Journal of Physiology & Pathology in Korean Medicine
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v.17
no.5
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pp.1202-1207
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2003
In order to clarify the neuroprotective effect of Cornu Saigae Tataricae(CST) water extract on cultured mouse spinal motor neuron damaged by hydrogen peroxide (H₂O₂), MTT [3-(4,5-dimethylthiazole-2-yl)- 2,5-diphenyltetrazolium bromide] assay, LDH (Lactate Dehydrogenase) activity assay and SRB (Sulforhodamine B) assay were carried out after the cultured mouse spinal motor neuron were preincubated with various concentrations of CST water extract for 3 hours prior to exposure of hydrogen peroxide Cell viability of cultured mouse spinal motor neurons exposed to various concentrations of hydrogen peroxide for 6 hours was decreased in a dose-dependent manner. MTT50 values were 40 uM hydrogen peroxide. Cultured mouse spinal motor neurons in the medium containing various concentration of hydrogen peroxide for 6 hours showed increasing of LDH activity and decreasing of total protein synthesis. We know that hydrogen peroxide was toxic on cultured spinal motor neurons. Pretreatment of CST water extract for 3 hours following hydrogen peroxide prevented the hydrogen peroxide-induced neurotoxicity such as increasing of LDH activity and decreasing of total protein synthesis. These results suggest that hydrogen peroxide shows toxic effect on cultured spinal motor neurons and CST water extract is highly effective in protecting the neurotoxicity induced by hydrogen peroxide.
As the average life span have been lengthened and the rate of senile population have been raised, chronic degenerative diseases incident to aging has been increased rapidly and become a social problem. With this social background, recently, the facts that oxygen radicals(OR) have toxic effects on Central Nervous System and Peripheral Nervous System and cause neuropathy such as Parkinson's Disease, Alzheimer Disease have been turned out, and accordingly lots of studies on the mechanism of the toxic effects of OR on nerves, the diseases caused by OR and the approaches to curing the diseases have been made. The purpose of this study is to examine the toxic effects caused by Glucose Oxidase(GO) and the effects of herbal extracts such as Chilbokyeum(CBY), Chilbokyeumga Acori Rhizoma(CAR), Acori Rhizoma(AR) on the treatment of the toxic effects. For this purpose, experiments with the cultured cell from the cerebrums of new born mice were done. The results of these experiments were as follows. 1. GO, a oxygen radical, decreased the survival rate of the cultured cells on NR assay, MTT assay and amount of neurofilaments and increased the amount of total protein, lipid peroxidation and the amount of LDH. 2. CBY have efficacy of increasing the amount of neurofilaments and total protein and decreasing lipid peroxidation and the amount of LDH. 3. CAR have efficacy of increasing the amount of neurofilaments and total protein and decreasing lipid peroxidation and the amount of LDH. 4. AR have efficacy of increasing the amount of neurofilaments and total protein. From the above results, It is concluded that Chilbokyeumgamibang has marked efficacy as a treatment for the damages caused in the GO-mediated oxidative process. And Chilbokyeumgamibang is thought to have certain pharmacological effects on controlling over aging and treating Dementia. Further clinical study of this pharmacological effects of Chilbokyeumgamibang should be complemented.
Air suspedned particulates are the most serious factor among air pollutants in Seoul and their extracts have been revealed to be pulmonary carcinogenes. Air particulates were collected at a site representative of the high traffic area of Seoul from December 1993 to May 1994. Polycyclic aromatic hydrocarbons (PAHs) and nitroarenes in organic extracts of air particulates were determined by gas chromatography and mutagenicity of particle extracts was evaluated by the pre-incubation procedure with Salmonella typhirnurium TA98 and TA 98NR. The average concentration of total suspended particulates and inhalable (less than 10 $\mu$m) particulates were 169.63 $\mu g/m^3$, 141.92 $\mu g/m^3$, respectively. The relative contribution of organic matters was highest in neutral fraction and was lowest in basic fraction. Among identified 20 PAHs, the level of PAHs with 4-benzen ring i.e., pyrene, benzo(a)anthracene and chrysene were much higher than the PAHs with higher ring numbers. The mutagenicity of air particulates was much higher in the presence of rat liver microsomai fraction (S9 mixture) than that observed in its absence, which indicates that air particulates contained both direct and indirect mutagens. Nitroarenes in this study were not almost detected but mutagenicity of their fraction was higher. These results are represent to research for the identification of nitroarenes in the forward study.
