• 한국임상약학회지
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• 제7권2호
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• pp.86-90
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• 1997

This study was to find a more accurate method fur measuring small vancomycin dosages which are commonly used in neonates by comparing single and double dilution method. For single dilution method, 500 mg of vancomycin powder was accurately measured and reconstituted with 5 ml of distilled water to make a concentration of 100 mg/ml. Volumes of 0.05, 0.1, 0.15, 0.2, 0.3, 0.4, and 0.5 ml, which equal the target dosages of 5, 10, 15, 20, 30, 40, and 50 mg, were measured using syringes made by Shina and each sample was further diluted with 2 ml of $5\%$ dextrose. The solution of 100 mg/ml concentration was further diluted with $5\%$ dextrose to make a concentration of 20 mg/ml. Volumes of 0.25, 0.5, 0.75, 1.0, 1.5, 2.0, and 2.5 ml, which correspond to 5, 10, 15, 20, 30, 40, and 50 mg, were sampled by the same Shina's syringe as in single dilution method and then each sample was further diluted to make a total volume of 10 ml. Each sample was analyzed by HPLC. The measured dosages of each sample in both single and double dilution methods were lower than the target dosages; however, e values in double dilution method were higher than those in single dilution method for seven target dosages. Percent target dosages in single dilution method were 65 to $90\%$, while in double dilution method 91 to $94\%$. Statistically significant difference between two groups was shown in 5, 10, 15, 20, and 40 mg dosages (p<0.05). In conclusion, when preparing small vancomycin dosages lower an 20 mg $(volume{\leq}0.2\;ml)$, using Shina's syringes, the double dilution method has a closer value to the target dosage than single dilution method.

• 대한기계학회논문집B
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• 제27권9호
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• pp.1209-1219
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• 2003

The dynamic behaviors of the single vortex interacting with $CH_4-Air$ jet diffusion flame are investigated numerically. The numerical method is based on a predict-corrector scheme for a low Mach number flow. A two-step global reaction mechanism is adopted as a combustion model. Studies are conducted in fixed initial velocities for the three cases according as where $CO_2$ is added; (1) without dilution, (2) dilution in fuel stream and (3) dilution in oxidizer stream. A single vortex is generated by an axisymmetric jet, which is made by an impulse of a cold fuel when a flame is developed entirely in a computational domain. The simulation shows that $CO_2$ dilution in fuel stream results in somewhat larger vortex radius, and greater amount of entrainment of surrounding fluid than in other cases. Thus, the dilution of $CO_2$ in fuel stream enhances the mixing in single vortex and increases the stretching of the flame surface. The budgets of the vorticity transport equation are examined to reveal the mechanism of vortex formation when $CO_2$ is added. It is found that, in the case of $CO_2$ dilution in fuel stream, the vortex destruction due to volumetric expansion and the vortex production due to baroclinic torque are more dominant than in other cases.

• 대한미생물학회지
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• 제9권1호
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• pp.25-31
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• 1974

A comparative study was performed with 176 cultures of Salmonella organisms on tetracyline, neomycin and colistin in order to find out the relationship between the results obtained from the Ericsson's single disk method and the tube dilution method of antibiotic sensitivity tests which may be carried out in many hospital laboratories. With tetracycline, thirty-three out of 163 cultures of Salmonella typhi were found to be either sensitive or moderate sensitive by means of the disk method and thirty one(ca 94%) out of the thirty three cultures showed less than 1.0 ${\mu}g$ of the Minimal Inhibitory Concentretions(MIC) in the tube-dilution tests, which mean that there were a quite good agreement between the two methods. With neomycin, a hundred and five out of 163 S.typhi were appeared to be either sensitive or moderate sensitive by means of Ericsson's single disk method, among which 103 cultures showed less than 10.0 ${\mu}g$ MIC in the tubedilution method. And also there was a quite correlative pat. terns observed in the result of testing with 13 salmonella cultures other than S. typhi. With colistin, it was hard to observe any particular tendency in the distribution of plotting for 148 cultures showing less the 18 mm in the inhibiting zone diameters between MIC and disk sensitivity patterns except the fifteen, cultures out of 176 salmonella, which appeared to be sensitive in the single disk method and showed less than 1.0 ${\mu}g$ MIC in the tube dilution method.

