• Journal of The Korean Society of Clinical Toxicology
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• v.20 no.2
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• pp.39-44
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• 2022

N-Acetylcysteine (NAC) is the standard antidote treatment for preventing hepatotoxicity caused by acetaminophen (AAP) poisoning. This review summarizes the recent evidence for the treatment of AAP poisoning. Several alternative intravenous regimens of NAC have been suggested to improve patient safety by reducing adverse drug reactions and medication errors. A two-bag NAC infusion regimen (200 mg/kg over 4 h, followed by 100 mg/kg over 16 h) is reported to have similar efficacy with significantly reduced adverse reactions compared to the traditional 3-bag regimen. Massive AAP poisoning due to high concentrations (more than 300-lines in the nomogram) needs to be managed with an increased maintenance dose of NAC. In addition to NAC, the combination therapy of hemodialysis and fomepizole is advocated for severe AAP poisoning cases. In the case of a patient presenting with an altered mental status, metabolic acidosis, elevated lactate, and an AAP concentration greater than 900 mg/L, hemodialysis is recommended even if NAC is used. Fomepizole decreases the generation of toxic metabolites by inhibiting CYP2E1 and may be considered an off-label use by experienced clinicians. Since the nomogram cannot be applied to sustained-release AAP formulations, all potentially toxic sustained-release AAP overdoses should receive a full course of NAC regimen. In case of ingesting less than the toxic dose, the AAP concentration is tested twice at an interval of 4 h or more; NAC should be administered if either value is above the 150-line of the nomogram.

• Environmental Mutagens and Carcinogens
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• v.26 no.3
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• pp.77-85
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• 2006

2,3,7,8-Tetrachlorodibenzo-$\rho$-dioxin(TCDD) displays high toxicity in animals and has been implicated in human carcinogenesis. Although TCDD is recognized as potent carcinogens, relatively little is known about their role in the tumor promotion and carcinogenesis. It is known that TCDD can increase of cancer risk from various types of tissue by a mechanism possibly involving the aryl hydrocarbon receptor (AhR) activation. In this study, effects of TCDD on cellular proliferation of normal human skin and lung fibroblasts, Detroit551 and WI38 cells were investigated. In addition, to enhance our understanding of TCDD-mediated carcinogenesis, we have investigated process in which expression of Erk1/2, cyclinD1, oncogene such as Ha-ras and c-myc, and their cognate signaling pathway. TCDD that are potent activators of AhR-mediated activity was found to induce significant increase of cytochrome P4501A1 mRNA expression, suggesting a presence of functional AhR. These results support that CYP1A1 enzyme may be involved in the generation of TCDD-induced toxicity. Moreover mitogen-activated protein kinases (MARKs) phosphorylation and cyclin D1 overexpression are induced by TCDD, which corresponded with the progression of cellular proliferation. However, TCDD did not affected Ha-ras and c-myc mRNA expression. Taken together, it seems that TCDD are could be a part of cellular proliferation in non-tumorigenic normal human cells such as Detroit551 and WI38 cells through the upregulation of MAPKs signaling pathway regulating growth of cell population. Therefore, AhR-activating TCDD could potentially contribute to tumor promotion and Detroit551 and WI38 cells have been used as a detection system of tumorigenic effects of TCDD.

• Preventive Nutrition and Food Science
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• v.16 no.3
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• pp.242-247
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• 2011

The methanolic extract of Rosa davurica Pall. roots exhibited strong antioxidant activity in a 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assay and was found to be a dose-dependent inhibitor of non-enzymatic formation of advanced glycation end products (AGEs), which are relevant to diabetes complications. HPLC-diode array detector (DAD) analysis of the R. davurica Pall. root extract led to the identification of four compounds: hydrocaffeic acid, catechin, epicatechin, and ellagic acid. Catechin was present in the largest amount and exhibited high antiglycation activity. A CYP3A4 assay was used to investigate potential interactions between drugs and the extract, and results suggest that the R. davurica Pall. root extract had moderate potential for interfering with drug metabolism. The R. davurica Pall. extract did not display anti-inflammatory activity on the level of that for tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in a lipopolysaccharide (LPS)-stimulated macrophage assay; however, the extract did exhibit low to moderate immunostimulatory activity in a pro-inflammatory macrophage assay. Therefore, we conclude that R. davurica Pall. root is a promising anti-AGE agent with low to moderate risks of associated inflammation or drug interaction.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.1
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• pp.15-24
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• 2003

