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Antibacterial Activity of Ceftizoxime Against Gram Negative Enteric Bacteria in vitro and in vivo (Ceftizoxime의 장내세균에 대한 시험관내 및 생체내 항균효과)

  • Byun, Woo-Mok;Chang, Jae-Chun;Park, Bok-Hwan;Kim, Hee-Sun;Kim, Sung-Kwang
    • Journal of Yeungnam Medical Science
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    • v.6 no.1
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    • pp.59-68
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    • 1989
  • Ceftizoxime sodium is a new synthetic ${\beta}$-lactam antibiotic combining potent antibacterial activity with high stability to a wide range of bacterial ${\beta}$-lactamase. This experiment was achieved to evaluate the antibacterial activities of ceftizoxime sodium againist Gram negative enteric bacteria isolated from in outpatient visiting Yeungnam university hospital and to study the emergence of drug induced bacterial varients which resist to ceftizoxime in vitro. The antibacterial activity of the ceftizoxime was compared with that of antibiotics and its effect on population of normal intestinal flora in mice was observed. The results are summarized as follows : 1. Highly effective antibacterial activity of ceftizoxime against Gram negative enteric bacilli was demonstrated and this antibacterial activity was superior to that of ampicillin. 2. Several test strains shows multiple antibiotic resistence. Among 15 strains of Escherichia coli, 1 strain was resistent to ampicillin, cefadroxyl, gentamicin, tetracycline, and 2 strains were resistent to ampicillin, cefadroxyl, tetracycline, five strains of Escherichia coli and Enterobacter cloacae was resistent to amplicillin, tetracycline and Shigella dysenteria was resistent to ampicillin, gentamicin, tetracycline. 3. The frequency of in vitro emergence of resistent varients among ceftizoxime sensitive bacteria in the presence of increasing concentrations of the compound was found to be low. 4. Plasmid was isolated in 6 of 9 strains (6 strains of Escherichia coli, Shigella dysenteriae, Enterobacter cloaceae and Salmonella typhi) That showed different antibiotic resistance. They were 5 strains of Escherichia coli and 1 strain of Shigella dysenteriae. However, plasmid could not be considered as a hallmark for antibiotic resistance by this. Further studies with curing experiment are to be accomplished for this purpose. 5. Changes in the bacterial count of normal intestinal flora following 25mg/kg/day administration of ceftizoxime over S consecutive days were not significant. In conclusion, ceftizoxime appeared to be a drug of choice in the treatment of Gram negative enteric bacilli infection.

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Biochemical Characterizations of Phenylalanine Ammonia-Lyase and its Mutants to Develop an Enzymatic Therapy for Phenylketonuria (페닐케톤뇨증의 효소치료 개발을 위한 phenylalanine ammonia-lyase 및 유전자 변이형의 생화학적 특성)

  • Kim, Woo-Mi
    • Journal of Life Science
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    • v.19 no.9
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    • pp.1226-1231
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    • 2009
  • Enzyme substitution with recombinant phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) is currently being explored for treatment of phenylketonuria (PKU), an autosomal recessive genetic disorder with mutations of the gene encoding phenylalanine-4-hydroxylase (EC 1.14.16.1). However, oral administration of PAL is limited because of proteolytic digestion in the gastrointestinal tract. The aim of this study was to determine the biochemical properties of PAL and delinate the susceptibility of wild-type PAL to pancreatic proteolysis by exploring several mutants, and to develop therapeutic drugs with PAL for PKU. The specific activity of PAL was assayed and its optimal pH, temperature stability, and intestinal protease susceptibility were investigated. Its $V_{max}$ values for phenylalanine and tyrosine were 1.77 and $0.47{\mu}mol$/ min/mg protein, respectively, and its $K_m$ values were $4.77{\times}10^{-4}$ and $4.37{\times}10^{-4}\;M$, respectively. PAL showed an optimal pH at 8.5, corresponding to the average pH range of the small intestine. It showed no loss of activity at $-80^{\circ}C$ for 5 months and possessed 93.4% of its activity under $4^{\circ}C$ for 4 wks. PAL was susceptible to chymotrypsin digestion and, to a lesser extent, to trypsin, elastase, carboxypeptidase A, and B. The trypsin and chymotrypsin cleaving sites were mutated to investigate protection from pancreatic digestion and the specific activities of these mutants were evaluated. The six mutants displayed low specific activities compared to the wild-type, suggesting that the primary trypsin and chymotrypsin cleaving sites may be essential for catalytic reaction. The PAL mutants could therefore be applied as a pretreatment modality without susceptibility to proteolytic attack, however, additional modification for enhancing enzymatic activity is needed to reduce the Phe levels effectively.

