwptospori,mum muris (strain MCR) originated from mice to elucidate the kinetics and developmental stages of the coccidium in small ruminants. Irrespective of host's age, the prepatent period for both animals ranged from 19 to 35 days (28.1 days, on the average) and the patent period 16-85 days (47.8 days), and the total oocyst outputs showed enormous differences. Infection with greater numbers of oocyst outputs was not ordinarily established by transmission experiments. Oocysts discharged from the kids retained their infectivity by the mouse titration method. The immunogenicity of the coccidium and oocyst reproduction were proven by challenge infection and administration of prednisolone acetate. respectively. All the developmental stages of the coccidium in parasitophorous vacuoles were found by transmission electron microscopy in the pits of the gastric glands of a kid inoculated with oocysts and then necropsied on day 44 postinoculation. It indicated the full course of the host-parasite relationship in kids and lambs as well as mice.
In the present study, we used the microdialysis technique combined with high performance liquid chromatography (HPLC) and electrochemical detection to measure the extracellular levels of norepinephrine (NE) in the posterior hypothalamus in vivo, and to examine the effects of various drugs, affecting central noradrenergic transmission, on the extracellular concentration of NE in the posterior hypothalamus. Microdialysis probes were implanted stereotaxically into the posterior hypothalamus (coordinates: posterior 4.3 mm, lateral 0.5 mm, ventral 8 mm, relative to bregma and the brain surface, respectively) of rats, and dialysate collection began 2 hr after the implantation. The baseline level of monoamines in the dialysates were determined to be: NE $0.17{\pm}0.01,$ 3,4-dihydroxyphenylacetic acid (DOPAC) $0.94{\pm}0.07,$ homovanillic acid (HVA) $0.57{\pm}0.05$ pmol/sample (n=8). When the posterior hypothalamus was perfused with 90 mM potassium, maximum 555% increase of NE output was observed. Concomitantly, this treatment significantly decreased the output of DOPAC and HVA by 35% and 28%, respectively. Local application of imipramine $(50\;{\mu}M)$ enhanced the level of NE in the posterior hypothalamus (maximum 200%) compared to preperfusion control values. But, DOPAC and HVA outputs remained unchanged. Pargyline, an irreversible monoamine oxidase inhibitor, i.p. administered at a dose of 75 mg/kg, increased NE output (maximum 165%), while decreased DOPAC and HVA outputs (maximum 13 and 12%, respectively). These results indicate that NE in dialysate from the rat posterior hypothalamus were neuronal origin, and that manipulations which profoundly affected the levels of extracellular neurotransmitter had also effects on metabolite levels.
Kim, Youn-Jung;Song, Mi-Kyung;Sarma, Sailendra Nath;Choi, Han-Saem;Ryu, Jae-Chun
Molecular & Cellular Toxicology
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v.4
no.3
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pp.183-191
/
2008
Volatile organic compounds (VOCs) are common constituents of cleaning and degreasing agents, paints, pesticides, personal care products, gasoline and solvents. And VOCs are evaporated at room temperature and most of them exhibit acute and chronic toxicity to human. Benzene is the most widely used prototypical VOC and the toxic mechanisms of them are still unclear. The multi-step process of toxic mechanism can be more fully understood by characterizing gene expression changes induced in cells by toxicants. In this study, DNA microarray was used to monitor the expression levels of genes in HepG2 cells and HL-60 cells exposed to the benzene on IC20 and IC50 dose respectively. In the clustering analysis of gene expression profiles, although clusters of HepG2 and HL-60 cells by benzene were divided differently, expression pattern of many genes observed similarly. We identified 916 up-regulated genes and 1,144 down-regulated genes in HepG2 cells and also 1,002 up-regulated genes and 919 down-regulated genes in HL-60 cells. The gene ontology analysis on genes expressed by benzene in HepG2 and HL-60 cells, respectively, was performed. Thus, we found some principal pathways, such as, focal adhesion, gap junction and signaling pathway in HepG2 cells and toll-like receptor signaling pathway, MAPK signaling pathway, p53 signaling pathway and neuroactive ligand-receptor interaction in HL-60 cells. And we also found 16 up-regulated and 14 down-regulated commonly expressed total 30 genes that belong in the same biological process like inflammatory response, cell cycle arrest, cell migration, transmission of nerve impulse and cell motility in two cell lines. In conclusion, we suggest that this study is meaningful because these genes regarded as strong potential biomarkers of benzene independent of cell type.
