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Jung J, Choe PG, Choi S, Kim E, Lee HY, Kang CK, Lee J, Park WB, Lee S, Kim NJ, Choi EH, Oh M. Reduction in the acquisition rate of carbapenem-resistant Acinetobacter baumannii (CRAB) after room privatization in an intensive care unit. J Hosp Infect 2021; 121:14-21. [PMID: 34929231 DOI: 10.1016/j.jhin.2021.12.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 12/08/2021] [Accepted: 12/12/2021] [Indexed: 11/17/2022]
Abstract
BACKGROUND Acinetobacter baumannii is one of the major pathogens responsible for healthcare-associated infections, especially in intensive care units (ICUs). AIM To evaluate the effect of room privatization in an ICU on the acquisition of carbapenem-resistant A. baumannii (CRAB). METHODS Between March and August 2017, a medical ICU was renovated from a multibed bay room to single rooms. Acquisition of CRAB was compared between patients admitted to the ICU over 18 months pre-renovation (September 2015 to February 2017) and post-renovation (September 2017 to February 2019). A Cox proportional hazard model was used with adjustment for demographics and comorbidities. FINDINGS Of the 901 patients, who contributed 8,276 patient-days, 95 (10.5%) acquired CRAB during their ICU stay. The CRAB acquisition rate was significantly higher during the pre-renovation period (1.87 per 100 patient-days) than during the post-renovation period (0.39 per 100 patient-days) (P < 0.001). In the multivariable Cox regression model, CRAB acquisition was significantly associated with the presence of a feeding tube (adjusted hazard ratio [aHR], 6.08; 95% confidence interval [CI], 2.46-15.06; P < 0.001), continuous renal replacement therapy (aHR, 1.66; 95% CI, 1.09-2.53; P = 0.019) and admission after renovation of the ICU to single rooms (aHR, 0.23; 95% CI, 0.12-0.41; P < 0.001). CONCLUSIONS Renovation of ICUs to single rooms is an efficient strategy to prevent transmission of multidrug-resistant organisms and hospital-acquired infections.
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Affiliation(s)
- J Jung
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - P G Choe
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea.
| | - S Choi
- Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea
| | - E Kim
- Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea
| | - H Y Lee
- Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea
| | - C K Kang
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea
| | - J Lee
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - W B Park
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea
| | - S Lee
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - N J Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea
| | - E H Choi
- Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea; Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - M Oh
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Center for Infection Control and Prevention, Seoul National University Hospital, Seoul, Republic of Korea
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Ki H, Lee Y, Choi EH, Lee S, Ihee H. SVD-aided non-orthogonal decomposition (SANOD) method to exploit prior knowledge of spectral components in the analysis of time-resolved data. Struct Dyn 2019; 6:024303. [PMID: 30931347 PMCID: PMC6435371 DOI: 10.1063/1.5085864] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 03/11/2019] [Indexed: 06/09/2023]
Abstract
Analysis of time-resolved data typically involves discriminating noise against the signal and extracting time-independent components and their time-dependent contributions. Singular value decomposition (SVD) serves this purpose well, but the extracted time-independent components are not necessarily the physically meaningful spectra directly representing the actual dynamic or kinetic processes but rather a mathematically orthogonal set necessary for constituting the physically meaningful spectra. Converting the orthogonal components into physically meaningful spectra requires subsequent posterior analyses such as linear combination fitting (LCF) and global fitting (GF), which takes advantage of prior knowledge about the data but requires that all components are known or satisfactory components are guessed. Since in general not all components are known, they have to be guessed and tested via trial and error. In this work, we introduce a method, which is termed SVD-aided Non-Orthogonal Decomposition (SANOD), to circumvent trial and error. The key concept of SANOD is to combine the orthogonal components from SVD with the known prior knowledge to fill in the gap of the unknown signal components and to use them for LCF. We demonstrate the usefulness of SANOD via applications to a variety of cases.
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Affiliation(s)
- H. Ki
- Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, South Korea
| | | | | | | | - H. Ihee
- Author to whom correspondence should be addressed:
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Yoon NY, Wang HY, Jun M, Jung M, Kim DH, Lee NR, Hong KW, Seo SJ, Choi E, Lee J, Lee H, Choi EH. Simultaneous detection of barrier- and immune-related gene variations in patients with atopic dermatitis by reverse blot hybridization assay. Clin Exp Dermatol 2018; 43:430-436. [PMID: 29380403 DOI: 10.1111/ced.13367] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2017] [Indexed: 01/06/2023]
Abstract
BACKGROUND Hereditary factors are involved in the pathogenesis of atopic dermatitis (AD). However, AD-related gene variations are significantly different across ethnicities. AIM To identify mutations and single-nucleotide polymorphisms (SNPs) in barrier- or immune-related genes from Korean patients with AD and compare the variations with those observed in nonatopic healthy controls (HCs), and to use novel reverse blot hybridization assay (REBA) for AD-related gene variants. METHODS We carried out REBA to simultaneously detect variations in genes related to barrier or immune function, namely, FLG, SPINK5, KLK7, DEFB1, TNFα, KDR, FCER1A, IL4, IL5,IL5RA, IL9, IL10, IL12, IL12R, IL13 and IL18, from Korean patients with AD, and compared the variation to that in nonatopic healthy controls. RESULTS The homozygous mutants of KLK7 and SPINK5-2475, and the heterozygous mutants of FLG 3321delA, SPINK5-1156, DEFB1, KDR, IL5RA, IL9 and IL12RB1 were significantly more frequent in AD. It has been predicted that the larger the number of gene variants, the higher the odds ratio of AD prevalence; however, we did not find any significant correlation between the number of gene variants and AD severity. CONCLUSION Using REBA, we identified more genetic variants that can predict AD occurrence. We also verified that REBA can be used to easily and accurately detect multiple AD-related gene variants simultaneously. In addition, we identified a correlation between KLK7 mutation and AD in Koreans, which is the first such report, to our knowledge.