Effect of supercooling on the storage stability of rapidly frozen-thawed pork loins (과냉각 온도가 급속냉동-해동 처리된 돈육 등심의 저장성에 미치는 영향)

  • Choi, Eun Ji;Park, Hae Woong;Chung, Young Bae;Kim, Jin Se;Park, Seok Ho;Chun, Ho Hyun
    • Food Science and Preservation
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    • v.24 no.2
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    • pp.168-180
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    • 2017
  • This study was performed to determine the rapid thawing method for reducing the thawing time of frozen pork loins and to examine the effects of supercooling on the microbiological, physicochemical, and sensory qualities of fresh and frozen-thawed pork during storage at -1.5, 4, and $15^{\circ}C$. Forced-air thawing at $4^{\circ}C$ was the most time-consuming process, whereas radio frequency thawing time was the shortest by dielectric heating. The supercooling storage temperature was chosen to be $-1.5^{\circ}C$ because microstructural damages were not observed in the pork sample after cooling at $-1.5^{\circ}C$ for 24 h. Fresh or frozen-thawed pork loins stored at $-1.5^{\circ}C$ had lower drip loss and total volatile base nitrogen, thiobarbituric acid-reactive substance, and Hunter b* levels than loins stored at 4 and $15^{\circ}C$. In addition, the least degree of increase in preexisting microorganisms counts of the fresh or frozen-thawed pork loin samples was obtained during supercooled storage at $-1.5^{\circ}C$. Sensory quality results of fresh and frozen-thawed pork loin samples stored at $-1.5^{\circ}C$ showed higher scores than the samples stored at 4 and $15^{\circ}C$. These data indicate that supercooling at $-1.5^{\circ}C$ in the meat processing industry would be effective for maintaining the quality of pork meats without ice crystal nucleation and formation.

Early Failure of Cortical-Bone Screw Fixation in the Lumbar Spinal Stenosis (요추부 협착에서의 피질골 궤도 나사못 고정의 초기 실패 사례에 대한 고찰)

  • Kwon, Ji-Won;Kim, Jin-Gyu;Ha, Joong-Won;Moon, Seong-Hwan;Lee, Hwan-Mo;Park, Yung
    • Journal of the Korean Orthopaedic Association
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    • v.55 no.5
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    • pp.405-410
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    • 2020
  • Purpose: Pedicle screw insertion has been traditionally used as a surgical treatment for degenerative lumbar spine disease. As an alternative, the cortical-bone trajectory screw allows less invasive posterior lumbar fixation and excellent mechanical stability, as reported in several biomechanical studies. This study evaluated the clinical and radiological results of a case of early failure of cortical-bone screw fixation in posterior fixation and union after posterior decompression. Materials and Methods: This study examined 311 patients who underwent surgical treatment from 2013 to 2018 using cortical orbital screws as an alternative to traditional pedicle screw fixation for degenerative spinal stenosis and anterior spine dislocation of the lumbar spine. Early fixation failure after surgery was defined as fixation failure, such as loosening, pull-out, and breakage of the screw on computed tomography (CT) and radiographs at a follow-up of six months. Results: Early fixation failure occurred in 46 out of 311 cases (14.8%), screw loosening in 46 cases (14.8%), pull-out in 12 cases (3.9%), and breakage in four cases (1.3%). An analysis of the site where the fixation failure occurred revealed the following, L1 in seven cases (15.2%), L2 in three cases (6.5%), L3 in four cases (8.7%), L4 in four cases (8.7%), L5 in four cases (8.7%), and S1 in 24 cases (52.2%). Among the distal cortical bone screws, fixation failures such as loosening, pull-out, and breakage occurred mainly in the S1 screws. Conclusion: Cortical-bone trajectory screw fixation may be an alternative with comparable clinical outcomes or fewer complications compared to conventional pedicle screw fixation. On the other hand, in case with osteoporosis and no anterior support structure particularly at L5-S1 fusion sites were observed to have result of premature fixation failures such as relaxation, pull-out, and breakage.

