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Li L, Gorukanti S, Choi YM, Kim KH. Rapid-onset intranasal delivery of anticonvulsants: pharmacokinetic and pharmacodynamic evaluation in rabbits. Int J Pharm 2000; 199:65-76. [PMID: 10794928 DOI: 10.1016/s0378-5173(00)00373-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Intranasal (IN) administration is a promising approach for rapid-onset delivery of medications. In order to assess the feasibility of this approach for the emergency treatment of status epilepticus, three anticovulsants, i.e. diazepam (DZ), clonazepam (CZ), and a monocarbamate-based new compound (MCA) were studied in rabbits for the pharmacokinetics (PK) and pharmacodynamic (PD) response following intravenous (IV) and IN administrations. The animals were intranasally dosed with DZ (1 mg/kg), CZ (0.2 mg/kg), and MCA (5 mg/kg), dissolved in 200 microl of vehicle consisting of propylene glycol (PG), ethanol (EtOH), and water in the presence or absence of 1% sodium glycocholate (SGC) using single and repeated dosing schedules. Both DZ and CZ were absorbed very rapidly from 1% SGC/60% PG-30% EtOH-10% Water after IN single application; the T(max)'s were less than 2 min. The absorption rate of MCA was relatively slower with the peak time of 13-32 min. The bioavailability of single IN administration for DZ, CZ, and MCA determined over the first 2 or 4 h was found to be 77, 45, and 79%, respectively. The peak plasma level of DZ increased linearly with increasing the volume fraction of EtOH in the ternary cosolvent (20% to 60%). A repeated IN application of DZ, 5 min after the first dose, doubled the C(max) and AUC(0-2 h) values of the first one, whereas those of CZ and MCA resulted in an increase of 73-94% of the first dose. A single IN application of DZ- and CZ-containing formulations produced a PD response within 1.5 min, which was comparable to that of an IV injection. These results suggest that single or repeated IN applications of DZ, CZ, and MCA in a hydroalcohol-glycolic formulation might represent a viable approach to achieving a rapid systemic absorption of these anticonvulsants during the emergency treatment of status epilepticus and other types of seizures.
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477
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Moon YS, Latasa MJ, Kim KH, Wang D, Sul HS. Two 5'-regions are required for nutritional and insulin regulation of the fatty-acid synthase promoter in transgenic mice. J Biol Chem 2000; 275:10121-7. [PMID: 10744693 DOI: 10.1074/jbc.275.14.10121] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We previously reported that 2.1 kilobase pairs of the 5'-flanking sequence are sufficient for tissue-specific and hormonal/metabolic regulation of the fatty-acid synthase (FAS) gene in transgenic mice. We also demonstrated that the -65 E-box is required for insulin regulation of the FAS promoter using 3T3-L1 adipocytes in culture. To further define sequences required for FAS gene expression, we generated transgenic mice carrying from -644, -444, -278, and -131 to +67 base pairs of the rat FAS 5'-flanking sequence fused to the chloramphenicol acetyltransferase (CAT) reporter gene. Similar to the expression observed with -2100-FAS-CAT transgenic mice, transgenic mice harboring -644-FAS-CAT and -444-FAS-CAT expressed high levels of CAT mRNA only in lipogenic tissues (liver and adipose tissue) in a manner identical to the endogenous FAS mRNA. In contrast, -278-FAS-CAT and -131-FAS-CAT transgenic mice did not show appreciable CAT expression in any of the tissues examined. When previously fasted mice were refed a high carbohydrate, fat-free diet, CAT mRNA expression in transgenic mice harboring -644-FAS-CAT and -444-FAS-CAT was induced dramatically in liver and adipose tissue. The induction was virtually identical to that observed in -2100-FAS-CAT transgenic mice and to the endogenous FAS mRNA. In contrast, -278-FAS-CAT transgenic mice showed induction by feeding, but at a much lower magnitude in both liver and adipose tissue. The -131-FAS-CAT transgenic mice did not show any CAT expression either when fasted or refed a high carbohydrate diet. To study further the effect of insulin, we made these transgenic mice insulin-deficient by streptozotocin treatment. Insulin administration to the streptozotocin-diabetic mice increased CAT mRNA levels driven by the -644 FAS and -444 FAS promoters in liver and adipose tissue, paralleling the endogenous FAS mRNA levels. In the case of -278-FAS-CAT, the induction observed was at a much lower magnitude, and deletion to -131 base pairs did not show any increase in CAT expression by insulin. This study demonstrates that the sequence requirement for FAS gene regulation employing an in vitro culture system does not reflect the in vivo situation and that two 5'-flanking regions are required for proper nutritional and insulin regulation of the FAS gene. Cotransfection of the upstream stimulatory factor and various FAS promoter-luciferase constructs as well as in vitro binding studies suggest a function for the upstream stimulatory factor at both the -65 and -332 E-box sequences.
