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Study on Present Status of Poultry Farming and Improvement of Technical Management for Poultry Production (양계농가실태와 생산경영기술 개선에 관한 조사연구)

  • 오세정
    • Korean Journal of Poultry Science
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    • v.8 no.2
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    • pp.91-114
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    • 1981
  • This research was carried out from July to August, 1981, to analyse the true state of management, the skill of production, the structure of consciousness about the selected 294 poultry$.$farms, and to know about their bottlenecks and suggestions. The results obtained were as follows: 1. As for manager's ages, 31 to 45 years old men rate was 67.76%. upper 50years old men 15.94%. 2. 79.9% of farm omen possess attainments equal to or higher than those of upper secondary school graduates. 3. In poultry farming career of the investigated person, layer chicken industry was longer than broiler. 4. Occupations of farm owners before. doing poultry farming were farmers(32.35%), company employees, civil servants and soldiers, etc. 5. 58.62% of the person ran only poultry farming and the rest of them held the additional office of a farmer and a public officer. 6. There were many people who made a speciality of poultry farming holding additional jobs as dairy farming, cultivating crops, gardening, etc. 7. 42.35% of the person began poultry farming with under 1,000 layer chickens. And the rate of the ones with 1,000-2,000 broilers for the first time consisted 40.95% 8. Present breeding scale was that the rate of the farmers having 5,000-10,000 layer chickens was 37.13% and the ones having 5,000-10,000 broilers 38.32%. 9. The rate of the person supplying self-labor was 23.16%, the person having 1.3 employees 51.47% and the ones having under 20 employees 1.47%. 10. 74.26% of the poultry farms used very good quality of baby chicks. 11. The rate of the farms which used chicken feed making the point of the quality of it was 65.47% and the ones which bought it on credit 26.62%. 12. 65.47% bought feed directly from factories and 26.62% bought it from commercial agents. 13. The rate of the layer chicken farms paying for feed in cash was 19.39% and the broiler farms 32.74%. Most of the farms bought feed on credit by 30-60 days. 14. They bought the medicine for chicken from animal drug stores or veterinary hospitals. 15. The rate of the person posting up accounts roughly was 47.52% and that of the ones doing them detaily was 43.57%, 40% did not do them because of bother and only 21.22% had their own cashbooks.

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Craniofacial morphologic alteration induced by bone-targeted mutants of FGFR2 causing Apert and Crouzon syndrome (어퍼트 및 크루즌 증후군을 유발하는 골조직 특이성 FGFR2 돌연변이에 의한 두개안면 형태의 변화)

  • Lee, Kee-Joon;Nah, Hyun-Duck;Tjoa, Stephen T. J.;Park, Young-Chel;Baik, Hyoung-Seon;Yun, Tae-Min;Song, Jin-Wook
    • The korean journal of orthodontics
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    • v.36 no.4
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    • pp.284-294
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    • 2006
  • Objective: Activating mutations in the fibroblast growth factor receptor-2 (FGFR2) have been shown to cause syndromic craniosynostosis such as Apert and Crouzon syndromes. The purpose of this pilot study was to investigate the resultant phenotypes induced by the two distinctive bone-targeted gene constructs of FGFR2, Pro253Arg and Cys278Phe, corresponding to human Apert and Crouzon syndromes respectively. Methods: Wild type and a transgenic mouse model with normal FGFR2 were used as controls to examine the validity of the microinjection. Micro-CT and morphometric analysis on the skull revealed the following results. Results: Both Apert and Crouzon mutants of FGFR2 induced fusion of calvarial sutures and anteroposteriorly constricted facial dimension, with anterior crossbite present only in Apert mice. Apert mice differed from Crouzon mice and transgenic mice with normal FGFR2 in the anterior cranial base flexure and calvarial flexure angle which implies a possible difference in the pathogenesis of the two mutations. In contrast, the transgenic mice with normal FGFR2 displayed normal craniofacial phenotype. Conclusion: Apert and Crouzon mutations appear to lead to genotype-specific phenotypes, possibly causing the distinctive sites and sequence of synostosis in the calvaria and cranial base. The exact function of the altered FGFR2 at each suture needs further investigation.

