• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.147-154
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• 1997

국내에서 많이 사용되고 있는 제2세대 quinolone 항생제인 norfloxacin(NFX)에 대한 약역학적인 특성을 구명하기 위하여 국내에서 분리된 동물유래 병원성 세균에 대하여 시험관내에서 실험을 수행하여 다음과 같은 결과를 얻었다. 즉, E coli(n=89) 대한 NFX의 $MIC_{50}$와 $MIC_{90}$는 공히 0.02g/ml이었으며, Streptococcus spp.(n=36)에 대한 NFX의 $MIC_{50}$는 2g/ml 그리고 $MIC_{90}$는 4g/ml로 나타났다. Salmonella spp.(n=56)에 대한 NFX의 $MIC_{50}$와 $MIC_{90}$ 모두 0.2g/ml로 강한 항균력을 보였으며, Streptococcus spp.(n=24)에 대한 NFX의 $MIC_{50}$는 2g/ml 그리고 $MIC_{90}$가 4g/ml로 나타났다. Bacillus spp.(n=34)는 NFX의 $MIC_{50}$와 $MIC_{90}$는 모두 0.4g/ml으로서 대부분의 병원성 세균에 대해서 $MIC_{50}$와 $MIC_{90}$치가 동일하든지 또는 매우 비슷한 수치를 보여주었다. 그러나 NFX는 혐기성세균인 Clostridium spp.(n=34)에 대해서는 항균력이 매우 낮았다. 현재 수의임상에서 항균제 병용요법이 많이 응용되고 있는 것을 고려하여 NFX와 다른 항생물질간의 분획억제농도 (FICs)를 E coli 88ac을 시험균주로 하여 실험한 결과, NFX와 colistin과 병용할 때 FIC 값이 0.38로서 상승작용을 그리고 gentamicin, trimethoprim, amikacin, penicillin 및 tylosin과의 병용시 FIC 값이 각각 0.52, 0.56, 0.63, 1.00 및 1.02로서 상가작용을 보여주었으며, tetracyclin과의 병용시의 FIC값은 1.49로서 길항작용을 나타냄을 알 수 있었다. 한편 실제 항균제의 임상적용시 매우 주요한 요소인 항균활성후 저농도유효성(PAE)을 알아보기 위하여 E coli AB1157을 시험균주로 측정한 결과 PAE은 0.90~1.02 시간 그리고 S aureus R-209에 대해서는 PAE가 1.58~1.99 시간으로서 그람음성균 및 그람양성균 모두에 대해서 긴 PAE를 갖고 있음을 알 수 있었다.

• Journal of Environmental Health Sciences
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• v.30 no.1
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• pp.7-14
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• 2004

The change in filamentous bacteria appearance was observed by adjusting factors such as organic and nurient concentration of feed wastewater and the aeration rate in the reactor. In case that COD:N:P and DO were 100:10:1 and 6.1 m1/1 respectively, the mean SVI was 122 ml/g and the filaments were developed normally in flocs. For the low DO con- dition, however, the SVI averaged 186 ml/g and the appearance of outgrowing filaments were more frequent. When the high organic was supplied into the reactor, the average SVI was 274 ml/g and the distinct filamentous bulking was observed. Meanwhile when COD:N:P was maintained at 100: 1 :0.5, the SVI was as low as 87 ml/g and the appearance of filaments were minimal and the size of flocs was small comparing other experimental conditions. For normal, low aeration and high organic concentration, predominant filaments in the early stage of experiments were commonly Type 021N,S. natans which were usually found in low DO condition. However, Type 041, Type 1851, Type 0961 became predominant as experiments extended. Meanwhile, in low nutrient condition, Type 0675, Type 1851, and Type 0961 were observed. The filamentous bacteria appearance for SVI< 150(ml/g), Type 0041, Type 0961 (usually low organic in feed wastewater) were predominantly observed and SVI > 150(ml/g), S. natans and Type 021N(usually low DO in aeration basin) was predominant.

