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Antibiotics Susceptability of Streptococcus pneumoniae Isolated from Pharynx in Healthy Korean Children and Choice of Proper Empirical Oral Antibiotics Using Pharmacokinetics/Pharmacodynamics Model (국내의 소아에서 분리된 폐구균의 항생제 감수성 양상 및 약력동학 모델을 이용한 적절한 항생제의 선택)

  • Paik, Ji Yeun;Choi, Jae Hong;Cho, Eun Young;Oh, Chi Eun;Lee, Jina;Choi, Eun Hwa;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.18 no.2
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    • pp.109-116
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    • 2011
  • Purpose : Pneumococcus is one of the most important causes of invasive infection through the childhood period. In January 2008, the Clinical and Laboratory Standards Institute (CLSI) published revised penicillin breakpoints for Streptococcus pneumoniae and penicillin susceptibility rates of S. pneumoniae increased in Korea. This study was performed to determine the probability of oral amoxicillin for the empirical treatment achieving bactericidal exposure against pneumococcus using pharmacodynamics model. Methods : Twenty-three isolates of pneumococci were subjected to determine minimum inhibitory concentration (MIC) for ${\beta}$-lactams and macrolide. For the ${\beta}$-lactams, exposure of fT >MIC (time that free drug concentrations remain above the MIC) for 50% of the administration interval have determined the probability of target attainment (PTA), and regimens that had a PTA >90% were considered optimal. An analysis was performed by applying MIC of 23 isolates to a 5000-patient Monte Carlo simulation model. Results : Among 23 isolates from healthy children, 7 (30.4%) isolates were MIC ${\leq}$1.0 ${\mu}g$/mL and 19 (82.6%) were MIC ${\leq}$2 ${\mu}g$/mL for amoxicillin. Amoxicillin 40 mg/kg/day achieved PTA >90% at MIC ${\leq}$1.0 ${\mu}g$/mL but PTA decreased to 52% at MIC 2 ${\mu}g$/mL, whereas amoxicillin 90 mg/kg/day can predict 97% of PTA at MIC 2 ${\mu}g$/mL. Overall, oral amoxicillin 90 mg/ kg/day for the empirical treatment against pneumococcus can expect more successful response in Korean children. Conclusion : Considering the resistantce pattern of pneumococci in Korean children, we estimate that oral amoxicillin 90 mg/kg/day will provide a pharmacodynamic advantage for the empirical treatment against pneumococcus. And low dose amoxicillin or macrolide are expected to have higher chance of treatment failure than high dose oral amoxicillin.

Impacts of Green Manure Crop and Charcoal Applications on Ginger Growth and Soil Properties (녹비작물 및 Charcoal 처리가 생강 생육 및 토양 특성에 미치는 영향)

  • Yang, Hong-Seok;Kim, Dong-Jin;Ahn, Byung-Koo;Lee, Jin-Ho
    • Korean Journal of Organic Agriculture
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    • v.22 no.3
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    • pp.503-519
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    • 2014
  • This study was conducted to investigate ginger growth and its nutrient uptake depending on changes of soil properties as affected by applications of green manure crop and/or charcoal in continuous cropping system. The green manure crops applied were barley and hairy vetch, and charcoal was additionally treated in selected plots as a soil conditioner. Experimental plots were prepared as Plot 1 (control), Plot 2 (barley of 8kg $10a^{-1}$), Plot 3 (hairy vetch of 12kg $10a^{-1}$), Plot 4 (charcoal of 1,000kg $10a^{-1}$ and barley 8kg $10a^{-1}$), and Plot 5 (charcoal of 1,000kg $10a^{-1}$ and hairy vetch of 12kg $10a^{-1}$) with two different soil conditions (high clay content, HCC and low clay content, LCC). When comparing selected chemical properties of soils before and after cultivating ginger plant, soil pH decreased from 6.9~8.1 to 6.8~7.6, and electrical conductivity (EC) also declined from $0.45{\sim}1.25dSm^{-1}$ to $0.30{\sim}0.61dSm^{-1}$. However, the content of soil organic matter (SOM) and total nitrogen (T-N) increased. Thus, the soil chemical properties were improved with the applications of green manures and charcoal. Also, macro- and micro-nutrient contents of ginger plants in the different plots were various between normal and diseased plants grown in soils with HCC and LCC. In particular, the concentration of manganese (Mn) was 3~4 folds higher in the diseased plant than in the normal plants. Ginger growth status and yield was relatively improved with the applications of green manures and charcoal as comparing with control plot. Especially in the Plot 4 with LCC, the ginger plant was not infected by root-rot disease.