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Affiliation(s)
- N Y Yoon
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - H Y Wang
- M&D, Inc., Wonju Eco Environmental Technology Center, Wonju, Republic of Korea
| | - M Jun
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - M Jung
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - D H Kim
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - N R Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - K-W Hong
- TheragenEtex Bio Institute, Suwon, Republic of Korea
| | - S J Seo
- Department of Dermatology, Chung-Ang University Hospital, Seoul, Republic of Korea
| | - E Choi
- Institute of Lifestyle Medicine, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - J Lee
- Department of Biomedical Laboratory Science, Yonsei University College of Health Sciences, Wonju, Republic of Korea
| | - H Lee
- Department of Biomedical Laboratory Science, Yonsei University College of Health Sciences, Wonju, Republic of Korea
| | - E H Choi
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
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Kwon HS, Lee JH, Kim GM, Choi EH, Bae JM. Topical evening primrose oil as a possible therapeutic alternative in children with molluscum contagiosum. Clin Exp Dermatol 2017; 42:923-925. [PMID: 28940438 DOI: 10.1111/ced.13226] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2017] [Indexed: 11/28/2022]
Affiliation(s)
- H S Kwon
- Department of Dermatology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, 93 Jungbu-daero, Paldal-gu, Suwon, 16247, Korea
| | - J H Lee
- Department of Dermatology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, 93 Jungbu-daero, Paldal-gu, Suwon, 16247, Korea
| | - G M Kim
- Department of Dermatology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, 93 Jungbu-daero, Paldal-gu, Suwon, 16247, Korea
| | - E H Choi
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - J M Bae
- Department of Dermatology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, 93 Jungbu-daero, Paldal-gu, Suwon, 16247, Korea
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Cha YS, Kim H, Lee Y, Choi EH, Kim HI, Kim OH, Cha KC, Lee KH, Hwang SO. The relationship between serum ammonia level and neurologic complications in patients with acute glufosinate ammonium poisoning: A prospective observational study. Hum Exp Toxicol 2017; 37:571-579. [DOI: 10.1177/0960327117715902] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Glufosinate ammonium poisoning can cause neurological complications even after a symptom-free period. We prospectively investigated the predictors of neurologic complications in acute glufosinate ammonium poisoning and the change of serum ammonia level as a predictor of patient’s presence and recovery of neurologic complication. This prospective observational study collected data from consecutive patients diagnosed with acute glufosinate ammonium poisoning between September 2014 and June 2016. Serum ammonia was serially measured. The patients were divided into two groups: the neurologic complication group and the nonneurologic complication group. We also defined 25 other insecticide- or herbicide-poisoned patients as controls. The neurologic complication group included 18 patients (72.0%). The latency period for neurologic complications was within 48-h postingestion. The peak ammonia level was statistically higher in the neurologic complication group than in the control group ( p < 0.001) and the nonneurologic complication groups ( p = 0.001). There was a statistical difference between the nonneurologic complication group and the neurologic complication group ( p = 0.0085) in terms of ingested amount. The peak ammonia was the only predictor for the development of neurologic complications (the optimal cutoff: 90 μg/dL). In patients with mental changes, the mean serum ammonia levels before and after recovery of the mental changes were statistically different ( p = 0.0019). In acute glufosinate ammonium poisoning, serial serum ammonia level measurements are needed and a serum peak ammonia level greater than 90 μg/dL is a predictor of neurologic complications. Also, it is important to treat the hyperammonemia in acute glufosinate ammonium poisoning.
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Affiliation(s)
- YS Cha
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - H Kim
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - Y Lee
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - EH Choi
- Biostatistician, Institute of Lifestyle Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - HI Kim
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - OH Kim
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - K-C Cha
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - KH Lee
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
| | - SO Hwang
- Department of Emergency Medicine, Yonsei University, Wonju College of Medicine, Wonju, Republic of Korea
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Park SY, Kim BK, Wang HY, Kim SH, Kim HJ, Lee HY, Choi EH. PCR-reverse blot hybridization assay for fast and accurate identification of causative species in superficial fungal infections. Clin Exp Dermatol 2016; 41:359-65. [DOI: 10.1111/ced.12797] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2015] [Indexed: 11/27/2022]
Affiliation(s)
- S. Y. Park
- Department of Dermatology; Yonsei University Wonju College of Medicine; Wonju Korea
| | - B. K. Kim
- Department of Dermatology; Yonsei University Wonju College of Medicine; Wonju Korea
| | - H. Y. Wang
- M&D, Inc.; Wonju Eco Environmental Technology Center; Wonju Korea
| | - S. H. Kim
- Department of Clinical Laboratory Science; College of Health Sciences; Catholic University of Pusan; Busan Korea
| | - H. J. Kim
- Department of Biomedical Laboratory Science; College of Health Sciences; Yonsei University; Wonju Korea
| | - H. Y. Lee
- Department of Biomedical Laboratory Science; College of Health Sciences; Yonsei University; Wonju Korea
| | - E. H. Choi
- Department of Dermatology; Yonsei University Wonju College of Medicine; Wonju Korea
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Kim EJ, Choi EH, Kim NJ, Oh BR, Lim JH. The effect of surveillance program for surgical site infection of hepato-biliary-pancreatic surgery for 5 years: a prospective study in a tertiary hospital in Korea. Antimicrob Resist Infect Control 2015. [PMCID: PMC4474658 DOI: 10.1186/2047-2994-4-s1-p76] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Oyungerel B, Lim H, Lee CH, Choi EH, Li GH, Choi KD. Anti-inflammatory Effects of Magnolia sieboldii Extract in Lipopolysaccharide-Stimulated RAW264.7 Macrophages. TROP J PHARM RES 2014. [DOI: 10.4314/tjpr.v12i6.8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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9
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Kim JJ, Choi IK, Choi EH, Kim JG, Moon DG, Kang MK, Lee JM, Shin DI, Kim CJ, Seung KB. Impact of diabetes mellitus on long term clinical outcome in patients with acute myocardial infarction undergoing percutaneous coronary intervention. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.p3093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Panngom K, Baik KY, Nam MK, Han JH, Rhim H, Choi EH. Preferential killing of human lung cancer cell lines with mitochondrial dysfunction by nonthermal dielectric barrier discharge plasma. Cell Death Dis 2013; 4:e642. [PMID: 23703387 PMCID: PMC3674375 DOI: 10.1038/cddis.2013.168] [Citation(s) in RCA: 161] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The distinctive cellular and mitochondrial dysfunctions of two human lung cancer cell lines (H460 and HCC1588) from two human lung normal cell lines (MRC5 and L132) have been studied by dielectric barrier discharge (DBD) plasma treatment. This cytotoxicity is exposure time-dependent, which is strongly mediated by the large amount of H2O2 and NOx in culture media generated by DBD nonthermal plasma. It is found that the cell number of lung cancer cells has been reduced more than that of the lung normal cells. The mitochondrial vulnerability to reactive species in H460 may induce distinctively selective responses. Differential mitochondrial membrane potential decrease, mitochondrial enzymatic dysfunction, and mitochondrial morphological alteration are exhibited in two cell lines. These results suggest the nonthermal plasma treatment as an efficacious modality in lung cancer therapy.
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Affiliation(s)
- K Panngom
- Department of Plasma Bioscience and Display, Kwangwoon University, Seoul, Republic of Korea
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Oh BR, Song JS, Choi EH, Noh HK, Choe PG. P226: An engaged intervention to decrease central line-asssociated infections in the ICU. Antimicrob Resist Infect Control 2013. [PMCID: PMC3687756 DOI: 10.1186/2047-2994-2-s1-p226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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12
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Kim JH, Park HY, Jung M, Choi EH. Automicroneedle therapy system combined with topical tretinoin shows better regenerative effects compared with each individual treatment. Clin Exp Dermatol 2012; 38:57-65. [DOI: 10.1111/j.1365-2230.2012.04405.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
A double-stranded RNA plasmid which confers the superkiller phenotype was transferred into a wine yeast (Montrachet strain 522) and its leucine-requiring derivative (strain 694) by cytoduction, using the protoplast fusion technique. The killer wine yeast constructed completely suppressed the growth of killer-sensitive strains of Saccharomyces cerevisiae in yeast extract-peptone-glucose medium at pH 4.5, whereas the killer effect was somewhat decreased at pH 3.5. The wine yeast harboring the killer factor also inhibited the growth of killer-sensitive cells satisfactorily when it was grown in grape juice.