• Bulletin of the Korean Chemical Society
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• v.6 no.5
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• pp.291-295
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• 1985

The efficiency of photosensitization of methyl linoleate (ML) oxidation by N-acetyl-L-trypophan(NAT) and 3-methyl indole(scatole) was markedly enhanced by increased concentration of ML in ethanol solution. The fluorescence intensities of sensitizers were observed to be quenched by ML, indicating that ML interacts with the indole excited singlet state. The inhibition of photosensitization by azide demonstrated a possible role of singlet oxygen in the photosensitization. The steady state kinetic treatment of azide inhibition of photosensitization was expected to show linear increase of reciprocal yield of ML oxidation product vs. reciprocal ML concentration at constant azide concentration, but the actual slope was nonlinear. This indicates another competing reaction involved in the photosensitization, As a possible competing reaction, electron transfer from ML to the excited sensitizer was proposed, since the measured fluorescence quenching rate constant closely resembled electron transfer rate constant determined from ML concentration dependence of oxidation product formation.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.4
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• pp.435-441
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• 1998

We examined effects of interleukin $1{\alpha}$ ($IL1{\alpha}$) and phorbol 12, 13 dibutyrate (PDB), an activator of protein kinase C, on mRNA for Prostaglandin H synthase (PGHS) and prostanoid production in cultured ovine meningeal fibroblasts. Immuno- and morphologically-identified fibroblasts were derived from cerebral cortex and white matter from fetal lambs (approximately 120 days gestation) and grown to confluence on glass coverslips in 12 well plates. Levels of prostaglandin $F_{2{\alpha}}$ and the stable hydrolysis product of prostacyclin (i.e., $6-keto-PGF_{1{\alpha}}$) were determined using enzyme immunoassay. Relative amounts of mRNA were determined by in situ hybridization using ovine cDNA for PGHS1. $IL1{\alpha}$ (10 ng/ml) increased mRNA levels over baseline by $62{\pm}19%$ (p＜0.05) at 60 min., $37{\pm}12%$ (NS) at 120 min., and $36{\pm}18%$ (NS) at 240 min (n=12). Levels of $6-keto-PGF_{1{\alpha}}$ were $148{\pm}18%$ pg/ml during baseline, $246{\pm}41%$ pg/ml at 60 min., $248{\pm}40%$ pg/ml at 120 min., and $259{\pm}62%$ pg/ml at 240 min (all p＜0.05) (n=12). $PGF_{2{\alpha}}$ was increased although it wasn't statistically significant. However, $IL1{\alpha}$ decreased $PGE_2$ level significantly (all p＜0.05). PDB $(10^{-6}M)$ increased mRNA levels over baseline by $25{\pm}6%$ after 30 min., $40{\pm}6%$ after 60 min., and $20{\pm}8%$ after 90 min. (n=9) (all p＜0.05). Levels of $6-keto-PGF_{1{\alpha}}$ were $200{\pm}43%$ pg/ml during baseline, $202{\pm}43%$ pg/ml after 30 min. (NS), $268{\pm}58%$ pg/ml after 60 min. (p＜0.05), and $296{\pm}60%$ pg/ml after 90 min. (p＜0.05) (n=9). Levels of $PGF_{2{\alpha}}$ were $178{\pm}26%$ pg/ml during baseline, $300{\pm}30%$ pg/ml after 30 min., $299{\pm}35%$ pg/ml after 60 min., and $355{\pm}32%$ pg/ml after 90 min (all p＜0.05) (n=6). Actinomycin-D (1 mg/ml) prevented increases in mRNA, $6-keto-PGF_{1{\alpha}}$, and $PGF_{2{\alpha}}$ at 60 min. for both $IL1{\alpha}$ and PDB. We conclude that cerebral fibroblasts are avid producers of prostanoids, and that enhanced production of PGHS is responsible for augmented $PGF_{2{\alpha}}$ and prostacyclin production in the presence of an activator of protein kinase C and for decreased $PGE_2$ and increased prostacyclin production in the presence of $IL1{\alpha}$.