• 한국해안해양공학회지
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• 제17권3호
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• pp.166-177
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• 2005

본 연구에서는 정체수역에서 유입이론과 일부 형상계수의 조정을 통해 근역에서의 하$\cdot$폐수 혼합거동을 해석할 수 있는 근역제트적분모형을 개발하기위해 총 6개의 상미분 보존방정식에 6개의 미지수를 가지는 문제를 수치적으로 풀기 위한 4차의 Runge-Kutta기법을 사용하였다. 또한, LIF 시스템을 이용하여 검정과정을 통해서 단일수평부력제트의 수리실험을 수행하였다. 그리고 기존의 모형 CORMIX 1, WSJET,그리고 본 모형의 계산결과를 수리실험결과와 서로 비교하였다. VISJET모형에 의해 예측된 중심선 제적이 운동량과 부력이 지배적인 구간에서는 실험결과와 근접한 반면에 본 제트적분모형에 의해 예측된 결과는 천이영역에서 측정된 궤적과 잘 일치하였다. 중심선희석률에 있어서 운동량과 부력이 지배적인 구간에서 CORMIX1 모형의 결과와 잘 일치하는 반면에 초기영역과 천이 영역에서 본 모형의 결과와 대체로 잘 일치하는 경향을 보였다.

• 대한수의학회지
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• 제45권4호
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• pp.569-574
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• 2005

Enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to reticuloendotheliosis virus (REV) at single serum dilution was standardized. REV HI, one of the Korean field isolates, was inoculated into chicken embryo fibroblast (CEF) cells and was harvested from the culture fluids and cells after 10 to 12 days. Viruses were purified by centrifugation at the $107,000{\times}g$ for 12 hours on 20, 30, 45% (W/V) sucrose gradient. Virus specific fraction was collected and used as ELISA antigen. To standardize ELISA, the optimal concentration of coating antigen ($1{\mu}g/well$) and conjugate (1/1000) was determined by corrected OD (OD value of positive serum-OD value of negative serum) and P/N ratio (OD value of positive serum/OD value of negative serum). To calculate ELISA titer by measuring absorbance at 1/400 single serum dilution, serum titrations were carried out for various sample sera together with standard positive and negative sera. The observed titers of serum samples were plotted against sample/positive (s/p) ratios at 1/400 serum dilution. From the above data, the ELISA titers could be calculated by the equation of $log_{10}$ ELISA titer = 2.2763 ($log_{10}$ s/p) + 3.482 (r = 0.93). For evaluating the sensitivity, the standardized method were compared with conventional agar gel immunodiffusion (AGID) test method using serum samples collected from REV infected field chicken flocks. Fifty seven of 60 samples (95%) were positive for REV by ELISA, whereas only 11 (18.3%) samples were positive by AGID test. This results suggested that the ELISA tests developed in this study could be used for detection of antibodies to REV with high sensitivity.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(역학)
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• pp.164-168
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• 1994

Single serologic tests may occasionally influence clinicians in making diagnoses. The antistreptolysin O (ASO) test is a frequently used tool for detecting recent Streptococcus pyogenes infection and is helpful in the diagnosis of diseases like rheumatic fever. Using data from a 1989 prospective study of 600 healthy male military recruits, in which 43% experienced S. pyogenes upper respiratory tract infection (2-dilution rise in ASO), this report compared two methods of interpreting a single ASO titer. Using the 'upper limit of normal' (80 percentile) method, recruits with an ASO titer of greater than 400 showed evidence of recent S. pyogenes infection. This method had a sensitivity and specificity of only 65.9 and 81.9% respectively. In contrast to the 'yes-no'. dichotomy of the 'upper limit of normal' method. the likelihood ratio method statistics were ASO value specific, more consistent with clinical judgment, and better emphasized the caution clinicians must use in interpreting a single ASO test.

