• Clinical and Experimental Reproductive Medicine
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• 제49권4호
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• pp.259-269
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• 2022

Objective: Animal-free scaffolds have emerged as a potential foundation for consistent, chemically defined, and low-cost materials. Because of its good potential for high biocompatibility with reproductive tissues and well-characterized scaffold design, we investigated whether polyglycolic acid (PGA) could be used as an animal-free scaffold instead of natural fibrin-agarose, which has been used successfully for three-dimensional human endometrial cell culture. Methods: Isolated primary endometrial cells was cultured on fibrin-agarose and PGA polymers and evaluated various design parameters, such as scaffold porosity and mean fiber diameter. Cytotoxicity, scanning electron microscopy (SEM), and immunostaining experiments were conducted to examine cell activity on fabricated scaffolds. Results: The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay and SEM results showed that endometrial cells grew and proliferated on both scaffolds. Immunostaining showed cytokeratin and vimentin expression in seeded cells after 7 days of culture. On both scaffolds, an epithelial arrangement of cultured cells was found on the top layer and stromal arrangement matrix on the bottom layer of the scaffolds. Therefore, fibrin-agarose and PGA scaffolds successfully mimicked the human endometrium in a way suitable for in vitro analysis. Conclusion: Both fibrin-agarose and PGA scaffolds could be used to simulate endometrial structures. However, because of environmental and ethical concerns and the low cost of synthetic polymers, we recommend using PGA as a synthetic polymer for scaffolding in research instead of natural biomaterials.

• 한국동물위생학회지
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• 제24권1호
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• pp.31-41
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• 2001

This study was carried out to identify causative agents from california mastitis test(CMT) positive mastitic milk, and to examine the antimicrobial susceptibility of 50 heads in Seongju and Chilgok area of Gyeongbuk province. Sulfadimethoxine sodium(SMS) was intramuscularly administered once to four mastitis Infected dairy cattle at the rate of 10mg/kg body weight. After injection of SMS, the depletion rate of serum and milk from the cattle were periodically measured for five days. The CMT positive number from 50 heads showed 46% and that of 200 quarters was 47(23.5%). From 39 quarters of 47 heads 39 different microorganisms were identified. These organisms were classified into 12 species : Staphylococcus aureus 8(20.5%), Sta hemolyticus 6(15.4%), Streptococcus bovis 4(10.3%), Sta hyicus 3(7.7%), Sta epidemidis. Sta xylosus, Sta sciuri 2(5.1%), Str agalactiae 2(5.1%), Escherichia coli(10.3%), three Enterobacter cloacae(7.7%), two Ent aerogenes(5.1%) and one Salmonella spp(2.6%). As the results of antibiotic susceptibility test, gentamicin(Gm, 11 species 27 strains, 69.5%), cephalotin(Cf, 9 species 24 strains, 61.5%), sulfamethoxazole(Stx, 8 species 14 strains, 43.6%), tetracycline(Tc, 8 species 14 strains, 35.9%), and streptomycin(Sm), lincomycin(Lm), cefoperazon(Cp) and penicillin(Pc) have a highly resistance(7.7% ～5.1%). However, carbenicillin (Cb), amikacin(Ah) have no susceptible for all drugs. The mean residual concentration of SMS in serum according to the time lapsed were showed 33.964 $\pm$ 4.435ppm at the 4 hours after intramuscularly injection(AII). It was significantly(p<.05) decreased to 6.596 $\pm$ 3.402, 0.217 $\pm$ 0.119 and 0.005 $\pm$ 0.004ppm at the 1st, 3rd and 5th day AII. The mean concentration of SMS in milk was significantly(p<.05) decreased from 0.920 $\pm$ 0.42ppm to 0.084 $\pm$ 0.016ppm between 8 hours and 1 day AII. As the results of this experiments, sulfadimethoxine was residued at the level of no less than 0.01ppm in milk on the 2nd day AII. Thus, this results would be able to be used the basic index for prevention of sulfonamides residue in milk after treatment of dairy mastitis.

