• Journal of Nutrition and Health
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• v.26 no.5
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• pp.532-546
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• 1993

This study was done to investigate the effects of different dietary oils on hepatic mitochondrial lipid compositon, adenine nucleotide translocase(AdNT) and ATPase activities in carcinogen treated rats. Sixty male Sprague-Dawley rats, weighing 50∼60g, were fed three different types of dietary oil, beef tallow(BT), corn oil(CO) and sardine oil(SO) at 15% by weight for 14 weeks. Three weeks after feeding rats were intraperitoneally injected with a single dose of diethylnitrosamine(200mg/Kg BW). After five weeks rate fed 0.02% acetylaminofluorene contating diet for 6 weeks, and after seven weeks 0.05% phenobarbital containing diet for 7 weeks. At 14th week, rats were sacrificed and hepatic mitochondrial lipid composition, AdNT and ATPase activities were determined. Percent liver weight per body weight was significantly by carcinogen treatment. Analysis of mitochondrial lipid composition showed that body cholesterol and phospholipid contents were not affected by dietary oils but significantly increased by carcinogen treatment. Individual phospholipid composition as well as phosphatidyl ethanolamine/phosphatidyl choline ratio were altered by either dietary oils or carcinogen treatment. Fatty acid composition was changed by dietary oils but not much by carcinogen treatment. AdNT activity was affected by dietary oils in only carcinogen treated groups. ATPase activity was affected by dietary oils in only carcinogen nontreated groups. These data indicate that both dietary oils and caricinogen treatment can change mitochondrial lipid composition and thereby change AdNT and ATPase activities. Particularly effects of carcinogen treatment on cholesterol/phopholipid ratio, phospholipid compositon and ATPase activity were different among dietary oil groups. Therefore it is suggested that different dietary oils can somewhat modulate the changes of mitochnodrial lipid composition and membrane bound enzyme activites during hepatocarcinogenesis.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.87-92
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• 1996

This study describes a stable and simple method for the measurement of cholesteryl ester transfer protein(CETP) activities using reconstituted HDL and LDL as substrates. Apolipoproteins (apo) A-I and -B were purified from hog plasma by a new strategy without ultracentrifugation and delipidation. a simple two-step column chromatography was administered. In the first step of phenyl-sepharose CL-4B column chro-matography, hydrophobic plasma proteins were isolated. The most hydrophobic proteins bound to the column appeared to be A-I and apo-B. Contaminat proteins were efficiently eliminated from the sample by washing the column with 0.3M NaCI containing buffer after loading the plasma on the column. Two pure proteins showing each single band on SDS-PSGE of apo A-I and apo-B were individually obtained by a subsequent gel filtration column chromatography(Sephadex G-200). This two-step purification was simple and inexpensive compared to the ultracentrifugation and/or delipidation method that are most commonly used. Reconstituted hight-density lipoproteins(HDL) and low-density lipoproteins(LDL) were prepared using the purified apo A-I and-B, respectively. When these artificially prepared HDL and LDL were used in the assays for CETP as the cholesteryl ester(CE) donor and acceptor respectively, the specific transfer of CE increased up to two fold compared to that used the native HSL and LDL.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1222-1227
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• 1998

The crystal structure of a benzene sorption complex of fully dehydrated Cd2+-exchanged zeolite X, Cd46Si100Al92O384·43C6H6 (a=24.880(6) Å), has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21 ℃. The crystal was prepared by ion exchange in a flowing stream of 0.05 M aqueous Cd(NO3)2 for 3 d, followed by dehydration at 400 ℃ and 2 x 10-6 Torr for 2 d, followed by exposure to about 92 Torr of benzene vapor at 22 ℃. The structure was determined in this atmosphere and refined to the final error indices R1=0.054 and Rw=0.066 with 561 reflections for which I > 3σ(I). In this structure, Cd2+ ions are found at four crystallographic sites: eleven Cd2+ ions are at site 1, at the centers of the double six-oxygen rings; six Cd2+ ions lie at site I', in the sodalite cavity opposite to the double six-oxygen rings; and the remaining 29 Cd2+ ions are found at two nonequivalent threefold axes of unit cell, sites Ⅱ' (in the sodalite cavity ) and site Ⅱ (in the supercage) with occupancies of 2 and 27 ions, respectively. Each of these Cd2+ ions coordinates to three framework oxylkens, either at 2.173(13) or 2.224(10) Å, respectively, and extends 0.37 Å into the sodalite unit or 0.60 Å into the supercage from the plane of the three oxygens to which it is bound. The benzene molecules are found at two distinct sites within the supercages. Twenty-seven benzenes lie on threefold axes in the large cavities where they interact facially with the latter 27 site-Ⅱ Cd2+ ions (Cd2+-benzene center=2.72 Å; occupancy=27 molecules/32 sites). The remaining sixteen benzene molecules are found in 12ring planes; occupancy=16 molecules/16 sites. Each hydrogen of these sixteen benzenes is ca. 2.8/3.0 Å from three 12-ring oxygens where each is stabilized by multiple weak electrostatic and van der Waals interactions with framework oxygens.