• 한국미생물·생명공학회지
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• 제45권4호
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• pp.358-364
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• 2017

Asymmetric PCR preferentially amplifies one DNA strand for use in DNA hybridization studies. Linear-After-The-Exponential-PCR (LATE-PCR) is an advanced asymmetric PCR method which uses innovatively designed primers at different concentrations. This study aimed to optimise LATE-PCR parameters to produce single-stranded DNA of Candida spp. and Aspergillus spp. for detection via probe hybridisation. The internal transcribed spacer (ITS) region was used to design limiting primer and excess primer for LATE-PCR. Primer annealing and melting temperature, difference of melting temperature between limiting and excess primer and concentration of primers were optimized. In order to confirm the presence of single-stranded DNA, the LATE-PCR product was hybridised with digoxigenin labeled complementary oligonucleotide probe specific for each fungal genus and detected using anti-digoxigenin antibody by dot blotting. Important parameters that determine the production of single-stranded DNA in a LATE-PCR reaction are difference of melting temperature between the limiting and excess primer of at least $5^{\circ}C$ and primer concentration ratio of excess primer to limiting primer at 20:1. LATE-PCR products of Candida albicans, Candida parapsilosis, Candida tropicalis and Aspergillus terreus at up to 1:100 dilution and after 1 h hybridization time, successfully hybridised to respective oligonucleotide probes with no cross reactivity observed between each fungal genus probe and non-target products. For Aspergillus fumigatus, LATE-PCR products were detected at 1:10 dilution and after overnight hybridisation. These results indicate high detection sensitivity for single-stranded DNA produced by LATE-PCR. In conclusion, this advancement of PCR may be utilised to detect fungal pathogens which can aid the diagnosis of invasive fungal disease.

• 한국수산과학회지
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• 제11권1호
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• pp.19-24
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• 1978

장염비브리오균 검사에 있어서 검출방법에 따른 검출율은 차이를 알아보기 위하여 부산지방을 중심으로 해수 298개 시료, 112개 시료, 패류 169개 시료 어류 80개 시료 총 659개 시료를 단일 시험관을 사용하였을 때와 다수의 시험관을 사용하였을 때, 원시료 또는 일단계희석하였을 때의 검출율를 비교 실험한 자료를 분석 검토하여 그 결과를 요약하면 다음과 같다. 1. 해수에 있어서 10 ml를 접종 배양할 때에 장염비브리오균 음성인데도 같은 시료에서 1/100 는 1/1000로 희석한 시료에서 장염비브리오균 양성으로 나타나는 경우가 많았다. 이러한 현상은 이토, 패류, 어류에서도 같은 경향이었다. 2. 총 659개 시료 중에서 $52\%$에 해당하는 343개 시료가 장염비브리오균 양성으로 판정되었는데 이중희석하지 않은 시료에서 이 균이 검출된 것은 $22.5\%$인 149개 시료에 불과하였다. 시료별로 보면 해수는 $50\%$ 중 $24.5\%$, 이토의 경우는 $65.2\%$ 중 $28.6\%$, 패류에서는 $56.2\%$ 중 $22.5\%$에 불과하였다. 3. 최확수법에 의한 장염비브리오균 검출율은 단일희석법으로 측정했을 경우의 2배 이상이었다. 4. 3개 시험관을 사용한 최확수법에 있어서 제일 낮은 희석단계에서 양성으로 판정된 것은 $28.9\%$, 3개의 시험관 모두가 양성인 것은 $9.4\%$뿐이었다.