• Archives of Plastic Surgery
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• 제51권2호
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• pp.251-257
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• 2024

Background Plastic surgery has developed to benefit in a variety of challenging areas formerly handled by other disciplines. Medical students do not have a clear picture of plastic surgery as a career due to lacking scope, clinical practice, and understanding of plastic surgery as a clinical area of expertise, including general practitioners, nursing staff, medical trainees, and the general public, and misconceptions about the extent of reconstructive and plastic surgery. Methods A cross-sectional observational study was conducted on Kuwait University Medical students (2nd-7th Years) over a period of 1 month. A questionnaire and a consent form were provided to eligible students. The inclusion criteria were Kuwait University Medical students from 2nd to 7th Years with signed consent form. The response was collected via email sent in coordination with the Vice Dean of Student Affairs in the Faculty of Medicine. Using statistical package for the social sciences, responses were statistically analyzed. Pearson's chi-square test was used to calculate p-values, where p < 0.05 was considered statistically significant. Results A total of 244 eligible medical students, 121 males and 123 females, were included in the study, with a mean age of 21 (±2) years. Similarly, 126 (51.6%) were preclinical students (2nd-4th-year students), while 118 (48.4%) were clinical students (5th-7th-year students). About 79.8% of medical students believed that plastic surgery plays an essential role in trauma management, whereas 9.2% did not consider plastic surgery significant for trauma management. This study found that only 15.5% of medical students were interested in enrolling in plastic surgery residency after graduation, while 47.1% of students did not consider plastic surgery residency after graduation. However, 37.4% were uncertain. The two most driving factors in deciding on plastic surgery residency were expected income (61.8%) and lifestyle (14.3%). Conclusion Improving medical students' education quality can enhance their perception and awareness of plastic surgery. Students should be taught the broader scope of plastic surgery. The inclusion of formal training during undergraduation is the essence of time and should be added to or improved during plastic surgery rotations with more emphasis on reconstructive and hand/peripheral nerve surgery. Student-led interest groups can be a useful tool for educating students about their specialty.

• 한국축산식품학회지
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• 제38권1호
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• pp.203-208
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• 2018

The objective of this study was to investigate the pathogenicity and antimicrobial resistance of foodborne pathogens isolated from farmstead cheeses. Twenty-seven isolates, including 18 Bacillus cereus, two Escherichia coli, and seven Staphylococcus aureus, were subjected to polymerase chain reaction (PCR) to detect virulence genes and toxin genes, and the antibiotic resistances of the isolates were determined. All E. coli isolates were determined by PCR to be non-pathogenic. Among the 18 B. cereus isolates, 17 isolates (94.4%) were diarrheal type, as indicated by the presence of nheA, entFM, hbIC, cytK and bceT genes, and one isolate (5.6%) was emetic type, based on the presence of the CER gene. Among the seven S. aureus isolates, three (42.9%) had the mecA gene, which is related to methicillin-resistance. Most B. cereus isolates (94.7%) showed antibiotic resistance to oxacillin and penicillin G, and some strains also showed resistance to ampicillin (26.3%), erythromycin (5.3%), tetracycline (10.5%), and vancomycin (5.3%). These results indicate that microbial food safety measures for farmstead cheese must be implemented in Korea because antibiotic resistant foodborne pathogens, with resistance even to vancomycin, harboring virulence genes were found to be present in the final products of farmstead cheese.

• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.2043-2048
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• 2015

Bacillus thuringiensis microbial insecticide products have been applied worldwide. Although a few cases of B. thuringiensis foodborne illness have been reported, little is known about the toxigenic properties of B. thuringiensis isolates. The aims of this study were to estimate the pathogenic potential of B. thuringiensis selected from microbial insecticide products, based on its possession of toxin genes and production of enterotoxins. Fifty-two B. thuringiensis strains selected from four kinds of microbial insecticide products were analyzed. PCR assay for detection of toxin genes and immunoassay for detection of enterotoxins were performed. The hemolysin BL complex as a major enterotoxin was produced by 17 (32.7%), whereas the non-hemolytic enterotoxin complex was detected in 1 (1.9%) of 52 B. thuringiensis strains. However, cytK, entFM, and ces genes were not detected in any of the tested B. thuringiensis strains. The potential risk of food poisoning by B. thuringiensis along with concerns over B. thuringiensis microbial insecticide products has gained attention recently. Thus, microbial insecticide products based on B. thuringiensis should be carefully controlled.