Macrozoobenthic Community Structures in the Shallow Subtidal Soft-bottoms around Wando-Doam Bay during Summer Season (남해 완도-도암만 연성기질의 여름철 대형저서동물의 군집구조)

  • LIM, HYUN-SIG;CHOI, JIN-WOO;SON, MIN-HO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.23 no.2
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    • pp.91-108
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    • 2018
  • An ecological study on subtidal macrobenthic fauna was conducted from 25 stations in the estuarine area of Wando-Doam Bay, southern coast of Korea during August 2013. A total of 186 species was collected with a mean density of $1,229ind./m^2$ and a mean biomass of $265.7g/m^2$. Polychaetes showed the richest benthic fauna comprising 43% of total fauna, whereas mollusks appeared as density- and biomass-dominant fauna accounted for 45% and 48% of the mean density and biomass, respectively. The number of species and mean faunal density were relatively higher at the stations surrounded by Sinjido, Joyakdo and Gogeumdo showing a gradual decrease toward inner bay stations. Species number and density were negatively correlated with bottom water temperature, but they were positively correlated with both the bottom salinity and DO. The most dominant species in terms of density was a semelid bivalve, Theora fragilis which showed a positive correlation with TOC content of surface sediment and its high density occurred around Gogeum-Sinji-Joyakdo area where dense aquaculture facilities exist. In the bay mouth area, an amphipod species, Eriopisella sechellensis showed its higher density at the stations with low organic content but fine grains. The combination of water temperature, salinity, pH of bottom water, water and sulfur content of the surface sediment could explain 71% of the spatial distribution of macrobenthic fauna from the Bio-Env analysis. From the cluster analysis, the study area consisted of 6 distinct station groups lineated from offshore area toward inner area. Ampharete arctica, Goniada maculata, Eriopisella sechellensis, Theora fragilis, Caprella sp. were identified as the main contributing faunas in classification by the SIMPER analysis. From the value of BPI, the benthic communities at the inner and central Wando-Doam Bay were assessed to be in a normal condition whereas those at the outer Wando harbor and Gogeum-Sinji-Joyakdo area were assessed in a poor or very poor condition due to the high concentration of particulate organic matter might be originated from the nearby dense aquaculture facilities. This study indicated that pristine inner bay has been influenced by the organic material supplied from the outer bay. Thus it is necessary to establish an ecological management plan to reduce organic enrichment of sediment from dense aquaculture facilities in the outer bay.

Feasibility Study of Wetland-pond Systems for Water Quality Improvement and Agricultural Reuse (습지-연못 연계시스템에 의한 수질개선과 농업적 재이용 타당성 분석)

