• Journal of Integrative Natural Science
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• v.3 no.1
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• pp.24-27
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• 2010

Multi-functionalized rugate porous silicon (PSi) for biosensor was developed by hydrosilylation with silole and its further reaction with biotin groups. PSi was generated by an electrochemical etching of silicon wafer in aqueous ethanolic HF solution PSi prepared by using etching conditions showed that many sharp spectral lines can be obtained in the optical reflectivity spectrum. 1,1-hydrovinyl-2,3,4,5-tetraphenylsilole was obtained from the reaction of 1,1-dilithio-2,3,4,5-tetraphenyl-1,3-butadiene with dichlorovinylsilane. Multi-functionalized PSi with silole and biotin groups was characterized by UV-vis absorption spectroscopy, Ocean optics 2000 spectrometer, and fluorescence spectroscopy. Optical characteristics such as reflectivity and photoluminescence (PL) were observed. An increase of the reflection wavelength in the reflectivity spectrum by 20 nm was observed, indicative of a change in refractive indices induced by hydrosilylation of the silole and biotin groups to the rugate PSi. This red-shift was attributed to the replacement of some of the Si-H group of fresh rugate PSi with silole and biotin group.

• Progress in Medical Physics
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• v.33 no.2
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• pp.11-24
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• 2022

X-ray detection has widely been applied in medical diagnostics, security screening, nondestructive testing in the industry, etc. Medical X-ray imaging procedures require digital flat detectors operating with low doses to reduce radiation health risks. Recently, metal halide perovskites (MHPs) have shown great potential in high-performance X-ray detection because of their attractive properties, such as strong X-ray absorption, high mobility-lifetime product, tunable bandgap, low-temperature fabrication, near-unity photoluminescence quantum yields, and fast photoresponse. In this paper, we review and introduce the development status of new perovskite X-ray detectors and imaging, which have emerged as a new promising high-sensitivity X-ray detection technology. We discuss the latest progress and future perspective of MHP-based X-ray detection in medical imaging. Finally, we compare the conventional detection methods with quantum-enhanced detection, pointing out the challenges and perspectives for future research directions toward perovskite-based X-ray applications.

• The Journal of Korean Medicine
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• v.41 no.4
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• pp.1-11
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• 2020

Objectives: Objectives: The object of this study was to elucidate the possible effects on the pharmacokinetics of tamoxifen after single oral co-administration of Gamisoyo-san (GMSYS) with 2.5 hr-intervals combination therapy of tamoxifen with GMSYS. Methods: After 2.5 hr of 50 mg/kg of tamoxifen treatment, GMSYS 100 mg/kg was administered. The plasma was collected at 30 min before administration, 30 min, 1, 2, 3, 4, 6, 8 and 24 hrs after end of GMSYS treatment, and plasma concentrations of tamoxifen were analyzed using LC-MS/MS methods. PK parameters of tamoxifen were analysis as compared with tamoxifen single administered rats. Results: Although single co-administration with GMSYS with 2.5 hr-interval induced increased trends of plasma tamoxifen concentrations, there are no significant changes on the plasma concentrations of tamoxifen were demonstrated in tamoxifen and GMSYS 100 mg/kg co-administrated rats with 2.5 hr-intervals as compared to those of tamoxifen single 50 mg/kg treated rats, and also GMSYS co-administrated rats did not showed any significant changes on the all pharmacokinetic parameters as compared to those of tamoxifen single formula treated rats. Conclusions: According to the this study, single co-administration of GMSYS with 2.5 hr-intervals did not critically influenced on the oral bioavailability of tamoxifen, suggesting GMSYS did not critically influenced on the absorption and excretion of tamoxifen, the oral bioavailability, when they were co-administered with 2.5 hr-intervals, at the dose levels of tamoxifen 50 mg/kg and GMSYS 100 mg/kg.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.161-170
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• 1998

Antagonistic mode of action of fenoxaprop-P-ethyl [ethyl(R)2-4-{(6-chloro-2-benzoxazolyloxy) phenoxy}propionate] with bentazon was investigated with respect to absorption, translocation, metabolism, and change in target site response of fenoxaprop-P-ethyl using four-leaf stage of rice(Oryza sativa L.) and barnyardgrass [Echinochloa eras-galli (L.) P. Beauv.]. Shoots of rice and barnyardgrass was more sensitive to fenoxaprop-P-ethyl than the roots. More than 90% of fenoxaprop-P-ethyl was absorbed within 6 hours after treatment and 30% of the absorbed was acropetally and basipetally translocated at 24 hours after treatment. Fenoxaprop-P-ethyl was rapidly transformed to its acid form, fenoxaprop(2-[4-(6-chloro-2-benzoxazolyloxy)phenoxy]propionic acid), which was subsequently metabolized to polar conjugates. However, changes in absorption, translocation, and metabolism of fenoxaprop-P-ethyl by bentazon treatment were not found in both species. Background activity of acetyl-CoA carboxylase(ACCase) in rice and barnyardgrass was 26.5 and 23.2nmol/min/mg, respectively. Concentration required to inhibit fifty percent enzyme activity$(I_{50})$ in vitro was 6.5~7.4${\mu}M$ of fenoxaprop-P-ethyl and more than 500${\mu}M$ of bentazon. There were no significant differences in $I_{50}$ value between two treatments of fenoxaprop-P-ethyl alone and its bentazon mixture. However, bentazon reduced ACCase activity in vivo and inhibited electron transport in chloroplast thylakoid. Based on the results obtained, it is concluded that the antagonistic effect of bentazon occurs due not to direct effect on target site of fenoxaprop-P-ethyl, but to indirect involvement in reducing herbicidal activity of fenoxaprop-P-ethyl through physiological disturbances caused by bentazone at whole chloroplast level.