• 한국산림과학회지
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• 제110권4호
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• pp.504-515
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• 2021

세뿔투구꽃의 서식에 영향을 미치는 환경인자들과의 관계를 규명하기 위해 MexEnt 모형을 구동하여 21개의 환경인자를 평가한 결과 0.6 이상의 유의성 있는 AUC값을 가지고 있는 14개의 환경인자는 임령, 임목축적, 임분밀도, 고도, 지형, 지형습도지수, 일사량, 토성, 1월 평균기온, 4월 평균기온, 연평균 기온, 1월 평균 강수량, 8월 평균 강수량, 연평균 강수량이었다. 주요 14개 설명 인자들의 반응 곡선에 의하면 백운산 내 세뿔투구꽃은 해발고도가 600 m 이하의 낮은 지대로 내려갈수록 서식에 적합하다는 결과를 보이고 있었으며, 경사가 서식지에 미치는 영향은 낮았다. 임분 밀도는 밀, 지형은 계곡과 가까운 지역을 선호하였으며, 방위는 북동쪽에 대한 분포 비중이 높았다. 영급은 5영급을 기준으로 낮을수록 출현 확률이 높게 나타났다. 본 연구 지역의 세뿔투구꽃이 선호하는 일사량은 1.2 MJ/m²이며, 지형습도지수 값은 4.5를 기준으로 값이 낮아질수록 출현 확률이 낮아지고 기준 값이 높아질수록 출현 확률이 높아지는 양의 관계가 성립되었는데 임계수치는 7.5였다. 토양환경 분석결과 점토에서 사질양토로 갈수록 세뿔투구꽂의 존재확률이 증가하고 있었고 1월 평균기온이 -4.4℃~-2.5℃, 4월 평균기온이 8.8℃~10.0℃, 연평균 기온은 9.6℃~11.0℃인 지역을 서식에 적합한 주요 서식지로 분류할 수 있었다. 세뿔투구꽃은 연평균 강수량이 1,670~1,720 mm지역으로 8월 평균 강수량이 350 mm 이상 되는 지역에서부터 출현하기 시작했으며, 390 mm까지는 일정 부분 강수량이 높아질수록 선호하는 서식지로서의 가치를 가지고 있는 것으로 분석되었다. 분포적 의미를 갖는 결과 값이 75% 이상인 잠재서식지의 면적은 202 ha로 백운산 연구 대상지의 1.8%였다.

• 한국식품위생안전성학회지
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• 제38권4호
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• pp.217-227
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• 2023

최근 1인 가구, 맞벌이 가정의 급격한 증가로 인한 인구·사회학적 변화의 영향으로 즉석 반찬류의 소비가 빠르게 증가하고 있다. 이들 식품은 별도의 가열 등의 처리없이 조리되거나 조리 후 상온에서 보관되는 경우가 많아 미생물 오염에 매우 취약하다. 이에 본 연구에서는 즉석 반찬류의 미생물 오염 위험도를 분석하여 반찬류의 위생상의 문제점을 파악하고, 보관온도에 따른 미생물 품질변화를 조사하였다. 2022년 경상남도 7개 지역의 대형할인점에서 구입한 반찬류 100건에 대해 조리방법별로 식중독 윈인균과 위생지표균 검사를 진행하였다. 식중독 원인균 검사에서 Bacillus cereus는 51건(51.0%, 51/100), Clostridium perfringens는 3건(3.0%, 3/100)이 분리되었지만, 식품공전의 공통기준 및 규격 범위를 초과하는 제품은 없었다. 총 51개의 B. cereus 분리균주에서 5종류의 장내독소와 1종류의 구토독소를 분석한 결과, 장내독소 entFM, nheA, hblC, cytK, bceT 유전자의 보유율은 100.0%, 94.1%, 58.8%, 56.9%, 41.2% 순으로 각각 확인되었고, 구토 독소인 CER 유전자는 2.0%만이 보유하고 있었다. 총 3개의 C. perfringens 분리균주에서 식중독을 일으키는 독소 유전자(cpe)는 검출되지 않았다. 위생지표균 검사에서 김치류, 생채류, 젓갈류, 절임류, 나물류, 조림류 순으로 일반세균과 대장균군이 높게 검출되었다. 반찬류의 보관온도(4℃와 20℃)에 따른 일반세균수의 변화는 20℃에 보관할 시 젓갈류를 제외한 대부분의 반찬류에서 증가하는 경향을 보였다. 반찬류는 구입 즉시 냉장보관할 것을 권장하며, 시중에 유통되는 반찬류 제품의 위험성과 안전성을 평가하고 관리방안 제시를 위해 지속적인 모니터링과 추가 연구가 필요한 것으로 사료된다.