• Journal of the Korean Chemical Society
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• v.62 no.2
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• pp.113-117
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• 2018

The basic hydrogel lens with addition of N,N-dimethylacrylamide (DMA) and N-methyl-N-vinylacetamide (NMV) were manufactured. The optical and physical characteristics of ophthalmic lens were evaluated by measuring water content, oxygen permeability (Dk), refractive index and optical transmittance. The water content & oxygen permeability (Dk) of sample containing Ref., DMA group and NMV group was in the average of 34.48%, 35.54~49.19% & $13.003{\sim}18.468{\times}10^{-11}(cm^2/sec)$($mlO_2/ml{\times}mmHg$) and 36.28~44.95% & $12.270{\sim}16.883{\times}10^{-11}(cm^2/sec)$ ($mlO_2/ml{\times}mmHg$), respectively. And also, refractive index of the sample containing Ref., DMA group and NMV group was in the average of 1.4350, 1.4330~1.4131 and 1.4335~1.4195, respectively. Standard hydrogel monomer containing DMA and NMV was expected to be used usefully as a material for fabricating hydrophilic functional ophthalmic lens.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.738-742
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• 2003

The monitoring was carried out for one year on 20 farms of Mediterranean buffalo situated in central Italy. The milk yield, the somatic cell count, the coagulating properties and some components were determined. The average value of somatic cells was $21.28n{\times}10^3/ml$. Milk production decreased when somatic cell numbers increased. The rennet clotting time increased significantly when somatic cells were higher than $300.00n{\times}10^3/ml$, the curd firming time was significantly higher when somatic cells were more than $1,000.00n{\times}10^3/ml$ and the curd firmness increased up to $200.00n{\times}10^3$/ml, then gradually decreased. Protein and casein decreased when somatic cells increased and the same trend was shown by casein/protein ratio. Both for these components and the coagulating properties the threshold limit of somatic cells to obtain better results was $200.00n{\times}10^3/ml$. The somatic cell number did not show a trend which was strictly influenced by the lactation stage, contrary to what happened in the other species.

• Korean Journal of Veterinary Research
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• v.39 no.5
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• pp.1021-1027
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• 1999

This study was carried out to determine the effects of ${\beta}-carotene$ on the control of mastitis in dairy cows during the dry period. The relationship between the levels of plasma ${\beta}-carotene$ and the status of udder health in Holstein dairy cows were investigated. Blood samples were collected from 117 cows to compare the levels of plasma ${\beta}-carotene$ in lactating cows. The levels of plasma ${\beta}-carotene$ were $1.82{\mu}g/ml$ in healthy cows(n = 65) and $1.12{\mu}g/ml$ in mastitic cows(n = 52), respectively(p < 0.01). In the experiment to compare the level of plasma ${\beta}-carotene$ in the cows at different stages of lactation, the plasma ${\beta}-carotene$ levels were $1.73{\mu}g/ml$ in lactating cows(n = 22), $1.29{\mu}g/ml$ in nonlactating cows(n = 35) and $0.43{\mu}g/ml$ in cows after calving(n = 16)(p < 0.05).

• Korean Journal of Clinical Pharmacy
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• v.34 no.2
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• pp.134-139
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• 2024

Background: Increasing numbers of studies and research about artificial intelligence (AI) and machine learning (ML) have led to their application in clinical trials. The purpose of this study is to analyze computer-based new technologies (AI/ML) applied on clinical trials registered on ClinicalTrials.gov to elucidate current usage of these technologies. Methods: As of March 1st, 2023, protocols listed on ClinicalTrials.gov that claimed to use AI/ML and included at least one of the following interventions-Drug, Biological, Dietary Supplement, or Combination Product-were selected. The selected protocols were classified according to their context of use: 1) drug discovery; 2) toxicity prediction; 3) enrichment; 4) risk stratification/management; 5) dose selection/optimization; 6) adherence; 7) synthetic control; 8) endpoint assessment; 9) postmarketing surveillance; and 10) drug selection. Results: The applications of AI/ML were explored in 131 clinical trial protocols. The areas where AI/ML was most frequently utilized in clinical trials included endpoint assessment (n=80), followed by dose selection/optimization (n=15), risk stratification/management (n=13), drug discovery (n=4), adherence (n=4), drug selection (n=1) and enrichment (n=1). Conclusion: The most frequent application of AI/ML in clinical trials is in the fields of endpoint assessment, where the utilization is primarily focuses on the diagnosis of disease by imaging or video analyses. The number of clinical trials using artificial intelligence will increase as the technology continues to develop rapidly, making it necessary for regulatory associates to establish proper regulations for these clinical trials.