  • Jang, Jae-Ho;Jung, Kwang-Wook;Ham, Jong-Hwa;Yoon, Chun-Gyeong
    • Korean Journal of Ecology and Environment
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    • v.37 no.3 s.108
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    • pp.344-354
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    • 2004
  • A pilot study was performed from September 2000 to April 2004 to examine the feasibility of the wetland-pond system for the agricultural reuse of reclaimed water. The wetland system was a subsurface flow type, with a hydraulic residence time of 3.5 days, and the subsequent pond was 8 $m^3$ in volume (2 m ${\times}$ 2 m ${\times}$ 2 m) and operated with intermittent-discharge and continuous flow types. The wetland system was effective in treating the sewage; median removal efficiencies of $BOD_5$ and TSS were above 70.0%, with mean effluent concentrations of 27.1 and 16.8 mg $L^{-1}$, respectively, for these constituents. However, they did often exceed the effluent water quality standards of 20 mg $L^{-1}$. Removal of T-N and T-P was relatively less effective and mean effluent concentrations were approximately 103.2 and 7.2 mg $L^{-1}$, respectively. The wetland system demonstrated high removal rate (92 ${\sim}$ 90%) of microorganisms, but effluent concentrations were in the range of 300 ${\sim}$ 16,000 MPN 100 $mL^{-1}$ which is still high for agricultural reuse. The subsequent pond system provided further treatment of the wetland effluent, and especially additional microorganisms removal in addition to wetland-pond system could reduce the mean concentration to 1,000 MPN 100 $mL^{-1}$ from about $10^5$ MPN 100 $mL^{-1}$ of wetland influent. Other parameters in the pond system showed seasonal variation, and the upper layer of the pond water column became remarkably clear immediately after ice melt. Overall, the wetland system was found to be adequate for treating sewage with stable removal efficiency, and the subsequent pond was effective for further polishing. This study concerned agricultural reuse of reclaimed water using natural systems. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, wetland- pond system was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water in rural area.

Effects of Sprinkler and Fan Cooling System in Loose Barn on the Physiological Parameter and Milk Productivity in Holstein Cows During Summer (개방식우사내 Fan과 Sprinkler설치가 착유우의 생리적 변화 및 유생산성에 미치는 영향)

  • 정태영;이현민;김종민;김동일;이연섭;이인형
    • Journal of Animal Environmental Science
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    • v.2 no.1
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    • pp.41-52
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    • 1996
  • This experiment was carried out to study the effect of sprinkler and fan cooling system on the physiological parameter, milk production and milk composition for Holstein cows in hot, humid climates. Thirty cows were assigned to one of two sections of open-sided loose barn. Water nozzles of sprinkler system were spaced in line at 1.2m intervals. Forced air was provided by 85cm diameter fans at rate of 3.4㎥/sec. The results obtained from these experiments are as follows: 1. There was no significant difference in meteorological data between control and fan + sprinkler cooling system(treatment group). 2. Skin temperature and rectal temperature of the treatment group were significantly lower than those of the control group (32.96 : 39.53$^{\circ}C$ vs 34.02 : 41.21$^{\circ}C$ respectively) (P<0.05). 3. Serum cortisol concentration of the treatment group(0.90$\mu\textrm{g}$/dL) was lower than that of control group(1.44$\mu\textrm{g}$/dL)(P<0.05). 4. Milk production of cows cooled with a sprinkler and fan cooling system was significantly higher than that of no cooling system (P<0.0l). 5. Lactose, protein and solid-not-fat content of milk were not changed by the treatments. Milk fat content of the control(3.23%) was low compared with the treatment group(3.38%). Somatic cell count was reduced by 26.63% in the treatment. The results indicate that a sprinkler and fan cooling systems can provide an effective means to relieve heat stress and enhance productivity of lactating Holstein cows during hot and humid summer season.

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Quality Characteristics and Granule Manufacture of Mulberry and Blueberry Fruit Extracts (오디 및 블루베리 추출물을 이용한 과립제조 및 품질특성)

  • Park, Hye-Mi;Yang, Su-Jin;Kang, Eun-Ji;Lee, Dae-Hoon;Kim, Dae-Ik;Hong, Joo-Heon
    • Korean journal of food and cookery science
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    • v.28 no.4
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    • pp.375-382
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    • 2012
  • The quality characteristics of granules prepared from water and 50% ethanol extracts of mulberry and blueberry were investigated. The total polyphenol and total flavonoid contents of mulberry and blueberry were higher in the 50% ethanol extract than those in the water extract. Total anthocyanin content was highest in the 50% mulberry ethanol extract (470.91 mg/100 g). Oxygen radical absorbance capacity (ORAC) of the mulberry and blueberry extracts was 335.37 ${\mu}moles\;TE/g$ and 238.14 ${\mu}moles\;TE/g$, respectively. Superoxide radical scavenging activity of the mulberry and blueberry extracts increased with an increase in extract concentration. Total polyphenol and flavonoid contents of granules from the mulberry extract were 4.83 mg/mL and 3.49 mg/mL, respectively. Total anthocyanin content of granules from the mulberry and blueberry extracts was 76.26 mg/100 g and 75.26 mg/100 g, respectively. Electron donating ability and ORAC of granules from the mulberry and blueberry extracts were 45.09% and 24.10%, 87.65 ${\mu}moles\;TE/g$ and 57.59 ${\mu}moles\;TE/g$, respectively. Granules that were stored for 7 weeks at room temperature had low anthocyanin content degradation and Hunter color values (L, a, and b).