Alzheimer's disease (AD) is the most prevalent form of neurodegenerative disease associated with aging in the human population. This disease is characterized by the following 4 structural changes : Atrophy of the Cortex, Parasympathetic, and other neural cells, the existence of Neurofibrillary tangles (NFTs), and the accumulation of Senile plaques. NFTs and Senile plaques is known to be the index of this disease. Senile plaques disturbs the neutro transmission and depletes of Acetylcholine. So, Recovery of Acetylcholine is the primal objective for treating Alzheimer's disease. So, Inhibiting the activity of Acetylcholine Esterase (AChE), which causes the hydrolysus of acetylcholine into choline and acetate, can be seen as a key role for treating Alzheimer's disease. Increasing body of evidence has been demonstrated that Bee Venom Acupuncture (BV) could compete with complex protein involving in multiple step of $NF-_{\kappa}B$ activation and exert the anti -inflammatory potential of combined inhibition of the prostanoid and nitric oxide synthesis systems by inhibition of IKK and $NF-_{\kappa}B$. The effect of BV through behavioral tests after memory impairment induced by Scopolamine. We examined the improving effect of BV on the Scopolamine (1 mg/Kg, i.p.)-induced memorial impairment using passive avoidance response and water maze tests in the mice. BV (0.84, $1.67\;{\mu}g/ml$) reversed the Scopolamine-induced memorial impairment in dose dependent manner. This study therefore suggests that BV acupuncture method may be useful for prevention of development or progression of AD.
Zhan, Yun-Hong;Liu, Jing;Qu, Xiu-Juan;Hou, Ke-Zuo;Wang, Ke-Feng;Liu, Yun-Peng;Wu, Bin
Asian Pacific Journal of Cancer Prevention
/
v.13
no.6
/
pp.2739-2744
/
2012
Background: Renal-cell carcinoma (RCC) is resistant to almost all chemotherapeutics and radiation therapy. ${\beta}$-Elemene, a promising anticancer drug extracted from a traditional Chinese medicine, has been shown to be effective against various tumors. In the present study, anti-tumor effects on RCC cells and the involved mechanisms were investigated. Methods: Human RCC 786-0 cells were treated with different concentrations of ${\beta}$-elemene, and cell viability and apoptosis were measured by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry, respectively. Protein expression was assayed by western blotting. Autophagy was evaluated by transmission electron microscopy. Results: ${\beta}$-Elemene inhibited the viability of 786-0 cells in a dose- and time-dependent manner. The anti-tumor effect was associated with induction of apoptosis. Further study showed that ${\beta}$-elemene inhibited the MAPK/ERK as well as PI3K/Akt/mTOR signalling pathways. Moreover, robust autophagy was observed in cells treated with ${\beta}$-elemene. Combined treatment of ${\beta}$-elemene with autophagy inhibitors 3-methyladenine or chlorochine significantly enhanced the anti-tumor effects. Conclusions: Our data provide first evidence that ${\beta}$-elemene can inhibit the proliferation of RCC 786-0 cells by inducing apoptosis as well as protective autophagy. The anti-tumor effect was associated with the inhibition of MAPK/ERK and PI3K/Akt/mTOR signalling pathway. Inhibition of autophagy might be a useful way to enhance the anti-tumor effect of ${\beta}$-elemene on 786-0 cells.
Ann, Xiao-Hua;Lun, Yong-Zhi;Zhang, Wei;Liu, Ben;Li, Xing-Yun;Zhong, Min-Tao;Wang, Xiao-Li;Cao, Jing;Ning, An-Hong;Huang, Min
Asian Pacific Journal of Cancer Prevention
/
v.15
no.12
/
pp.5055-5061
/
2014
In this study, an anti-oxidant and anti-tumor protein Latcripin-3 of Lentinula edodes C91-3 was expressed in Escherichia coli. for the first time. According to the cDNA library, the full-length gene of Latcripin-3 was cloned by the methods of 3'-full rapid amplification of cDNA Ends (RACE) and 5'-full RACE. The structural domain gene of Latcripin-3 was inserted into the pET32 a(+). The functional protein of Latcripin-3 was expressed in Rosetta-gami (DE3) E. coli, evaluated by Western blotting and mass spectrometry. DPPH testing showed that the protein Latcripin-3 can scavenge free radicals remarkably well. The activity of functional protein Latcripin-3 on A549 cells was studied with flow cytometry and the MTT method. The MTT assay results showed that there was a decreases in cell viability in a dose-dependent and time-dependent manner in protein Latcripin-3 treated groups. Flow cytometry demonstrated that Latcripin-3 can induce apoptosis and block S phase dramatically in human A549 lung cancer cells as compared to the control group. At the same time, the cell ultrastructure observed by transmission electron microscopy supported the results of flow cytometry. This research offers new insights and advantages for identifying anti-oxidant and anti-tumor proteins.
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