The purpose of this study is to investigate the sterilization effect of Er:YAG laser against the intraoral acid producing bacterium, S. mutans, by irradiating the culture solution containing S. mutans KCTC 3065 with Er:YAG laser having a $650{\mu}m$ diameter beam through the non-contact method. We obtained the following results after examining the temperature changes of the culture solution, numbers of bacterial colonies, and acid-producing ability and attaching ability on teeth by measuring the amount of extracellular polysaccharide produced by S. mutans. The number of bacterial colony was decreased in $10{\mu}l$ culture solution irradiated with laser in overall compared to the control solution. The number decreased as the irradiation intensity and pulse repetition rate were larger and as the exposure time was increased. However, it did not change significantly in $100{\mu}l$ culture solution compared to the control solution. Although the acid-producing ability of S. mutans was inhibited for a certain duration after laser irradiation in 10r1 bacterial culture solution, it did not change in $100{\mu}m$ solution compared with the control solution. The amount of extracellular polysaccharide synthesized by S. mutans was partially decreased through laser irradiation in $10{\mu}m$ culture solution but did not change in $100{\mu}m$ culture solution. Based on these findings, we concluded that Er:YAG laser has an sterilization effect on S. mutans in which we presume that the mechanism is through the heat effect rather than the mechanical effect from development of ultrasound.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.11-18
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• 2004

The eruption of permanent teeth represents the movement in the alveolar bone before appearance in oral cavity, to the occlusal plane after appearance in oral cavity, and additive movement after reaching th the occlusal plane. Tooth eruption is mostly controlled by genetic signals. The eruption stage is divided to preeruptive alveolar stage, alveolar bone stage, mucosal stage according to the process of growth and development. If the disturbance is occured in any stage of eruption, tooth does not erupt. The cause of eruption disturbance are ectopic position of the tooth germ, obstruction of the eruption path and defects in the follicle or PDL. In the treatment of eruption disturbance, surgical procedures are commonly used. There are three kind of surgical procedure ; surgical exposure, surgical repositioning, surgical exposure and traction Surgical exposure is basic procedure. This involves removal of mucosa, bone, lesion that are surrounding the teeth, dental sac when necessary to maintain a patent channel between the crown and the normal eruptive path into the oral cavity. To ensure this patency, many techniques including cementation of a celluloid crown, packing with gutta-percha or zinc oxide-eugenol, or a surgical pack, are used. When surgical exposure is conducted, operators should not expose any part of cervical root cement and not injure periodontium or root of adjunct tooth. After surgical exposure, tooth should be surrounded by keratinized gingiva. There is direct relationship between the extent of development of pathophysiologic aberrations and the intensity of the manipulative injury inflicted on the tooth by surgical treatment, so operator should consider this thing. In these cases, surgical exposure is conducted on Maxillary 1st milars that have a eruption disturbance and improve the eruption disturbance effectively.

• Clinical and Experimental Pediatrics
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• v.54 no.3
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• pp.137-140
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• 2011

Testicular adrenal rest tumors (TARTs) are considered to be formed from aberrant adrenal tissue that has become hyperplastic because of elevated adrenocorticotropic hormone (ACTH) in male patients with congenital adrenal hyperplasia (CAH). A 6-year-old boy presented with testicular enlargement and pubic hair. He was diagnosed with CAH complicated by precocious puberty. However, he was not followed-up. At the age of 17, he visited the outpatient clinic because of testicular enlargement and short stature. His right and left testicles were $10{\times}6$ cm and $7.5{\times}4.5$ cm, respectively. His height was 155.1 cm (standard deviation score (SDS), -2.90). The diagnosis of CAH due to 21 hydroxylase deficiency was confirmed by mutation analysis of CYP21A2. Histological examination of the testes showed large, polygonal, eosinophilic cells with round nuclei and prominent nucleoli, which were suggestive of TARTs. He was treated with dexamethasone for 3 weeks and tumors regressed. Subsequently, dexamethasone was replaced by prednisolone and $9{\alpha}$-fludrocortisone; thereafter, the reduced testis size has been maintained.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.350-364
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• 1999

