Search Results (3)

Background/Objectives: As the population of women with endometriosis increases, approximately 10% of those of reproductive age experience symptoms such as pelvic pain, painful menstruation, and infertility. Individuals with endometriosis usually undergo multiple surgeries due to the high recurrence rate of the condition. However, ovarian surgery tends to reduce the ovarian reserve, presenting a dilemma when deciding whether to recommend surgery or medical treatment for women of reproductive age. The impact of endometriomas on the residual volume of ovarian tissue remains controversial, and it is unclear whether endometriosis itself or endometriomas are the primary problem. In this study, we aimed to investigate whether women with endometriosis have lower levels of anti-Müllerian hormone than women with healthy ovaries before treatment initiation. Methods: A total of 298 participants enrolled in the endometriosis cohort at Severance Hospital, Korea, from 1 October 2020 to 1 July 2024 were included in this study. Of these, 63 participants were from a retrospective study, and 235 were from a prospective study. Due to the use of different assay methods between the reference values and anti-Müllerian hormone measurements from Severance Hospital, a correction was applied using the regression equation. The mean anti-Müllerian hormone levels for individuals with endometriosis were corrected with the regression equation and compared to those of the reference group for each age group using a one-sample t-test. Results: Anti-Müllerian hormone levels decreased with age in the endometriosis group. When comparing mean anti-Müllerian hormone concentrations between the endometriosis group and reference values, among 168 participants aged 20–31 years, the corrected mean anti-Müllerian hormone concentration was 5.96 ± 3.22 ng/mL, higher than the reference value of 4.94 ± 0.17 ng/mL (p < 0.01). Among 31 participants aged 35–37 years, the corrected average anti-Müllerian hormone value was 4.33 ± 3.06 ng/mL, compared to the reference anti-Müllerian hormone level of 3.22 ± 0.15 ng/mL (p = 0.05). There were no significant differences in corrected anti-Müllerian hormone levels between the 32–34-, 38–40-, 41–43-, and ≥44 years age groups. Conclusions: Patients with endometriosis, especially those aged 20–31 years, tended to have higher anti-Müllerian hormone levels than did individuals with healthy ovaries. In other age groups, there were no differences. Given that these levels do not differ significantly across age groups, it is difficult to conclude that patients with endometriosis have a reduced ovarian reserve. Full article

(1) Background: Continuous monitoring of tacrolimus (TAC), mycophenolic acid (MPA), and creatinine (Cre) after renal transplantation is vitally important. In this study, we developed a new method based on volumetric absorptive microsampling (VAMS) combined with Ultra Performance Liquid Chromatography–Tandem Mass Spectrometry (UPLC-MS/MS) to simultaneously quantify three analytes including TAC, MPA, and Cre in whole blood. (2) Methods: The VAMS-based UPLC-MS/MS assay used a shared extraction and a single injection to simultaneously quantify the included TAC, MPA, and Cre. Development and validation were carried out following the Food and Drug Administration and European Medicines Agency guidelines for the validation of bioanalytical methods. Moreover, clinical validation for the three analytes was performed in both dried blood spot (DBS) and VAMS. Furthermore, a willingness survey was conducted using the system usability scale (SUS) for renal transplant recipients. (3) Results: The assay was successfully validated for all analytes. No interference, carryover, or matrix effects were observed, and extraction recoveries and process efficiencies were >90.00%. Analysis was unaffected by hematocrit (0.20~0.60, L/L) and anticoagulants (EDTA-2K). Dried VAMS samples were stable for 7 days at ambient temperature and stable for at least 1 month at −20 °C. During clinical validation, the measured TAC, corrected MPA, and Cre concentrations of VAMS samples met the analytical standards (95.00%, 88.57%, and 92.50%). When more stringent clinical acceptance criteria were set, the results obtained by VAMS (90.00%, 71.43%, and 85.00%) better than DBS (77.50%, 62.86%, and 70.00%). Compared with DBS, the survey found that renal transplant recipients are more inclined to use VAMS. (4) Conclusions: A robust extraction and UPLC-MS/MS analysis method in VAMS tips was developed and fully validated for the simultaneous quantification of TAC, MPA, and Cre concentrations. This method provides analytical support for the one-sample remote monitoring of both immunosuppressive drug concentrations and renal function in allo-renal recipients. Based on the good consistency between this method and the routine detection of venous blood samples and higher patient satisfaction than DBS, we believe that VAMS sampling can be a better alternative to venous whole-blood sampling. Full article

Förster resonance energy transfer (FRET) technology has been widely used in biological and biomedical research. This powerful tool can elucidate protein interactions in either a dynamic or steady state. We recently developed a series of FRET-based technologies to determine protein interaction dissociation constant and for use in high-throughput screening assays of SUMOylation. SUMO (small ubiquitin-like modifier) is conjugated to substrates through an enzymatic cascade. This important posttranslational protein modification is critical for multiple biological processes. Sentrin/SUMO-specific proteases (SENPs) act as endopeptidases to process the pre-SUMO or as isopeptidases to deconjugate SUMO from its substrate. Here, we describe a novel quantitative FRET-based protease assay for determining the kinetics of SENP1. Our strategy is based on the quantitative analysis and differentiation of fluorescent emission signals at the FRET acceptor emission wavelengths. Those fluorescent emission signals consist of three components: the FRET signal and the fluorescent emissions of donor (CyPet) and acceptor (YPet). Unlike our previous method in which donor and acceptor direct emissions were excluded by standard curves, the three fluorescent emissions were determined quantitatively during the SENP digestion process from onesample. New mathematical algorithms were developed to determine digested substrate concentrations directly from the FRET signal and donor/acceptor direct emissions. The kinetic parameters, k_cat, K_M, and catalytic efficiency (k_cat/K_M) of SENP1 catalytic domain for pre-SUMO1/2/3 were derived. Importantly, the general principles of this new quantitative methodology of FRET-based protease kinetic determinations can be applied to other proteases in a robust and systems biology approach. Full article