Questions and Answers about the Humidifier Disinfectant Disaster as of February 2017 (가습기살균제 참사의 진행과 교훈(Q&A))

  • Choi, Yeyong
    • Journal of Environmental Health Sciences
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    • v.43 no.1
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    • pp.1-22
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    • 2017
  • 'The worstest environment disaster', 'World's first biocide massacre', 'Home-based Sewol ferry disaster' are all phrases attached to the recent humidifier disinfectant disaster. In the spring of 2011, four of 8 pregnant women including 1 adult man passed away at a university hospital in Seoul due to breathing failure. Epidemiologic investigation conducted by the Korean CDC soon revealed the inhalation of humidifier disinfectant, which had been widely used in Korea during the winter, to be responsible for the disease. As well as lung fibrosis hardening of the lungs, other diseases including asthma, rhinitis, skin disease, liver disease, fetal disease or cancers have been researched for their relation with exposure to the products. By February 9, 2017, 5,342 cases had registered for health problems and 1,131 of them were already dead (20.8% mortality rate). Based on studies by government agencies and a telephone survey of the general population by Seoul National University and civic groups, around 20% of the general public of Korea has used these products. Since the market release of the first product by SK Chemical in 1994, over 7.1 million items from around 20 brands were sold up to 2011. Most of the products were manufactured by well-known large conglomerates such as SK, Lotte, Samsung, Shinsegye, LG, and GS, as well as some European companies including UK-based Reckitt Benckiser and TESCO, the German firm Henkel, the Danish firm KeTox, and an Irish company. Even though this disaster was unveiled in 2011 by the Korean government, the issue of the victims was neglected for over five years. In 2016, an unexpected but intensive investigation by prosecutors found that Reckitt Benckiser manipulated and concealed animal tests for its own brand and brought several university experts and company employees to court. The matter was an intense social issue in Korea from May to June with a surge in media coverage. The prosecutor's investigation and a nationwide boycott campaign organized by victims and environmental groups against Reckitt Benckiser, whose product had been used by more than 70% of victims, led to the producer's official apology and a compensation scheme. A legislative investigation organized after the April 2016 national election revealed the producers' faults and the government's responsibility, but failed to meet expectations. A special law for the victims passed the National Assembly in January 2017 and a punitive system together with a massive environmental epidemiology investigation are expected to be the only solutions for this tragedy. Sciences of medicine, toxicology and environmental health have provided decisive evidence so far, but for the remaining problems the perspectives of social sciences such as sociology and jurisprudence are highly necessary, similar to with the Minamata disease and Wonjin Rayon events. It may not be easy to follow this issue using unfamiliar terminology from medical and chemical science and the long, complicated history of the event. For these reasons the author has attempted to write this article in a question and answer format to render it easier to follow. The 17 questions are: Q1 What is humidifier disinfectant? Q2 What kind of health problems are caused by humidifier disinfectant? Q3 How many victims are there? Q4 What is the analysis of the 1,112 cases of death? Q5 What is the problem with the government's diagnostic criteria and the solution? Q6 Who made what brands? Q7 Has there been a recall? What is still on sale? Q8 Was safety not checked by any producers? Q9 What are the government's responsibilities? Q10 Is it true that these products were sold only in Korea? Q11 Why and how was it unveiled only in 2011 after 17 years of sales? Q12 What delayed the resolution of the victim issue? Q13 What is the background of the prosecutor's investigation in early 2016? Q14 Is it possible to report new victim cases without evidence of product purchase? Q15 What is happening with the victim issue? Q16 How does it compare with the cases of Minamata disease and Wonjin Rayon? Q17 Are there prevention measures and lessons?