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Affiliation(s)
- T Seki
- University of California, Davis, California 95616
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14
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Hong SP, Oh Y, Jung M, Lee S, Jeon H, Cho MY, Lee SH, Choi EH. Topical calcitriol restores the impairment of epidermal permeability and antimicrobial barriers induced by corticosteroids. Br J Dermatol 2010; 162:1251-60. [PMID: 20302580 DOI: 10.1111/j.1365-2133.2010.09760.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The active form of vitamin D(3) , calcitriol, is widely used for the treatment of psoriasis, with or without topical corticosteroids. Topical corticosteroids are known to disrupt permeability and antimicrobial barriers, even with short-term use. Yet, the effect of topical calcitriol on epidermal permeability and antimicrobial barriers disrupted by topical corticosteroids has not been determined. OBJECTIVES To examine the effect of calcitriol on epidermal permeability and antimicrobial barrier function that has been impaired by corticosteroids, as well as to elucidate the mechanism of improvement. MATERIAL AND METHODS Topical calcitriol or the control vehicle was applied to each flank of hairless mice 20 min after treatment with topical clobetasol propionate and repeated every 12 h for 3·5 days. Barrier function assessment, Nile red staining, electron microscopy, immunohistochemistry, Western blotting, and real-time reverse transcriptase-polymerase chain reaction studies were performed 24 h after the last application. RESULTS Epidermis co-treated with topical calcitriol showed an improvement of stratum corneum integrity and barrier recovery, more intense fluorescence staining with Nile red, and an increase in lamellar body (LB) maturation and density, as well as upregulation of major epidermal lipid synthesis-related enzymes (3-hydroxy-3-methylglutaryl-CoA, serine-palmitoyl transferase and fatty acid synthase), mouse beta-defensin 3, cathelin-related antimicrobial peptide and vitamin D receptor. CONCLUSIONS We found that topical calcitriol restored both the epidermal permeability and antimicrobial barrier that had been impaired by corticosteroids. This restoration was mediated by both an activation of the cutaneous vitamin D pathway and an increase of epidermal lipids and antimicrobial peptides, promoted by the formation of the LB and the activity of epidermal lipid synthesis-related enzymes.
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Affiliation(s)
- S P Hong
- Department of Dermatology, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea
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Bikle DD, Chang S, Crumrine D, Elalieh H, Man MQ, Choi EH, Dardenne O, Xie Z, Arnaud RS, Feingold K, Elias PM. 25 Hydroxyvitamin D 1 alpha-hydroxylase is required for optimal epidermal differentiation and permeability barrier homeostasis. J Invest Dermatol 2004; 122:984-92. [PMID: 15102089 DOI: 10.1111/j.0022-202x.2004.22424.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Keratinocytes express high levels of 25OHD 1alpha-hydroxylase (1OHase). The product of this enzyme, 1,25-dihydroxyvitamin D (1,25(OH)(2)D), promotes the differentiation of keratinocytes in vitro suggesting an important role for this enzyme in epidermal differentiation. To test whether 1OHase activity is essential for keratinocyte differentiation in vivo we examined the differentiation process in mice null for the expression of the 1alphaOHase gene (1alphaOHase(-/-)). Heterozygotes for the null allele were bred, and the progeny genotyped by PCR. The epidermis of the 1alphaOHase(-/-) animals and their wild-type littermates (1alphaOHase(+/+)) were examined by histology at the light and electron microscopic level, by immunocytochemistry for markers of differentiation, and by function examining the permeability barrier using transepidermal water loss (TEWL). No gross epidermal phenotype was observed; however, immunocytochemical assessment of the epidermis revealed a reduction in involucrin, filaggrin, and loricrin-markers of differentiation in the keratinocyte and critical for the formation of the cornified envelope. These observations were confirmed at the electron microscopic level, which showed a reduction in the F (containing filaggrin) and L (containing loricrin) granules and a reduced calcium gradient. The functional significance of these observations was tested using TEWL to evaluate the permeability barrier function of the epidermis. Although TEWL was normal in the basal state, following disruption of the barrier using tape stripping, the 1alphaOHase(-/-) animals displayed a markedly delayed recovery of normal barrier function. This delay was associated with a reduction in lamellar body secretion and a failure to reform the epidermal calcium gradient. Thus, the 25OHD 1OHase is essential for normal epidermal differentiation, most likely by producing the vitamin D metabolite, 1,25(OH)(2)D, responsible for inducing the proteins regulating calcium levels in the epidermis that are critical for the generation and maintenance of the barrier.
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Affiliation(s)
- D D Bikle
- Department of Medicine, Veterans Affairs Medical Center and University of California, San Francisco 94121, USA.
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Park BD, Youm JK, Jeong SK, Choi EH, Ahn SK, Lee SH. The characterization of molecular organization of multilamellar emulsions containing pseudoceramide and type III synthetic ceramide. J Invest Dermatol 2003; 121:794-801. [PMID: 14632198 DOI: 10.1046/j.1523-1747.2003.12470.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
To investigate the molecular organization and phase behavior of physiologic lipid mixtures that contain either newly synthesized pseudoceramide or type III synthetic ceramide, various analytical techniques were used. The phase transition temperatures detected in differential scanning calorimetry analysis were 51.19 and 50.52 for the pseudoceramide-containing physiologic lipid mixture and synthetic type III ceramide-containing lipid mixture, respectively. From the small angle XRD patterns, the multilamellar emulsion-pseudoceramide showed 11.5 nm and 7.61 nm lamellar phases, while the multilamellar emulsion-synthetic ceramide showed only a 7.61 nm lamellar phase. The nonceramide containing lipid mixture did not show any distinct repeat pattern. Lateral packing distances of multilamellar emulsion-pseudoceramide and multilamellar emulsion-synthetic ceramide were measured as 0.4119 and 0.4110 nm at 30, respectively, which indicated the presence of hexagonal lattice. On the contrary, non-multilamellar emulsion did not show any definite repeat pattern. Transmission electron microscopy observation showed nearly comparable lamellar structures in all of the tested emulsions compared to the structure of human stratum corneum intercellular lipid. Decrease of water contents resulted in phase transition into liquid phase for all the tested emulsions, whereas phase transition into orthorhombic phase was observed only in multilamellar emulsion-pseudoceramide. From these results, we concluded that the molecular organization of multilamellar emulsion-pseudoceramide was characterized as the lateral hexagonal phase and both the long and short periodicity lamellar phases, which showed structural similarity with the native human stratum corneum intercellular lipid.
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Affiliation(s)
- B D Park
- NeoPharm Co., Ltd, Taejeon, Korea
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Abstract
BACKGROUND Many elderly people have chronic xerosis, and frequently experience an exacerbation during winter. OBJECTIVES To investigate the barrier state of aged murine skin with or without barrier disruption in a dry environment. METHODS Aged and young hairless mice were kept separately in dry and normal conditions for 9 days. Acetone treatment was used to perturb the skin barrier. Skin barrier function was measured as transepidermal water loss (TEWL), and morphological changes in the epidermis were studied by electron microscopy. RESULTS The baseline TEWL was not higher in the dry environment. The number of stratum corneum (SC) layers and the epidermal thickness of aged mice increased in the dry environment. The recovery rate of the aged skin barrier was neither accelerated nor delayed in the dry environment. In the normal environment, aged mice recovered more slowly than young mice. After barrier perturbation in the aged mice, changes in SC layers and in epidermal thickness were similar in the two environments. The secretion and number of lamellar bodies did not differ between the two environments. CONCLUSIONS We confirmed that a dry environment induces epidermal proliferation and scaling in both aged and young mice. However, no remarkable difference was found in the skin barrier recovery of aged hairless mice in a dry environment.