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478
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Kim KH, Bae JH, Cha SW, Han SS, Park KH, Jeong TC. Role of metabolic activation by cytochrome P450 in thioacetamide-induced suppression of antibody response in male BALB/c mice. Toxicol Lett 2000; 114:225-35. [PMID: 10713488 DOI: 10.1016/s0378-4274(00)00168-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Effects of thioacetamide on antibody response to sheep red blood cells were investigated in male BALB/c mice. When mice were treated intraperitoneally with thioacetamide once, the antibody response was significantly suppressed at 200 mg/kg with hepatotoxicity. When mice were treated intraperitoneally with thioacetamide for 7 consecutive days, the antibody response was suppressed at 50 mg/kg without hepatotoxicity. To determine the possible role of metabolic activation by cytochrome P450 in thioacetamide-induced suppression of antibody response, mice were pretreated with phenobarbital intraperitoneally for 3 days, followed by intraperitoneal administration of 100 mg/kg of thioacetamide for 3 days. The elevated activities of serum aspartate aminotransferase and alanine aminotransferase by thioacetamide were potentiated by phenobarbital pretreatment. The suppression of antibody response by thioacetamide was potentiated by phenobarbital. In liver microsomes, the activities of P450 2B-specific enzymes were induced by phenobarbital. Our present results suggest that thioacetamide may require metabolic activation by P450 to its immunosuppressive form(s).
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479
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Ryu KH, Rhee HI, Jung I, Kim TS, Lee SJ, Im GJ, Lee N, Ryu DH, Kim YW, Kim JJ, Chang K, Lee BH, Shin HS, Kim EJ, Kim KH, Kim DK. General pharmacology of the new antiviral agent SK 1899. ARZNEIMITTEL-FORSCHUNG 2000; 50:395-403. [PMID: 10800640 DOI: 10.1055/s-0031-1300220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The general pharmacological properties of 2-amino-9-(3-acetoxymethyl-4-isopropoxycarbonyloxybut-1-yl)purine (CAS 247081-81-8, SK 1899), a new potential antiviral agent, were investigated in mice, rats, guinea pigs, rabbits, and dogs. The oral administration of 50, 150, and 500 mg/kg of SK 1899 had no effects on the central nervous system except that it slightly increased the spontaneous locomotor activity in mice at a dose of 500 mg/kg. SK 1899 did not disturb either the spontaneous motility or contractor-induced contraction of the isolated organs such as guinea pig ileum, rat uterus, guinea pig vas deferens, and guinea pig trachea at concentrations up to 10(-4) mol/l. It slightly increased the contractile force in the isolated guinea pig atrium at a concentration of 10(-4) mol/l. Following intravenous infusion of 5, 15, and 50 mg/kg of SK 1899 to anesthetized dogs, it did not change the mean arterial pressure, heart rate, left ventricular systolic pressure (LVSP), and respiratory rate, while it slightly increased the left ventricular positive dP/dtmax (LV + dP/dtmax) at a dose of 50 mg/kg. SK 1899 did not induce any significant changes in the intestinal charcoal meal transit in mice, basal gastric juice secretion in rats, and renal function in rats. It did not affect the blood coagulation system and phenolsulfonphthalein secretion in rats. These findings suggest that SK 1899 has a very low potential to induce any adverse pharmacological effects at the doses showing antiviral activity.
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480
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Belogortseva NI, Yoon JY, Kim KH. Inhibition of Helicobacter pylori hemagglutination by polysaccharide fractions from roots of Panax ginseng. PLANTA MEDICA 2000; 66:217-220. [PMID: 10821045 DOI: 10.1055/s-2000-8658] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Polysaccharides from the roots of Panax ginseng were extracted by hot water and fractionated by using ethanol precipitation and ion exchange chromatography. Fractions FC (crude extract), F1 (fraction precipitated by ethanol), F1N (fraction unbound to DEAE-Sepharose CL-6B), and F1A (bound fraction) were obtained. Their carbohydrate analyses showed that acidic fraction F1A contains higher amounts of galactose, arabinose and uronic acids, in comparison to FC and F1. Fraction F1N mainly consists of glucose. The inhibition of Helicobacter pylori-induced hemagglutination revealed different inhibitory activities of these fractions. In particular, acidic fraction F1A showed a remarkable inhibitory activity (minimum inhibition concentration was 0.25 mg/ml) among the polysacharide fractions. However, digestion of the fraction F1A with pectinase resulted in a lower molecular weight oligosaccharide fraction F1AP which was non-inhibitory at the concentration of 4 mg/ml. Comparison of inhibitory activities and carbohydrate compositions of isolated fractions indicates that the activity correlated with the contents of galactose, arabinose, and uronic acids. These data suggest that acidic polysaccharides may be responsible for the inhibitory activity.
