• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.119-119
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• 1997

Valacyclovir is a L-valyl ester prodrug of acyclovir which is a highly effective and selective antiviral agent in the treatment of herpes virus diseases. Valacyclovir is rapidly and almost completely converted to acyclovir and increases the oral bioavailability of acyclovir three to five fold. However, the intestinal absorption mechanism of valacyclovir is not clear. If the improved absorption mechanism of valacyclovir is fully understood, it will provide a rationale of designing the amino acid ester prodrugs of polar drugs containing hydroxyl group. The main objective of our present study is to characterize the membrane transport mechanism of valacyclovir. Methods : Intestinal absorption of valacyclovir was investigated by using in-situ rat perfusion study and its wall permeability was estimated by modified boundary layer model. The membrane transport mechanism was also investigated through the uptake study in Caco-2 cells and in CHO-hPepTl cells. Results : In the rat perfusion study, the wall permeability of valacyclovir was ten times higher than acyclovir and showed concentration dependency, Valacyclovir also demonstrated a D,L stereo-selectivity with L-isomer having an approximately five-fold higher permeability than D-isomer. Mixed dipeptides and cephalexin, which are transported by dipeptide carriers, strongly competed with valacyclovir for the intestinal absorption, while L-valine did not show any competition with valacyclovir. This indicated that the intestinal absorption of valacyclovir could be dipeptide carrier-mediated. In addition, the competitive uptake study in Caco-2 cells presented that dipeptides reduced the valacyclovir uptake but valine did not. Also, in IC$\sub$50/ study, valacyclovir showed strong inhibition on the $^3$H-gly-sar uptake in CHO-hPepTl cells over-expressing a human intestinal peptide transporter. Taken together, the result from our present study indicated that valacyclovir utilized the peptide transporter for the intestinal absorption.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1341-1350
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• 2007

This study was designed to ultimately develop a highly efficient mass production technology of bacterial cellulose isolated from the citrus gel fermented by G. hansenii TL-2C. Pilot equipment made with FRP vessel length (665 mm) ${\times}$ width (375 mm) ${\times}$ height (210 mm) was developed for mass production of the citrus gel. To develop the optimal conditions for mass production of citrus gel, comprised of citrus juice (6,000 mL) diluted 100 times, containing 5% seed bacteria, 10% sucrose, and 1% ethanol, citrus juice was fermented at $30^{\circ}C$ for 14 days, and gel productivity in pilot system was examined. BC was isolated and purified from the citrus gel, and their chemical composition and physicochemical properties were investigated.

• Tuberculosis and Respiratory Diseases
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• v.38 no.1
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• pp.16-24
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• 1991

Adenosine deaminase (ADA) is an enzyme which is essential for the differentiation of lymphoid cells, especially T-cells and ADA plays a role in the maturation of monocyte to macrophage. Therefore ADA levels are related to stimulation of cellular immunity. We have investigated the measurement of ADA activity in bronchoalveolar lavage fluid of the patients with active and inactive pulmonary tuberculosis and control group. The results obtained are as follows: 1) The ADA activity and corrected ADA activity from the BAL fluid in active tuberculosis group (Total Lavage ADA; $18.4{\pm}22.5\;mU$, Total Lavage ADA/Albumin; $2.45{\pm}1.61\;mU/mg$) were increased when compared with those in inactive tuberculosis (TL-ADA; $5.8{\pm}2.5\;mU$, TL-ADA/Alb; $1.83{\pm}O.53\;mU/mg$) and control (TL-ADA; $6.6{\pm}4.3\;mU$, TL-ADA/Alb; $1.62{\pm}0.60\;mU/mg$) groups. 2) The ADA activity and lavage ADA/serum ADA activity ratio in BAL fluid from the lesion site (TL-ADA; $42.9{\pm}42.3\;mU$, L-ADA/S-ADA; $0.53{\pm}0.32$) were increased when compared with those from the non-lesion site (TL-ADA; $12.5{\pm}11.2\;mU$, L-ADA/S-ADA; $0.29{\pm}0.12$)and normal side (TL-ADA; $12.7{\pm}11.0\;mU$, L-ADA/S-ADA; $0.34{\pm}0.27$) in active tuberculosis group. 3) The ADA activity in BAL fluid from far advanced group (TL-ADA; $62.5{\pm}30.3\;mU$) was increased when compared with those from the mild group (TL-ADA; $10.5{\pm}7.5\;mU$) and moderate advanced group (TL-ADA; $13.2{\pm}11.7\;mU$) in active tuberculosis. 4) The albumin level from the BAL fluid was correlated with the ADA activity (R=0.89). 5) The ADA activity recovered from the BAL fluid was correlated with the recovered lymphocyte percentage (R=0.60). In conclusion, the ADA activity from the BAL fluid in active tuberculosis group was increased when compared with that in inactive tuberculosis and control groups, especially from the lesion site. To evaluated the specificity of ADA determination for diagnosis of active tuberculosis, BAL must be done at lesion site of the diseased lung and the proper correcting material other than albumin must be chosen to correct the dilution factor of lavage fluid.