Kim, Hyo-Rim;Son, Jung-Bin;Lim, Seung-Hyun;Kim, Jong-Sik
Journal of Life Science
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v.22
no.4
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pp.492-498
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2012
To investigate whether phytochemicals affect cancer cell viability, human colorectal HCT116 cells were treated with four different phytochemicals. Among these phytochemicals, curcumin is the strongest inhibitor of cell proliferation. In addition, it decreased cell viability in a dose-dependent manner. To unveil the molecular mechanisms involved in the inhibition of cell proliferation by curcumin, we carried out oligo DNA microarray analysis. We found that 137 genes were up-regulated more than 2-fold, and 141 genes were down-regulated more than 2-fold by 25 ${\mu}M$ curcumin treatment. Among the up-regulated genes, we selected 3 genes (ATF-3, GADD45A, and NR4A1) to confirm microarray data. The results of RT-PCR strongly agreed with those of the microarray data. Among the phytochemicals used in this study, curcumin is the strongest inducer of ATF3 expression, and increased ATF3 expression in a dose-dependent manner. Interestingly, FACS analysis showed that the inhibition of cell growth by curcumin was recovered by ATF3-siRNA transfection. Finally, we detected the changes of gene expression by ectopic expression of ATF3. The results indicated that many up-regulated genes were related to apoptosis. Overall, these results suggest that ATF3 may play an important role in the anti-proliferative activity of curcumin in human colorectal cancer cells.
Sharma, Chandra Mohan;Tiwari, Om Prakash;Rana, Yashwant Singh;Krishan, Ram;Mishra, Ashish Kumar
Journal of Forest and Environmental Science
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v.32
no.4
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pp.329-343
/
2016
The present study was conducted on ridge tops of moist temperate Oak forests in Garhwal Himalaya to assess the plant diversity, regeneration, biomass production and carbon assimilation in different Oak forests. For this purpose, three Oak forest types viz., (a) Quercus leucotrichophora or Banj Oak (FT1; between 1,428-2,578 m asl), (b) Quercus floribunda or Moru Oak (FT2; between 2,430-2,697 m asl) and (c) Quercus semecarpifolia or Kharsu Oak (FT3; between 2,418-3,540 m asl) were selected on different ridge tops in Bhagirathi catchment area of Garhwal Himalaya. A total of 91 plant species including 23 trees (8 gymnosperms and 15 angiosperms), 21 shrubs and 47 herbs species belonging to 46 families were recorded from all the ridge top Oak forests. The highest mean tree density ($607{\pm}33.60trees\;ha^{-1}$) was observed in Q. floribunda forest with lower mean total basal cover (TBC) value ($48.02{\pm}3.67m^2ha^{-1}$), whereas highest TBC value ($80.16{\pm}3.30m^2ha^{-1}$) was recorded for Q. semecarpifolia forest, with lowest mean stem density ($594{\pm}23.43stems\;ha^{-1}$). The total biomass density (TBD) across three Oak forests ranged between $497.32{\pm}83.70$ (FT1) and $663.16{\pm}93.85t\;ha^{-1}$ (FT3), while the total carbon density (TCD) values ranged between $228.75{\pm}22.27$ (FT1) and $304.31{\pm}18.12t\;ha^{-1}$ (FT3). Most of the tree species were found with good regeneration (GR) status (average 45%) in all the forest types whereas, few species were found not regenerating (NR) (average 17%) however, few new recruitments were also recorded. ANOVA (Post-Hoc Tukey's test at 5% significance level) indicated significant forest-wise differences in TBC, TBD and TCD (in tree layer); family and evenness (in shrub layer only) values, while insignificant differences were noticed in density values of tree, seedling and herb layer.