The Effects of Salt and NaNO2 on Fatty Acid Composition, Free Amino Acids, Microbial Counts and Sensory Characteristics of Dry-cured Ham Processed under Korean Environment (소금과 아질산염 처리수준이 자연숙성 건염햄의 지방산 조성, 유리아미노산, 미생물수 및 관능적 특성에 미치는 영향)

  • Seong, Pil-Nam;Kim, Jin-Hyoung;Cho, Soo-Hyun;Kang, Dong-Woo;Kang, Geun-Ho;Park, Beom-Young;Lee, Jong-Moon;Jung, Jae-Hong;Kim, Dong-Hoon
    • Food Science of Animal Resources
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    • v.30 no.3
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    • pp.435-442
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    • 2010
  • The study analyzed the effects of salt concentration [high salt (HS) and low salt (LS)] and sodium nitrite ($NaNO_2$), which are typically utilized in Korean processing facilities, on fatty acid composition, free amino acids, microbial counts and sensory characteristics of processed dry-cured ham. Four different treatments were considered: three hams (11.30 kg) salted with 92 g/kg salt (w/w) (HS), three hams (10.65 kg) treated with HS and 100 ppm $NaNO_2$ (HS+$NaNO_2$), three hams (11.42 kg) salted with 62 g/kg salt (w/w) (LS), and three hams (10.62 kg) treated with LS and 100 ppm $NaNO_2$ (LS+$NaNO_2$). Fatty acid composition analysis revealed significantly (p<0.05) higher saturated fatty acid and lower (p<0.05) unsaturated fatty acid in the HS+$NaNO_2$ group compared with the other groups. Glutamate, alanine and lysine free amino acids were higher than the other free amino acids. The processing conditions did not significantly affect the free amino acids of biceps femoris muscles, except for the proline content (p>0.05). In sensory evaluation, the fermentation aroma of the LS group was higher than that of the HS group. The aerobic counts consistently ranged from from $2.3{\times}10^2$ to $1.11{\times}10^4$ CFU/g. Escherichia coli including strain O157:H7, Staphylococcus aureus, and Salmonella spp. were not detected.

FINITE ELEMENT ANALYSIS OF MAXILLARY CENTRAL INCISORS RESTORED WITH VARIOUS POST-AND-CORE APPLICATIONS (여러가지 post-and-core로 수복된 상악 중절치의 유한요소법적 연구)

  • Seo, Min-Seock;Shon, Won-Jun;Lee, Woo-Cheol;Yoo, Hyun-Mi;Cho, Byeong-Hoon;Baek, Seung-Ho
    • Restorative Dentistry and Endodontics
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    • v.34 no.4
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    • pp.324-332
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    • 2009
  • The purpose of this study was to investigate the effect of rigidity of post core systems on stress distribution by the theoretical technique, finite element stress-analysis method. Three-dimensional finite element models simulating an endodontically treated maxillary central incisor restored with a zirconia ceramic crown were prepared and 1.5 mm ferrule height was provided. Each model contained cortical bone, trabecular bone, periodontal ligament, 4 mm apical root canal filling, and post-and-core. Six combinations of three parallel type post (zirconia ceramic, glass fiber, and stainless steel) and two core (Paracore and Tetric ceram) materials were evaluated, respectively. A 50 N static occlusal load was applied to the palatal surface of the crown with a $60^{\circ}$angle to the long axis of the tooth. The differences in stress transfer characteristics of the models were analyzed. von Mises stresses were chosen for presentation of results and maximum displacement and hydrostatic pressure were also calculated. An increase of the elastic modulus of the post material increased the stress, but shifted the maximum stress location from the dentin surface to the post material. Buccal side of cervical region (junction of core and crown) of the glass fiber post restored tooth was subjected to the highest stress concentration. Maximum von Mises stress in the remaining radicular tooth structure for low elastic modulus resin core (29.21 MPa) was slightly higher than that for high elastic modulus resin core (29.14 MPa) in case of glass fiber post. Maximum displacement of glass fiber post restored tooth was higher than that of zirconia ceramic or stainless steel post restored tooth.