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Affiliation(s)
- E H Choi
- Department of Dermatology, Yonsei University, Wonju College of Medicine, Wonju, Korea
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18
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Kim YB, Choi EH, Keum G, Kang SB, Lee DH, Koh HY, Kim Y. An efficient synthesis of morpholin-2-one derivatives using glycolaldehyde dimer by the Ugi multicomponent reaction. Org Lett 2001; 3:4149-52. [PMID: 11784164 DOI: 10.1021/ol016716w] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new one-pot procedure for the efficient synthesis of novel 3-substituted morpholin-2-one-5-carboxamide derivatives using commercially available glycolaldehyde dimer as a bifunctional component with various alpha-amino acids and isocyanides by the Ugi five-center three-component reaction (U-5C-3CR) was developed. [reaction: see text]
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Affiliation(s)
- Y B Kim
- Biochemicals Research Center, Korea Institute of Science and Technology, Seoul, 130-650, Korea
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Pai H, Lee HJ, Choi EH, Kim J, Jacoby GA. Evolution of TEM-related extended-spectrum beta-lactamases in Korea. Antimicrob Agents Chemother 2001; 45:3651-3. [PMID: 11709362 PMCID: PMC90891 DOI: 10.1128/aac.45.12.3651-3653.2001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2001] [Accepted: 08/21/2001] [Indexed: 11/20/2022] Open
Abstract
TEM-52, differing from TEM-1 by having the substitutions Glu-104-->Lys, Met-182-->Thr, and Gly-238-->Ser, has previously been described as the most prevalent extended-spectrum beta-lactamase (ESBL) in Korea. In a further survey, we discovered the ESBLs TEM-15, which is like TEM-52 but lacks the substitution at residue 182, and TEM-88, which is like TEM-52 with an additional Gly-196-->Asp substitution. TEM-88 retained the activity of TEM-52 against moxalactam. Otherwise, the kinetic properties of the three ESBLs failed to show an advantage to this evolution.
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Affiliation(s)
- H Pai
- Department of Internal Medicine, College of Medicine, Dankook University, Chonan, Korea
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20
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Abstract
The generation of a draft sequence of the human genome has spawned a unique opportunity to investigate the role of genetic variation in human diseases. The difference between any two human genomes has been estimated to be less than 0.1% overall, but still, this means that there are at least several million nucleotide differences per individual. The study of single nucleotide polymorphisms (SNPs), the most common type of variant, is likely to contribute substantially to deciphering genetic determinants of common and rare diseases. The effort to identify SNPs has been accelerated by three developments: the availability of sequence data from the genome project, improved informatic tools for searching the former and high-throughput genotype platforms. With these new tools in hand, dissecting the genetics of disease will rapidly move forward, although a number of formidable challenges will have to be met to see its promise realized in clinical medicine.
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Affiliation(s)
- J G Taylor
- Section of Genomic Variation, Pediatric Oncology Branch, National Cancer Institute, Advanced Technology Center, 8717 Grovemont Circle, Gaithersburg, MD 20877, USA
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Whang SW, Lee SH, Elias PM, Feingold KR, Choi EH, Ahn SK. Intralesional steroids reduce inflammation from extravasated chemotherapeutic agents. Br J Dermatol 2001; 145:680-2. [PMID: 11703309 DOI: 10.1046/j.1365-2133.2001.04439.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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22
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Pai H, Choi EH, Lee HJ, Hong JY, Jacoby GA. Identification of CTX-M-14 extended-spectrum beta-lactamase in clinical isolates of Shigella sonnei, Escherichia coli, and Klebsiella pneumoniae in Korea. J Clin Microbiol 2001; 39:3747-9. [PMID: 11574608 PMCID: PMC88424 DOI: 10.1128/jcm.39.10.3747-3749.2001] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
CTX-M-14 beta-lactamase was identified in a stool isolate of Shigella sonnei and in blood isolates of Escherichia coli (one isolate) and Klebsiella pneumoniae (two isolates) from different parts of Korea. The amino acid sequence differed by one amino acid from CTX-M-9 (Ala-231--> Val) and was identical to that of beta-lactamases recently found in China and Japan.
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Affiliation(s)
- H Pai
- Department of Internal Medicine, Dankook University College of Medicine, Chonan, Korea
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23
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Abstract
The purpose of this study was to identify the potential projection errors of lateral cephalometric radiographs due to head rotation in the vertical Z-axis. For this investigation, 17 human dry skull samples with permanent dentition were collected from the Department of Anatomy in the College of Medicine, Chosun University. They had no gross asymmetry and were well preserved. Each dry skull was rotated from 0 degrees to +/- 15 degrees at 1 degrees intervals. A vertical axis, the Z-axis, was used as a rotational axis to have 527 lateral cephalometric radiographs exposed. The findings were that: (1) angular measurements have fewer projection errors than linear measurements; (2) the greater the number of landmarks on the midsagittal plane that are included in angular measurements, the fewer the projection errors occurring; (3) horizontal linear measurements decrease gradually in length as the rotational angle toward the film increases, whereas a small increase and then decrease of the length occurs as the rotational angle toward the focal spot increases; (4) horizontal linear measurements have more projection errors than vertical linear measurements according to head rotation; and (5) projection errors of vertical linear measurements increase as the distance from the rotational axis increases. In summary, angular measurements of lateral cephalometric radiographs are more useful than linear measurements in minimizing the projection errors associated with head rotation on a vertical axis.
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Affiliation(s)
- Y J Yoon
- Department of Orthodontics, College of Dentistry, Chosun University, Gwang-Ju, Korea.
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Chun HS, Kim HJ, Choi EH. Modulation of cytochrome P4501-mediated bioactivation of benzo[a]pyrene by volatile allyl sulfides in human hepatoma cells. Biosci Biotechnol Biochem 2001; 65:2205-12. [PMID: 11758911 DOI: 10.1271/bbb.65.2205] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Allyl sulfides such as diallyl sulfide (DAS), diallyl disulfide (DADS), and diallyl trisulfide (DATS), typical flavor components of Allium vegetables, have been shown to inhibit benzo[a]pyrene (B[a]P)-induced carcinogenesis in animal models. As a possible mechanism of this inhibition, the effect of these volatile substances on cytochrome P450 (CYP)1 (CYP1A1, 1A2 and 1B1)-mediated bioactivation of B[a]P was investigated using a human hepatoma cell model (HepG2). DADS and DATS inhibited the B[a]P-induced ethoxyresorufin O-deethylase (EROD) activity, a marker enzyme for CYP1, by 30-90% and 70-95% at 100-1,000 microM concentration, respectively. The cell viability, an indicator of the capacity to inhibit B[a]P bioactivation, was increased by treatments of 100-1,000 microM DADS and 10-100 microM DATS. Immunoblot results indicated that the B[a]P inducible CYP1A2 protein was suppressed by 100-1,000 microM of DADS and 10-100 microM of DATS, but CYP1A1 and 1B1 were not detectable in any microsomes. Analysis of B[a]P metabolites revealed that the level of 7,8-diol formed was significantly reduced in the DADS and DATS treated microsomes as compared to the control. The level of 9,10-diol and 4,5-diol formed was also lowered by the allyl sulfide treatments. These results suggest that the protective mechanism of allyl sulfides on B[a]P-induced carcinogenesis is possibly related with the modulation of CYP1-mediated bioactivation of B[a]P.
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Affiliation(s)
- H S Chun
- Korea Food Research Institute, Sungnam.