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481
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Meyer MD, Decker MW, Rueter LE, Anderson DJ, Dart MJ, Kim KH, Sullivan JP, Williams M. The identification of novel structural compound classes exhibiting high affinity for neuronal nicotinic acetylcholine receptors and analgesic efficacy in preclinical models of pain. Eur J Pharmacol 2000; 393:171-7. [PMID: 10771011 DOI: 10.1016/s0014-2999(00)00041-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Neuronal nicotinic acetylcholine receptors represent a new and potentially useful target for the development of novel non-opioid, non-NSAID (nonsteroidal antiinflammatory drug) analgesic agents. A variety of nicotinic acetylcholine receptor agonists such as nicotine, epibatidine and the azetidinyl ether, (R)-5-(2-azetidinylmethoxy-2-chloropyridine (ABT-594) possesses significant efficacy in preclinical models of pain. A preponderance of evidence suggests that nicotinic acetylcholine receptor agonists produce their analgesic effects predominantly via activation of descending inhibitory pain pathways originating in the key brainstem regions of the nucleus raphe magnus, dorsal raphe, and locus coeruleus, and that alpha4-containing nicotinic acetylcholine receptor subunits mediate these effects. Although these studies may provide a pharmacological target for the development of nicotinic acetylcholine receptor analgesics, the rational design of selective ligands based on the protein structure of the binding site is hampered by insufficient structural information. Using an approach based upon homology to known high-affinity ligands for the alpha4beta2 binding site, a four-point model is proposed which defines distance and directionality parameters common to this set of nicotinic acetylcholine receptor ligands.
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482
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Kim KH, Uehara M, Hess C, Sharma PA, Cheong SW. Thermal and electronic transport properties and two-phase mixtures in La(5/8-x)Pr(x)Ca(3/8)MnO3. PHYSICAL REVIEW LETTERS 2000; 84:2961-2964. [PMID: 11018986 DOI: 10.1103/physrevlett.84.2961] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/1999] [Indexed: 05/23/2023]
Abstract
We measured thermal conductivity kappa, thermoelectric power S, and electric conductivity sigma of La(5/8-x)Pr(x)Ca(3/8)MnO3, showing an intricate interplay between metallic ferromagnetism (FM) and charge ordering (CO) instability. The change of kappa, S, and sigma with temperature (T) and x agrees well with the effective medium theories for binary metal-insulator mixtures. This agreement clearly demonstrates that with the variation of T as well as x, the relative volumes of FM and CO phases drastically change and percolative metal-insulator transition occurs in the mixture of FM and CO domains.
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483
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Kim KH, Kim YB, Okuno O. Microfracture mechanisms of composite resins containing prepolymerized particle fillers. Dent Mater J 2000; 19:22-33. [PMID: 11219088 DOI: 10.4012/dmj.19.22] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effect of prepolymerized particle fillers on fracture toughness of four commercial composite resins was studied. The ground surface morphology was examined with a field emission scanning electron microscope. Fracture toughness was determined by using single edge notched specimens. Acoustic Emission (AE), which is the elastic wave due to the release of energy from the localized sources of material, was detected by sensors of a high-sensitivity and low-noise resonance type during the fracture toughness test. Acoustic Emission signals detected were analyzed for parameters such as amplitude and energy. Fracture surfaces were examined with a scanning electron microscope. The fracture toughness values, AE releasing patterns during fracture toughness test, and the fracture surface findings were analyzed to understand the fracture behavior of composite resins containing prepolymerized particle fillers. A microfracture model and fracture mechanisms to increase the fracture toughness of this type of composite resins are proposed.