The Journal of Korean Academic Society of Nursing Education
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v.6
no.2
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pp.186-198
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2000
The purpose of this study was to investigate the factors and the degree of nursing college student's clinical practice satisfaction. The sample consisted of 488 nursing students who had been in the clinical practice experience from 6 junior nursing colleges in Korea. Data for this study was collected from 20 May to 20 June, 2000. Data were analysed by SPSS/PC using frequency, percentage, mean, standard deviation, T-test, one-way ANOVA, and regression. The results of this study are as follows : 1. The highest motive of selecting a nursing science came to be 'having a good prospect for getting a job' (29.3%), major place of the clinical nursing practice was university hospital(46.5%), and the degree of satisfaction about the nursing science was 'relatively satisfied' (43%). 2.The fields that the highest satisfaction of the nursing student's clinical practice were DR(3.25), NR(3.18), ICU(3.11), and OR(3.10). The highest rank of the nursing student's clinical practice satisfaction was 'feels more continuous nursing studying is required after getting a job or pass the RN exam'(4.24). 3. There was significant value between the Grade(2yr, 3yr) and the satisfaction of the clinical practice environment(p<0.001), the clinical practice interpersonal relationship (p<0.001), the clinical practice evaluation (p<0.05), and there was significant value between the satisfaction about the nursing science and the satisfaction of the clinical practice environment(p<0.001), the clinical practice interpersonal relation ship (p<0.05), the satisfation after the clinical practice(p<0.001). 4. There was significant value between 'the opinion of the clinical practice periods' and the satisfaction of the clinical practice place(p<0.05), the clinical practice environment(p<0.001), the clinical practice interpersonal relationship(p<0.001), the satisfation after the clinical practice(p<0.001). 5.The satisfaction of the clinical practice interpersonal relationship influenced on the nursing student's clinical practice satisfaction($R^{2}=.188$). From these results, it is suggested that the higher the satisfaction of the clinical practice interpersonal relationship be like to improve the nursing college student's clinical practice satisfaction.
Kim, Jong-Ho;Jeong, Han-Seong;Park, Jong-Seong;Kim, Jong-Keun;Park, Sah-Hoon
The Korean Journal of Physiology and Pharmacology
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v.2
no.1
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pp.9-19
/
1998
The present study was primarily carried out to characterize the properties of the spinomesencephalic tract (SMT) neurons that project from the upper cervical spinal segments to the midbrain. It was also investigated whether these neurons received convergent afferent inputs from other sources in addition to cervical inputs. Extracellular single unit recordings were made from neurons antidromically activated by stimulation of midbrain. Recording sites were located in lamina $I{\sim}VIII\;of\;C1{\sim}C3$ segments of spinal cord. Receptive field (RF) and response properties to mechanical stimulation were studied in 71 SMT neurons. Response profiles were classified into six groups: complex (Comp, n=9), wide dynamic range (WDR, n=16), low threshold (LT, n=5), high threshold (HT, n=6), deep/tap (Deep, n=10), and non- responsive (NR, n=25). Distributions of stimulation and recording sites were not significantly different between SMT groups classified upon their locations and/or response profiles. Mean conduction velocity of SMT neurons was $16.7{\pm}1.28\;m/sec$. Conduction velocities of SMTs recorded in superficial dorsal horn (SDH, n=15) were significantly slower than those of SMTs recorded in deep dorsal horn (DDH, n=18), lateral reticulated area (LRA, n=21), and intermediate zone and ventral horn (IZ/VH, n=15). Somatic RFs for SMTs in LRA and IZ/VH were significantly larger than those in SDH and DDH. Five SMT units (4 Comps and 1 HT) had inhibitory somatic RFs. About half (25/46) of SMT units have their RFs over trigeminal dermatome. Excitabilities of 5/12 cells and 9/13 cells were modulated by stimulation of ipsilateral phrenic nerve and vagus nerve, respectively. These results suggest that upper cervical SMT neurons are heterogenous in their function by showing a wide range of variety in location within the spinal gray matter, in response profile, and in convergent afferent input.