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25
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Choi EH, Zimmerman PA, Foster CB, Zhu S, Kumaraswami V, Nutman TB, Chanock SJ. Genetic polymorphisms in molecules of innate immunity and susceptibility to infection with Wuchereria bancrofti in South India. Genes Immun 2001; 2:248-53. [PMID: 11528516 DOI: 10.1038/sj.gene.6363767] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2000] [Revised: 04/19/2001] [Accepted: 04/19/2001] [Indexed: 11/08/2022]
Abstract
A pilot study was conducted to determine if host genetic factors influence susceptibility and outcomes in human filariasis. Using the candidate gene approach, a well-characterized population in South India was studied using common polymorphisms in six genes (CHIT1, MPO, NRAMP, CYBA, NCF2, and MBL2). A total of 216 individuals from South India were genotyped; 67 normal (N), 63 asymptomatic microfilaria positive (MF+), 50 with chronic lymphatic dysfunction/elephantiasis (CP), and 36 tropical pulmonary eosinophilia (TPE). An association was observed between the HH variant CHIT1 genotype, which correlates with decreased activity and levels of chitotriosidase and susceptibility to filarial infection (MF+ and CP; P = 0.013). The heterozygosity of CHIT1 gene was over-represented in the normal individuals (P = 0.034). The XX genotype of the promoter region in MBL2 was associated with susceptibility to filariasis (P = 0.0093). Since analysis for MBL-sufficient vs insufficient haplotypes was not informative, it is possible the MBL2 promoter association results from linkage disequilibrium with neighboring loci. We have identified two polymorphisms, CHIT1 and MBL2 that are associated with susceptibility to human filarial infection, findings that merit further follow-up in a larger study.
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Affiliation(s)
- E H Choi
- Immunocompromised Host Section, Pediatric Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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26
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Lee IW, Ahn SK, Choi EH, Whang KK, Lee SH. Complications of eyelash and eyebrow tattooing: reports of 2 cases of pigment fanning. Cutis 2001; 68:53-5. [PMID: 11480149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
Eyelash and eyebrow tattooing are commonly performed procedures that have a very low rate of reported complications. We describe one case of infraorbital pigmentation after eyelash tattooing and another of periorbital pigmentation after eyebrow tattooing. Although most complications related to eyelash and eyebrow tattooing, including pigment fanning, have been reported by ophthalmologists, pigment fanning is also of concern to dermatologists.
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Affiliation(s)
- I W Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, 162 Ilsan-Dong, Wonju, 220-701, Korea
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Ahn SK, Jiang SJ, Hwang SM, Choi EH, Lee JS, Lee SH. Functional and structural changes of the epidermal barrier induced by various types of insults in hairless mice. Arch Dermatol Res 2001; 293:308-18. [PMID: 11480591 DOI: 10.1007/s004030100226] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Acute barrier disruption, regardless of the method of induction, depletes the stratum corneum intercellular lipids and this stimulates a series of lipid/ DNA synthesis activities which lead to barrier recovery. After barrier disruption by tape stripping, occlusion with a water vapor-impermeable membrane inhibits barrier repair. In this study, we investigated the changes in the murine epidermis after barrier perturbation by tape stripping and three different types of surfactants (Emalex NP-12, ENP-12; sodium dodecyl sulfate, SDS; benzalkonium chloride, BKC). To examine the effect of an artificial barrier, we covered the animals with a water vapor-impermeable membrane for 3 days following barrier disruption and then exposed them to the air for 2 days. The histological findings after occlusion or air exposure were similar. However, after air exposure for 2 days, the thickness of the epidermis including the stratum corneum and the stratum granulosum layers decreased to about half that of the epidermis after occlusion. Ultrastructural examination revealed obvious distortion of the lamellar bilayers within the stratum corneum interstices immediately after barrier disruption. After 3 days of occlusion, extensive disorganization was evident in the intercellular domain of the stratum corneum, whereas 2 days after removal of the occlusion, the normal basic unit structure of the lamellar bilayers had partially reappeared. Our findings provide evidence that the kinetic pattern of barrier repair and the morphological changes are similar after occlusion following barrier disruption regardless of the mechanism of disruption.
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Affiliation(s)
- S K Ahn
- Department of Dermatology, Yonsei University Wonju College of Medicine, Korea
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Hong JY, Lee HJ, Piedra PA, Choi EH, Park KH, Koh YY, Kim WS. Lower respiratory tract infections due to adenovirus in hospitalized Korean children: epidemiology, clinical features, and prognosis. Clin Infect Dis 2001; 32:1423-9. [PMID: 11317242 DOI: 10.1086/320146] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2000] [Revised: 09/18/2000] [Indexed: 02/04/2023] Open
Abstract
On occasion, outbreaks of infection with adenovirus types 3, 7, and 21 cause severe lower respiratory tract infections (LRTIs) in children. From 1990 to 1998, all cases of LRTI due to adenovirus at the Seoul National University Children's Hospital, Seoul, Korea, were reviewed. Adenoviruses were recovered from nasal aspirate specimens of 87 (5.9%) of 1472 children with LRTI. The principal adenovirus serotypes were type 2 (13 [15%] of 87 strains), type 3 (13 [15%]), and type 7 (36 [41%]). Of the 87 infections, 62 (71%) occurred in children <2 years of age, and 81 (94%) occurred in children <5 years of age. Infections due to types 3 and 7 occurred during epidemics, whereas infections due to type 2 occurred sporadically. For patients who were infected with types 3 and 7, extrapulmonary abnormalities were more common and homogeneous consolidation and pleural effusion were frequently identified on radiographs. The mortality rate was 12% overall and 19% among patients who were infected with type 7. Residual sequelae were identified in 6 (50%) of 12 patients who were infected with type 3 and in 9 (25%) of 36 who were infected with type 7. The data confirm that adenovirus types 3 and 7 can cause epidemics of severe LRTI in young children. Epidemics of LRTIs caused by adenovirus types 3 and 7 in Korea have not been described in reports published elsewhere.
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Affiliation(s)
- J Y Hong
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
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Abstract
In our previous study, we concluded that an epidural blockade combined with intravenous acyclovir is very effective in treating the acute pain in herpes zoster and postherpetic neuralgia. We evaluated the efficacy of oral famciclovir and epidural blockade on the pain of herpes zoster, compared to acyclovir administered intravenously and epidural blockade. For this purpose, we examined a new group treated with famciclovir and epidural blockade to compare with the group treated with acyclovir and epidural blockade in our previously study. The changes in the intensity of pain, the number of days required for relief of pain, and the total duration of pain were checked. We compared the days required for relief of pain (DRP) and the total duration of pain (TDP) of this group with those of the previous studied group treated with acyclovir and epidural blockade. DRP was significantly less, but TDP was similar. DRP and TDP were significantly lower, if the patients were treated within 7 days of symptom onset. The patients had a shorter DRP regardless of pain type than the previously studied group treated with acycolvir and epidural blockade. For the severe and moderate pain grades, there was a shorter DRP from 100 to 10. TDP was not significantly different for the groups regardless of pain type or grade. We believe that famciclovir and epidural blockade are very effective in treating the pain of herpes zoster, with a view to shortening the period of acute pain, providing similar effects on the prevention of postherpetic neuralgia, and being convenient to administer, compared to intravenous acyclovir and epidural blockade in our previous study.
