• Title/Summary/Keyword: $S_N1$ mechanism

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Management of Patients with Rib Fractures: Analysis of the Risk Factors Affecting the Outcome (늑골골절 환자 치료: 결과에 영향을 주는 위험인자 분석)

  • Kim, Han-Yong;Kim, Myoung-Young
    • Journal of Chest Surgery
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    • v.43 no.3
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    • pp.285-291
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    • 2010
  • Background: Thoracic trauma is one of the leading causes of morbidity and mortality in developing countries. A rib fracture that is secondary to blunt thoracic trauma is an important indicator of the severity of the trauma. The purpose of study was to determine the morbidity and mortality rates and the management of rib fractures. Material and Method: We performed a retrospective study that involved all the blunt trauma patients with rib fractures, excluding those that were transferred to other hospital within 3 days, that were seen at our hospital between May 2002 and December 2008. Of the 474 admitted patients, 454 met the inclusion criteria. There were 356 male and 98 females, and their overall mean age was 53 years (range: 5~90 years). The outcome parameters included the mechanism of injury, the number of fractured ribs, the length of stay in the ICU, the Injury Severity Score (ISS), the length of the hospital stay, the pulmonary complications and the mortality. Result: The mechanism of trauma included traffic accidents in 189 (41.7%) cases, slipping down in 103 (22.7%) cases, falls in 85 (18.7%) cases, cultivator accidents in 30 (6.6%) cases, industrial accidents in 32 (7.0%) cases and assault in 15 (3.3%) cases. Intrathoracic injury was noted such as hemothorax in 269 (59.3%) cases, pneumothorax in 144 (31.7%) cases, pulmonary contusion in 95 (20.9%) cases, subcutaneous emphysema in 29 (6.4%) cases and great vessel injury in 5 (0.1%) cases. Conservative treatment was administered to most of the patients. Tube thoracostomy was administered in 234 (51.5%) cases, whereas thoracotomy was performed in 18 (4.0%) cases. The mean duration of thoracostomy was $5.2{\pm}6.2$ days. Most of the cases with rib fracture were treated in wards and their mean duration of hospital stay was $22.5{\pm}20$ days. The mean Injury Severity Score (ISS) was $14.8{\pm}10.9$ (range: 3~75). The mortality rate was calculated to be 4.8% (n=22). The main factors correlated with an adverse outcome were the number of ribs fractured, the duration of thoracostomy and pulmonary disease. Industrial insurance affected the length of hospitalization. Pulmonary contusion and the Injury Severity Score (ISS) affected the mortality. Conclusion: Rib fractures are a indicator of severe injury. Because of the complication and associated injuries, we believe these patients should be admitted for evaluation and treatment. Recent studies on the impact of rib fractures after blunt trauma have shown that patients as young as 40 years of age demonstrate increased morbidity and mortality with similar injuries as compared to that of older patients. The ISS and pulmonary contusion influenced the mortality rate. Patients with isolated rib fractures should be hospitalized if the number of fractured ribs is one or more.

Prolactin Response to Cimetidine in the Schizophrenics - In Unmedicated Male Positive and Negative Patients - (정신분열증 환자에서 Cimetidine에 의한 Prolactin 분비 반응 - 양성 및 음성 아형 남자 환자에서 -)

