Lee EH, et al. J Korean Med Sci. 2012 Sep;27(9):1091-1097. http://dx.doi.org/10.3346/jkms.2012.27.9.1091

Kyoung-Jin Park, M.D., Seungman Park, M.D., Eunhee Lee, M.D., Jong-Ho Park, B.S., June-Hee Park, B.S., Hyung-Doo Park, M.D., Soo-Youn Lee, M.D., and Jong-Won Kim, M.D.. Ann Lab Med 2016;36:561-72. https://doi.org/10.3343/alm.2016.36.6.561

Background: Limited data are available for validation of low-density lipoprotein cholesterol (LDL) calculation (LDL_cal) in the adult Korean population. The aim of this study was to develop and validate a new equation for LDL_cal and to compare it with previous such equations in a Korean population. Methods: A new equation for LDL_cal was developed (LDL_Choi). LDL_Choi and 11 other previously published equations were applied and compared with directly measured LDL concentration (LDL_direct) in a development cohort (population 1), an independent validation cohort in the same laboratory (population 2), and the Korea National Health and Nutrition Examination Survey 2017 cohort (population 3). Results: Among the 12 equations, the newly-developed equation (LDL_Choi = total cholesterol – 0.87 x high-density lipoprotein cholesterol – 0.13 x triglycerides) had the highest intraclass correlation coefficient (ICC) and the lowest mean systemic difference and median absolute percentage error in populations 1 and 2 but not in population 3. Subgroup analysis showed good agreement between LDL_Choi and LDL_direct (ICC > 0.75) in population 2, whose LDL_direct < 70 mg/dL. For samples with high triglycerides (> 400 mg/dL), equation accuracy varied. Categorization concordance according to the National Cholesterol Education Program Adult Treatment Panel III criteria with the other 11 equations were less than 80%; that of LDL_Choi was 87.6 and 87.4% in populations 1 and 2, respectively. Conclusions: Accuracy of 12 equations for LDL_cal varied by cohort and subgroup based on LDL_direct and triglycerides. A laboratory-specific equation for LDL_cal and/or LDL_direct may be needed for accurate evaluation of LDL status.

Background: The aim of this study was to investigate the seroprevalence of cytomegalovirus (CMV) infection using the serologic status of CMV IgG and IgM antibodies in Korean women of childbearing age.Methods: We retrospectively reviewed CMV IgG and IgM test results from Korean women aged 15–49 years who underwent testing between January 2009 and December 2019. Seroprevalence of CMV IgG and IgM by year and age was investigated.Results: The study period was 11 years, and among 6837 samples tested, 95.8% were CMV IgG–positive. The seropositivity in women aged 15‐ <20 years was significantly lower (77.5%) than older age groups. Among 6837 total CMV IgG tests, 75.9% (5186) had concurrently measured CMV IgM results among which 2.4% were IgM‐positive.Conclusion: Considering the low CMV seropositivity of women younger than 20 years, they may need prenatal education for CMV infection.

Diminished ovarian reserve can be assessed biochemically using serum anti-Müllerian hormone (AMH) and follicle-stimulating hormone (FSH) tests. This study aimed to evaluate the prevalence of diminished ovarian reserve in a large population of reproductive-aged women by age and geographic region in Korea using different cutoffs of serum AMH and FSH levels. In 2022, 13,351 women underwent both AMH and FSH tests. The prevalence of diminished ovarian reserve increased markedly with age. Although cutoffs for AMH and FSH levels are different in USA and Korean guidelines, the overall prevalence of diminished ovarian reserve was comparable. The maximum prevalence was 3.8%, 6.0%, 11.0%, 28.6%, 69.3%, and 95.0% in women aged 20–24, 25–29, 30–34, 35–39, 40–44, and 45–49 years, respectively. The overall prevalence and age-adjusted prevalence of diminished ovarian reserve were 37.2% and 38.4%, respectively. Women who had only increased serum FSH without decreased AMH represented 1.1% (by Korean guidelines) and 2.5% (by USA guidelines) of all women. Serum AMH and FSH tests were underutilized on Jeju Island. The results of this study provide basic knowledge about diminished ovarian reserve for use in infertility support programs and the field of maternal aging.

The farAB operon encodes an efflux pump system that mediates the resistance of Neisseria gonorrhoeae to antimicrobial long-chain fatty acids. We previously observed that expression of farAB is negatively regulated by the FarR repressor. In this study, we examined the molecular mechanism by which FarR represses expression of farAB. DNase I footprinting analysis, coupled with a deletion analysis of the farAB promoter region, indicated that FarR binds to three sites (termed sites A, B and C) within the DNA sequence upstream of farA; genetic analysis revealed, however, that site B is not required for FarR repression of farAB. This repression also required the presence of Integration Host Factor (IHF), which was found to bind to sequences located between FarR binding sites A and C. We determined that IHF binding to the farAB promoter region could inhibit transcription in vitro and that such binding induced a bending of the target DNA, which we propose to be important in regulating this operon. IHF binding to the promoter region was found to stabilize the binding of FarR to its binding sites A and C and as a consequence, enhanced repression of farAB expression mediated by FarR. We propose a model in which expression of the farAB-encoded efflux pump in N. gonorrhoeae is modulated by the DNA binding activities of FarR and IHF.