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484
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Kim H, Seo JY, Kim KH. Inhibition of lipid peroxidation, NF-kappaB activation and IL-8 production by rebamipide in Helicobacter pylori-stimulated gastric epithelial cells. Dig Dis Sci 2000; 45:621-8. [PMID: 10749342 DOI: 10.1023/a:1005474013988] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The present study aimed to investigate whether rebamipide, a novel antiulcer agent that has an oxygen radical scavenging activity, would inhibit lipid peroxidation, NF-kappaB activation, and IL-8 production by H. pylori. Human gastric epithelial cells (AGS and KATO III), treated with rebamipide or not were incubated in the absence or the presence of H. pylori. As a result, H. pylori significantly stimulated IL-8 production, which was similar to time course stimulation of lipid peroxidation. Other cytokines (IL-1alpha, IL-1beta, IL-6, TNF-alpha) were not stimulated by H. pylori. Treatment with H. pylori resulted in the activation of two species of NF-kappaB dimers (a p50/p65 heterodimer and a p50 homodimer). Rebamipide significantly inhibited lipid peroxidation as an indicative of oxidative damage, NF-kappaB complex formation, and IL-8 production by H. pylori. In conclusion, rebamipide may attenuate H. pylori-induced gastric inflammation by inhibiting lipid peroxidation and oxidant-mediated activation of NF-kappaB and thereby decreasing IL-8 production.
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485
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Houghton J, Macera-Bloch LS, Harrison L, Kim KH, Korah RM. Tumor necrosis factor alpha and interleukin 1beta up-regulate gastric mucosal Fas antigen expression in Helicobacter pylori infection. Infect Immun 2000; 68:1189-95. [PMID: 10678925 PMCID: PMC97266 DOI: 10.1128/iai.68.3.1189-1195.2000] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Fas-mediated gastric mucosal apoptosis is gaining attention as a cause of tissue damage due to Helicobacter pylori infection. We explored the effects of H. pylori directly, and the effects of the inflammatory environment established subsequent to H. pylori infection, on Fas-mediated apoptosis in a nontransformed gastric mucosal cell line (RGM-1). Exposure to H. pylori-activated peripheral blood mononuclear cells (PBMCs), but not H. pylori itself, induced Fas antigen (Fas Ag) expression, indicating a Fas-regulatory role for inflammatory cytokines in this system. Of various inflammatory cytokines tested, only interleukin 1beta and tumor necrosis factor alpha induced Fas Ag expression, and removal of either of these from the conditioned medium abrogated the response. When exposed to Fas ligand, RGM-1 cells treated with PBMC-conditioned medium underwent massive and rapid cell death, interestingly, with a minimal effect on total cell numbers early on. Cell cycle analysis revealed a substantial increase in S phase cells among cells exposed to Fas ligand, suggesting an increase in their proliferative response. Taken together, these data indicate that the immune environment secondary to H. pylori infection plays a critical role in priming gastric mucosal cells to undergo apoptosis or to proliferate based upon their Fas Ag status.
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486
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Dart MJ, Wasicak JT, Ryther KB, Schrimpf MR, Kim KH, Anderson DJ, Sullivan JP, Meyer MD. Structural aspects of high affinity ligands for the alpha 4 beta 2 neuronal nicotinic receptor. PHARMACEUTICA ACTA HELVETIAE 2000; 74:115-23. [PMID: 10812947 DOI: 10.1016/s0031-6865(99)00023-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) are a heterogeneous family of related ion channels that are widely distributed throughout the central and peripheral nervous systems. They all share a common architecture of five subunit proteins that combine at the cell surface to create a ligand-gated cation permeable pore. Significant effort is currently being expended by medicinal chemistry teams to synthesize ligands that exhibit selectivity for central over peripheral nAChR subtypes. Within the CNS, multiple nAChR subtypes are recognized, and the discovery of ligands exhibiting selectivity among these subtypes offers an opportunity for the development of novel therapeutic agents. The alpha 4 beta 2 subtype is one of the most abundant nAChR subtypes within the CNS, and has been the primary focus of high affinity ligand design. Nicotine (1), and more recently, epibatidine (2) have served as structural templates for the design of the majority of active compounds. Although the diversity of nAChR ligands is growing, the structural requirements necessary for high affinity binding with the alpha 4 beta 2 receptor remain poorly understood. The putative pharmacophoric elements common to all potent alpha 4 beta 2 ligands include (1) a basic or quaternized nitrogen atom, and (2) a less basic nitrogen or a carbonyl oxygen that presumably interact with electron rich and electron deficient sites on the receptor, respectively. The family of currently known high affinity analogs consists of a diverse array of azacycles containing a basic amine. Several additional basic amine fragments have been identified, including the pyrrolizidine nucleus (exemplified by 8) and the 2-azabicyclo[2.2.1]heptane skeleton (exemplified by 9). In addition, we have found that the furo[2,3-b]pyridine heterocycle (compound 10) serves as useful bioisosteric replacement for the pyridyl substituent of nicotine. A preliminary pharmacophore model is proposed in which a reasonable superposition of the putative pharmacophoric elements of the diverse array of high affinity ligands for the alpha 4 beta 2 nAChR reported herein may be accommodated.