Importance and requirements for dental prosthesis order platform services: a survey of dental professionals (치과 보철물 거래 플랫폼 서비스의 중요성과 요구사항: 치과 전문가 설문조사)

  • Gyu-Ri Kim;Keunbada Son;Du-Hyeong Lee;So-Yeun Kim;Myoung-Uk Jin;Kyu-Bok Lee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.39 no.3
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    • pp.105-118
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    • 2023
  • Purpose: This study aimed to gain better understanding of the importance of dental prosthesis order platform services and to identify the essential elements for their enhancement and wider adoption among dental professionals. Materials and Methods: A survey was conducted to assess the perspectives of dentists, dental technicians, dental hygienists, and dental industry professionals toward dental prosthesis ordering and associated platform services (a total of 53 respondents). The questionnaire was devised after an expert review and assessed for reliability using Cronbach's alpha coefficient. Factor analysis revealed that 57 factors across five categories accounted for 88.417% of the total variance. The survey was administered through an online questionnaire platform, and data analysis was conducted using a statistical software, employing one-way analysis of variance and Tukey's honestly significant difference test (α = 0.05). Results: The essential elements identified were accurate information input, effective communication, delivery of distortion-free impressions, convenience in data transmission and storage, development of stable and affordable platform services (P < 0.05). Furthermore, significant differences were observed in the importance of these items based on age, dental profession, and career experience (P < 0.05). Conclusion: The dental prosthesis ordering platform services, the requirements of dental personnel were stability, economic efficiency, and ease of transmitting and storing prosthesis data. The findings can serve as important indicators for the development and improvement of dental prosthesis order platform services.

The effects of career exploration programs using career portfolio and teacher-directed on the career maturity and career identity in middle school students (커리어포트폴리오형 및 교사주도형 진로탐색 프로그램이 중학생의 진로성숙도와 진로정체감에 미치는 효과)

  • Shin, Im-Sun;Jang, Yoon-Ok
    • Journal of Korean Home Economics Education Association
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    • v.24 no.1
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    • pp.85-104
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    • 2012
  • The purpose of this study was to carry out the career portfolio and the teacher-directed career exploration program in the unit of 'Industry and Career' of Technology·Home Economics and to find out how much those programs affect on career maturity and career identity in middle school students. The subjects were third-grade students who were selected at random from a middle school in Daegu. The subjects were divided into 60 for career portfolio group, 60 for teacher-directed group, and 60 for control group. Those programs were conducted totally in 9 sessions once or twice a week, and each session took 45 minutes. For pretest and post test, the questionnaire consisting of career maturity scale and career identity scale was used. To analyze data, ANCOVA was used and Scheffe test was conducted to examine significant differences between three groups. The main result of this study was the following : First, students who participate in the career portfolio and the teacher-directed career exploration program are more improved than those who have not been taught anything in determinacy and purpose of career maturity. Also, students who join in the career portfolio career exploration program are much more improved than those who join in the teacher-directed career exploration program in confidence and preparedness of career maturity. Second, students who join in the career portfolio career exploration program are more improved than those who join in the teacher-directed career exploration program in stability, goal directivity and assertiveness of career identity. Also students who participate in the lecture-oriented career exploration program are more improved meaningfully than those who have not been taught anything in the task orientation of career identity.