The Hospital Life of the Patient with Femoral Neck Fracture (대퇴경부 골절 환자의 입원 생활)

  • Kim, Kyung-Ja;Chi, Sung-Ai
    • Journal of Korean Academy of Nursing Administration
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    • v.2 no.1
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    • pp.35-56
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    • 1996
  • Nowerdays, the increase of traffic accidents and old age population make the Femoral Neck Fracture(FNF) patients increase. By the improvement of education and standard of living the patients demand better medical service than before. This study is designed to give practical help for the FNF patients by observing their hospital life and establish practical nursing strategies for the FNF patients. For these purposes the Ethnographic Participant Observation was adopted. By this study is focused on the hospital life patient's view. For this end, the field study adopted orthopedic ward in the C University Hospital with 400 beds in Seoul. The object patients of the study were twelve patients. The patients experienced five stages : Embarrassment, Conflict, Stability, Independent, and Extension Stage. The findings and prepared nursing strategies are stated as follows. First, in the Embarrassment Stage they suffered embarrassment, anxiety, pain, they could not do ordinary things. The patients who accidental fractures had anxiety from unfamiliar tests and from hospitalization itself. They lamented that they could not ordinary things, and do nothing but obeying the hospital, and endure the pain. They recognized the changed environment and resigned themselves to life in the ward. In this stage, full openness by the nurses is needed. Second, the attribute of the Conflict Stage were conflict, fear, curiosity, belief, reflection. When they sign the consentment form, they experience conflicts about the possibility of complication, fear of recovery from anesthesia, curiosity about the operation procedure, post - operation state, reflection on their past life, and promise to care for their family members after discharge and keep their religious life faithfully. And they accepted the operation depending on God, believing in modern medicine, and the surgeon. Asking for their changed informations, they expected positive results from the operation. In this stage, an empathic attitude by the nurses is needed. Third, the attribute of the Stability Stage were relief, gratitude, difficulty with excretion, and pain. When they awoke from anesthesia, they felt relief because of a the end of the operation, but they experienced extreme pain, difficulty of excretion in bed. They accepted the changed environment and expected recovery. In this stage, support by the nurses is needed. Fourth, the attributes of the Independence Stage were freedom, exercise, nurturing, anxiety, and discomfort. When they ambulated and exercised, they experienced freedom. They showed exhibited weakness of the digestive organs and discomfort hospital's space, structure, and facilities, the delay of medical certificate issue the lack of prompt response by the medical agents. They ate nurturious food and felt anxiety on the end of hospital life and returning to their ordinary life. They showed the independence of overcoming their environment by increasing exercise and expected their discharges. In this stage, respect by the nurses is needed for the patients to, overcome their environment and prepare for their independence. Fifth, the attributes of the Extension Stage were pessimism, isolation, dissatisfaction, and pain. Accompanied injury and old age made their ward life extend to over seven weeks. They exhibited weariness, melancholy, skeptisis, general pessimistic feeling, and desperation caused by their isolated life. They experienced the digestive discomfort caused by the prolonged medication and psycological pain caused by long-time hospitalization. As a, result, their dissatisfaction on the human, physical, and systematic environments had been increased. They acquired critical power and sought for something to do spending their time. They expected vaguely about the returning of their ordinary life. In this stage, counseling is needed by the nurse to overcome positively their psychological, social, and physical problems. The process of the FNF patient's ward life starts from the dependent state, when they are hospitalized, and gradually progresses to self-fulfillment in order to keep independent life. As a result, the FNF patients showed "Response in Challenge" or "Adaptation in Conflict" through their experiences of social, physical, and psychological difficulties.