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487
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Kim KH, Kim HJ, Kang JS, Mar W. Determination of metoprolol enantiomers in human urine by coupled achiral-chiral chromatography. J Pharm Biomed Anal 2000; 22:377-84. [PMID: 10719921 DOI: 10.1016/s0731-7085(99)00279-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Achiral chiral column switching HPLC assay was developed to allow the separation and quantitation of the enantiomers of metoprolol in human urine by means of fluorescence detection. Urine samples were prepared by liquid liquid extraction, followed by HPLC. The racemic metoprolol and internal standard were separated from the interfering components in urine and quantified on the silica column, and the enantiomers were determined on a Chiralcel OD chiral stationary phase. The two columns were connected by a switching valve equipped with a silica trap column. Detection limit was 25 ng/ml for each enantiomer. The intra-day variation ranged between 0.38 and 4.94% in relation to the measured concentration and the inter-day variation was 0.15-3.13%. It has been applied to the determination of (R)-(+)-metoprolol and (S)-(-)-metoprolol in urine from healthy volunteers dosed with racemic metoprolol tartrate.
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488
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Kim KH, Strauss EG, Strauss JH. Adaptive mutations in Sindbis virus E2 and Ross River virus E1 that allow efficient budding of chimeric viruses. J Virol 2000; 74:2663-70. [PMID: 10684281 PMCID: PMC111755 DOI: 10.1128/jvi.74.6.2663-2670.2000] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alphavirus glycoproteins E2 and E1 form a heterodimer that is required for virus assembly. We have studied adaptive mutations in E2 of Sindbis virus (SIN) and E1 of Ross River virus (RR) that allow these two glycoproteins to interact more efficiently in a chimeric virus that has SIN E2 but RR E1. These mutations include K129E, K131E, and V237F in SIN E2 and S310F and C433R in RR E1. Although RR E1 and SIN E2 will form a chimeric heterodimer, the chimeric virus is almost nonviable, producing about 10(-7) as much virus as SIN at 24 h and 10(-5) as much after 48 h. Chimeras containing one adaptive change produced 3 to 20 times more virus than did the parental chimera, whereas chimeras with two changes produced 10 to 100 times more virus and chimeras containing three mutations produced yields that were 180 to 250 times better. None of the mutations had significant effects upon the parental wild-type viruses, however. Passage of the triple variants eight or nine times resulted in variants that produced virus rapidly and were capable of producing >10(8) PFU/ml of culture fluid within 24 h. These further-adapted variants possessed one or two additional mutations, including E2-V116K, E2-S110N, or E1-T65S. The RR E1-C433R mutation was studied in more detail. This Cys is located in the putative transmembrane domain of E1 and was shown to be palmitoylated. Mutation to Arg-433 resulted in loss of palmitoylation of E1. The positively charged arginine residue within the putative transmembrane domain of E1 would be expected to alter the conformation of this domain. These results suggest that interactions within the transmembrane region are important for the assembly of the E1/E2 heterodimer, as are regions of the ectodomains possibly identified by the locations of adaptive mutations in these regions. Further, the finding that four or five changes in the chimera allow virus production that approaches the levels seen with the parental SIN and exceeds that of the parental RR illustrates that the structure and function of SIN and RR E1s have been conserved during the 50% divergence in sequence that has occurred.
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489
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Kim KH, Hwang YJ, Cho JB, Park SI. Immunization of cultured juvenile rockfish Sebastes schlegeli against Microcotyle sebastis (Monogenea). DISEASES OF AQUATIC ORGANISMS 2000; 40:29-32. [PMID: 10785860 DOI: 10.3354/dao040029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
To determine whether immunization with Microcotyle sebastis antigen could induce protection against the parasite's establishment, naive juvenile rockfish were immunized by injection or immersion with whole worm antigen of M. sebastis. The infestation intensities of immunized groups following a challenge (2 wk after boosting) with 5000 M. sebastis eyed-eggs were significantly lower than those of control groups, when determined 7 wk postinfection. The fish in the groups boosted with M. sebastis antigen showed stronger protection than unboosted groups. The control group injected with FCA only showed a significantly smaller number of worms than the control group, which was immersed in PBS containing seawater. The results strongly suggest that both specific and nonspecific immune factors participate in the protection of rockfish against M. sebastis establishment.
