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Surgical Treatment of the Congenital Esophageal Atresia (선천성 식도 폐쇄증의 외과적 치료)

  • 최필조;전희재;이용훈;조광조;성시찬;우종수
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.567-572
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    • 1999
  • Background: Surgical correction of the full spectrum of esophageal atresia with tracheoesophageal fistula has improved over the years, but the mortality and morbidity assoiated with repair of these anomalies still remains high. Material and Method: We retrospectively analyzes 27 surgically treated patients with esophageal atresia and tracheoesophageal fistula at Dong-A University Hospital between January 1992 and March 1997. Result: There were 21 male and 6 female patients. Mean birth weight was 2.62$\pm$.385 kg(2.0~3.4 kg). Twenty- four(88.9%) had esophageal atresia with distal tracheoesophageal fistula, and 3(11.1%) had pure esophageal atresia. Four(14.8%) infants were allocated to Waterston risk group A, 18(66.7%) to group B, and 5(18.5%) to group C. In eighteen(66.7%) infants with associated anomalies, cardiovascular anomalies were the most common. Three had a gap length of 3.5 cm or greater(ultra-long gap) between esophageal segments, 7 had 2.0 to 3.5 cm(long gap), 8 had 1.0 to 2.0 cm(medium gap), and 9 had 1 cm or less(short gap) gap length. Among 27 neonates, 3 cases underwent staged operation, late colon interposition was done in 2, and all other 24 cases underwent primary esophageal anastomosis. Oerative mortality was 2/27(7.4%). Causes of death included acute renal failure(n=1), empyema from anastomotic leak(n=1), necrotizing enterocolitis(n=1), sepsis(n=1), insulin-dependent diabetus mellitus(n=1 . There were 4 anastomosis- related complications including stricture in 3, leakage in 1. Mortality was related to the gap length(p<.05). Conclusion: Although the complication rate associated with surgical repair of these anomalies is high, this does not always implicate the operative mortality. The overall survival can be improved by effective treatment for combined anomalies and intensive postoperatve care.

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Structural Identification of Antibiotics from Pseudomonas sp. RRj 228, a Antifungal Activity of Collectotrichum acutatum Causing Anthracnose on Pepper (Pseudomonas sp. RRj 228이 분비하는 항균물질의 동정과 고추탄저균 C. acutatum에 대한 항균활성)

  • Jeon, Sang-Yoon;Kim, Yong-Gyun;Lee, Sang-Mong;Son, Hong-Joo;Park, Hyean-Cheal;Kim, Sun-Tae;Park, Ki-Do;Kang, Ui-Gum;Kim, Keun-Ki
    • Journal of Life Science
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    • v.20 no.8
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    • pp.1254-1260
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    • 2010
  • Microorganisms near the plant rhizosphere usually inhabit the surface or the inside of the plant roots and have a direct effect on plant growth by secreting plant growth promoters or antagonistic materials which protect the root zone system from various pathogens. This study was carried out to identify and isolate the antagonistic materials after isolation of microorganisms showing high antagonistic activities, in hopes of contributing to the development of sustainable agriculture and the preservation of agricultural environments. A number of antagonistic bacteria were isolated from paddy soil. Among isolates, RRj 228 showed plant growth promotion and antagonistic activity. RRj 228 was identified as Pseudomonas sp. according to the results of physiological properties and genetic methods. On the basis of the results of anti-fungal spectrum against several pathogens by RRj 228, the antagonistic effect of the isolate against Botrytis cinerea, Pythium ultimum, Phytopthola capsici, and Rhizoctonia solani, especially against red-pepper anthracnose caused by Colletotrichum acutatum, was remarkable. The experiment evaluating the biological control effect by RRj 228 revealed that the $ED_{50}$ value by the RRj 228 culture against C. acutatum, R. solani and P. ultimum were 0.14 mg/ml, 0.16 mg/ml and 0.29 mg/ml, respectively. An antagonistic substance was isolated and purified by several chromatographies from the RRj 228 culture. The $^1H$ and $^{13}C$ assignment of the antagonistic substance was achieved from two-dimensional $^1H-^1H$ COSY, HMQC, and HMBC. Finally, the antagonistic substance was identified as Phenazine-1-carboxylic acid ($C_{13}H_8N_2O_2$, M.W.=224).