• Investigative Magnetic Resonance Imaging
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• v.23 no.3
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• pp.202-209
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• 2019

Purpose: To investigate the temperature-based differences of cortical bone ultrashort echo time MRI (UTE-MRI) biomarkers between body and room temperatures. Investigations of ex vivo UTE-MRI techniques were performed mostly at room temperature however, it is noted that the MRI properties of cortical bone may differ in vivo due to the higher temperature which exists as a condition in the live body. Materials and Methods: Cortical bone specimens from fourteen donors ($63{\pm}21$ years old, 6 females and 8 males) were scanned on a 3T clinical scanner at body and room temperatures to perform T1, $T2^*$, inversion recovery UTE (IR-UTE) $T2^*$ measurements, and two-pool magnetization transfer (MT) modeling. Results: Single-component $T2^*$, $IR-T2^*$, short and long component $T2^*s$ from bi-component analysis, and T1 showed significantly higher values while the noted macromolecular fraction (MMF) from MT modeling showed significantly lower values at body temperature, as compared with room temperature. However, it is noted that the short component fraction (Frac1) showed higher values at body temperature. Conclusion: This study highlights the need for careful consideration of the temperature effects on MRI measurements, before extending a conclusion from ex vivo studies on cortical bone specimens to clinical in vivo studies. It is noted that the increased relaxation times at higher temperature was most likely due to an increased molecular motion. The T1 increase for the studied human bone specimens was noted as being significantly higher than the previously reported values for bovine cortical bone. The prevailing discipline notes that the increased relaxation times of the bound water likely resulted in a lower signal loss during data acquisition, which led to the incidence of a higher Frac1 at body temperature.

• Journal of Advanced Navigation Technology
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• v.26 no.4
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• pp.226-234
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• 2022

With advances in autonomous vehicles and networked control, there is a growing interest in the consensus control of a multi-agents system to control multi-agents with distributed control beyond the control of a single agent. Since consensus control is a distributed control, it is bound to have delay in a practical system. In addition, it is often difficult to have a very accurate mathematical model for a system. Even though a reinforcement learning (RL) method was developed to deal with these issues, it often experiences slow convergence in the presence of large uncertainties. Thus, we propose a slide RL which combines the sliding mode control with RL to be robust to the uncertainties. The structure of a sliding mode control is introduced to the action in RL while an auxiliary sliding variable is included in the state information. Numerical simulation results show that the slide RL provides comparable performance to the model-based consensus control in the presence of unknown time-varying delay and disturbance while outperforming existing state-of-the-art RL-based consensus algorithms.

• Molecules and Cells
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• v.46 no.8
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• pp.513-525
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• 2023

Orange carotenoid protein (OCP) of photosynthetic cyanobacteria binds to ketocarotenoids noncovalently and absorbs excess light to protect the host organism from light-induced oxidative damage. Herein, we found that mutating valine 40 in the α3 helix of Gloeocapsa sp. PCC 7513 (GlOCP1) resulted in blue- or red-shifts of 6-20 nm in the absorption maxima of the lit forms. We analyzed the origins of absorption maxima shifts by integrating X-ray crystallography, homology modeling, molecular dynamics simulations, and hybrid quantum mechanics/molecular mechanics calculations. Our analysis suggested that the single residue mutations alter the polar environment surrounding the bound canthaxanthin, thereby modulating the degree of charge transfer in the photoexcited state of the chromophore. Our integrated investigations reveal the mechanism of color adaptation specific to OCPs and suggest a design principle for color-specific photoswitches.

• Journal of Microbiology and Biotechnology
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• v.33 no.9
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• pp.1170-1178
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• 2023

Food allergy represents a severe problem for many societies, including sensitive populations, academies, health authorities, and the food industry. Peanut allergy occupies a special place in the food allergy spectrum. To prevent consumption by consumers suffering from a peanut allergy, a rapid and sensitive detection method is essential to identify unintended peanut adulteration in processed foods. In this study, we produced four monoclonal antibodies (MAbs; RO 3A1-12, PB 4C12-10, PB 5F9-23, and PB 6G4-30) specific to thermo-stable and soluble proteins (TSSPs) of peanut and developed an enzyme-linked immunosorbent assay (ELISA) based on the MAbs. Among them, PB 5F9-23 MAb was firmly bound to Ara h 1, and other MAbs strongly reacted to Ara h 3 in the Western blot analysis. An antibody cocktail solution of the MAbs was used to enhance the sensitivity of an indirect ELISA, and the limit of detection of the indirect ELISA based on the antibody cocktail solution was 1 ng/ml and improved compared to the indirect ELISA based on the single MAb (11 ng/ml). The cross-reaction analysis revealed the high specificity of developed MAbs to peanut TSSPs without cross-reaction to other food allergens, including nuts. Subsequently, analyzing processed foods by indirect ELISA, all foods labeled as containing peanuts in the product description were confirmed to be positive. The results indicate that the developed antibodies exhibit high specificity and sensitivity to peanuts and can be used as bio-receptors in immunoassays or biosensors to detect intentional or unintentional adulteration of peanuts in processed foods, particularly heat-processed foods.