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490
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Braun KW, Tribley WA, Griswold MD, Kim KH. Follicle-stimulating hormone inhibits all-trans-retinoic acid-induced retinoic acid receptor alpha nuclear localization and transcriptional activation in mouse Sertoli cell lines. J Biol Chem 2000; 275:4145-51. [PMID: 10660575 DOI: 10.1074/jbc.275.6.4145] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The regulation of retinoic acid receptor alpha (RARalpha) signal transduction has not been well characterized. In this study, we determined whether all-trans-retinoic acid (tRA) and follicle-stimulating hormone (FSH) modulate RARalpha receptor subcellular localization, leading to changes in its transcriptional activity and protein expression in mouse Sertoli cell lines. We found that tRA induced the nuclear localization of RARalpha within 30 min and that longer term exposure increased the receptor transcriptional activity and RARalpha protein expression. Conversely, FSH suppressed the tRA-induced nuclear localization, transcriptional transactivation, and protein expression of RARalpha. Treatment with two different protein kinase A-selective antagonists reversed the inhibitory actions of FSH on tRA-dependent RARalpha nuclear localization and transcriptional activity. These results are consistent with the involvement of protein kinase A in mediating the inhibitory effects of FSH. For the first time, we demonstrate a unique signaling convergence between the RARalpha and the FSH-mediated signaling pathways, which may have significant implications in the testis because both are critical regulators of testis physiology.
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491
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Singh BN, Kim KH. Floating drug delivery systems: an approach to oral controlled drug delivery via gastric retention. J Control Release 2000; 63:235-59. [PMID: 10601721 DOI: 10.1016/s0168-3659(99)00204-7] [Citation(s) in RCA: 356] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In recent years scientific and technological advancements have been made in the research and development of rate-controlled oral drug delivery systems by overcoming physiological adversities, such as short gastric residence times (GRT) and unpredictable gastric emptying times (GET). Several approaches are currently utilized in the prolongation of the GRT, including floating drug delivery systems (FDDS), also known as hydrodynamically balanced systems (HBS), swelling and expanding systems, polymeric bioadhesive systems, modified-shape systems, high-density systems, and other delayed gastric emptying devices. In this review, the current technological developments of FDDS including patented delivery systems and marketed products, and their advantages and future potential for oral controlled drug delivery are discussed.
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492
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Kim KH, Sung CK, Park BK, Kim WK, Oh CW, Kim KS. Percutaneous gallbladder drainage for delayed laparoscopic cholecystectomy in patients with acute cholecystitis. Am J Surg 2000; 179:111-3. [PMID: 10773145 DOI: 10.1016/s0002-9610(00)00247-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Many studies have concluded that delayed or interval laparoscopic cholecystectomy (LC) in patients with acute cholecystitis (AC) demonstrated higher conversion rates and complication rates compared with early LC. However, if the acutely inflamed gallbladder is decompressed by emergent percutaneous gallbladder drainage (PGBD), it may decrease the technical difficulty of LC allowing successful delayed LC when the patient is in better condition. The purpose of this retrospective study was to assess the outcomes of delayed LC following PGBD in patients with AC. METHODS A total of 72 LC for AC were divided into PGBD (n = 27) and non-PGBD groups (n = 45). The PGBD group had delayed LC (after 72 hours of admission). Thirty-two non-PGBD patients had early LC (within 72 hours of admission) and 13 non-PGBD had delayed LC. Outcome of delayed LC for the PGBD group was assessed by LC time, conversion rate, morbidity rate, and hospital stay, and compared with that of the non-PGBD group. RESULTS Compared with early and delayed LC of the non-PGBD group, the PGBD group showed longer LC time (median 110 minutes versus 87.5 minutes versus 85 minutes, P <0. 05), a little lower conversion rate (15% versus 25% versus 23%), similar morbidity rate (15% versus 9% versus 15%), and prolonged hospital stay (13 days versus 7 days versus 10 days). CONCLUSIONS PGBD did not significantly improve the outcome of LC for AC as assessed by conversion and morbidity rate and hospital stay compared with no PGBD. Thus, we can conclude that although PGBD is a safe and effective emergency procedure for AC, it should be limited to higher risk groups such as elderly or critically ill patients and to acalculous cholecystitis.
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493
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Lee MW, Park MS, Jeong DW, Kim KH, Kim HH, Toh SH. Diarylheptanoids from the leaves of Alnus hirsuta Turcz. Arch Pharm Res 2000; 23:50-3. [PMID: 10728657 DOI: 10.1007/bf02976466] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Diarylheptanoids, (5S)-1,7-bis-(3,4-dihydroxyphenyl)-5-hydroxyheptane-3-one (1, hirsutanonol), (5S)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-3-one-5-O-beta-D-xylopyranosi de (2, oregonin), (5R)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-5-O-beta-D-xylopyranoside (3), and (5R)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-5-O-beta-D-glucopyranoside (4) were isolated from the leaves of Alnus hirsuta Turcz. The structures of these compounds were identified based on the spectral and physicochemical data.