  • Jin, Hyuk Hee;Kwon, Young Joon;Jeong, Hee Yeon;Han, Sun Ho
    • Korean Journal of Biological Psychiatry
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    • v.3 no.1
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    • pp.121-126
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    • 1996
  • Objects : There is considerable interest in the role of serotonin(5-HT) in the pathophysiology of schizophrenia. Cimetidine, $H_2$ antagonist, produces transient increase in serum prolactin(PRL) levels by indirect serotonergic mechanism in man following intravenous administration. Therefore the authors investigated the effects of cimetidine on serum PRL levels of male unmedicated schizophrenics. Method : Baseline serum prolactin level and psychopathology were measured at 9:00 AM. in the two groups(12 positive schizophrenics, 7 negative schizophrenics) and $T_{30}$ levels were measured 30 minutes after intravenous injection of cimetidine (ie, 9:30 AM) Results: 1) Baseline prolactin levels were not different in the three groups. 2) Prolactin levels of 30 minutes after intravenous injection of cimetidine($T_{30}$) compared with baseline prolactin levels were increased all in the three groups. 3) Degrees of interval change from baseline to $T_{30}$ were significantly different between normal control and negative schizophrenics(p<0.05). Conclusion : The prolactin response to cimetidine was significantly blunted in negative male schizophrenics than normal control. These data are consistent with the hypothesis of an abnormality of serotonergic activity, including down-regulation $5-HT_2$ receptors, in male negative schizophrenics.

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Fluoride Sorption Property of Lanthanum Hydroxide (란탄수산화물의 불소 흡착 특성)

  • Kim, Jung-Hwan;Park, Hyun-Ju;Jung, Kyung-Hun
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.7
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    • pp.714-721
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    • 2010
  • This research was undertaken to evaluate the feasibility of lanthanum hydroxide for fluoride removal from aqueous solutions. A batch sorption experiments were conducted to study the influence of various factors such as pH, contact time, initial fluoride concentration and temperature on the sorption of fluoride on lanthanum hydroxide. The optimum fluoride removal was observed in the $pH_{eq}{\leq}8.8$. Sorption equilibrium of fluoride on lanthanum hydroxide was better described by the Freundlish isotherm model than by the Langmuir isotherm model. The adsorption energy obtained from D-R model was 9.21 kJ/mol indicating an ion-exchange process as primary adsorption mechanism. The pseudo-second-order kinetic model described well the experimental kinetic data. Thermodynamic parameters such as ${\Delta}Go^{\circ}$, ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ indicated that the nature of fluoride sorption is spontaneous and endothermic. The used lanthanum hydroxide could be regenerated by washing with NaOH solution. Also, the results applied to real ground water indicate that fluoride selectivity and removal capacity of lanthanum hydroxide were superior to those of PA anion-exchange resin.

Evaluation of Natural Attenuation by Addition of Fumarate as Carbon Source and Gene Analysis in Groundwater Sample (지하수 중 탄소원으로 fumarate 주입과 유전자분석을 통한 질산성질소 자연저감도 평가)

  • Park, Sunhwa;Kim, Hyun-Gu;Kim, Sohyun;Lee, Min-Kyeong;Lee, Gyeong-Mi;Kim, Young;Kim, Moon-Su;Kim, Taeseung
    • Journal of Soil and Groundwater Environment
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    • v.19 no.4
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    • pp.62-69
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    • 2014
  • In the results of monitoring nitrate concentration in more than 8,000 groundwater wells around agro-livestock, the average and maximum nitrate concentration was 9.4 mg/L and 101.2 mg/L, respectively. Since about 31% of the monitoring wells was exceed the quality standard for drinking water, nitrate control such as remediation or source regulation is required to conserve safe-groundwater in South Korea. Typical nitrate-treatment technologies include ion exchange, reverse osmosis, and biological denitrification. Among the treatment methods, biological denitrification by indigenous microorganism has environmental and economic advantages for the complete elimination of nitrate because of lower operating costs compared to other methods. Major mechanism of the process is microbial reduction of nitrate to nitrite and nitrogen gas. Three functional genes (nosZ, nirK, nirS) that encode for the enzyme involved in the pathway. In this work, we tried to develop simple process to determine possibility of natural denitrification reaction by monitoring the functional gene. For the work, the functional genes in nitrate-contaminated groundwater were monitored by using PCR with specific target primers. In the result, functional genes (nosZ and nirK) encoding denitrification enzymes were detected in the groundwater samples. This method can help to determine the possibility of natural-nitrate degradation in target groundwater wells without multiplex experimental process. In addition, for field-remediation application we selected nitrate-contaminated site where 200~600 mg/L of nitrate is continuously detected. To determine the possibility of nitrate-degradation by stimulated-natural attenuation, groundwater was sampled in two different wells of the site and nitrate concentration of the samples was 300 mg/L and 616 mg/L, respectively. Fumarate for different C/N ratio was added into microcosm bottles containing the groundwater to examine denitrification rate depending on carbon concentration. In the result, once 1.5 times more than amount of fumarate stoichiometry required was added, the 616 mg/L of nitrate and 300 mg/L of nitrate were completely degraded in 8 days and 30 days. The nitrite, byproduct of denitrification process, was also completely degraded during the experimental period.