• 한국식품영양과학회지
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• 제44권12호
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• pp.1895-1904
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• 2015

본 연구에서는 건당 환자수가 높아 식품안전관리 우선순위가 높은 단체급식소의 식품, 조리도구 및 환경에서 식중독균을 분석하고 이들 미생물의 병원성 인자 및 항생제 내성을 확인하여 미생물 위험분석을 위한 기본정보를 제공하고자 하였다. 경기도 소재 총 8개(농촌 3, 도시 4 및 벽지 1) 학교급식소에서 식품 시료(n=66), 조리도구(n=44) 및 환경 시료(n=56) 등 총 179점의 시료를 채취하여 지표세균 및 식중독균을 분석하였다. 식품 시료에서 총균수는 평균 4.7 log CFU/g, 최대 8.1 log CFU/g으로 대장균군의 평균 오염도 3.1 log CFU/g, 최대 오염도 4.0 log CFU/g으로 높았다. 선반 및 개수대 등 환경 시료의 총균수는 평균 2.7 log CFU/g, 최대 4.1 log CFU/g으로 식품 시료보다 낮은 수준으로 분석되었으나 대장균의 경우 평균 4.0 log CFU/g, 최대 5.4 log CFU/g으로 식품 시료보다 오염 수준이 높아 환경으로 부터의 교차오염 가능성을 배제할 수 없었다. 병원성 미생물 중 Bacillus cereus의 정량분석 결과 식품(원료, 조리단계 및 조리식품 포함) 시료에서 평균 2.1 log CFU/g, 최대 4.1 log CFU/g으로 분석되었으나, 이 중 조리된 식품의 오염도는 10,000 CFU/g 이하로 식품공전의 기준 이하로 오염되어 있었다. Escherichia coli는 식품 중 조리 전 시료(n=14)에서만 검출율 35.7%로 분석되었으며 조리단계의 식품, 조리도구 및 환경 시료에서는 검출되지 않았다. Staphylococcus aureus의 경우 조리 전 식품 원료(n=14)의 21.4%에서 검출되었으며 환경 시료(냉장고 손잡이)에서 1건 양성으로 검출되었고, 조리단계의 식품, 조리도구 및 환경 시료에서는 검출되지 않았다. 그 외 Clostridium perfringens, Listeria monocytogenes, Salmonella spp., Vibrio parahaemolyticus는 분석된 모든 시료에서 모두 음성이었다. 분리된 B. cereus의 독소유전자(hblACD, nheABC, entFM, cytK enterotoxin gene)를 분석한 결과 구토 유발 독소인 ces는 모두 음성이었으나 분석된 86주 모두 적어도 1종 이상의 설사 유발 독소유전자가 검출되었으며 66.2%의 균주는 설사 유발 독소유전자를 모두 보유하고 있었다. 식품과 환경에서 분리한 S. aureus(n=16)의 장독소 생성 유전자를 분석한 결과 모두 1종 이상의 독소유전자가 검출되었다. 전형적인 장독소유전자 중에서는 sea만 검출되었으며, 독소충격증후군 toxin(tst) 유전자는 모든 분리주에서 검출되지 않았다. 집단 식중독 발생 시 초기 진료에 결정적 영향을 주는 항생제 내성 여부를 분석한 결과 E. coli(n=41)의 92.7%는 분석한 항생제 16종에 대해 내성을 보이지 않았고 cefazolin에 대한 내성률이 4.9%로 가장 높았으며, 1개 균주에서만 2개 항생제에 대해 다제내성을 보여 국내외 항생제 내성률보다 낮았다. S. aureus(n=16)는 시험한 19종 항생제 중 gentamicin에 대한 내성률이 62.5%로 가장 높았으며 일부 균주에서 2주 항생제에 대해 다제내성이 관찰되었다. 한편 단체 급식소 2개소의 조리도구와 환경 중 미생물 군집을 분석한 결과 특정균이 도구와 환경에서 중복 검출되어 도구와 환경 중 교차오염 가능성을 간접적으로 시사하였다. 이와 같이 본 연구에서 단체급식소 식품, 조리도구 및 환경 중 위생지표균과 병원성 미생물의 오염패턴을 분석하고 분리된 균주의 독성인자와 항생제 내성 정보를 분석하였다. 관련 정보는 단체급식소 미생물 위험분석과 이를 바탕으로 사전적, 정량적 안전관리 기술 개발에 활용 가능할 것으로 사료된다. 한편 식중독 유발의 다른 원인인 바이러스류와 기타 원인에 대한 연구는 진행되지 않아 추가 연구가 필요하다.