• Food Science of Animal Resources
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• v.20 no.2
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• pp.159-165
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• 2000

Glycomacropeptide(GMP) was purified from cheese whey which is obtaining as a byproduct in cheese producing. Cheese whey was first concentrated 10 times with a ultrafiltration aparratus, and then heated at 95$^{\circ}C$ for 5 min. The concentrated fraction was centrifuged at 20,000$\times$g for 30 min to remove fat layer. The supernatant layer enriched GMP protein was fractionated by ion exchange chromatography on DEAE-Sepharose Fast Flow column. GMP was bound to DEAE resin and eluted with 0.1~0.25 M NaCl when using a linear NaCl gradient from 0 M to 0.5 M. The purified GMP gave a single band of 24 kDa which seems to be trimer molecular weight in SDS-PAGE, and migrated to the same molecular weight with control GMP obtained commercially. Its amino acid composition were consistent with that of standard GMP. About 0.71 g of GMP was recovered from 1 L of cheese whey. These results indicate that glycomacropeptide could be simply purified from cheese whey by using ultrafiltration and DEAE column chromatography.

• Biomolecules & Therapeutics
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• v.3 no.1
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• pp.21-27
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• 1995

The only compounds with antagonistic activity via AT$_1$receptor, one of two subtypes of angiotensin II (AII) receptor, have been demonstrated to block the vasoconstriction effects of AII and thereby provide therapeutic potential. This initiated the search for compounds with high specific affinity to AT$_1$receptor and their effective screening methods. The radioligand binding assay for the AII receptor is regarded as the primary method for the evaluation of AT$_1$receptor antagonists for their activity. In this paper, we characterized the liver AT$_1$receptor and describe the efficient method of the radioligand binding assay using rat liver as a source of AT$_1$receptor. Equilibrium binding studies with rat adrenal cortex, adrenal medulla, liver and bovine adrenal showed that the specific bindings of [$^3$H] AII were saturable in all tissues and the Scatchard plots of those data were linear, suggesting a single population of binding sites. Hill slopes were very near to the unity in all tissues. Kinetic studies of [$^3$H) AII binding in rat liver homogenates yielded two association rate constants, 4.10$\times$10$^{7}$ M$^{-1}$ min$^{-1}$ and 4.02$\times$10$^{9}$ M$^{-1}$ min$^{-1}$ , with a single dissociation rate constant, 7.07$\times$10$^{-3}$ min-$^{-1}$ , possibly due to the partial dissociation phenomenon. The rank order of inhibition potencies of [$^3$H] AII binding in rat liver was AII>Sarile>Losartan>PD 123177. Rat liver homogenates revealed to have very high density of homogeneous population of the AT$_1$receptor subtype, as the specifically bound [$^3$H] AII was not inhibited by PD 123177, the nonpeptide antagonist of AT$_2$. The results of this study demonstrated that the liver homogenates from rats could be the best receptor preparation for the AT$_1$receptor binding assay and provide an efficient system for the screening of newly synthesized candidate compounds of AT$_1$receptor antagonist.

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.651-657
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• 2019

Although smallpox was eradicated in 1980, it is still considered a potential agent of biowarfare and bioterrorism. Smallpox has the potential for high mortality rates along with a major public health impact, eventually causing public panic and social disruption. Passive administration of neutralizing monoclonal antibodies (mAbs) is an effective intervention for various adverse reactions caused by vaccination and the unpredictable nature of emerging and bioterrorist-related infections. Currently, vaccinia immune globulin (VIG) is manufactured from vaccinia vaccine-boosted plasma; however, this production method is not ideal because of its limited availability, low specific activity, and risk of contamination with blood-borne infectious agents. To overcome the limitations of VIG production from human plasma, we isolated two human single-chain variable fragments (scFvs), (SC34 and SC212), bound to vaccinia virus (VACV), from a scFv phage library constructed from the B cells of VACV vaccine-boosted volunteers. The scFvs were converted to human IgG1 (VC34 and VC212). These two anti-VACV mAbs were produced in Chinese Hamster Ovary (CHO) DG44 cells. The binding affinities of VC34 and VC212 were estimated by competition ELISA to $IC_{50}$ values of $2{\mu}g/ml$ (13.33 nM) and $22{\mu}g/ml$ (146.67 nM), respectively. Only the VC212 mAb was proven to neutralize the VACV, as evidenced by the plaque reduction neutralization test (PRNT) result with a $PRNT_{50}$ of ~0.16 mg/ml (${\sim}1.07{\mu}M$). This VC212 could serve as a valuable starting material for further development of VACV-neutralizing human immunoglobulin for a prophylactic measure against post-vaccination complications and for post-exposure treatment against smallpox.