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Fruiting body development and genetic analysis of somatic hybrids by protoplast fusion in edible fungi (식용버섯의 원형질체 융합체의 자실체 발생 및 유전분석)

  • Yoo, Young Bok;Kong, Won Sik;Oh, Se Jong;Jhune, Chang Sung;Shin, Pyung Gyun;Kim, Beom Gi;Kim, Gyu Hyun;Park, Minsun;Min, Byung Re
    • Journal of Mushroom
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    • v.2 no.3
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    • pp.115-126
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    • 2004
  • Somatic hybrids of inter-compatible and inter-incompatible strains were obtained by protoplast fusion. The fusion products between compatible strains, Pleurotus ostreatus and P. florida, formed heterokaryons, while fusants between incompatible strains such as P. cornucopiae + P. florida, P. ostreatus + Ganoderma applanatum, P. florida + Ganoderma lucidum, and P. ostreatus + Flammulina velutipes formed synkaryons that retained genes from both parents. The heterokaryons showed the same level of basidioma development. In contrast, the synkaryons showed unique characteristics including clamp connection formation at mitosis, either partner basidioma development, and abnormal segregation and recombination compared with inter-compatible strains. Synkaryons can be classified into homokaryoyic and heterokaryotic type. A comparison of somatic hybrids with compatible and incompatible strains was made using random amplified polymorphic DNA (RAPD) analysis. The heterokaryons between compatible species showed the same level of variability and contained both parental RAPD bands. In contrast, most of the synkaryons between incompatible species showed similarity to those of either parental bands and non-parental RAPD bands. Synkaryons can be classified into microgenome insertion type and macrogenome insertion type. A tetrapolar mating system was found among monospore isolates in somatic hybrids and wild type P. ostreatus. Homokaryons from each somatic hybrid combination were paired with tester homokaryons of the initial wild type of P. ostreatus. The changed mating types were identified in progenies. The pattern of mating type switching in somatic hybrids depends on compatibility of fusion partner. There are several factors related to the mechanism of clamp connection formation and fruiting body development of synkaryons. Of these,the major factor may be associated with self-fertility and mating type switching such as homokaryotic fruiting of wild type P. ostreatus. This review will discuss these aspects.

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Quantitative Analysis of Sesamin and Sesamolin in Various Cultivars of Sesame (참깨 품종별 Sesamin, Sesamolin 함량 변이)

  • Kim Geum-Soog;Kim Dong-Hwi;Jeong Mi-Ran;Jang In-Bok;Shim Kang-Bo;Kang Chul-Hwan;Lee Seung-Eun;Seong Nak-Sul;Song Kyung-Sik
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.6
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    • pp.496-502
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    • 2004
  • The development of sesame varieties which contain high contents of lignan compounds has been progressed in Korea. This study was carried out to get the basic information for the breeding of high quality sesame varieties and the development of health functional food sources using lignan compounds from sesame. The contents of sesamin and sesamolin were $4.08\pm1.74$ and $2.47\pm0.68mg/g$, respectively, from sesame cultivated in 2002 and those were $4.08\pm1.51$ and $2.48\pm0.69mg/g$, respectively, from sesame cultivated in 2003. The content of sesamine was high in the order of Danbaek (6.22 mg/g), Seongbun (5.94 mg/g), Namda (5.83 mg/g), and Naman (5.59 mg/g) producted in 2002 and Seongbun (6.27 mg/g), Dasak (5.53 mg/g), Danbaek (5.50 mg/g), chinbaek (5.45 mg/g), and Seodun (5.41 mg/g) producted in 2003. The content of sesmoline was high in the order of Hwangbaek (3.27 mg/g), Seongbun (3.26 mg/g), Annam (3.22 mg/g), Hanseom (3.17 mg/g), and Danbaek (3.16 mg/g) producted in 2002, and Seongbun (3.21 mg/g), Seodun (3.14 mg/g), Pungan (3.10 mg/g), Naman (3.09 mg/g), and Danbaek (3.04 mg/g) producted in 2003. The contents of sesamin and sesamolin of Yangbaek, which has used as a standard variety for sesame breeding, were relatively lower than in any other varieties. These resluts suggest that Yangbaek is not the proper variety as a standard variety for development of high quality sesame. In conclusion, proper good variety as a standard variety for sesame breeding must be determined after careful consideration on the major quality factors including crude oil and lignan compounds as well as agricultural characteristics to develop high quality sesame varieties containing high contents of lignan compounds.

