• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1201-1209
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• 2006

The purpose of this study was to isolate probiotic lactic acid bacteria (LAB) that produce bile salt hydrolase (BSH), and to evaluate its effects on serum cholesterol level. One-hundred-twenty bacterial colonies were initially isolated from human feces, and five strains were selected after screening based on their resistance to acids, tolerance against bile salts, and inhibitory activity on Escherichia coli. The Lactobacillus plantarum strain with the highest level of BSH activity was identified using 16S rRNA sequences, and was named L. plantarum CK 102. L. plantarum CK 102 at a level of 1.36$\times$10$^8$cfu/ml survived in pH 2 buffer for 6 h and exhibited excellent tolerance for bile salt. Coculturing the strain with E. coli in MRS broth resulted in strong inhibition against growth of E. coli at 18 h. Furthermore, the potential effect of CK 102 on serum cholesterol level was evaluated in rats. Thirty-two rats [Sprague-Dawley (SD) male, 129$\pm$l g, 5 weeks old] were divided into four groups of eight each. For six weeks, Group 1 was fed a normal diet (negative control); Group 2 was fed a cholesterol-enriched diet (positive control); Group 3 was fed a cholesterol-enriched diet plus L. plantarum CK 102 at 1.0$\times$10$^7$cfu/ml; and Group 4 was fed a cholesterol-enriched diet plus L. plantarum CK 102 at 5.0$\times$10$^7$cfu/ml. Blood samples were collected, serum lipids were analyzed, and weights of the organs were measured. Total blood cholesterol level, triglyceride, LDL-cholesterol, and free-cholesterol values were lower in rats that were fed 1. plantarum CK 102 than in those not fed L. plantarum CK 102. This cholesterol lowering effect implies that L. plantarum CK 102 could be utilized as an additive for health-assistance foods. In conclusion, these results suggest that the 1. plantarum CK 102 isolated could be used commercially as a probiotic.

• Asian-Australasian Journal of Animal Sciences
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• 제23권9호
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• pp.1236-1243
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• 2010

The aim of this study was to screen lactic acid bacteria for the fermentation of garlic and to assess the increase in inhibitory activity of garlic fermented against antibiotic-resistant pathogens for use as an animal feed supplement. We screened 45 strains of lactobacillus for the fermentation of garlic. Of these strains, 23 showed similar growth rates with or without allicin. Cultures of the 23 strains were mixed with an equivalent amount of garlic juice and incubated overnight at $37^{\circ}C$. The three strains with the lowest pH values were Lactobacillus paracasei KCTC 3169, L5 strain, and L. reuteri SW. Garlic juice fermented by the L5 strain more strongly inhibited antibiotic-resistant pathogenic bacteria than L. paracasei KCTC 3169, L. reuteri SW, or garlic juice itself. By examining carbohydrate utilization, morphologic properties and 16S rRNA gene sequences, we identified the L5 strain as Pediococcus pentosaceus and deposited it in the name of P. pentosaceus KACC 91419 into the Korea Agricultural Culture Collection. To identify the antimicrobial compound from the garlic filtrate fermented by P. pentosaceus KACC 91419, we fractionated P. pentosaceus KACC 91419 culture on a C18 column and checked the antimicrobial activity of fractions A6 to A10. Only fraction A9 showed inhibitory activity on Staphylococcus aureus. Comparing the mass spectra of the fractions with and without antimicrobial activity, we observed a single dominant product ion (m/z 157.99) from the fraction showing antimicrobial activity. Its molecular mass (157.99) was 2 atomic mass units less than that of allicin (162.02). This suggests that allicin might be converted to its derivative, which has antimicrobial activity, during fermentation by P. pentosaceus KACC 91419.