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Affiliation(s)
- H J Ahn
- Department of Dermatology, Yonsei University Wonju College of Medicine, 162 Ilsan-Dong, Wonju, Kangwon-Do 220-701, Republic of Korea
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30
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Abstract
BACKGROUND Although occlusive dressings have great potential in the management of psoriasis vulgaris, the therapeutic mechanism is not completely understood. Occlusion artificially restores and corrects the defective barrier in psoriasis plaques. Additionally, occlusion is know to normalize the epidermal calcium gradients in hyperproliferative murine skin models. METHODS To investigate the basis of the therapeutic effect of occlusion on psoriatic plaques, we investigated the ultrastructural morphology of intercorneocyte lipid layers, lamellar bodies, and calcium gradient in chronic plaque-type psoriasis after occlusion with a water vapor-impermeable membrane. The specimens were processed for electron microscopy using: (i) ruthenium tetroxide postfixation; and (ii) ion-capture cytochemistry for calcium localization. RESULTS Occlusion for 7 days resulted in a nearly mature pattern of intercellular multilamellar structures, re-establishment of the near-normal epidermal calcium gradient, and disappearance of calcium precipitates from the stratum corneum interstices. CONCLUSIONS The normalization of the permeability barrier and epidermal calcium gradient may play important roles in the therapeutic effects of occlusive dressings in chronic plaque-type psoriasis.
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Affiliation(s)
- S M Hwang
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, South Korea
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31
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Abstract
BACKGROUND alpha-hydroxyacids (AHA), such as glycolic acid and lactic acid, have recently been used in cosmetic and dermatological formulations. However, the mechanisms of action of these substances have not been well documented. OBJECTIVES This study was done to investigate the effects of AHA on the skin barrier of hairless mice and to clarify the contribution of AHA to the formation and secretion of the lamellar bodies (LB), which are known to be the critical structure for barrier function in the epidermis. METHODS 5% Lactic acid and 5% glycolic acid were applied to normal skin of the mice daily for 14 days. RESULTS Changes in transepidermal water loss (TEWL), capacitance and electron microscopic findings of the epidermis of hairless mice were compared with those in which only the vehicle was applied. CONCLUSIONS There were no significant differences in TEWL, capacitance or epidermal thickness between the epidermis of the mice to which AHA or vehicle only had been applied. On electron micrographs, the normal epidermis to which AHA had been applied showed an increase in the number and secretion of LB and a decrease in the number of stratum corneum (SC) layers in comparison with the epidermis to which the vehicle only had been applied. The lipid layers of the SC intercellular spaces and calcium gradient in both the epidermis with application of AHA and that with vehicle only were normal. These results suggest that AHA, in low concentration (5%), may improve the skin barrier in hairless mice by inducing enhanced desquamation, and by increasing the number and secretion of LB without increasing TEWL.
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Affiliation(s)
- T H Kim
- Department of Dermatology, Yonsei University, Wonju College of Medicine, Wonju, 162 Ilsan-dong, Wonju, Korea 220-701
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Choi EH, Lee HJ. Genetic diversity and molecular epidemiology of the G protein of subgroups A and B of respiratory syncytial viruses isolated over 9 consecutive epidemics in Korea. J Infect Dis 2000; 181:1547-56. [PMID: 10823752 DOI: 10.1086/315468] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/1999] [Revised: 02/14/2000] [Indexed: 11/04/2022] Open
Abstract
To study genetic variation and molecular epidemiology of the G protein of respiratory syncytial virus (RSV), 253 strains from a children's hospital in Korea over 9 consecutive epidemics were analyzed. Restriction analysis of the entire G protein gene demonstrated 24 genotypes among 188 subgroup A and 6 among 65 subgroup B isolates. Two to 4 dominant genotypes of subgroup A cocirculated, and different genotypes predominated in each epidemic. Predominant genotypes were replaced with new genotypes during consecutive epidemics. One of 2 dominant genotypes among subgroup B predominated alternately or concurrently. Phylogenetic analysis revealed that there were multiple lineages, with clustering related to their location and time of isolation among strains from Korea and worldwide. Geographic and temporal distinction have been shown more clearly for subgroup B than subgroup A. These results suggest that the G protein of RSV is continuously evolving, with a distinct pattern presumably due to immune selection in a localized region over time.
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Affiliation(s)
- E H Choi
- Immunocompromised Host Section, Pediatric Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
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Abstract
We report a case of cutaneous tuberculosis presenting as cellulitis. The patient was a 63-year-old Korean woman who also had diabetes mellitus and a 20-year-history of oral corticosteroid medication prescribed for arthralgia. In addition, she had had pulmonary tuberculosis 20-year previously for which she received systemic treatment for 1 year. Her clinical cellulitis failed to respond to antibiotic therapy. Subsequent investigations, using histopathology and polymerase chain reaction, established an alternative diagnosis of cutaneous tuberculosis. The skin eruption cleared after treatment with isoniazid, rifampicin, ethambutol and pyrazinamide. This case represents a most unusual presentation of tuberculosis in the skin. The atypical features may reflect the patient's general medical state.
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Affiliation(s)
- N H Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
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Kim BH, Sung SR, Choi EH, Kim YI, Kim KJ, Dong SH, Kim HJ, Chang YW, Lee JI, Chang R. Dedifferentiation of conditionally immortalized hepatocytes with long-term in vitro passage. Exp Mol Med 2000; 32:29-37. [PMID: 10762059 DOI: 10.1038/emm.2000.6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The rat hepatocytes were immortalized using a temperature-sensitive mutant of SV40 large T antigen (tsT) to develop as a possible substitute for primary hepatocytes. Four rat hepatocyte lines that have been developed and maintained more than passage 50, were characterized for their cellular morphology, T antigen and p53 expression, chromosomes, liver-specific differentiation, telomerase activity and anchorage independent growth. All of four cell lines showed a typical epithelial cell morphology, but the population-doubling time became short with passage: 18 to 60%. T antigen expression was increased with passage about 3 to 65 times at permissive temperature but decreased significantly at non-permissive temperature. The expression level of p53 unchanged during passages was also decreased at non-permissive temperature. The distribution of chromosome number changed somewhat with passage. The production levels of albumin and urea in four cell lines were 2.4 to 13.0% and 7.5 to 19.9% of those produced in primary hepatocytes, respectively and were decreased to an undetectable level with passage. Telomerase activity was increased 10 fold following immortalization of cells, but anchorage independent growth of cells did not develop. These results indicate that conditionally immortalized hepatocytes become dedifferentiated with in vitro passage, which may be caused by marked chromosomal damages that occur with compulsive and continuous replications by the increment of T antigen content with passage and its sequential inhibition of p53 function.
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Affiliation(s)
- B H Kim
- Department of Internal Medicine, Kyung Hee University College of Medicine, Seoul, Korea.
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Jiang SJ, Hwang SM, Choi EH, Elias PM, Ahn SK, Lee SH. Structural and functional effects of oleic acid and iontophoresis on hairless mouse stratum corneum. J Invest Dermatol 2000; 114:64-70. [PMID: 10620117 DOI: 10.1046/j.1523-1747.2000.00834.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this study was to assess the effects of chemical and electrical modes of percutaneous penetration enhancement on the intercellular lipid lamellae of the stratum corneum. Hairless mice were treated with either oleic acid/propylene glycol and iontophoresis separately or together. Permeability barrier function was evaluated by measuring transepidermal water loss and correlated with the structure of stratum corneum intercellular lamellae, as evaluated by electron microscopy, using ruthenium tetroxide postfixation. Transepidermal water loss levels did not change following 1 h iontophoresis alone. In contrast, topical applications of 0.3 M oleic acid in propylene glycol for 1 h increased transepidermal water loss significantly. Moreover, the combined use of iontophoresis plus 0.3 M oleic acid for 1 h further increased transepidermal water loss at equivalent time points. Ultrastructural observations demonstrated both marked disorganization of the intercellular lipid lamellae, as well as the presence of distended lacunae within the stratum corneum in oleic acid/propylene glycol plus or minus iontophoresis-treated stratum corneum. This study provides direct evidence that the oleic acid/propylene glycol system can disrupt the stratum corneum lipid lamellar structures, and that coapplications of oleic acid with iontophoresis further enhance the effects of oleic acid. The synergy between chemical and physical enhancement may afford a new approach to promote transdermal drug delivery.