The distribution of mast cells and nerves were investigated in the submandibular and sublingual glands of postnatal rats, using morphometric, histochemical and immunohistochemical techniques. Mast cells were observed in the submandibular and sublingual glands of postnatal development. Number of mast cells gradually increased in both glands following development. At birth, mast cells were relatively fewer in submandibular gland than those in sublingual gland, and they were mainly distributed in parenchymal tissues. At $2{\sim}4$ weeks, most of the mast cells were observed in the connective tissues, surrounding neurovascular elements, but some mast cells were closely related with the acini of submandibular gland. PGP 9.5 immunoreactive nerve fibers were found in the submandibular and sublingual glands of all developmental age. The nerve fibers were showed in varicose shape, and mainly located in adjacent area of ducts and vascular components of both glands. The number of nerve fibers were increased rapidly until 8 weeks, but they were not increased any more until 24 weeks. Therefore, it is suggested that mast cells and nerve fibers related with each other, and that their interactions may play roles not only in maturation of secretory units but also growth and differentiation of the tubular structures of the rat submandibular and sublingual glands during postnatal development.

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1287-1292
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• 2005

KR-33028 (N-[4-cyano-benzo[b]thiophene-2-carbonyl]guanidine) is a new cardioprotective agent for preventing ischemia-reperfusion injury. This study was performed to identify the metabolic pathway of KR-33028 in human liver microsomes and to compare its metabolism with that of cryopreserved human hepatocytes. Human liver microsomal incubation of KR-33028 in the presence of NADPH and UDPGA resulted in the formation of four metabolites, M1, M2, M3, and M4. M1 and M2 were identified as 5-hydroxy-KR-33028 and 7-hydroxy-KR-33028, respectively, on the basis of LC/MS/MS analysis with the synthesized authentic standard. M3 and M4 were suggested to be dihydroxy-KR-33028 and hydroxy-KR-33028-glucuronide, respectively. Metabolism of KR-33028 in cryopreserved human hepatocytes resulted in the formation of M1, M2, and M4. These data show a good correlation between major metabolites formed in human liver microsomes and cryopreserved human hepatocytes. In addition, KR­33028 was found to inhibit moderately the metabolism of CYP1A2 substrates. Based on the results obtained metabolic pathway of KR-33028 is proposed.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.551-557
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• 2007

This paper describes a study on the permeability reduction of the riverbed ground during urban railway tunnel construction. The research is mainly concentrated on the study of the grouting or injection methods among permeability reduction methods which can be adapted in the riverbed ground. Firstly, the various grouting methods are theoretically reviewed and compared based on the previous research papers and case study results. It is also evaluated the grouting methods in view of a safe construction of the river crossing railway tunnel. Baced on the literature review and previous construction data, the design technology of grouting methods considering the long term hydro-geological behaviour in the riverbed, is suggested. Two injection methods namely, Natural Durable Stabilizer(N.D.S) and Space-Multi Injaction Grouting(S.M.I) methods, are introduced as new approach methods which can be adopted to modify the riverbed ground. In order to evaluate the ground that grouted and modified by the N.D.S and S.M.I method, the pilot test programmes including the field and laboratory permeability tests, are carried out in the river crossing tunnel construction sites. The results obtained from pilot test programme, are also reviewed. In conclusion, the grouting efficiency of the S.M.I method using the non-alcalimeter silica sol is better than that of NDS method using cement. In addition, it hopes that the research results are contributed to develop the grouting design technology.

• Korean Journal of Ichthyology
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• v.24 no.2
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• pp.118-124
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• 2012

The present study was conducted to investigate different gene expression profile between treated poMSTNpro and non-treated in rainbow trout and to identify those genes that are specifically or predominantly expressed in treated poMSTNpro by employing annealing control primer (ACP)-based GeneFishing polymerase chain reaction (PCR). We isolated total RNAs in muscle tissues from the treated poMSTNpro fish by immersion bath technique with fish myostatin prodomain (Paralichthys olivaceus, poMSTNpro) for one month and the other was non-treated poMSTNpro, and synthesized cDNA using annealing control primers (ACP, Seegene, Korea). Using 20 different ACPs for PCR, were cloned sequenced, and analyzed identities of 2 differentially expressed genes (DEGs). According to BLAST analysis, sequences of 2 clones significantly matched database entries and confirmed by semi-quantitative RT-PCR. The functional roles of one up-regulated gene, cytochrome P450 mono-oxygenases 2K1v2 (CYP2K1v2), and one down-regulated gene was Profilin-1 were identified. We identified distinctive gene expression profiles in improved rainbow trout growth by treatment with a fish myostatin prodomain using ACP-based GeneFishing.