Excimer-Based White Phosphorescent OLEDs with High Efficiency

  • Yang, Xiaohui;Wang, Zixing;Madakuni, Sijesh;Li, Jian;Jabbour, Ghassan E.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1520-1521
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    • 2008
  • There are several ways to demonstrate white organic light emitting diodes (OLEDs) for displays and solid state lighting applications. Among these approaches are the stacked three primary or two complementary colors light-emitting layers, multiple-doped emissive layer, and excimer and exciplex emission [1-10]. We report on white phosphorescent excimer devices by using two light emitting materials based on platinum complexes. These devices showed a peak EQE of 15.7%, with an EQE of 14.5% (17 lm/W) at $500\;cd/m^2$, and a noticeable improvement in both the CIE coordinates (0.381, 0.401) and CRI (81). Devices with the structure ITO/PEDOT:PSS/TCTA (30 nm)/26 mCPy: 12% FPt (10 nm) /26 mCPy: 2% Pt-4 (15 nm)/BCP (40 nm)/CsF/Al [device 1], ITO/PEDOT:PSS/TCTA (30 nm)/26 mCPy: 2% Pt-4 (15 nm)/26 mCPy: 12% FPt (10 nm)/BCP (40 nm)/CsF/Al [device 2], and ITO/PEDOT:PSS/TCTA (30 nm)/26 mCPy: 2% Pt-4: 12% FPt (25 nm)/BCP (40 nm)/CsF/Al [device 3] were fabricated. In these cases, the emissive layer was either the double-layer of 26 mCPy:12% FPt and 15 nm 26 mCPy: 2% Pt-4, or the single layer of 26mCPy with simultaneous doping of Pt-4 and FPt. Device characterization indicates that the CIE coordinates/CRI of device 2 were (0.341, 0.394)/75, (0.295, 0.365)/70 at 5 V and 7 V, respectively. Significant change in EL spectra with the drive voltage was observed for device 2 indicating a shift in the carrier recombination zone, while relatively stable EL spectra was observed for device 1. This indicates a better charge trapping in Pt-4 doped layers [10]. On the other hand, device 3 having a single light-emitting layer (doped simultaneously) emitted a board spectrum combining emission from the Pt-4 monomer and FPt excimer. Moreover, excellent color stability independent of the drive voltage was observed in this case. The CIE coordinates/CRI at 4 V ($40\;cd/m^2$) and 7 V ($7100\;cd/m^2$) were (0.441, 0.421)/83 and (0.440, 0.427)/81, respectively. A balance in the EL spectra can be further obtained by lowering the doping ratio of FPt. In this regard, devices with FPt concentration of 8% (denoted as device 4) were fabricated and characterized. A shift in the CIE coordinates of device 4 from (0.441, 0.421) to (0.382, 0.401) was observed due to an increase in the emission intensity ratio of Pt-4 monomer to FPt excimer. It is worth noting that the CRI values remained above 80 for such device structure. Moreover, a noticeable stability in the EL spectra with respect to changing bias voltage was measured indicating a uniform region for exciton formation. A summary of device characteristics for all cases discussed above is shown in table 1. The forward light output in each case is approximately $500\;cd/m^2$. Other parameters listed are driving voltage (Bias), current density (J), external quantum efficiency (EQE), power efficiency (P.E.), luminous efficiency (cd/A), and CIE coordinates. To conclude, a highly efficient white phosphorescent excimer-based OLEDs made with two light-emitting platinum complexes and having a simple structure showed improved EL characteristics and color properties. The EQE of these devices at $500\;cd/m^2$ is 14.5% with a corresponding power efficiency of 17 lm/W, CIE coordinates of (0.382, 0.401), and CRI of 81.