Anti-inflammatory effect of a mixture of Astragalus membranaceus and Lithospermum erythrorhizon extracts by inhibition of MAPK and NF-κB signaling pathways in RAW264.7 cells (RAW264.7 대식세포에서 MAPK 및 NF-κB 신호전달 경로 억제를 통한 황기 및 지치 복합물의 항염증 효과)

  • Choi, Doo Jin;Kim, Geum Soog;Choi, Bo-Ram;Lee, Young-Seob;Han, Kyung Sook;Lee, Dong-Sung;Lee, Dae Young
    • Journal of Applied Biological Chemistry
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    • v.63 no.4
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    • pp.421-428
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    • 2020
  • This study investigated a mixture of Astragalus membranaceus (AM) and Lithospermum erythrorhizon (LE) extracts (ALM16), exerts anti-inflammatory effects in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells, and its underlying mechanism. ALM16 was prepared by mixing AM and LE extracts in a ratio of 7:3 (w/w). Cytotoxicity of ALM16 in RAW264.7 cells was not shown up to 200 ㎍/mL of ALM16. The results of this study showed that ALM16 does-dependently inhibits the production of nitric oxide, prostaglandin E2 and pro-inflammatory cytokines (interleukin-1β, interleukin-6, and tumor necrosis factor-α) in LPS-induced RAW264.7 cells. ALM16 not only markedly reduced the protein expression levels of inducible nitric oxide synthase and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW264.7 cells, but also inhibited the nuclear translocation and DNA-binding activity of nuclear factor-kappa B (NF-κB). In addition, ALM16 specifically inhibited the phosphorylation of c-Jun N-terminal kinase and extracellular signal-regulated kinases in LPS-stimulated RAW264.7 cells. In conclusion, these results suggest that ALM16 may exert anti-inflammatory effect by modulating mitogen-activated protein kinase and NF-κB signaling pathways.

Expression of TIMP1, TIMP2 Genes by Ionizing Radiation (이온화 방사선에 의한 TIMP1, TIMP2 유전자 발현 측정)