• Journal of Animal Science and Technology
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• 제44권5호
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• pp.617-624
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• 2002

일년생 콩과목초는 가축에게 단백질 원료와 토양에 질소 비료로 이용되고 있으나 품종의 선택과 관리기술은 어려움이 많다. 따라서 본 시험은 콩과목초의 우량품종을 선발하고 조사료 가치를 평가하기 위하여 1년간 (1999${\sim}$2000) 2지역인 경기 수원과 충남 성환에서 수행하였다. 일년생 콩과목초의 유식물 활력과 내도복성은 모든 품종에서 8점 이상으로 양호하였다. 그러나 원동률에서는 crimson clover와 rose clover는 월동을 하였으나, persian clover의 ‘Lazer; 및 'Nitro' 품종은 각각 35.9%, 및 9.1%로 거의 월동이 되지 않았다. Crimson clover의 ’Tibbee' 및 'Contea' 품종은 각각 5월 4일과 6일에 개화하였으며, rose clover의 ‘Bolta balansa’ 품종은 4월 29일에 개화하였다. 콩과목초의 ha당 건물수량은 crimson clover의 ‘Contea' 품종이 4,218kg/ha로 공시품종 중에서 가장 높았으며, crimson clover의 ’Tibbee' 품종과 rose clover의 ‘Bolta balansa' 품종이 각각 3,874 및 3,828kg/ha로 높은 수량을 보였다. ADF 및 NDF 함량으로 계산한 상대사료가치는 공시품종 모두가 125 이상으로 높은 품질을 나타내었다. 이상의 결과를 볼 때 crimson clover와 rose clover는 월동률이 높고 건물수량이 많아 중부지방에서 일년생 콩과목초로 권장할 수 있으나, persian clover는 월동률이 낮아 중부지방에서 일년생 콩과목초로 이용하기에는 문제가 있었다.

• 대한환경공학회지
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• 제22권7호
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• pp.1193-1203
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• 2000

본 연구는 흡착에 의한 Cd(II)의 제거를 위하여 일본 Diaion사에서 제조되고 있는 강산성양이온 교환수지(SK1B)를 흡착제로 사용하여 흡착평형실험, 탈착실험 및 흡착속도실험을 수행하였다. 흡착평형실험에서는 흡착능에 미치는 pH와 온도의 영향을 알아보았고 흡착등온식을 산출하였으며, 탈착실험에서는 재생회수에 대한 수지의 재생율의 변화에 대해서 알아보았다. 흡착속도실험에서는 수지를 미분층 반응기에 채워 유량별로 초기제거속도를 구하여 경막저항이 최소가 되는 최적유량을 구하였으며, 이 최적유량에서 흡착속도실험을 수행하여 총괄흡착속도식을 구하였다. 용액의 pH를 변화(2~7)시켜 제조하여 수지를 투여한 결과 pH가 증가할수록 흡착능이 증가하였으며 pH 6 이상에서는 흡착능이 일정한 경향을 나타내었다. 흡착능에 미치는 온도의 영향은 $10{\sim}50^{\circ}C$ 범위에서 온도가 증가할수록 흡착능도 증가함을 알 수 있었다. 회분식실험을 통해 얻은 자료를 각 흡착등온식에 적용해 본 결과 본 실험의 농도 영역(5~15ppm)에서는 Freundlich 흡착등온식과 Sips 흡착등온식이 Langmuir 흡착등온식보다 더 %편차가 적었다. 탈착제로서 0.01~2N 농도의 HCl 수용액을 사용할 경우에는 탈착제의 농도가 진할수록 흡착제의 재생율이 높았으며 재생 반복회수가 늘어날수록 재생율이 약간씩 감소하였다. 미분층 반응기를 이용한 연속공정실험($25{\pm}5^{\circ}C$)에서 경막확산저항이 최소가 되는 최적유량 $564m{\ell}/min$에서 수행한 수지에 대한 Cd(II) 수용액의 총괄흡착속도식은 다음과 같이 표현될 수 있다. $r=1.3785C_{fc}^{1.2421}-2.0907{\times}10^{0.0746C_i}\;q_e^{0.0121C_i-0.0301}$