• The Korean Journal of Nuclear Medicine
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• v.10 no.1
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• pp.21-34
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• 1976

The diagnosis of iron deficiency rests upon the correct evaluation of body iron stores. Morphological interpretation of blood film and the red cell indices are not reliable and often absent in mild iron deficiency. Serum iron levels and iron-binding capacity are more sensitive indices of iron deficiency, but they are often normal in iron depletion and mild iron deficiency anemia. They are also subject to many variables which may introduce substantial errors and influenced by many pathologic and physiologic states. Examination of the bone marrow aspirate for stainable iron has been regarded as one of the most sensitive and reliable diagnostic method for detecting iron deficiency, but this also has limitations. Thus, there is still need for a more practical, but sensitive and reliable substitute as a screening test of iron deficiency. Pollack et al. (1965) observed that the intestinal absorption of cobalt was raised in iron-deficient rats and Valberg et al. (1969) found that cobalt absorption was elevated in patients with iron deficiency. A direct correlation was demonstrated between the amounts of radioiron and radiocobalt absorbed. Unlike iron, excess cobalt was excreted by the kidney, the percentage of radioactivity in the urine being directly related to the percentage absorbed from the gastrointestinal tract. Recently a test based on the urinary excretion of an oral dose of $^{57}Co$ has been proposed as a method for detecting iron deficiency. To assess the diagnostic value of urinary cobalt excretion test cobaltous chloride labelled with $1{\mu}Ci\;of\;^{58}Co$ was given by mouth and the percentage of the test dose excreted in the urine was measured by a gamma counter. The mean 24 hour urinary cobalt excretion in control subjects with normal iron stores was 6.1% ($1.9{\sim}15.2%$). Cobalt excretion was markedly increased in patients with iron deficiency and excreted more than 29% of the dose. In contrast, patients with anemia due to causes other than iron deficiency excreted less than 27%. Hence, 24 hour urinary cobalt excretion of 27% or less in a patient with anemia suggets that the primary cause of the anemia is not iron deficiency. A value greater than 27% in an anemic subject suggests that the anemia is caused by iron deficiency. The cobalt excretion test is a simple, sensitive and accurate method for the assessment of body iron stores. It may be particularly valuable in the epidemiological studies of iron deficiency and repeated evaluations of the body iron stores.

• Transactions of the Korean hydrogen and new energy society
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• v.24 no.2
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• pp.128-135
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• 2013

The nuclear fuel cycle plant is composed of various subsystems such as a fuel storage and delivery system (SDS), a tokamak exhaust processing system, a hydrogen isotope separation system, and a tritium plant analytical system. Korea is sharing in the construction of the International Thermonuclear Experimental Reactor (ITER) fuel cycle plant with the EU, Japan, and the US, and is responsible for the development and supply of the SDS. Hydrogen isotopes are the main fuel for nuclear fusion reactors. Metal hydrides offer a safe and convenient method for hydrogen isotope storage. The storage of hydrogen isotopes is carried out by absorption and desorption in a metal hydride bed. These reactions require heat removal and supply respectively. Accordingly, the rapid storage and delivery of hydrogen isotopes are enabled by a rapid cooling and heating of the metal hydride bed. In this study, we designed and manufactured a vertical-type hydrogen isotope storage bed, which is used to enhance the cooling performance. We present the experimental details of the cooling performances of the bed using various cooling parameters. We also present the modeling results to estimate the heat transport phenomena. We compared the cooling performance of the bed by testing different cooling modes, such as an isolation mode, a natural convection mode, and an outer jacket helium circulation mode. We found that helium circulation mode is the most effective which was confirmed in our model calculations. Thus we can expect a more efficient bed design by employing a forced helium circulation method for new beds.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.11-18
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• 1994

We have studied the iron uptake by the purified brush-border membrane vesicles (BBMVs) to determine the effect of fructose on the absorption of iron. BBMVs were prepared by the modified calcium precipitation method, The degree of purification was routinely assessed by the marker enzyme, alkaline phosphatase, and the functional integrity was tested by $D-[1-^3H]glucose$ uptake. The appearance of membrane vesicles was shown by transmission electron microscopy (TEM). The uptakes of complexes of labeled iron $[^{59}Fe]$ with fructose and ascorbate were measured with a rapid filtration technique, The uptake rate and pattern of the two iron-complexes, Fe(III)-fructose and Fe(III)-ascorbate, were also observed. A typical overshooting uptake of D-glucose was observed with peak value of $2{\sim}3$ times higher concentration than that at equilibrium. This result was similar to other studies with BBMVs. TEM showed that the size of BBMVs was uniform and we can hardly find any contaminants, Fe(III)-fructose has the higher value of $V_{max}$ and the lower value of Km than those of Fe(III)-ascorbate, respectively. It may be concluded that D-fructose is more effective in promoting the iron absorption than ascorbate.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.2
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• pp.139-155
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• 2013