• Journal of Nutrition and Health
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• v.36 no.8
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• pp.841-850
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• 2003

Soy-based formula has been used for centuries in Korea. Soybeans contain phytochemicals with a biochemically active component, isoflavone. Isoflavone is a kind of phytoestrogens, structurally and functionally similar to estrogen. This study was conducted to investigate the effects of soy-based infant formula on growth, development, and isoflavone concentration in the plasma and urine. Thirty-nine healthy infants who were delivered at K university medical center were recruited. Experimental groups were the breast milk group (n = 15, BM) who were fed breast milk, soy-based formula group (n = 10, SBF) who were fed soy-based infant formula, and the casein-based formula group (n = 14, CBF) who were fed casein-based infant formula for 4 months. HPLC analysis was used to measure the concentration of isoflavones. The measurements of infant weight, length, head circumference and chest circumference were all in the normal growth range and were similar among the experimental groups. No significant differences were found in the scores of total mean of infant development test (Development Quotient, DQ) among the experimental groups. The isoflavone content of soy-based formula was significantly higher than. that of breast milk and casein-based formula. Plasma concentration of daidzein and genistein in the infants fed soy-based formula (daidzein : 264.1 ng/ml, genistein : 392.1 ng/ml) was significantly higher (p<.0001) than that in infants fed breast milk (daidzein : 3.4 ng/ml, genistein : 3.8 ng/ml) and casein-based formula (daidzein: 8.1 ng/ml, genistein: 9.3 ng/ml). Also, urinary daidzein and genistein concentrations in infants fed soy-based formula (daidzein: 19.82 $\mu$g/ml, genistein : 17.89 $\mu$g/ml) were significantly higher (p<.001) than those in infants fed breast milk (daidzein: 0.28 $\mu$g/ml, genistein : 0.22 $\mu$g/ml) and casein-based formula (daidzein : 0.45 $\mu$g/ml, genistein : 0.33 $\mu$g/ml).

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.4
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• pp.416-421
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• 1998

The objective of this study was to investigate the responsiveness of hypophysis and gonads to synthetic GnRH among noncycling Murrah buffalo heifers at 24 months of age. The plasma FSH, LH, estradiol and progesterone levels were measured in blood samples collected at 1 hour before and upto 18th day subsequent to the administration of GnRH ($(200 {\mu}g)$) or saline (2 ml). The pretreatment levels of plasma FSH, LH estradiol and progesterone among GnRH treated heifers (N = 6) were $11.55{\pm}0.57ng/ml$, $0.68{\pm}0.06ng/ml$, $19.84{\pm}0.82pg/ml$ and $0.45{\pm}0.07ng/ml$ respectively. A quick elevation of FSH (p < 0.01) and LH (p < 0.05) within 5 min of GnRH administration was observed in all the heifers. The peak FSH ($74.97{\pm}18.63ng/ml$) and LH ($3.09{\pm}0.54ng/ml$) level was obtained at 30 min of GnRH administration. The elevated level of plasma estradiol on 5th to 18th day, FSH on 7th to 9th day (n = 3) and the progesterone on 13th to 18th day (n = 2) of GnRH injection was obtained. The study indicates that gonads of buffalo heifers at 24 months of age are responsive of GnRH induced gonadotropin release for folliculogenesis and luteal tissue formation