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Evaluation of Crack Behavior and Climate Monitoring of Ipseok-dae Columnar Joints and Jigong Neodeol Rock Blocks in Mudeungsan National Park (무등산국립공원 입석대 주상절리 및 지공너덜 암괴의 균열 거동과 기후 모니터링 평가)

  • Noh, Jeongdu;Kang, Seong-Seung
    • The Journal of Engineering Geology
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    • v.31 no.4
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    • pp.621-630
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    • 2021
  • This study evaluated cracks and climate monitoring in Ipseok-dae columnar joints and Jigong Neodeol rock blocks in Mudeungsan National Park. The rocks' state of cracking and their surface temperatures were measured alongside air temperature, relative humidity, and wind velocity. The maximum crack behavior in Ipseok-dae was 0.367 mm at one point, and showed a slight tendency at other points. One in Jigong Neodeol was within 0.15 mm and showed a stable state with little change. The surface temperature of the Ipseok-dae columnar joints was higher on the side exposed to sunlight than on the shaded side. All blocks of Jigong Neodeol rock showed similar temperatures. The air temperature showed a similar distribution for both rock types. The air temperature showed a similar distribution for both Ipseok-dae and Jigong Neodeol. The relative humidity was mostly between 20% and 60% in Ipseok-dae and was between 20 and 70% in Jigong Neodeol. Both areas had low wind speeds, with maxima of 5 m/s in Ipseok-dae and 3 m/s in Jigong Neodeol. As a result, it is evaluated that crack behavior in Ipseok-dae columnar joints and Jigong Neodeol rock blocks have maintained a very stable state so far. The surface temperature, temperature, relative humidity, and wind velocity of the two areas showed small difference depending on the season, indicating that they were affected to some extent by the season. From a long-term perspective, this can continuously affect the deformation of the Ipseok-dae columnar joints or Jigong Neodeol rock blocks. Therefore, in order to accurately evaluate their stability, it is considered that the current microscopic delamination and exfoliation or the propagation and expansion of cracks should be continuously measured.

An Analytical Study on the Seismic Behavior and Safety of Vertical Hydrogen Storage Vessels Under the Earthquakes (지진 시 수직형 수소 저장용기의 거동 특성 분석 및 안전성에 관한 해석적 연구)

  • Sang-Moon Lee;Young-Jun Bae;Woo-Young Jung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.6
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    • pp.152-161
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    • 2023
  • In general, large-capacity hydrogen storage vessels, typically in the form of vertical cylindrical vessels, are constructed using steel materials. These vessels are anchored to foundation slabs that are specially designed to suit the environmental conditions. This anchoring method involves pre-installed anchors on top of the concrete foundation slab. However, it's important to note that such a design can result in concentrated stresses at the anchoring points when external forces, such as seismic events, are at play. This may lead to potential structural damage due to anchor and concrete damage. For this reason, in this study, it selected an vertical hydrogen storage vessel based on site observations and created a 3D finite element model. Artificial seismic motions made following the procedures specified in ICC-ES AC 156, as well as domestic recorded earthquakes with a magnitude greater than 5.0, were applied to analyze the structural behavior and performance of the target structures. Conducting experiments on a structure built to actual scale would be ideal, but due to practical constraints, it proved challenging to execute. Therefore, it opted for an analytical approach to assess the safety of the target structure. Regarding the structural response characteristics, the acceleration induced by seismic motion was observed to amplify by approximately ten times compared to the input seismic motions. Additionally, there was a tendency for a decrease in amplification as the response acceleration was transmitted to the point where the centre of gravity is located. For the vulnerable components, specifically the sub-system (support columns and anchorages), the stress levels were found to satisfy the allowable stress criteria. However, the concrete's tensile strength exhibited only about a 5% margin of safety compared to the allowable stress. This indicates the need for mitigation strategies in addressing these concerns. Based on the research findings presented in this paper, it is anticipated that predictable load information for the design of storage vessels required for future shaking table tests will be provided.