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Method for Validation of Caffeoylquinic Acid Derivatives in Ligularia fischeri Leaf Extract as Functional Ingredients (건강기능식품 기능성 원료로서 곰취잎 추출물의 Caffeoylquinic Acid계 성분 분석법 검증)

  • Kwon, Jin Gwan;Kim, Jin Kyu;Seo, Changon;Hong, Seong Su;Ahn, Eun-Kyung;Seo, Dong-Wan;Oh, Joa Sub
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.1
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    • pp.61-67
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    • 2016
  • An HPLC analysis method was developed for standard determinations of chlorogenic acid, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid as functional health materials in Ligularia fischeri extract. HPLC was performed on a $C_{18}$ Kromasil column ($4.6{\times}250mm$, $5{\mu}m$ column) with a gradient elution of 0.1% (v/v) trifluoroacetic acid and acetonitrile at a flow rate of 1.0 mL/min at $30^{\circ}C$. The analytes were detected at 330 nm. The HPLC method was validated in accordance with the International Conference on Harmonization guideline of analytical procedures with respect to specificity, precision, accuracy, and linearity. The limits of detection and quantitation for the four compounds were 3.0~14.6 and $9.2{\sim}44.4{\mu}g/mL$, respectively. Calibration curves showed good linearity ($r^2$ > 0.999), and the precision of analysis was satisfied (less than 0.9%). Recoveries of quantified compounds ranged from 98.96 to 101.81%. This result indicates that the established HPLC method is very useful for the determination of marker compounds in Ligularia fischeri leaf extracts.

THE CHARACTERISTICS OF CHILD AND ADOLESCENT INPATIENTS WITH SEVERE OBSESSIVE-COMPULSIVE DISORDER (심각한 소아 ${\cdot}$ 청소년 강박장애로 입원한 환아들의 특징)

  • Hwang, Jun-Won;You, So-Young;Chang, Jun-Hwan;Shin, Min-Sup;Cho, Soo-Churl;Hong, Kang-E;Kim, Boong-Nyun
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.15 no.2
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    • pp.143-151
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    • 2004
  • Objectives : Child and adolescent onset obsessive compulsive disorder(C-OCD) is known to be associated with poor drug response, high comorbid rate and strong genetic tendencies. Till now studies for C-OCD have been very rare in Korea. We conducted this study to investigate the informations about clinical features, familial psychiatric loading, treatment profiles and course of server C-OCD from the retrospective analysis of inpatient data of Seoul National University Children's Hospital. Method : Retrospective chart review and data analysis was performed. Twenty(male 16 : female 4) patients with final C-OCD diagnosis by DSM-IV at discharge from 1994 to 2002 were found and their medical chart, psychological data, family interview data and nursing reports were collected and analyzed. Results : 1) The sex ratio of C-OCD was male dominant(4:1). 2) Phenomenological, most common obsession was pathologic doubt, contamination fear, followed by aggressive obsession, need for symmetry, sexual obsession, most common compulsion was checking and washing, followed by breathing, movement, symmetry, repetitive asking, hoarding, mental compulsion. 3) Most common comorbid diagnosis was depression. Other axis-I diagnosis associated OCD were anxiety disorder, tic disorder, conduct and oppositional defiant disorder and psychosis. 4) Regarding psychiatric familial loadings, 17 patients(85%) had relatives with psychiatric disorders, OC-spectrum disorders(OCD or OCPD) were found in 9 patients(45%). 5) The majority of patients(75%) have received SSRI and antipsychotics treatment. The response rate above 'moderate improved" by CGI was 75%. 6) During follow-up period in outpatient clinic, five patients(25%) showed continuous complete remission, 10 patients (50%) did residual symptoms with chronic course. Conclusion : This seems to be the first systemic investigation of severe pediatric OCD patients in Korea. The children & adolescents with severe OCD in inpatient-setting showed the high comorbid rate, familial psychiatric loading, and combined pharmacotherapy with antipsychotics, As for symptoms, high rate of aggressive-sexual obsession and atypical compulsions like breathing and moving was reported in this study. Severe pediatric OCD patients, however, responded well to the combined SSRI and antipsychotics regimen.