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Affiliation(s)
- S J Jiang
- Department of Dermatology, Yonsei University Wonju College of Medicine,Wonju, Korea
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36
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Abstract
Three female patients affected by intradermal vascular tumors were presented. The lesions were acquired and developed from preexisting port-wine stains (PWS). Among the three patients observed, two had a pyogenic granuloma (PG) and the third patients had tufted angiomas. As reported earlier, formation of a PG within the lesion of a PWS supports the assumption that arteriovenous anastomoses are associated with its pathogenesis. Occurrence of tufted angioma from a PWS, as well as coexisting but separate PWS has been reported. However, the tufted angiomas of our patient were located in different sites, one in the PWS and others separate from the PWS. This has never previously been reported.
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Affiliation(s)
- T H Kim
- Department of Dermatology, Yonsei University, Wonju College of Medicine, Korea
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Choi EH, Lee SH, Ahn SK, Hwang SM. The pretreatment effect of chemical skin penetration enhancers in transdermal drug delivery using iontophoresis. Skin Pharmacol Appl Skin Physiol 1999; 12:326-35. [PMID: 10545829 DOI: 10.1159/000029894] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The transdermal drug delivery (TDD) system has largely been divided into physical, biochemical and chemical methods. Recently, combinations of these methods were introduced for more effective delivery with less side effects. We performed this study to identify the effectiveness and mechanism of TDD using the physical method, 'iontophoresis', plus the chemical method, 'pretreatment with chemical enhancer'. The action sites of chemical enhancers in the stratum corneum (SC) were observed by electron microscope. We also studied whether this combined method synergistically impaired the skin barrier. To confirm the synergistic effect on skin penetration by this combined method, we measured the blood glucose level after insulin iontophoresis following a chemical enhancer pretreatment in rabbits. The results were that (1) dilatation of the intercellular lipid layers of the SC and lacunae was prominent in pretreatment with chemical enhancers inducing high transepidermal water loss (TEWL); (2) the skin barrier impairment, with repeated treatments showing an increased TEWL and also epidermal proliferation, was increased with the chemical enhancers that showed a high TEWL immediately after treatment; (3) the combination of chemical enhancer pretreatment and iontophoresis showed no synergistic impairment of the skin barrier, and (4) the chemical enhancer pretreatment with greater impairment of the skin barrier could increase the delivery of insulin by iontophoresis. The results showed that a combination of chemical enhancer pretreatment and iontophoresis could deliver drugs more effectively than iontophoresis alone. Our proposed theory is that iontophoretic drug delivery may be easier through the dilated intercellular spaces of the SC which have a lower electrical impedance following the chemical enhancer pretreatment. Because the effect and the side effects in the combination are decided by the chemical enhancer rather than iontophoresis, the development of proper chemical enhancers is important in future plans.
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Affiliation(s)
- E H Choi
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea.
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Abstract
OBJECTIVE To evaluate the relief of acute pain and possible preventive effects on postherpetic neuralgia through the use of an epidural blockade in the acute stage of herpes zoster. DESIGN Prospective, nonrandomized, comparative clinical trial. SETTING A dermatologic clinic in a university hospital. PATIENTS Sixty-five consecutive patients with pain due to acute herpes zoster were treated for a 7-day hospitalization period from July 1, 1996, through June 30, 1997. INTERVENTION The consecutive patients were divided into 2 groups. Group A consisted of 30 patients who were seen from July 1, 1996, through December 31, 1996, and who were treated with intravenous acyclovir (5 mg/kg) for 7 days. Group B consisted of 35 patients who were seen from January 1, 1997, through June 30, 1997, and who were treated with intravenous acyclovir (5 mg/kg) and an epidural blockade for 7 days. The changes in the intensity of pain and the total duration of pain in both groups were assessed for 12 to 18 months. MAIN OUTCOME MEASURES The number of days required for relief of pain and the total duration of pain. RESULTS The mean +/- SD number of days required for relief of pain, which was rated on a scale of 100 (worst pain) to 0 (no pain), was significantly fewer in group B than in group A: it took 2.6 +/- 1.1 days to go from 100 to 50 on the relief-of-pain scale in group B, but 3.8 +/- 1.1 days in group A (P = .03), and 12.5 +/- 6.4 days to go from 100 to 10 in group B, but 20.1 +/- 14.6 days in group A (P = .04). The duration of late residual pain was significantly shorter in group B (5.9 +/- 5.8 days) than in group A (11.9 +/- 7.5 days) (P = .03). The total duration of pain was also significantly shorter in group B (18.5 +/- 9.3 days) than in group A (31.6 +/- 17.6 days) (P = .04). CONCLUSIONS We believe that an epidural blockade combined with an antiviral agent is a very effective treatment modality for the pain of acute herpes zoster, and we recommend its use for the prevention of postherpetic neuralgia, with a view to shortening the total duration of pain, especially late residual pain.
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Affiliation(s)
- S M Hwang
- Department of Dermatology, Yonsei University Wonju College of Medicine, South Korea
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Ahn SK, Hwang SM, Jiang SJ, Choi EH, Lee SH. The changes of epidermal calcium gradient and transitional cells after prolonged occlusion following tape stripping in the murine epidermis. J Invest Dermatol 1999; 113:189-95. [PMID: 10469302 DOI: 10.1046/j.1523-1747.1999.00650.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Disruption of the epidermal permeability barrier causes an immediate loss of the calcium gradient, and barrier recovery is parallel with the restoration of the calcium gradient in the epidermis. Artificial restoration of the barrier function by occlusion with a water vapor-impermeable membrane abrogate the expected increase in lipid synthesis and retard the barrier recovery, as well as block the normalization of the epidermal calcium gradient. To clarify the long-term effects of occlusion after acute barrier perturbation, we studied the calcium distribution and epidermal keratinocytes response after occlusion with a water vapor-impermeable membrane immediately following tape stripping in the murine epidermis. Acute barrier disruption caused an immediate depletion of most calcium ions in the upper epidermis, obliterating the normal calcium gradient. When the skin barrier function was artificially corrected by occlusion, the return of calcium ions to the epidermis was blocked. After 2 h of air exposure or occlusion, the density of epidermal calcium precipitates remained negligible. The transitional cell layers appeared with occlusion, but not or negligibly with air exposure. By 6 h though, calcium precipitates could be seen, the density of the calcium precipitates with occlusion was more sparse than with air exposure. With the air exposure, the thickness of the stratum corneum had normalized and the calcium gradient nearly recovered to normal after 24 h. The longer the occlusion period, the greater was the increase of transitional cells. By 60 h of occlusion, the thickness of the stratum corneum had increased and the transitional cell layers had disappeared, in parallel with the calcium gradient which was almost normalized. These results show that prolonged occlusion of tape-stripped epidermis induced transitional cells and delayed the restoration of the epidermal calcium gradient, the stratum corneum was then restored, transitional cells having disappeared, in parallel with normalization of the epidermal calcium gradient.
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Affiliation(s)
- S K Ahn
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
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40
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Kang YC, Choi EH, Hwang SM, Lee WS, Lee SH, Ahn SK. Acne mechanica due to an orthopedic crutch. Cutis 1999; 64:97-8. [PMID: 10467500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Acne mechanica describes local irritation due to the skin being pressured, occluded, rubbed, squeezed, stretched, or heated. Examples of various physical traumas that provoke lesions in acne patients are given. Users of orthopedic crutches are at particular risk for such conditions. A crutch is another extrinsic factor to be added to the list of causes of acne mechanica.