A Preliminary Study for the Application of Michigan Alcoholism Screening Test-Geriatric Version in Korea (한국에서 노인용 미시간주정의존선별검사의 적용을 위한 예비연구)

  • Cheon, Jin-Sook;Oh, Byoung-Hoon;Choi, Young-Tai
    • Korean Journal of Biological Psychiatry
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    • v.6 no.1
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    • pp.102-110
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    • 1999
  • Objectives : The alcohol dependence in elderly people has been prevalent because of increase in geriatric population. However, it is difficult to find out alcohol dependence in the aged, because they have less specific clinical features as compared with adult alcoholics. The aims of this study were to screen alcohol dependence among elderly Koreans and to know the clinical characteristics of Korean delerly alcoholics. Methods : The questionnaires translated into Korean such as Michigan Alcoholism Screening Test(MAST-K), the Brief MAST and the MAST-Geriatirc Version (MAST-KG) were used to screen alcohol dependence in the elderly alcoholic inpatients aged over 60(N=43), adult alcoholic inpatients within 20-59 Yrs of age(N=60), which were compared with age matched normal healthy aged(N=18) or adult controls(N=45). The demographic data such as sex, age, education, occupation, socioeconomic status, marital status, numbers of children, dwelling and religion as well as alcohol history such as duration of alcohol drinking, onset age, family history, impulsivity, somatic illness and motivation were also obtained to identify characteristic features of Korean aged alcoholics by structured interviews. Results : 1) The aged alcoholics had the charateristic features of more in males, lower age, low education levels, more in blue-collar workers, lower socioeconomic class, more in single, few babies, more living alone, having no religion without statistical significance. 2) The onset age of alcohol dependence was significantly higher in the aged alcoholics($45.3{\pm}13.6Yrs$) than in the adult alcoholics($27.7{\pm}8.7Yrs$)(p<0.0001). The duration of problematic alcohol drinking was significantly longer in the aged alcoholics($22.0{\pm}15.1Yrs$) than in adult alcoholics($14.2{\pm}8.4Yrs$)(p<0.01). Otherwise, there were no significant difference between aged and adult alcoholics in the family history, imulsivity, somatic illness and motivation. 3) The mean score of the MAST-K was significantly higher in the aged alcoholics($20.6{\pm}5.4$) than in the normal aged($6.7{\pm}4.4$)(p<0.0001), which was significantly lower than in the adult alcoholics($26.2{\pm}8.0$) and in normal adult controls($9.5{\pm}3.2$)(p<0.05). The mean score of the Brief MAST was significantly lower in the aged alcoholics($9.3{\pm}3.5$) than in the adult alcoholics($14.5{\pm}6.6$)(p<0.0001). The mean score of the MAST-KG was significantly higher in the aged alcoholics($10.6{\pm}3.5$) than in the normal aged($4.8{\pm}4.3$)(p<0.0001). The former was significantly lower than in the adult alcoholics($12.9{\pm}4.3$)(p<0.005), and the mean score was $4.5{\pm}2.8$ in normal adult controls. 4) The items which showed statistically significant differences between aged alcoholics and normal aged controls could be found in 10 items of the MAST-K(items 2, 3, 4, 5, 11, 14, 17, 21, 22 and 23), 2 items of the Brief MAST(items 2 and 9), and 7 items of the MAST-KG(items 6, 13, 18, 19, 22, 23 and 24)(p<0.01). Conclusions : The scores of the MAST-K, the Brief MAST and the MAST-KG were significantly lower in the aged alcoholics than those in the adult alcoholics (p<0.05). The statistically significant differences between aged alcoholics and normal aged controls could be found in 10 items of the MAST-K, 2 items of the Brief MAST and 7 items of the MAST-KG. Therefore, a briefer rating scales around 10 items are needed to screen alcohol dependence among Korean elderly people.