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Oxide perovskite crystals type ABCO4:application and growth

  • Pajaczkowska, A.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.258-292
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    • 1996
  • In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

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Analysis of the Geological Structure of the Hwasan Caldera Using Potential Data (포텐셜 자료해석을 통한 화산칼데라 구조 해석)

  • Park, Gye-Soon;Yoo, Hee-Young;Yang, Jun-Mo;Lee, Heui-Soon;Kwon, Byung-Doo;Eom, Joo-Young;Kim, Dong-O;Park, Chan-Hong
    • Journal of the Korean earth science society
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    • v.29 no.1
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    • pp.1-12
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    • 2008
  • A geophysical mapping was performed for Hwasan caldera which is located in Euisung Sub-basin of the southeastern part of the Korean Peninsula. In order to overcome the limitation of the previous studies, remote sensing technic was used and dense potential data were obtained and analyzed. First, we analyzed geological lineament for target area using geological map, digital elevation model (DEM) data and satellite imagery. The results were greatly consistent with the previous studies, and showed that N-S and NW-SE direction are the most dominant one in target area. Second, based on the lineament analysis, highly dense gravity data were acquired in Euisung Sub-basin and an integrated interpretation considering air-born magnetic data was made to investigate the regional structure of the target area. The results of power spectrum analysis for the acquired potential data revealed that the subsurface of Euisung Sub-basin have two density discontinuities at about 1 km and 3-5 km depth. A 1 km depth discontinuity is thought as the depth of pyroclastic sedimentary rocks or igneous rocks which were intruded at the ring vent of Hwasan caldera, while a 3-5 km depth discontinuity seems to be associated with the depth of the basin basement. In addition, three-dimensional gravity inversion for the total area of Euisung Sub-basin was carried out, and the inversion results indicated two followings; 1) Cretaceous Palgongsan granite and Bulguksa intrusion rocks, which are located in southeastern part and northeastern part of Euisung Sub-basin, show two major low density anomalies, 2) pyroclastic rocks around Hwasan caldera also have lower density when compared with those of neighborhood regions and are extended to 1.5 km depth. However, a poor vertical resolution of potential survey makes it difficult to accurately delineate the detailed structure caldera which has a vertically developed characteristic in general. To overcome this limitation, integrated analysis was carried out using the magnetotelluric data on the corresponding area with potential data and we could obtain more reasonable geologic structure.

Automatic Detection of Stage 1 Sleep Utilizing Simultaneous Analyses of EEG Spectrum and Slow Eye Movement (느린 안구 운동(SEM)과 뇌파의 스펙트럼 동시 분석을 이용한 1단계 수면탐지)

  • Shin, Hong-Beom;Han, Jong-Hee;Jeong, Do-Un;Park, Kwang-Suk
    • Sleep Medicine and Psychophysiology
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    • v.10 no.1
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    • pp.52-60
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    • 2003
  • Objectives: Stage 1 sleep provides important information regarding interpretation of nocturnal polysomnography, particularly sleep onset. It is a short transition period from wakeful consciousness to sleep. The lack of prominent sleep events characterizing stage 1 sleep is a major obstacle in automatic sleep stage scoring. In this study, utilization of simultaneous EEG and EOG processing and analyses to detect stage 1 sleep automatically were attempted. Methods: Relative powers of the alpha waves and the theta waves were calculated from spectral estimation. A relative power of alpha waves less than 50% or relative power of theta waves more than 23% was regarded as stage 1 sleep. SEM(slow eye movement) was defined as the duration of both-eye movement ranging from 1.5 to 4 seconds, and was also regarded as stage 1 sleep. If one of these three criteria was met, the epoch was regarded as stage 1 sleep. Results were compared to the manual rating results done by two polysomnography experts. Results: A total of 169 epochs were analyzed. The agreement rate for stage 1 sleep between automatic detection and manual scoring was 79.3% and Cohen’s Kappa was 0.586 (p<0.01). A significant portion (32%) of automatically detected stage 1 sleep included SEM. Conclusion: Generally, digitally-scored sleep staging shows accuracy up to 70%. Considering potential difficulty in stage 1 sleep scoring, accuracy of 79.3% in this study seems to be strong enough. Simultaneous analysis of EOG differentiates this study from previous ones which mainly depended on EEG analysis. The issue of close relationship between SEM and stage 1 sleep raised by Kinnari remains a valid one in this study.