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494
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Abstract
Expression of critical enzymes in fatty acid and fat biosynthesis is tightly controlled by nutritional and hormonal stimuli. The expression of fatty acid synthase, which catalyzes all reactions for synthesis of palmitate from acetyl-CoA and malonyl-CoA, and of mitochondrial glycerol-3-phosphate acyltransferase, which catalyzes the first acylation step in glycerophospholipid synthesis, is decreased to an undetectable level during fasting. Food intake, especially a high carbohydrate, fat-free diet after fasting, causes a dramatic increase in the transcription of these genes. Insulin secretion is increased during feeding and has a positive effect on expression. By using adipocytes in culture and transgenic mice that express the reporter gene driven by the fatty acid synthase promoter, the cis-acting sequence that mediates insulin regulation of the fatty acid synthase promoter was defined. Upstream stimulatory factors (USF) that bind to the -65 E-box are required for insulin-mediated transcriptional activation of the fatty acid symthase gene. Sterol regulatory element binding protein (SREBP)-1 may be also involved in induction of these genes during feeding. Using specific inhibitors and expressing various signaling molecules, we found that insulin regulation of the fatty acid synthase promoter is mediated by the phosphatidylinositol (PI)3-kinase signaling pathway and that protein kinase B/akt is a downstream effector.
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495
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Jung SM, Lee BG, Joh GY, Cha JK, Chung WT, Kim KH. Primary Sjögren's syndrome manifested as multiple sclerosis and cutaneous erythematous lesions: a case report. J Korean Med Sci 2000; 15:115-8. [PMID: 10719822 PMCID: PMC3054592 DOI: 10.3346/jkms.2000.15.1.115] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Sjögren's syndrome is a chronic autoimmune disorder characterized by lymphocytic infiltration of the lacrimal and salivary glands, leading to dryness of eyes (kerato-conjunctivitis sicca) and mouth (xerostomia). The skin lesions in Sjögren's syndrome are usually manifested as xeroderma, but sometimes appear as annular erythema or vasculitis. Central nervous system symptoms may be presented as one of extraglandular manifestations, though rare in incidence, and need differential diagnosis from multiple sclerosis. We report a case of a 45-year-old woman diagnosed as multiple sclerosis at first but later as neurologic manifestation of primary Sjögren's syndrome, showing signs of multiple sclerosis and cutaneous erythematous lesions.
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496
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Kim KH, Kim DS, Hong SP, Keon OS. Reversed-phase high performance liquid chromatographic separation of the enantiomers of terbutaline by derivatization with 2,3,4,6-tetra-o-acetyl-beta-D-glucopyranosyl isothiocyanate. Arch Pharm Res 2000; 23:26-30. [PMID: 10728652 DOI: 10.1007/bf02976461] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The enantiomers of the bronchodilator terbutaline were separated by reversed-phase high performance liquid chromatography after derivatization with 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate(GITC) reagent. The derivatization proceeded quantitatively within 1 h at room temperature. The corresponding diastereomeric thiourea derivatives were well resolved on an ODS column with acetonitrile-acetate buffer as a mobile phase. Elution orders of the diastereomers were confirmed by derivatization of R-(-)-terbutaline and S-(+)-terbutaline which were collected by semi-preparative chiral HPLC using Sumichiral OA-4700 column. The native fluorescence of terbutaline was quenched by derivatization with GITC. The detection limit was 25 ng when monitored at UV 278 nm.
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497
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Cho KH, Ahn HT, Park KC, Chung JH, Kim SW, Sung MW, Kim KH, Chung PH, Eun HC, Youn JI. Reconstruction of human hard-palate mucosal epithelium on de-epidermized dermis. J Dermatol Sci 2000; 22:117-24. [PMID: 10674825 DOI: 10.1016/s0923-1811(99)00056-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Artificial hard-palate mucosa equivalents were reconstructed using keratinocytes derived from normal human hard-palate and de-epidermized dermis. Reconstructed hard-palate mucosal epithelium formed in three-dimensional culture was compared to native hard-palate mucosal epithelium and reconstructed oral buccal mucosal epithelium with regard to keratin expression. Artificial hard-palate mucosal epithelium reconstructed in medium with delipidized serum showed a differentiation pattern similar to that of hard-palate epithelium in vivo. The present study also confirmed that keratinocytes derived from hard-palate mucosa are intrinsically different from those of nonkeratinizing oral surfaces.