Noodle- Making Properties of Domestic Wheats Cultivars (국내산 밀의 제면 적성에 관한 연구)

  • 남재경;한영숙;현영희;오지영
    • Korean journal of food and cookery science
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    • v.16 no.6
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    • pp.593-601
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    • 2000
  • Seven domestic wheat cultivars, Suwon 261, Suwon 265, Eunpa, Kobun, Alchan, Olgru, and Kumgang, and a standard wheat, ASW(Australian Standard White Wheat), were compared in noodle-making properties. The ash contents of domestic wheats and flours were 0.1-0.3% higher than that of ASW. Therefore, domestic wheats required the control of ash contents during milling process. The protein contents which suggest the flour gluten content were 10.32, 11.3, and 9.57% in Suwon 261, Suwon 265, and Kumgang cultivars, respectively. Valorimeter values of Eunpa, Olgru, and Kumgang which indicate the dough formation time and stability were similar to that of ASW. Resistance rate of domestic wheats was lower than that of ASW. Maximum viscosity in Amylograph for Eunpa, Olgru, and Kumgang were in the range of 500-800BU, which were suitable for making noodles. Increase in weight and volume of Olgru noodle was negatively correlated with protein content. Turbidity was not positively correlated with weight and volume increase, but domestic cultivars except Suwon 265 and Eunpa showed a similar turbidity with ASW. The mechanical properties of wet and dry noodles were evaluated by TPA test before and after cooking. Springiness and cohesiveness of wet noodles increased by cooking, and the domestic cultivars showed higher values than ASW. Springiness and cohesiveness of dry noodle were not increased by cooking in any cultivars. Gumminess, chewiness and hardness of domestic wheat cultivars showed higher values than that of ASW. In the tensile test, wet noodles showed no difference between domestic cultivars and ASW. But dry noodles of domestic wheat cultivars showed higher values than ASW. In the color test for lightness, redness and yellowness, there were no differences between flour and dough of domestic wheat cultivars and ASW. In the sensory evaluation, Kumgang wheat cultivar was the most preferred among the wet and dry noodles of other domestic wheat cultivars and ASW. These results suggested Kumgang wheat cultivar to be a practical wheat variety for noodle-making.

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Comparative Medium Term Results of Arthroscopic ACL Reconstruction with Quadrupled Semitendinosus Tendon versus BPB tendon (4겹의 반건양건과 골-슬개건-골을 이용한 관절경적 전방 십자 인대 재건술의 중기적 치료 결과 비교)

  • Kim, Hyoung-Soo;Park, Seung-Rim;Kang, Joon-Soon;Lee, Woo-Hyeong;Kim, Ki-Wook
    • Journal of the Korean Arthroscopy Society
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    • v.5 no.1
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    • pp.1-6
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    • 2001
  • Purpose : The purpose of this study was to compare the postoperative success and stability of arthroscopically assisted anterior cruciate ligament(ACL) reconstructions using central one third bone-patellar-tendon bone(BPB) autograft versus quadrupled semitendinos-us(ST) autograft as the medium term review. Materials and Methods : Eighty patients(40 BPBs,40 STs) with isolated ACL injury were available for a mean follow up of 49.4 months(BPB) and 48.8 months(ST). There was no significant difference between the two groups with respect to age and sex. We compare the final results between two groups with respect to subjective Lysholm score, objective laxity including anterior drawer test, Lachman test, pivot shift test, KT-2000 measurements and International Knee Documentation Committee(IKDC) evaluation system. Results : Postoperatively, positive anterior drawer test was found in $22.5\%\;and\;27.5\%$, positive Lachman test was found in $30.0\%$ and $25.0\%$ and positive pivot shift test was found in $15\%\;and\;20\%$ of the ST and BPB group, respectively(p>0.05). Mean side to side difference of KT-2000 at 20 lbs was 2.2 mm for the ST group and 2.1 mm for the BPB group. There was no significant difference between the two groups about Lysholm score(>0.05). Anterior knee pain was knee common in the BPB group. Eighty-three percent of the patients were nearly normal according to the IKDC grade in both groups. Conclusion : We consider that autogenous semitendinosus tendon is a good alternative subsititute in ACL reconstruction together with the bone-patellar tendon-bone autograft.

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