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Affiliation(s)
- Y C Kang
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
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41
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Abstract
Pre-Sézary syndrome is an erythroderma with a chronic course, clinical findings of Sézary syndrome, lymphocytic subepidermal band infiltration at times, and repeated cycles of circulating Sézary cells of less than 1,000 cells/mm3. Duration of the pre-existing skin diseases preceding pre-Sézary erythroderma varies from a few weeks to 20 years. Before the erythroderma develops, these patients are diagnosed with contact dermatitis, neurodermatitis, chronic dermatitis, atopic dermatitis, or asteatotic eczema. Hand lesion also precedes the pre-Sézary erythroderma. This condition has been controlled by three cycles of chemotherapy consisting of vincristine, cytoxan, doxorubicin, and prednisolone. We describe a case of pre-Sézary syndrome preceded by hand lesion and treated with chemotherapy.
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Affiliation(s)
- N H Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
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42
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Lee IW, Ahn SK, Lee SH, Choi EH. Leukemic macrocheilia associated with chronic lymphocytic leukemia. Cutis 1999; 64:46-8. [PMID: 10431673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Specific cutaneous infiltrates in chronic lymphocytic leukemia presenting as a tumor or a large nodule on the face, scalp, and upper trunk are rare; involvement of the oral mucosa is extremely rare. We report a case of leukemic macrocheilia that occurred three years before a diagnosis of chronic lymphocytic leukemia was made.
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Affiliation(s)
- I W Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, Korea
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44
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Abstract
We report a 54-year-old male patient who developed an unusual form of generalized drug eruption. He had pain and breathlessness on the left chest wall. He had history of taking several drugs at private clinics under a diagnosis of herpes zoster. Two weeks later he had a generalized skin eruption. Examination showed multiple variable sized, mild pruritic, erythematous macules and papules on the face and upper extremities. Skin lesions take the form of a clinically consistent with disseminated superficial actinic porokeratosis (DSAP). Methylprednisolone 16 mg, astemisole 10 mg, oxatomide 60 mg was prescribed. Topical corticosteroid cream was applied. Within two months, his eruption had cleared almost completely. The pathogenetic mechanisms of this case are unclear, but drug and UV light have been considered.
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Affiliation(s)
- S M Hwang
- Department of Dermatology Yonsei University, Wonju College of Medicine, Kangwon-Do, Korea
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46
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Abstract
BACKGROUND Traction alopecia associated with the nurse's cap is a relatively common form of occupational hair loss. METHODS We examined 199 healthy South Korean nurses to assess the clinical and pathologic characteristics of traction alopecia caused by prolonged traction exerted at the point of attachment of the nurse's cap. RESULTS Seven nurses (3.5% of 199) had hair loss at the pin site used to secure the nurse's cap. The lesions were exclusively localized on the parieto-occipital scalp. Histopathologic findings revealed characteristic cicatricial changes which showed a marked decrease in the number of hair follicles without inflammation. CONCLUSIONS Nurse's cap alopecia is not an uncommon occupational alopecia, and appears to be a distinct clinical entity which should be distinguished from other forms of patchy alopecia.
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Affiliation(s)
- S M Hwang
- Department of Dermatology, Yonsei University, Wonju College of Medicine, South Korea
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47
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Abstract
Lyme disease is a vector-borne infection, primarily transmitted by Ixodes ticks, and caused by Borrelia burgdorferi. It has a wide distribution in the northern hemisphere. In Korea, however, only one human case has been reported, although B. burgdorferi was isolated from the vector tick I. persulcatus in the region. A 60-year-old male and a 45-year-old female developed the clinical sign of erythema migrans. Each patients were bitten by a tick four weeks and five weeks, respectively, before entering the hospital. On serologic examination, significantly increased IgM and IgG antibody titers to B. burgdorferi were observed in consecutive tests performed at an interval of two weeks. They responded well to treatment with tetracycline.
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Affiliation(s)
- T H Kim
- Department of Dermatology, Yonsei University, Wonju College of Medicine, Korea
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Lee SH, Choi EH, Feingold KR, Jiang S, Ahn SK. Iontophoresis itself on hairless mouse skin induces the loss of the epidermal calcium gradient without skin barrier impairment. J Invest Dermatol 1998; 111:39-43. [PMID: 9665384 DOI: 10.1046/j.1523-1747.1998.00226.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Iontophoresis increases the delivery of drugs across the stratum corneum, but the pathway by which ionized drugs transit the stratum corneum is unknown. In this study we examined the effect of iontophoresis on the skin barrier and the epidermal calcium gradient. Hairless mice were subjected to iontophoresis for 5-120 min and skin specimens were prepared for electron microscopy. Neither positive nor negative iontophoresis affected transepidermal water loss. Lacunar dilatation and partial distention of the intercellular layers of the stratum corneum were observed in rough proportion to applied time in iontophoresis skin as well as control skin. Additionally, using calcium capture cytochemistry, we demonstrated that both positive and negative iontophoresis caused the disappearance of the epidermal calcium gradient with marked decrease in calcium content in the upper epidermis. Positive iontophoresis was associated with increased calcium in the stratum basale and dermis, whereas negative iontophoresis increased calcium in the stratum corneum. Moreover, as previously shown after barrier disruption and sonophoresis, the decrease in calcium content in the upper epidermis was associated with an increase in lamellar body secretion and the build up of lamellar material at the stratum corneum-stratum granulosum interface. In conclusion, iontophoresis on the skin of hairless mice may induce the change of ionized molecules in the epidermis, as the loss of the calcium gradient, which causes the decrease of skin impedence, gives charged drugs the ability to cross the skin more easily. Also, the structural changes, such as lacunar dilatation, whether they result from hydration or occlusion, may help the transport of charged drugs across the stratum corneum.
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Affiliation(s)
- S H Lee
- Department of Dermatology, Yonsei University College of Medicine, Seoul, Korea
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Abstract
One hundred six cases of invasive pneumococcal infections diagnosed from 1985 to 1996 were analyzed retrospectively. The types of infection were bacteremia without focus (45%), meningitis (19%), peritonitis (17%), pneumonia (bacteremic) (16%), and others (3%). Penicillin-nonsusceptible Streptococcus pneumoniae was first detected in 1989, and its incidence increased rapidly thereafter, reaching 89% in 1995. Initial empirical regimens were of parenteral beta-lactam antimicrobials with or without an aminoglycoside, but these were modified subsequently. Among the 72 nonmeningeal infections analyzed, a favorable response at 72 hours and death were observed in 83% and 2.5%, respectively, of 40 penicillin-susceptible infections, as compared with 86% (P = 1.0) and 7.1% (P = .45) of 14 infections due to intermediate strains and 61% (P = .07) and 11% (P = .22) of 18 due to resistant strains. The favorable-response rate and mortality among 49 patients not in initially critical condition were 92% and zero, respectively, as compared with 52% (P = .00027) and 17% (P = .008) of 23 in critical condition. The data suggest that clinical outcome of penicillin-nonsusceptible pneumococcal infection outside the CNS may be more closely related to clinical condition at presentation than to the level of resistance of the causative strain when such infection is treated with parenteral beta-lactams.
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Affiliation(s)
- E H Choi
- Department of Pediatrics, Seoul National University College of Medicine, Korea
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