  • Park Kun-Koo;Jin Jung Sun;Park Ki Yong;Lee Yun Hee;Kim Sang Yoon;Noh Young Ju;Ahn Seung Do;Kim Jong Hoon;Choi Eun Kyung;Chang Hyesook
    • Radiation Oncology Journal
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    • v.19 no.2
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    • pp.171-180
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    • 2001
  • Purpose : Expression of TIMP, intrinsic inhibitor of MMP, is regulated by signal transduction in response to genotoxins and is likely to be an important step in metastasis, angiogenesis and wound healing after ionizing radiation. Therefore, we studied radiation mediated TIMP expression and its mechanism in head and neck cancer cell lines. Materials and Methods : Human head and neck cancer cell lines established at Asan Medical Center were used and radiosensitivity $(D_0)$, radiation cytotoxicity and metastatic potential were measured by clonogenic assay, n assay and invasion assay, respectively. The conditioned medium was prepared at 24 hours and 48 hours after 2 Gy and 10 Gy irradiation and expression of TIMP protein was measured by Elisa assay with specific antibodies against human TIMP. hTIMP1 promoter region was cloned and TIMP1 luciferase reporter vector was constructed. The reporter vector was transfected to AMC-HN-1 and -HN-9 cells with or without expression vector Ras, then the cells were exposed to radiation or PMA, PKC activator. EMSA was peformed with oligonucleotide (-59/-53 element and SP1) of TIMP1 promoter. Results : $D_0$ of HN-1, -2, -3, -5 and -9 cell lines were 1.55 Gy, 1.8 Gy, 1.5 Gt, 1.55 Gy and 2.45 Gy respectively. n assay confirmed cell viability, over $94\%$ at 24hrs, 48hrs after 2 Gy irradiation and over 73% after 10 Gy irradiation. Elisa assay confirmed that cells secreted TIMP1, 2 proteins continuously. After 2 Gy irradiation, TIMP2 secretion was decreased at 24hrs in HN-1 and HN-9 cell lines but after 10 Gy irradiation, it was increased in all cell lines. At 48hrs after irradiation, it was increased in HN-1 but decreased in HN-9 cells. But the change in TIMP secretion by RT was mild. The transcription of TIMP1 gene in HN-1 was induced by PMA but in HN-9 cell lines, it was suppressed. Wild type Ras induced the TIMP-1 transcription by 20 fold and 4 fold in HN-1 and HN-9 respectively. The binding activity to -59/-53, AP1 motif was increased by RT, but not to SP1 motif in both cell lines. Conclusions : We observed the difference of expression and activity of TIMPs between radiosensitive and radioresistant cell line and the different signal transduction pathway between in these cell lines may contribute the different radiosensitivity. Further research to investigate the radiation response and its signal pathway of TIMPs is needed.

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Effects of Crataegii fructus on the Contractile Response of Rabbit Corpus Cavernosum (산사(山査)가 토끼 음경해면체의 수축에 미치는 영향)

  • Lee, Han Seok;Park, Sun Young
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.5
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    • pp.602-610
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    • 2013
  • This study was aimed to evaluate the cavernosal relaxation effect of Crataegii fructus(CF) in the contracted rabbit penile corpus cavernosum by agonists.In order to study the effect of CF on the vasoconstriction of rabbit penile corpus cavernosum, isolated rabbit penile corpus cavernosum tissues were used for the experiment using organ baths containing Krebs solution.To investigate the cavernosal relaxation of CF, CF extract at $0.01{\sim}3.0mg/m{\ell}$ was added after penile corpus cavernosum were contracted by norepinephrine(NE) $1{\mu}M$. To analyze the mechanism of CF's vasorelaxation, CF extract infused into contracted penile tissues by NE after each treatment of indomethacin(IM), $N{\omega}$-nitro-L-arginine(L-NNA), methylene blue(MB), tetraethylammonium chloride(TEA).To study the effect of CF on influx of extracellular calcium chloride($Ca^{2+}$) in penile tissues, in $Ca^{2+}$-free krebs solution, $Ca^{2+}$ 1 mM infused into contracted penile tissues by NE after pretreatment of CF. Cytotoxic activity of CF on human umbilical vein endothelial cell(HUVEC) was measured by MTT assay, and nitric oxide(NO) prodution was measured by Griess reagent. CF relaxed cavernosal strip with endothelium contracted by NE, but in the strips without endothelium, CF-induced relaxation was significantly inhibited. The pretreatment of L-NNA, MB, TEA decreased significantly on the cavernosal relaxation than not-treatment of them. But the pretreatment of IM had no significant effect on the cavernosal relaxation. In $Ca^{2+}$-free krebs solution, when $Ca^{2+}$ infused into contracted penile tissues by NE, pretreatment of CF inhibit contraction induced by adding $Ca^{2+}$.NO production wasn't increased by treatment of CF on HUVEC. This findings showed that CF is effective for the relaxation of rabbit penile corpus cavernosum, and we suggest that CF relax rabbit corpus cavernosal smooth muscle through multiple action mechanisms that include increasing the release of nitric oxide from corporal sinusoidal endothelium, inhibition of $Ca^{2+}$ mobilization into cytosol from the extracellular fluid, and maybe a hyperpolarizing action.