Purpose : This study was aim to evaluate effects of pharmacodynamics and toxicity in combination therapy of donepezil with Gongjindan. The effects of Gongjindan co-administration on the pharmacokinetics (PK) of donepezil were observed after single and 7-day repeated oral co-administration with 1.5hr-intervals, to evaluate synergic pharmacodynamics and reduce toxicity of combination therapy of donepezil with Gongjindan. Materials and Methods : After 10mg/kg of donepezil treatment, Gongjindan100mg/kg was administered with 1.5hr-intervals. The plasma were collected at 30min before administration, 30min, 1, 2, 3, 4, 6, 8 and 24hrs after end of first and last 7th donepezil treatment, and plasma concentrations of donepezil were analyzed using LC-MS/MS methods. Results : Gongjindan markedly inhibited the absorption of donepezilregardless of sample time, from 30min to 8hrs after end of first 1.5hr-interval co-administration as compared with donepezil single treated rats. Especially the absorption of donepezil was significantly decreased at 2, 4, 6 and 8hrs after co-administration as compared with donepezilsingle treated rats. Accordingly, the Cmax (-26.236%), $AUC_{0-t}$(-26.02%) and $AUC_{0-inf}$(-25.90%) of donepezil in 1.5hr-interval co-administered rats were dramatically decreased as compared with donepezilsingle treated rats, respectively. However, no meaningful changes on the plasma donepezil concentrations and pharmacokinetic parameters were detected after end of last 7th 1.5hr-interval co-administration as compared with donerezil single treated rats, except for non-significant slight increases of Tmax(16.67%) detected in co-administered rats as compared with donepezil single treated rats. Conclusion : These findings are considered as direct evidences that Gongjindan also decreased oral bioavailability of donerezil as inhibited the absorptions, when they were co-administered with 1.5hr-intervals, but they may be adapted after 7 days continuous repeated l.5hr-interval co-administration.

• Journal of Pharmaceutical Investigation
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• v.38 no.6
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• pp.421-427
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• 2008

The purpose of the present study was to evaluate the bioequivalence of two etodolac capsules, Kuhnillodin capsule (Kuhnil. Co., Ltd., Seoul, Korea) as reference drug and Etodin capsule (Myungmun Pharm. Co., Ltd., Seoul, Korea) as test drug, according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty-three healthy male Korean volunteers received one capsule at the dose of 200 mg etodolac in a $2{\times}2$ crossover study. There was a one-week washout period between the doses. Plasma concentrations of etodolac were monitored by a high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) for over a period of 24 hr after the administration. $AUC_{0-24\;hr}$ was calculated by the linear trapezoidal rule method. $C_{max}$ and $T_{max}$ were compiled from the plasma concentration-time data. Analysis of variance (ANOVA) was carried out using logarithmically transformed $AUC_{0-24\;hr}$ and $C_{max}$. The 90% confidence intervals of the $AUC_{0-24\;hr}$ ratio and the $C_{max}$ ratio for Etodin/Kuhnillodin were $\log\;0.97{\sim}\log\;1.08$ and $\log\;0.89{\sim}\log\;1.19$, respectively. These values were within the acceptable bioequivalence intervals of $\log\;0.80{\sim}\log\;1.25$. Thus, our study demonstrated that Etodin was bioeqiovalent to Kuhnillodin preparation when the rate and extent of absorption between two preparations were compared.

• Journal of Pharmaceutical Investigation
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• v.34 no.4
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• pp.319-325
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• 2004

A bioequivalence of $Etodol^{TM}$ tablets (Yuhan corporation) and $Kuhnillodine^{TM}$ tablets (Kuhnil Pharm. Co., Ltd.) was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). Single 200 mg dose of etodolac of each medicine was administered orally to 24 healthy male volunteers. This study was performed in a $2{\times}2$ crossover design. Concentrations of etodolac in human plasma were monitored by a high-performance liquid chromatography. $AUC_t$ (the area under the plasma concentration-time curve from time zero to 24 hr) was calculated by the linear trapezoidal rule method. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was performed using logarithmically transformed $AUC_t$ and $C_{max}$. No significant sequence effect was found for all of the bioavailability parameters. The 90% confidence intervals of the $AUC_t$ ratio and the $C_{max}$ ratio for $Etodol^{TM}/Kuhnillodine^{TM}$ were 1.01-1.10 and 0.87-1.06, respectively. This study demonstrated a bioequivalence of $Etodol^{TM}$ and $Kuhnillodine^{TM}$ with respect to the rate and extent of absorption.