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498
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Moon SJ, Ahn W, Lee MG, Kim H, Lee SI, Seo JT, Case RM, Kim KH. A novel effect of rebamipide: generation of [Ca(2+)](i) oscillations through activation of CCK(1) receptors in rat pancreatic acinar cells. Eur J Pharmacol 2000; 388:17-20. [PMID: 10657542 DOI: 10.1016/s0014-2999(99)00849-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The protective effect of 2-(4-chlorobenzoylamino)-3-[2(1H)-quinolinon-4-yl]-propionic acid (rebamipide) on gastric mucosa is well established. Here we demonstrate that rebamipide acts on pancreatic acinar cells to generate oscillations of intracellular Ca(2+) concentration ([Ca(2+)](i)) through the activation of cholecystokinin subtype 1 (CCK(1)) receptors. At concentrations higher than 5 microM, rebamipide induced [Ca(2+)](i) oscillations in individual fura-2-loaded pancreatic acinar cells. The frequency of oscillations increased with increasing concentrations of rebamipide, while the latency between stimulation of cells and initiation of [Ca(2+)](i) oscillations decreased with increasing concentration. The [Ca(2+)](i) oscillations evoked by rebamipide were inhibited by the CCK(1) receptor antagonist L-364,718 but not by atropine or the CCK(2) receptor antagonist L-365,260 indicating that rebamipide is a nonpeptide CCK(1) receptor agonist.
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499
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Choy K, Pae EK, Park Y, Kim KH, Burstone CJ. Effect of root and bone morphology on the stress distribution in the periodontal ligament. Am J Orthod Dentofacial Orthop 2000; 117:98-105. [PMID: 10629526 DOI: 10.1016/s0889-5406(00)70254-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
To achieve predictable and physiologic orthodontic tooth movement, estimating the axis of rotation of a tooth and the level and location of maximum stress distributed in the periodontal ligament is essential. An extracted upper canine was scanned into a computer 2-dimensionally and divided into 80 nodes along the long axis of the tooth. A mathematical formula was derived, and stress was calculated on each node. The purpose of this study was to reveal the center of resistance, axis of rotation, and an ideal force magnitude associated with various periodontal conditions, such as potential root resorption, alveolar bone loss, and varying anatomic root shape by analyzing the stress distribution in the periodontal ligament. The study demonstrates that the location of center of resistance changes significantly with variation of shape and length of the root embedded in alveolar bone. In contrast, in response to alveolar bone loss, the relative location of the center of resistance to total root length remains constant. Analysis of the stress distribution pattern in our 2-dimensional model reveals that the relationship between location of force and axis of rotation is determined by s(2) (that is) a constant depends on shape and length of a root in alveolar bone. Tapered and short roots that result from alveolar bone loss or apical root resorption are prone to tipping. The optimal orthodontic force may vary depending on the maximum stress in the periodontal ligament.
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500
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Ro JY, Lee BC, Kim JY, Chung YJ, Chung MH, Lee SK, Jo TH, Kim KH, Park YI. Inhibitory mechanism of aloe single component (alprogen) on mediator release in guinea pig lung mast cells activated with specific antigen-antibody reactions. J Pharmacol Exp Ther 2000; 292:114-21. [PMID: 10604937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
We previously reported that the glycoprotein extracted from aloe strongly inhibited the mediator releases caused by the activation of guinea pig lung mast cells. Therefore, this study aimed to purify a single component that has an antiallergic effect from crude aloe extract and then to assess the effects of aloe single component (alprogen) on the mechanism of mediator releases caused by the mast cell activation. We purified aloe extracts by using various columns. We also purified mast cells from guinea pig lung tissues by using enzyme digestion, rough and discontinuous density Percoll gradient. Mast cells were sensitized with IgG(1) (anti-ovalbumin) and challenged with ovalbumin. Histamine was assayed by using a fluorometric analyzer and leukotrienes by radioimmunoassay. [Ca(2+)](i) level was analyzed by using a confocal laser scanning microscope. Protein kinase activity was determined by the protein phosphorylated with [gamma-(32)P]ATP. The phospholipase D activity was assessed by the labeled phosphatidylalcohol. The amount of mass 1,2-diacylglycerol (DAG) was measured by the [(3)H]DAG produced when prelabeled with [(3)H]myristic acid. Phospholipase A(2) activity was determined by measuring the lyso-phosphatidylcholine released from the labeled phospholipids. Alprogen significantly decreased histamine and leukotriene releases and blocked completely Ca(2+) influx during mast cell activation. The protein kinase C and phospholipase D activities were decreased by alprogen in dose-dependent manner. Alprogen inhibited mass DAG formation and the phospholipase A(2) activity during mast cell activation. The data suggest that alprogen purified from aloe inhibits multiple signals as well as blocking Ca(2+) influx caused by mast cells activated with specific antigen-antibody reactions and that then the inhibition of histamine and leukotriene release follows.
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