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Analysis of Image Distortion on Magnetic Resonance Diffusion Weighted Imaging

  • Cho, Ah Rang;Lee, Hae Kag;Yoo, Heung Joon;Park, Cheol-Soo
    • Journal of Magnetics
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    • v.20 no.4
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    • pp.381-386
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    • 2015
  • The purpose of this study is to improve diagnostic efficiency of clinical study by setting up guidelines for more precise examination with a comparative analysis of signal intensity and image distortion depending on the location of X axial of object when performing magnetic resonance diffusion weighted imaging (MR DWI) examination. We arranged the self-produced phantom with a 45 mm of interval from the core of 44 regent bottles that have a 16 mm of external diameter and 55 mm of height, and were placed in 4 rows and 11 columns in an acrylic box. We also filled up water and margarine to portrait the fat. We used 3T Skyra and 18 Channel Body array coil. We also obtained the coronal image with the direction of RL (right to left) by using scan slice thinkness 3 mm, slice gap: 0mm, field of view (FOV): $450{\times}450mm^2$, repetition time (TR): 5000 ms, echo time (TE): 73/118 ms, Matrix: $126{\times}126$, slice number: 15, scan time: 9 min 45sec, number of excitations (NEX): 3, phase encoding as a diffusion-weighted imaging parameter. In order to scan, we set b-value to $0s/mm^2$, $400s/mm^2$, and $1,400s/mm^2$, and obtained T2 fat saturation image. Then we did a comparative analysis on the differences between image distortion and signal intensity depending on the location of X axial based on iso-center of patient's table. We used "Image J" as a comparative analysis programme, and used SPSS v18.0 as a statistic programme. There was not much difference between image distortion and signal intensity on fat and water from T2 fat saturation image. But, the average value depends on the location of X axial was statistically significant (p < 0.05). From DWI image, when b-value was 0 and 400, there was no significant difference up to $2^{nd}$ columns right to left from the core of patient's table, however, there was a decline in signal intensity and image distortion from the $3^{rd}$ columns and they started to decrease rapidly at the $4^{th}$ columns. When b-value was 1,400, there was not much difference between the $1^{st}$ row right to left from the core of patient's table, however, image distortion started to appear from the $2^{nd}$ columns with no change in signal intensity, the signal was getting decreased from the $3^{rd}$ columns, and both signal intensity and image distortion started to get decreased rapidly. At this moment, the reagent bottles from outside out of 11 reagent bottles were not verified from the image, and only 9 reagent bottles were verified. However, it was not possible to verify anything from the $5^{th}$ columns. But, the average value depends on the location of X axial was statistically significant. On T2 FS image, there was a significant decline in image distortion and signal intensity over 180mm from the core of patient's table. On diffusion-weighted image, there was a significant decline in image distortion and signal intensity over 90 mm, and they became unverifiable over 180 mm. Therefore, we should make an image that has a diagnostic value from examinations that are hard to locate patient's position.

Observations of Oxygen Administration Effects on Visuospatial Cognitive Performance using Time Course Data Analysis of fMRI (뇌기능 자기공명영상의 시계열 신호 분석에 의한 공간인지과제 수행시 산소 공급의 효과 관찰)