• The Journal of the Acoustical Society of Korea
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• v.38 no.4
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• pp.396-405
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• 2019

The speech privacy of closed office rooms located in a university campus was measured and assessed in terms of SPC (Speech Privacy Class) values. The measurements of two quantities, the LD (Level Difference) between a source and a receiving room, and the background noise level ($L_b$) at the receiving room were carried out in 5 rooms located in 3 different buildings in the university campus. Each of the 5 rooms was adjacent to both offices and corridors through walls. The TL (Transmission Loss) between the source and the receiver room was also measured to compare the difference of two standard methods, ASTM E2836-10 and KS F 2809. The present results show that the speech privacy of the 5 office rooms is not met the requirement for a minimum SPC values of 70. A minimum LD value of 41 dB between the source and the receiver room should be achieved for having a SPC value of 70 when the mean measured value of $L_b$ at the receiving room is 29.2 dB. That is, the TL(avg) value averaged over the octave bands from 160 Hz to 5000 Hz between the source and the receiver room should be or greater than 40 dB. The most important architectural factor influencing the LD value is the presence of openings, such as doors, and windows, on the adjacent walls between the source and receiving room. Therefore, if the opening of the adjacent wall is replaced by an opening with high sound insulation, the appropriate SPC value of the research and office rooms can be achieved.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.4
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• pp.363-375
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• 2017

The age and growth of pointhead flounder, Hippoglossoides pinetorum caught by gill nets was analyzed in this study from March 2015 to July 2017. New annuli were formed in H. pinetorum otoliths annually, and the boundary was set between the opaque and translucent zones from March and April. The relationships between total length (TL) and body weight (BW) were $BW=0.0025TL^{3.409}$ ($r^2=0.9551$) for females and $BW=0.0057TL^{3.138}$ ($r^2=0.9163$) for males. In this study, the ring of pointhead flounder, H. pinetorum was formed between 3 and 8 for females and between 3 and 6 for males. Total length (TL) and otolith radius (OR) were measured as follows: TL = 7.142 OR + 0.769 ($r^2=0.793$) for females and TL = 6.498 OR + 1.706 ($r^2=0.652$) for males. The mean distances of first ring ($r_1$) were 0.92 mm and 0.91 mm for females and males respectively. The TLs at the time of annulus formation, back-calculated from the otolith-length relationship by reference to the von Bertalanffy growth curves, were $L_t=43.59(1-e^{-0.15(t+0.007)})$ for females and $L_t=28.13(1-e^{-0.26(t+0.006)})$ for males while the growth between female and male was different.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.272-278
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• 2008

Optimum concentration of alizarine complexone (ALC) for staining of otoliths for Pacific cod was determined by examination of stained quality, growth and survival rates. Small juveniles ($34.1{\pm}1.8mm$ TL, $mean{\pm}SD$) were immersed in four different concentrations (20, 40, 60, 80 mg/L) and large ones ($73.8{\pm}1.2mm$ TL, $mean{\pm}SD$) in five different concentrations (1, 5, 10, 20, 40 mg/L) of ALC for 24 hrs. The fish were then reared and observed for 14 days. The stained quality of otoliths was evaluated by dividing them into four grades by the presence of fluorescent stains on the otoliths under G-excited UV light. The small juveniles stained with the different ALC concentrations had 100% staining success, and their growth rate and body weight did not differ significantly between treatments. Optimal ALC concentration for the smaller juveniles was 20 mg/L in the present experiment. On the other hand, distinct fluorescent rings were confirmed on otoliths of larger juveniles in the 10 mg/L treatment with high survival rate. These results suggest that ALC staining at concentrations of 10 mg/L with larger juveniles will be helpful for release-recapture experiments for stock enhancement of Pacific cod.

• Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.169-176
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• 2012

Age and growth of Glyptocephalus stelleri in the East Sea of Korea were determined, from monthly samples of commercial catches, caught by the eastern sea Danish seine fishery in 2007. The annuli of G. stelleri are formed once a year, with the boundary between opaque and translucent zones forming in September. Relationships between total length (TL) and total weight (TW) were $TW=0.002TL^{3.392}$ ($r^2=0.970$) for females and $TW=0.002TL^{3.335}$ ($r^2=0.961$) for males. TLs at annuli formation in otoliths were back-calculated from the otolith-length relationship and were adjusted to von Bertalanffy growth curves to $L_t=39.71(1-{\exp}^{(-0.152(t+1.156))})$ for females and $L_t=32.16(1-{\exp}^{(-0.213(t+0.879))})$ for males. From the age of 3 years, females grew faster than males (P<0.05).

• Journal of Radiation Protection and Research
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• v.24 no.1
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• pp.39-43
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• 1999

Thermoluminescent (TL) response characteristics of a thin LiF:Mg,Cu,Na,Si Teflon detectors have been studied for use in beta radiation detection. The detectors were fabricated from a mixture of LiF:Mg,Cu,Na,Si phosphor and Teflon powder which was molded into a thin disk form of $50mg/cm^2$ thickness. These detectors were irradiated to beta fields of $^{147}Pm,\;^{204}Tl\;and\;^{90}Sr/^{90}Y$ sources with a covering of Kapton foil ($2mg/cm^2$) and photon irradiation was carried out with a $^{137}Cs$ source at the Korea Atomic Energy Research Institute (KAERI). Batch uniformity was estimated to be 4.7% and the beta dose response presented linear relationship from 0.1 mGy to 100 Gy. The beta energy responses of thin detectors normalized to $^{137}Cs$ were presented as 0.46, 1.09 and 1.06 for $^{147}Pm,\;^{204}Tl\;and\;^{90}Sr/^{90}Y$ beta rays, respectively. The evaluated values for angular responses were $0.93{\pm}0.03\;(^{147}Pm),\;0.94{\pm}0.04\;(^{204}Tl),\;and\;0.92{\pm}0.05\;(^{90}Sr/^{90}Y)$. The results satisfied well a proposed ISO Standard for beta ray dosimeters.

• Journal of environmental and Sanitary engineering
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• v.19 no.1
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• pp.8-16
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• 2004

Ground water samples were collected from residential, green" industrial, landfill and mining area and analyzed for 23 inorganics from March to October in 2002. The results are as follows; 1. The detection frequencies of inorganic materials such as As, Ba, B, Mo, Ca, Mg, Al, Cu, Fe, Mn, Zn, Na, K were 7.2∼77.1% which showed that these inorganics were detected in many ground waters. 2. The detection frequencies of 7 inorganics(Cd, Cr, Ph, Se, Sb, Be, Tl) were commonly low at ranging from 0.42 to 2.5%. These inorganics were contained in ground water partially. 3. Three inorganics such as Hg, Ni, Ag were not detected in any ground-water samples. 4. Compared to the other areas, ground water samples from landfill area contained greater concentration in many inorgainics and then showed higher levels in industral, residential, mining and green area in order. 5. Compared to noted concentrations of bottled water, inorganic minerals including Ca, Mg, Na, K related to taste were fluent in target samples. The results showed that the average concentrations of Mg, Na, K were 4.0 mg/l, 14.7 mg/l, 1.5 mg/l respectively. 6. The concentrations of inorganics such as Sb, Ba, Mo, Be, Tl, K in some ground water samples exceeded the water quality standards of WHO, the US and UK. Especially, Ba, Mo, K also showed relatively high detection frequencies so these inorganics need to be considered as analytes in Korea Drinking Water Regulation in further study.

• Current Research on Agriculture and Life Sciences
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• v.30 no.2
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• pp.82-89
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• 2012

Commercial powdered soups, such as potato soup(PS), corn soup(CS), and chicken-herb soup(CHS), were gamma-irradiated at 0, 1, 5 and 10 kGy and subjected to physicochemical evaluation and identification trials by analyzing photostimulated luminescence(PSL), electron spin resonance(ESR), and thermoluminescence(TL). The changes in moisture content and pH of soup samples were negligible upon irradiation. The Hunter's color determinations showed that lightness (L value) decreased and yellowness (b value) increased as the irradiation dose increased in PS sample. The viscosity of irradiated samples was reduced in the order of PS, CS and CHS. The analyses of PSL, ESR and TL were applicable to the identification of irradiated powdered-soups at more than 1 kGy by detecting PSL photon counts/60 sec(over 5000), radiation-induced multicomponents-ESR signal, and typical TL glow curve at $150-250^{\circ}C$.