• 대한두경부종양학회지
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• 제23권1호
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• pp.26-31
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• 2007

Background and Objectives：Microvascular free flap reconstruction has been revolutionized in last two decades, and became a standard option in the reconstruction of head and neck defects. We intended to review our experiences of 51 microvascular free flap for head and neck defects during 5-year period and to analyze the types of flaps according to primary sites, success and complication rates. Subjects and Methods：From Oct. 2001 through Dec. 2005, fifty one free flap reconstructions were performed in forty nine patients at ENT department of Soonchunhyang university bucheon hospital. Primary sites, pathology, T-stage, operative time, time interval of oral feeding, and various reconstructive factors such as recipient and donor vessels, free flap related complications, failure rates and salvage rates were retrospectively analyzed. The relation between complication rates and preoperative risk factors were statistically analyzed. Results：Methods of reconstruction were radial forearm free flap(RFFF)(n=28, 54.9%), anterolateral thigh free flaps(n=9, ALTFF)(17.6%), rectus abdominis free flap(n=7, RAFF)(13.7%), jejunal free flap(n=5, JFF)(9.8%), and miscellanous(n=2, 4.0%) in order. In free flap related complications, failure of free flap occurred in seven cases(13.7%) and pharyngocutaneous fistula occurred in five cases(9.8%) among fifty one free flaps. The overall success rate of free flaps was 86.3%. Salvage of free flaps was possible only one among eight cases(12.5%). In positive preoperative risk factor groups, failure of free flap was higher than in negative risk factor group. However, it was not statistically significant. Conclusion：We confirmed that free flap reconstructions are highly versatile and reliable options for use in the reconstruction of various soft tissue defects of the head and neck. Free flaps have gained great popularity given its versatility, ability for a two-team approach, and minimal donor site morbidity. However, complications related to microvascular surgery may be overcome by increased surgical experience and by intensive flap monitoring in early postoperative period.

• 한국동물위생학회지
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• 제20권2호
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• pp.143-150
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• 1997

Total viable cells and lactose non-fermenting cells were counted from animal feedstuffs (n=65). And isolation of Gram negative lactose nonfermenting enterobacteria and antibiotics susceptibility of isolates were performed. 1. The ranges of total viable cells / lactose non-fermenters in animal feedstuffs from Korean cattle were counted as 9$\times$$10^4$-1$\times$$10^7$ / 1$\times$$10^2$-6$\times$$10^3$, milking cow as 1$\times$$10^4$-2$\times$$10^8$ / 2$\times$$10^2$-8$\times$$10^3$, pig as 1$\times$$10^4$-1$\times$$10^6$ / 2$\times$$10^2$-6$\times$$10^3$, and chicken as 7$\times$$10^4$-1$\times$$10^9$ / 4$\times$$10^2$-1$\times$$10^5$ cfu/g, respectively. 2. Among the 214 isolates from feedstufs, 87 from Chinan(n=23), 66 from Changsu (n=23) and 61 from Mooju(n=19) were isolated. Of these isolates, 60 from pigs (n: 19), 51 from milking cows(n=15), 45 from chikens(n=11) and 58 from Korean cattle(20) were isolated. 3. Among the 6 genuses of Gram negative lactose nonfermenting enterobacili, Salmonella sp, Y pseudotuberculosis, Ent agglomerans and Sal choleraesuis were frequently encountered. 4. A majority of isolates were sensitive to 19 antibiotics, singly or in combination. These isolates were completely susceptible to Cp, Gm, Imp and Pi, 93% to Ak and To, 73% to Cax and Ts, 66% to Cft and Tim, 46-53% to Caz, Cf and Cz, 33-40% to Am, Azt, Cfz and Ti, and 6% to Cfx, in order, but not susceptible to Crm. 5. Among the antibiotic resistant strains, a total of 23 resistant patterns was noted, and of these Crm 40(18.7%), Am Cf Cfx Cfz Crm Ti 27(12.6%), each of Azt Ctx Crm and Azt Cax Caz Cft Cfx Crm 22(10.3% ) were frequently encountered.