1.A mutation in QRDR in the ParC subunit of topoisomerase IV was responsible for fluoroquinolone resistance in clinical isolates of Streptococcus pneumoniae.
Haeryung CHOI ; Hoan Jong LEE ; Yeonhee LEE
Yonsei Medical Journal 1998;39(6):541-545
Forty-one strains of Streptococcus pneumoniae were isolated at Seoul National University Children's Hospital from 1991 to 1997. Isolates were divided into six groups based on MICs of three quinolones, ciprofloxacin, ofloxacin and norfloxacin. Sequencing showed that the isolates which were intermediately resistant to three quinolones or resistant to at least one kind of quinolone had one missense mutation, Lys137-->Asn(AAG-->AAT) substitution in the ParC subunit of topoisomerase IV without additional mutation in QRDR of the GyrA subunit of DNA gyrase. In conclusion, the ParC subunit of DNA topoisomerase IV is the primary target site for fluoroquinolone in S. pneumoniae and Lys137-->Asn substitution renders the quinolone resistance in S. pneumoniae.
DNA Topoisomerase (ATP-Hydrolysing)/genetics*
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Drug Resistance, Microbial/genetics*
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Human
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Isoenzymes/genetics*
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Mutation/genetics*
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Quinolones*
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Streptococcus pneumoniae/genetics
2.Cerebral Cavernous Malformation (CCM)-like Vessel Lesion in the Aged ANKS1A-deficient Brain
Jiyeon LEE ; Haeryung LEE ; Miram SHIN ; Soochul PARK
Experimental Neurobiology 2023;32(6):441-452
In this study, we show that ANKS1A is specifically expressed in the brain endothelial cells of adult mice. ANKS1A deficiency in adult mice does not affect the differentiation, growth, or patterning of the cerebrovascular system; however, its absence significantly impacts the cerebrovascular system of the aged brain. In aged ANKS1A knock-out (KO) brains, vessel lesions exhibiting cerebral cavernous malformations (CCMs) are observed.In addition, CCM-like lesions show localized peripheral blood leakage into the brain. The CCM-like lesions reveal immune cells infiltrating the parenchyma. The CCM-like lesions also contain significantly fewer astrocyte endfeets and tight junctions, indicating that the integrity of the BBB has been partially compromised. CCM-like lesions display increased fibronectin expression in blood vessels, which is also confirmed in cultured endothelial cells deficient for ANKS1A. Therefore, we hypothesize that ANKS1A may play a role in maintaining or stabilizing healthy blood vessels in the brain during aging.
3.A study on dentist and dental hygienist burnout
Yuyi PARK ; Jihyun LEE ; Sohwi BAE ; Kichan LEE ; Sangheuk LEE ; Soojin JANG ; Haeryung HUR ; Younghoon PARK
Journal of Korean Academy of Oral Health 2019;43(2):100-108
OBJECTIVES: Dentists and dental hygienists undergo high levels of stress due to various factors and the burnout of health-care personnel is very important in the context of personal and social problems. Therefore, empirical research reflecting the social, cultural, and special circumstances of the medical environment is necessary. Here, we explore the causes and outcomes of burnout in dentists and dental hygienists and present ways to prevent burnout. METHODS: A cross-sectional research design was used to measure burnout of 141 dentists and 61 dental hygienists. A structured questionnaire containing the Maslach Burnout Inventory (MBI) was administered from May to June, 2018. Data were analyzed using SPSS 25.0, descriptive statistics, t-test, Mann-Whitney test, Kruskall-Wallis test, and multiple regression analysis. RESULTS: Each participant's MBI was measured in three aspects (emotional exhaustion, depersonalization, and personal accomplishment). The MBI scores of dentists with regards to their emotional exhaustion, depersonalization, and personal accomplishment were 24.8%, 34%, and 48.2%, respectively. Alternatively the scores of dental hygienists were 45.9%, 44.3% and 52.5%, respectively, for the same parameters. While the factors affecting the burnout of dentists and dental hygienists were different, it had a negative impact on the professional performance of both. CONCLUSIONS: According to the results of this study, Korean dentists and dental hygienists experience high levels of work-related burnouts. This can have adverse impacts on their personal health and that of their patients. Therefore, stress management is necessary in dentists and dental hygienists.
Dental Hygienists
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Dentists
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Depersonalization
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Empirical Research
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Humans
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Research Design
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Social Problems
4.Pathological Analysis of 1,000 Cases of Transrectal Ultrasoundguided Systematic Prostate Biopsy: Establishment of New Sample Processing Method and Diagnostic Utility of Immunohistochemistry.
Chang Lim HYUN ; Hee Eun LEE ; Haeryung KIM ; Hye Seung LEE ; So Yeon PARK ; Jin Haeng CHUNG ; Gheeyoung CHOE
Korean Journal of Pathology 2006;40(6):406-419
BACKGROUND: We developed a new processing method for extended prostate needle biopsy, and evaluated diagnostic utility of routine immunohistochemistry in 1,000 consecutive unselected cases of transrectal ultrasound-guided systematic prostate biopsy. METHODS: Four to five biopsy cores were embedded in one paraffin block. All the biopsy cores were immunohistochemically stained with basal cell markers. RESULTS: The new sample processing method was technically perfect for making a diagnosis from extended prostate needle biopsy. Among 1,000 cases, there were 323 cases (32.3%) of adenocarcinoma, 5 cases of other malignant tumors, 9 cases of high-grade prostatic intraepithelial neoplasia without a carcinoma, and only 8 cases of atypical small acinar proliferation. Among the 323 cases of adenocarcinoma, there were 38 cases (11.8%) of microcarcinomas <0.1 cm and 101 cases (31.3%) of small adenocarcinomas <0.3 cm in length. In the needle biopsy specimens, 59 cases (18.3%) were classified as clinically insignificant carcinomas. Among them, 37 cases underwent radical prostatectomy, which turned out to be clinically significant carcinomas in 24 cases (64.9%). CONCLUSIONS: Routinely performed immunohistochemistry combined with the new sample processing method is very effective for detecting microscopic carcinoma foci as well as differentiating carcinoma from benign conditions mimicking cancer.
Adenocarcinoma
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Biopsy*
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Biopsy, Needle
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Diagnosis
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Immunohistochemistry*
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Paraffin
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Prostate*
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Prostatectomy
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Prostatic Intraepithelial Neoplasia
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Prostatic Neoplasms