• 핵의학기술
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• 제16권2호
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• pp.3-6
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• 2012

방사성의약품 제조 후 품질관리의 중요성이 점점 커지고 있다. 품질관리 항목에는 물리적 성상, PH, 핵종의 순도 측정, 화학적 순도 측정, 방사화학적 순도 측정, 내독소 검사, 크립토픽스 잔류량 측정 등이 있다. 내독소 검사는 발열 및 쇼크등을 일으킬 수 있는 그람음성간균의 리포다당질이 포함된 검체가 인체에 주입되는 것을 방지하기 위한 검사법이다. FASTlab module을 이용하여 합성된 $^{18}F$-FDG의 내독소 검사 시행 시 간섭요인이 발생하여 제대로 된 검사가 시행되지 못하여 희석하는 방법을 이용하였다. LAL free water를 이용하여 비색법은 25 ${\mu}l$, 겔화법은 200 ${\mu}l$를 최소단위로 하여 희석배수가 10배수를 초과하지 않는 범위내에서 희석배수를 10배수, 20배수, 30배수, 40배수로 하여 희석하였다. 희석된 시약을 겔화법은 STT와 PCT에 각각 200 ${\mu}l$를 주입하고 Incubator에 $37^{\circ}C$로 1시간동안 배양하여 겔형성 정도를 확인하고, 비색법은 25 ${\mu}l$를 최소단위로 하여 위와 같이 희석한다. 희석된 시약은 ENDOSAFE-PTS의 Dilution factor를 입력하고 배수 당 하나의 카트리지를 4곳의 주입구에 25 ${\mu}l$씩 주입하고 결과 데이터를 확인한다. 결과는 겔화법은 FASTlab의 경우 40배수에서만 겔이 형성되었고, TRACERlab Mx의 경우 거의 모든 배수에서 겔이 형성되었지만 간헐적으로 형성되지 않는 경우도 있었다. 비색법은 FASTlab의 경우 40배수에서만 Spike Rxn time CV, Sample Rxn time CV, Spike recovery 모두 정상범위 안에 포함되었다. TRACERlab Mx의 경우 10배수에서 Spike Rxn time CV, Sample Rxn time CV, Spike recovery 모두 정상범위 안에 포함되었다. FASTlab에서 생산된 방사성의약품은 중화제인 $H_3PO_4$가 PCT내에 겔 형성에 관여하는 $Mg^{2+}$이온과 결합하여 겔 형성을 하지 못하는 것으로 추측된다. 이에 희석을 할 경우 $H_3PO_4$ 양이 줄어 간섭효과를 제거할 수 있었다. 엔도톡신 검사에서 간섭인자들은 무수히 존재한다. 이 간섭인자들은 합성장치나 시약에 따라 달라질 수 있으므로 이와 같은 간섭인자들을 극복하기 위한 노력으로 품질검사의 정확성과 신뢰를 제공하도록 해야 할 것이다.

• The Plant Pathology Journal
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• 제38권6호
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• pp.616-628
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• 2022

Resistance to pyraclostrobin due to a single nucleotide polymorphism at 143rd amino acid position on the cytochrome b gene has been a major source of concern in red pepper field infected by anthracnose in Korea. Therefore, this study investigated the response of 24 isolates of C. acutatum and C. gloeosporioides isolated from anthracnose infected red pepper fruits using agar dilution method and other molecular techniques such as cytochrome b gene sequencing, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and allele-specific polymerase chain reaction (PCR). The result showed that four isolates were resistant to pyraclostrobin on agar dilution method and possessed GCT (alanine) codon at 143rd amino acid position, whereas the sensitive isolates possessed GGT (glycine). Furthermore, this study illustrated the difference in the cytochrome b gene structure of C. acutatum and C. gloeosporioides. The use of cDNA in this study suggested that the primer Cacytb-P2 can amplify the cytochrome b gene of both C. acutatum and C. gloeosporioides despite the presence of various introns in the cytochrome b gene structure of C. gloeosporioides. The use of allele-specific PCR and PCR-RFLP provided clear difference between the resistant and sensitive isolates. The application of molecular technique in the evaluation of the resistance status of anthracnose pathogen in red pepper provided rapid, reliable, and accurate results that can be helpful in the early adoption of fungicide-resistant management strategies for the strobilurins in the field.