Trace impurity analysis of Cu films using GDMS: concentration change of impurities by applying negative substrate bias voltage (글로우방전 질량분석법을 이용한 구리 박막내의 미량불순물 분석: 음의 기판 바이어스에 의한 불순물원소의 농도변화)

  • Lim Jae-Won;Isshiki Minoru
    • Journal of the Korean Vacuum Society
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    • v.14 no.1
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    • pp.17-23
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    • 2005
  • Glow discharge mass spectrometry(GDMS) was used to determine the impurity concentrations of the deposited Cu films and the 6N Cu target. Cu films were deposited on Si (100) substrates at zero substrate bias voltage and a substrate bias voltage of -50 V using a non-mass separated ion beam deposition method. Since do GDMS has a little difficulty to apply to thin films because of the accompanying non-conducting substrate, we have used an aluminum foil to cover the edge of the Cu film in order to make an electrical contact of the Cu film deposited on the non-conducting substrate. As a result, the Cu film deposited at the substrate bias voltage of -50 V showed lower impurity contents than the Cu film deposited without the substrate bias voltage although both the Cu films were contaminated during the deposition. It was found that the concentration change of each impurity in the Cu films by applying the negative substrate bias voltage is related to the difference in their ionization potentials. The purification effect by applying the negative substrate bias voltage might result from the following reasons: 1) Penning ionization and an ionization mechanism proposed in the present study, 2) difference in the kinetic energy of accelerated Cu+ ions toward the substrate with/without the negative substrate bias voltage.

Mechanisms of Tolerance to Diphenyl Ether Herbicide Oxyfluorfen in Rice Cultivars (Diphenyl Ether계 제초제 Oxyfluorfen에 대한 벼 품종간 저항성기구)

  • Choi, S.H.;Kim, N.Y.;Lee, J.J.
    • Korean Journal of Weed Science
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    • v.16 no.4
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    • pp.362-371
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    • 1996
  • In this study, the relationships between sensitivity to oxyfluorfen, absorption of the herbicide, protoporphyrin IX(Proto IX) accumulation and activities of antioxidative enzymes were examined to identify the tolerance mechanism against oxyfluorfen in various rice cultivars having different level of tolerance to this herbicide. Absorption of oxyfluorfen in tolerant rice cultivars was slower than in susceptible cultivars. Proto IX accumulation in various rice cultivars treated with oxyfluorfen was higher in susceptible cultivars than in tolerant ones. In susceptible cultivars especially, Proto IX accumlated rapidly during the herbicide treatment in the dark. Large amounts of Proto IX accumulation were considered to cause membrane lipid peroxidation in the light. However, among the tested rice cultivars, there was little relationship between their tolerance to oxyfluorfen and the activities of antioxidative enzymes. Therefore, it is assumed that differential susceptibility of rice cultivars to oxyfluorfen was due to difference in their capability to absorb the herbicide and to subsequently accumulate Proto IX.

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Analyses of Widely Used Design Codes for Pile Foundation Using the t-z Method (t-z 방법을 이용한 말뚝기초 설계기준별 비교분석)

  • Park, Sungwon;Misra, Anil
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.10
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    • pp.33-42
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    • 2012
  • The efficiency of the current design methods for computing pile resistances is analyzed using field load-settlement tests results. Twelve load-settlement test data for drilled shafts and bored piles were obtained from the literature. These load-test data were fitted using the t-z method. Subsequently, the ultimate resistances were evaluated based upon the failure criteria from following methods: (1) the Davisson's approach and (2) settlement corresponding to 5% or 10% shaft diameter approach. The ultimate resistances for these drilled shafts and bored piles were also predicted using methods based on the design code from North America (United States, Canada), Europe, and Asia (Japan). The pile resistances determined from field load-settlement tests were compared with those calculated using the design codes. The comparisons show that most design codes predict a conservative resistance for drilled shafts and bored piles. However, in the case of drilled shafts, we find that some of the design codes can over-predict the resistance and, therefore, should be applied cautiously. This research also shows that the t-z method can be successfully used to predict the ultimate resistance and the load transfer mechanism for a single pile.