• 미생물학회지
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• 제51권4호
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• pp.419-426
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• 2015

가축산업분야에서 항생제의 사용이 금지됨에 따라, 질병 예방을 통한 축산농가의 생산성 향상을 위해 사료첨가제인 미생물제재의 개발과 같은 예방적 수단이 필요하게 되었다. 본 연구는 가축의 생산성을 높이기 위해 사료 분해 능력이 좋고 항균활성이 뛰어난 포자 형성 Bacillus 균주 3종인 B. sutilis LCB7, B. licheniformis SHS14, B. amyloliquefaciens LCB10을 우수 균주로 선발하였다. 최종적으로 선발한 Bacillus 3종을 1:1:1 비율로 혼합하여 혼합 종균을 제조하여 항균시험(in vitro) 결과, 단일 3종 및 lincomycin과 비교하여 유사한 활성을 보여주었으며, 송아지를 이용하여 항균활성 시험(in vivo)을 실시한 결과에서도 lincomycin 투여 대비 90% 수준의 높은 활성을 보여주었다. 개발한 혼합 종균의 안정적 보존을 위해 혼합 종균을 제조하여 다시 증균을 통하여 미생물군집 분석을 통하여 확인한 결과, 초기 군집비율과 증균 후 군집비율이 매우 유사하게 유지되었다. 이로서 본 연구에서는 선발된 Bacillus 균주 3종을 이용하여 제조한 혼합 종균이 사료첨가제용 미생물제재로서 이용 가능함을 최종 확인하였다.

• Journal of Oral Medicine and Pain
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• 제20권2호
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• pp.429-447
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• 1995

This study was designed to determine the most effective concentration of fluoride and levels of laser irradiation for the remineralization of decayed teeth. After irradiation with a pulsed Nd:YAG laser and the topical application of fluoride, phosphate and fluoride concentration in enamel were measured. And then the changes on surface enamel using an scanning electron microscope were observed. Samples by extraction healthy, permanent, mandibular bovine teeth with no caries were obtained. Among them 371 healthy samples were selected and artificial carious lesions were made. 20 samples were assigned to each experimental group. After irradiation with a pulsed Nd:YAG laser with total energy densities of 10J/$\textrm{cm}^2$, 20J/$\textrm{cm}^2$ for each group. On the teeth, 2% NaF, 1.9% NH4F, 1.6% TiF4 Elmex gel(amine fluoride) and 1.23% APF gel were applied. After pH circulatory procedures, concentrations of fluoride with and Ionalyzer (Orion Research, Model 901, USA) and phosphates with an Uv/V is spectrophotometer (Uvikon 860, Kontrom Co, Switzerland) were measured. By etching the teeth in layers and measuring fluoride concentrations, a profile of fluoride penetration according to depth could be developed. And also the changes on the surface of the enamel using an electron scanning microscope were observed. The comparative analysis yielded the following results : 1. Phosphate concentration was low in all groups compared with the control group except for teeth treated Elmex gel, irradiated with 10J/$\textrm{cm}^2$ and 30J/$\textrm{cm}^2$ energy densities. Teeth treated with APF gel and 30J/$\textrm{cm}^2$ irradiation gad the lowest phosphate concentration. 2. Among all groups, fluoride concentrations in tooth enamel were highest in APF gel and NaF groups irradiated at 30J/$\textrm{cm}^2$. The APF gel group had the highest fluoride concentrations across all energy densities. 3. In the APF gel group, and the NaF group, the greater the energy density of the laser, the higher the fluoride concentrations in the enamel. 4. In all groups, the concentration of fluoride in the enamel by depth tended to decrease with depth. 5. Under the scanning electron microscope, under the condition of irradiation with 20J/$\textrm{cm}^2$, enamel crack was detected for the first time. In the NH4F group, spherical deposits were found on the surface of the enamel, and in the TiF4 group the surface of enamel was covered with an irregular, thin membranous mass in places. In the APF gel and NaF groups irradiated with 10J/$\textrm{cm}^2$, spherical and irregular particles covered the teeth. When these groups were irradiated at 20J/cm2, they were covered with amorphous crystals. These results suggest that one could obtain more effective anticariogenic effects without damage to teeth when less than 20J/$\textrm{cm}^2$ energy densities and APF gel are used.