Changes in Serum Lipid Components and Blood Glucose by Krill (Euphausia superba) Meal and NaF in Rats (크릴 분말 및 NaF 첨가 식이가 흰쥐의 혈청 지질성분 및 혈당 변동에 미치는 영향)

  • Jin, Dong-Hyeok;Oh, Da-Young;Lee, Young-Geun;Kang, Dong-Soo;Kim, Han-Soo
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.4
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    • pp.938-946
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    • 2017
  • This study was conducted to examine the changes in serum lipid components and blood glucose by krill (Euphausia superba) meal and sodium fluoride (NaF) in rats fed on experimental diets and administered orally to NaF 10 mg for 5 weeks. Body weight of rats decreased as the amount of krill meal diet increased, it was observed the basal diet plus NaF group (BF group) compared to the lower basal diet group (BD group). The serum concentrations of total cholesterol, LDL (low-density lipoprotein) cholesterol, free cholesterol, triglyceride (TG), phospholipid (PL) and blood glucose in serum were higher in the BF group than the 10% krill meal group plus NaF 10 mg (KF10 group) or BD group, the 20% krill meal plus NaF 10 mg group (KF20 group), the 30% krill meal plus NaF 10 mg group (KF30 group). Conversely depending on the content of krill meal for the HDL (high-density lipoprotein) cholesterol level, it showed higher results. The concentration of total protein was no significant difference among the groups (p<0.05). The results indicate that a krill meal diet effectively inhibited increases in lipid elevation and blood glucose level in the sera of rats.

In Vitro Assay on Biological Characteristics of Different Extracts from Acorus calamus L. var angustatus (창포(Acorus calamus L. var angustatus) 추출물의 생리활성 검정)

  • Heo, Buk Gu;Park, Yong Seo;Yoo, Yong Kweon;Han, Tae Ho;Park, Yun Jum;Sin, Jang Sik;Cho, Ja Yong
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.3
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    • pp.168-173
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    • 2008
  • This study was conducted to determine biological characteristics of Acorus calamus L. angustatus by using aqueous, ethanol and methanol extracts from the leaves and the rhizomes of Acorus calamus L. angustatus plants. The highest total phenol contents were found in the extracts from the leaves of Acorus calamus L. angustatus ($68.4mg{\cdot}L^{-1}$) followed by rhizome ($49.3mg{\cdot}L^{-1}$). At $1,000mg{\cdot}L^{-1}$ the free radical scavenging activity of 1, 1-Diphenyl-2-picrylhydrazyl showed the highest activity in the extracts of the leaves and the rhizomes by 86.3% and 86.1%, respectively. Total flavonoid contents at $2,000mg{\cdot}L^{-1}$ extracts showed the greatest amount in the aqueous leaf extracts ($61.1mg{\cdot}L^{-1}$), and the ethanol rhizome extracts ($15.4mg{\cdot}L^{-1}$). Nitrite radical scavenging activity at $2,000mg{\cdot}L^{-1}$ was highest in the methanol extracts from leaves and rhizomes by 75.7% and 77.9%, respectively. Mushroom tyrosinase inhibition activity of leaves and rhizome from the Acorus calamus L. angustatus was very low, showing less than 1.3% regardless of the extract solvent, plant part, and concentration. These results indicated that methanol extracts from leaves exhibited higher biological activities than other extracts from rhizomes.