Monoclonal protein (M-protein) is a crucial biomarker for diagnosing and monitoring monoclonal gammopathies, including multiple myeloma (MM). Traditionally, electrophoresis (EP)-based methods, such as protein EP and immunofixation EP, have been widely used for M-protein detection. However, these methods can show low sensitivity and inadequate quantification of small amounts of M-protein. To overcome these challenges, EP-based methods are often combined with the quantification of serum free light chains in automated immunoassays. Advances in mass spectrometry (MS) have introduced three main approaches for sample preparation: top-down, middle-down, and bottom-up. Middle-down approaches are commonly used with matrix-assisted laser desorption/ionization time-offlight MS and liquid chromatography–electrospray ionization (LC–ESI) quadrupole time-offlight MS, whereas the bottom-up approach is typically applied with LC–ESI Orbitrap MS. A review of studies, conducted from 2014 to 2024, on plasma cell disorders that utilized MS-based methods demonstrate improvements in the sensitivity and accuracy of M-protein identification and quantification. MM remains the most frequently studied disease, with significant therapeutic advancements leading to improved outcomes. Minimal residual disease has gained attention because of its correlation with better prognoses. Monoclonal gammopathy of undetermined significance and amyloid light-chain amyloidosis are occasionally addressed, while studies on other rare diseases remain limited. This review highlights the clinical applications and advancements in MS-based methods, particularly in assessing M-protein levels for treatment responses, risk factors, and prognostic monitoring. Given their advantages—high sensitivity and specificity, automation, cost-effectiveness, and time efficiency—MS-based methods may eventually replace EP-based methods in clinical laboratories.

OBJECTIVES: This study aimed to describe the process of utilizing a mobile application for ecological momentary assessment (EMA) to collect data on stress and mood in daily life setting. METHODS: A mobile application for the Android operating system was developed and installed with a set of questions regarding momentary mood and stress into a smartphone of a participant. The application sets alarms at semi-random intervals in 60-minute blocks, four times a day for 7 days. After obtaining all momentary affect and stress, the questions to assess the usability of the mobile EMA application were also administered. RESULTS: The data were collected from 97 police officers working in Gyeonggi Province of South Korea. The mean completion rate was 60.0% ranging from 3.5% to 100%. The means of positive and negative affect were 18.34 of 28 and 19.09 of 63. The mean stress was 17.92 of 40. Participants responded that the mobile application correctly measured their affect (4.34 ± 0.83) and stress (4.48 ± 0.62) of 5-point Likert scale. CONCLUSIONS: Our study investigated the process of utilizing a mobile application to assess momentary affect and stress at repeated times. We found challenges regarding adherence to the research protocol, such as completion and delay of answering after alarm notification. Despite this inherent issue of adherence to the research protocol, the EMA still has advantages of reducing recall bias and assessing the actual moment of interest at multiple time points that improves ecological validity.
Bias (Epidemiology) ; Gyeonggi-do ; Humans ; Korea ; Methyltestosterone ; Mobile Applications* ; Police ; Smartphone ; Stress, Psychological

BACKGROUND: Mycobacterial culture is the gold standard test for diagnosing tuberculosis (TB), but it is time-consuming. Polymerase chain reaction (PCR) is a highly sensitive and specific method that can reduce the time required for diagnosis. The diagnostic efficacy of PCR differs, so this study determined the actual sensitivity of TB-PCR in tissue specimens. METHODS: We retrospectively reviewed 574 cases. The results of the nested PCR of the IS6110 gene, mycobacterial culture, TB-specific antigen-induced interferon-γ release assay (IGRA), acid-fast bacilli (AFB) staining, and histological findings were evaluated. RESULTS: The positivity rates were 17.6% for PCR, 3.3% for the AFB stain, 22.2% for mycobacterial culture, and 55.4% for IGRA. PCR had a low sensitivity (51.1%) and a high specificity (86.3%) based on the culture results of other studies. The sensitivity was higher (65.5%) in cases with necrotizing granuloma but showed the highest sensitivity (66.7%) in those with necrosis only. The concordance rate between the methods indicated that PCR was the best method compared to mycobacterial culture, and the concordance rate increased for the methods using positive result for PCR or histologic features. CONCLUSIONS: PCR of tissue specimens is a good alternative to detect tuberculosis, but it may not be as sensitive as previously suggested. Its reliability may also be influenced by some histological features. Our data showed a higher sensitivity when specimens contained necrosis, which indicated that only specimens with necrosis should be used for PCR to detect tuberculosis.
Diagnosis* ; Granuloma ; Methods ; Necrosis ; Polymerase Chain Reaction* ; Retrospective Studies ; Sensitivity and Specificity ; Tuberculosis*