• 한국세라믹학회지
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• 제44권12호
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• pp.740-746
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• 2007

The potential candidates for IT-SOFCs cathode materials, $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ (BSCF) and $La_{0.6}Ba_{0.4}Co_{0.2}Fe_{0.8}O_{3-{\delta}}$ (LBCF) powders, were synthesized by a EDTA-citrate combined method from $Sr(NO_3)_2$, $Ba(NO_3)_2$, $La(NO_3)_3{\cdot}6H_2O$, $Co(NO_3)_2{\cdot}6H_2O$, $Fe(NO_3)_3{\cdot}9H_2O$, citric acid and $EDTA-NH_3$. The cathode performance of symmetrical electrochemical cells consisting of BSCF-GDC or LBCF-GDC composite electrodes and a GDC electrolyte was investigated using by AC impedance spectroscopy at the temperature range of 500 to $700^{\circ}C$. It was found that a single phase perovskite could be successfully synthesized when the precursor is heated at $850^{\circ}C$ for 2 h. Due to thermal expansion mismatch between BSCF and GDC, the composite cathodes with lower GDC content than 45 wt% were peeled off from the GDC electrolyte and their electrode polarization resistance was estimated to be high. The thermal expansion coefficient of BSCF-GDC composites was decreased with increasing the GDC content and the electrode peeling off did not occur in BSCF-45 and 55 wt% GDC composites. BSCF-45 wt% GDC composite electrode showed the lowest area specific resistances (ASR) of 0.15 and $0.04{\Omega}{\cdot}cm^2$ at 600 and $700^{\circ}C$, respectively. On the other hand, LBCF-GDC composite cathodes showed higher ASR than the BSCF-45 and 55 wt% GDC and their cathode performance were decreased with the GDC content.

• 콘크리트학회논문집
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• 제25권1호
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• pp.73-80
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• 2013

이 연구는 폴리머 시멘트 슬러리로 도장한 도장철근의 부착강도 개선에 영향을 미치는 초기재령에서의 PCS 도장재 배합에 관한 연구로 폴리머의 종류, 시멘트의 종류, 폴리머 시멘트비, 도장재의 양생재령, 도장두께 등을 변화시켜 배합을 설정하여 부착강도 시험을 실시하였다. 이 연구 결과, PCS 도장철근의 부착강도는 거의 모든 배합에서 도장하지 않은 보통철근 및 에폭시철근에 비해 높은 부착강도를 나타냈다. 도장철근의 최대 부착강도는 보통철근에 비해 1.52배, 에폭시 철근에 비해 1.58배로 높게 나타났으며, 도장두께는 $100{\mu}m$에서 우수하였으며, 시멘트는 초조강 시멘트, 폴리머는 EVA, 폴리머 시멘트비는 80%~100% 범위에서 우수한 부착강도를 나타냈다. 또한 양생재령에 있어서는 3시간의 단시간 양생에 의한 부착강도도 양생재령 1일 및 7일에 비해 열악하지 않고 동등이상의 부착강도를 나타내 실제 현장에서의 사용성면에서 유리한 것으로 볼 수 있다.