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Changes in Allergenicity and Quality of Nuruk during Fermentation (전통 누룩 발효과정 중 품질 및 항원성 변화)

  • Lee, Hyo-Hyung;Lee, Jin-Hyeong;Ko, Yu-Jin;Park, Mi-Hwa;Lee, Jeong-Ok;Ryu, Chung-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.1
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    • pp.76-82
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    • 2009
  • Wheat is the most widely cultivated cereal and an important source of dietary protein worldwide. Wheat allergy, defined as an adverse immunologic reaction to wheat, encompasses a broad spectrum of disorders with different pathomechanisms and clinical manifestation. The Nuruk, a traditional Korean Koji for brewing, was made with wheat flour and fermenting microbes such as bacteria, yeast and mold. The strains grown on Nuruk secrete various enzymes as amylase and protease. By the activation of such enzymes, starch and proteins in Nuruk are hydrolyzed to sugar and amino acid. Therefore, it is supposed to reduce allergic proteins in wheat. To study quality properties and degradation degree of allergenicity in Nuruk by fermentation, we investigated the changes of general ingredients and allergenicity in Nuruk during fermentation. Moisture contents was decreased from 24.2% to 13.6% during fermentation. Crude lipid and protein contents were gradually increased during fermentation. After 15 days of fermentation, reducing sugar and total sugar contents were reached its maximum level, and they were 27.45% and 39.00%, respectively. Acid and neutral protease activity were significantly increased during fermentation, but alkaline protease activity was not detected. ${\alpha}$-amylase activity was gradually increased and showed maximum level about 2,833.00 U/g after 15 days of fermentation. Glucoamylase activity was the highest level about 497.9 U/g after 10 days of fermentation. The increase of these proteolytic and saccharogenic enzyme activities will provide efficient condition for production of rice wine. Also, protein fractions were isolated from Nuruk, and degradation of these proteins during fermentation were confirmed by SDS-PAGE. IgE immunoblotting using patient's sera with wheat allergy was performed to confirm allergenic protein in Nuruk. These results as fermentation of Nuruk will provide a useful tool for developing safer wheat products to prevent wheat allergy.

Cervical Tuberculous Lymphadenitis : Clinicopathological Features and AFB Positivity (결핵성 경부 림프절염의 병리소견과 항산균 검출 및 임상소견에 관한연구)

  • Hwang, Young-Jun;Ko, Mi-Hye;Yun, Se-Young;Kim, Yong-Ho;Kim, Doh-Hyung;Lee, Kye-Young;Kim, Keun-Youl;Myong, Na-Hye;Park, Jae-Seuk
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.5
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    • pp.720-729
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    • 2000
  • Background : Histological analysis of tuberculosis shows a spectrum of findings, from well formed granulomatous inflammation with few bacilli in patient with normal immune response to M. tuberculosis to poorly formed granulomatous inflammation with many bacilli in patient with defective immune response. To evaluate the degree of immune response to M. tuberculosis, we studied the histologic features, including the presence of acid fast bacilli(AFB) in lymph node of patients with cervical tuberculous lymphadenitis, and compared them with clinical characteristics. Methods : We reviewed the histologic features of 33 cases of cervical tuberculous lymphadenitis and processed the excised nodes for auramine-rhodamine staining to detect AFB. The AFB positivity in tissue was compared with the histologic features(degree of granuloma formation, presence of caseation necrosis, presence of neutrophilic infiltration) and clinical characteristics(lymph node size, duration of symptom, presence of local symptom or radiologic evidence of pulmonary tuberculosis). Results : 1) The mean age at diagnosis was 42.4 years, and male to female ratio was 1:4.5. 2) Histologically, all cases showed well formed granuloma and variable degrees of caseation necrosis, and 39% of the cases showed neutrophilic infiltration in the granulomatous inflammation. 3) AFB were confirmed in 52% of the cases, and they were found extracellularly and at the periphery of caseation necrosis. 4) There was no association between AFB positivity and histological features or clinical characteristics. Conclusion : Cervical tuberculous lymphadenitis showed well formed granulomatous inflammation with caseation necrosis, and there was no association between AFB positivity in the tissue and histological or clinical characteristics.

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