Journal of the Korean Institute of Traditional Landscape Architecture
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v.36
no.3
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pp.100-114
/
2018
Nationally designated Cultural Properties 'Scenic site No.12 Maisan Mountain, Jinan' designated areas and some protected areas, and taking into account the dynamics of naturalized plants causing problems, we will restore the original vegetation scenery of Mt. Maisan. The results of this study are as follows. A total of 76 families, 192 genera, 286 taxa, and inland and inhabited areas, 76 and 138 genera and 163 taxa were identified in the areas of Ammaibong. The total number of naturalized plants identified in this study area is 28 taxa total, which corresponds to 7.1% naturalization rate(NR) among the vascular plants of all 395 taxa, and the urbanization index(UI) corresponds to 8.4% of the 333 taxa of Korean naturalized plants. Ecosystem disturbance plants identified in the survey area were Ambrosia artemisiifolia 1 taxa. The naturalized plants controlled and managed by separate anthropogenic vegetation management within the designation and protection area of Maisan scenic place are three species of herbaceous Rumex acetosella, A. artemisiifolia and Festuca arundinacea. It was identified as a breed. Indigofera bungeana and F. arundinacea communities around the stairway and Amorpha fruticosa, I. bungeana, A. artemisiifolia and Amaranthus patulus of the top of Am-Maibong were selected as the first priority sites for exclusion of exotic species in Maisan area and target naturalized plants species to the Ammaibong peak. In addition, R. acetosella community around the temple was suggested to be removed first to preserve endemic species. For the restoration of vegetation, we suggest that Stephanandra incisa, Spiraea blumei, Weigela subsessilis, etc. should be planted after removal of I. bungeana, and F. arundinacea, C. lanceolata, Carex callitrichos var. nana.
This study is a descriptive comparative study to identify personal characteristics and nursing work characteristics according to the presence or absence of back pain of nurses in intensive care units in general hospitals and to explore major factors that affect back pain induction. A survey was conducted on nurses in the intensive care unit of a general hospital located in D City, and a total of 100 copies were used for analysis. For data analysis, descriptive statistics, chi-square test, Fisher accurate test, and logistic regression analysis were performed using IBM SPSS 24.0. The study found that 69% of intensive care unit nurses had back pain, 65.2% of which experienced back pain for more than three months in the past year, and 84.1% had back pain after working in the intensive care unit. In the back pain intensity score measured by NRS, 49% answered that they experienced 4 or more points. As factors related to back pain, gender (p=.03) were significant variables in personal characteristics, in the characteristics of nursing work, the number of patient assistance (p=.03) and the number of patient exchanges (p=.01), heavy lifting (p=.04), satisfaction with the condition of the shoes (p=<.001) was found to be a significant variable affecting back pain induction. It is considered that hospital organization and national policies are needed to prevent and manage low back pain in intensive care unit nurses.
A universal DNA barcoding for agricultural noxious weeds is a powerful technique for species identification without morphological knowledge, by using short sections of DNA from a specific region of the genome. Two standard barcode markers, chloroplast rbcL and matK, and a supplementary nuclear ribosomal Internal Transcribed Spacer (ITS) region were used to examine the effectiveness of the markers for Pooideae barcoding using 163 individuals of 29 taxa across 16 genera of Korean Pooideae. The rbcL and ITS revealed a good level of amplification and sequencing success while matK did not. Barcode gaps were 78.6% for rbcL, 96.2% for matK, and 91.7% for ITS, respectively. Resolving powers were 89.3% for rbcL, 92.3% for matK, and 79.1% for ITS. The matK obtained the best both barcode gap and resolving power. However, it should be considered not to employ matK for Pooideae barcode because of low rate of PCR amplification and sequencing success. As a single DNA marker, rbcL and ITS were reasonable for Pooideae barcode. Barcode gap and resolving power were increased when ITS was incorporated into the rbcL. The barcode sequences were deposited to the National Center for Biotechnology Information (NCBI) database for public use.
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