• Clinical and Experimental Pediatrics
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• 제62권12호
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• pp.450-455
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• 2019

Background: Lipid accumulation product (LAP) is associated with the presence and severity of nonalcoholic fatty liver disease (NAFLD) in adults. Purpose: Here we evaluated the ability of LAP to predict NAFLD in obese children. Methods: Eighty obese children (38 girls; age 6-18 years) were included. Anthropometric measurements and biochemical values were obtained from the patients' medical records. LAP was calculated as [waist circumference (WC) (cm) - 58]×triglycerides (mmol/L) in girls; [WC (cm) - 65]×triglycerides (mmol/L) in boys. The minLAP and adjLAP were described (3% and 50% of WC values, respectively) and the total/high-density lipoprotein cholesterol index (TC/HDL-C) was calculated. NAFLD was observed on ultrasound, and patients were divided into 3 groups by steatosis grade (normal, grade 0; mild, grade 1; moderate-severe, grade 2-3). The area under the curve (AUC) and appropriate index cutoff points were calculated by receiver operator characteristic analysis. Results: LAP was positively correlated with puberty stage (rho=0.409; P<0.001), fasting insulin (rho= 0.507; P<0.001), homeostasis model assessment of insulin resistance (rho=0.470; P<0.001), uric acid (rho=0.522; P<0.001), and TC/HDL-C (rho=0.494; P<0.001) and negatively correlated with HDL-C (rho=-3.833; P<0.001). LAP values could be used to diagnose hepatosteatosis (AUC=0.698; P=0.002). The LAP, adjLAP, and minLAP cutoff values were 42.7 (P=0.002), 40.05 (P=0.003), and 53.47 (P= 0.08), respectively. For LAP, the differences between the normal and mild groups (P=0.035) and the normal and moderate-severe groups were statistically significant (P=0.037), whereas the difference between the mild and moderate-severe groups was not (P>0.005). There was a statistically significant difference between the normal and mild groups for adjLAP (P=0.043) but not between the other groups (P>0.005). There was no significant intergroup difference in minLAP (P>0.005). Conclusion: LAP is a powerful and easy tool to predict NAFLD in childhood. If LAP is ≥42.7, NAFLD should be suspected. This is the first study to assess LAP diagnostic accuracy for childhood obesity.

• Pediatric Infection and Vaccine
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• 제15권2호
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• pp.167-173
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• 2008

목 적 : 저자들은 8년간 단일기관에서 경험한 소아 폐외결핵 환자들의 임상적, 미생물학적 특성을 알아보고자 하였다. 방 법 : 2000년 1월부터 2007년 12월까지 가톨릭대학교 인천성모병원에서 폐외결핵으로 진단받은 15세 이하의 환자들의 의무기록과 검사소견을 후향적으로 조사하였다. 결 과 : 총 109명의 결핵환자 중 폐외결핵은 12명으로 11%를 차지하였다. 총 결핵환자에 대한 폐외결핵 환자의 비율은 2006-2007년에 20%로 그전에 비하여 증가하였다. 남녀 비는 1.4:1이었으며 진단시 평균 연령은 9.2세(3개월-15세)였다. 침범부위는 늑막이 5명(41.6%)으로 가장 많이 발생하였고 중추신경계 3명, 속립성 2명, 골관절 1명, 위장관1명 순이었다. 입원했을 때의 주증상은 발열이 11명(91.6%)으로 가장 많이 나타났으며 총 발열일수는 평균 15.8일(0-47일)이었다. 결핵균 도말 검사는 33.3%, 배양검사는 41.6%, 중합효소연쇄반응 검사에서는 41.6%의 환자에서 양성이었다. 항결핵제 감수성 검사를 시행한 5명 중 4명(80%)에서 1개 이상의 약제에 내성을 보였다. 11명은 합병증 없이 치료되었고 1명은 치료 도중 사망하였다. 결 론 : 본 연구 결과 연구 기간 중 2006-2007년에 총 결핵환자에 대한 폐외결핵 환자의 비율이 이전에 비하여 증가하였다. 또한 소아 폐외결핵이 폐결핵에 비해 미생물학적 진단률이 낮고 항결핵제 내성률이 증가하는 추세임을 알 수 있었다.