  • Sohn Jin-Hun;You Ji-Hye;Eom Jin-Sup;Lee Soo-Yeol;Chung Soon-Cheol
    • Investigative Magnetic Resonance Imaging
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    • v.9 no.1
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    • pp.9-15
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    • 2005
  • Purpose : This study attempted to investigate the effects of supply of highly concentrated $(30\%)$ oxygen on human ability of visuospatial cognition using time course data analysis of functional Magnetic Resonance Imaging (fMRI). Materials and Methods : To select an item set in the visuospatial performance test, two questionnaires with similar difficulty were developed through group testing. A group test was administered to 263 college students. Two types of questionnaire containing 20 questions were developed to measure the ability of visuospatial cognition. Eight college students (right-handed male, average age of 23.5 yrs) were examined for fMRI study. The experiment consisted of two runs of the visuospatial cognition testing, one with $21\%$ level of oxygen and the other with $30\%$ oxygen level. Each run consisted of 4 blocks, each containing control and visuospatial items. Functional brain images were taken from 37 MRI using the single-shot EPI method. Using the subtraction procedure, activated areas in the brain during visuospatial tasks were color-coded by t-score. To investigate the time course data in each activated area from brain images, 4 typical regions (cerebellum, occipital lobe, parietal lobe, and frontal lobe) were selected. Results : The average accuracy was $50.63{\pm}8.63$ and $62.50{\pm}9.64$ for $21\%\;and\;30\%$ oxygen respectively, and a statistically significant difference was found in the accuracy between the two types of oxygen (p<0.05). There were more activation areas observed at the cerebellum, occipital lobe, parietal lobe and frontal lobe with $30\%$ oxygen administration. The rate of increase in the cerebellum, occipital lobe and parietal lobe was $17\%$ and that of the frontal lobe, $50\%$. Especially, there were increase of intensity of BOLD signal at the parietal lobe with $30\%$ oxygen administration. The increase rate of the left parietal lobe was $1.4\%$ and that of the right parietal lobe, $1.7\%$. Conclusion : It is concluded that while performing visuospatial tasks, high concentrations of oxygen administration make oxygen administration sufficient, thus making neural network activate more, and the ability to perform visuospatial tasks increase.

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Isolation and Identification of a Photosensitizer from Pueraria thunbergiana Leaves that Induces Apoptosis in SK-HEP-1 Cells (P. thunbergiana 잎으로부터 SK-HEP-1세포에 대한 apoptosis를 유도하는 광과민성물질의 분리 및 구조동정)

  • Lee, Jun Young;Kim, Mi Kyeong;Ha, Jun Young;Kim, Yong Gyun;Hong, Chang Oh;Kim, So Young;Kim, Chung-Hwan;Kim, Keun Ki
    • Journal of Life Science
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    • v.24 no.3
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    • pp.242-251
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    • 2014
  • The objective of this study was to isolate a photosensitizer from Pueraria thunbergiana leaves that induces apoptosis in SK-HEP-1 cells. Column chromatography and thin layer chromatography were used to isolate active compounds from extracts of P. thunbergiana leaves. The structures of the isolated compounds were determined by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. A substance, named M4-3, was purified from the leaves of P. thunbergiana using various chromatography methods, and the absorbance of the substance was measured. The absorbance was highest at 410 nm, suggesting that the M4-3 substance was a different compound from chlorophyll a and b, which absorb at 410, 502, 533, and 607 nm. Further analyses revealed that the M4-3 compound was a $13^2$-hydoxy pheophorbide, a methyl ester with a molecular weight of 662. M4-3 was identified as a derivative compound of pheophorbide, with a structure that magnesium comes away from the porphyrin ring. The results of the analysis of the cytotoxicity of the M4-3 substance against the SK-HEP-1 cells revealed that it inhibited rates of cell growth by 40% and 80% at a concentration of 0.04 ${\mu}M$ and 0.08 ${\mu}M$, respectively. The M4-3 compound was found to be a photosensitizer for cytotoxicity because it was appeared only in light condition as examining activity in different irradiation conditions (light condition and nonlight condition) under the same concentration. Analysis of morphological changes in the cells following cell death induced by exposure to the M4-3 substance reveled representative phenomena of apoptosis (nuclear condensation, vesicle formation, and fragmentation of DNA). The induction of apoptosis was attributed to the compound's photodynamic activity.