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Background: A novel enzymatic HbA1c assay was introduced for use in an automated chemistry analyzer. With this unique method, HbA1c and plasma glucose can be measured from the same EDTA tube. We evaluated the analytical performance of this enzymatic HbA1c assay in a JCA-BM6010/C analyzer and compared the HbA1c values with the results from other widely used methodological instruments. Methods: The imprecision, linearity, carry-over and concordance rate of the enzymatic HbA1c test (BM Test HbA1c) using the JCA-BM6010/C analyzer were evaluated. Three hundred and seventy-seven specimens with HbA1c concentrations from 16 to 133 mmol/mol were used for a comparison study with two high performance liquid chromatography methods: Variant II Turbo and Tosoh HLC 723 G8 and the AutoLab Hemoglobin A1c immunoturbidimetry reagent using a Hitachi 7600-110. Forty specimens were used for the glucose method comparison. Results: The HbA1c coefficients of variation of the within-run imprecision for low and high levels were 0.6% and 0.4%, respectively. The linearity of the BM Test HbA1c using the JCA-BM6010/C analyzer was excellent in the range between 31 mmol/mol and 143 mmol/mol. The carry-over rate was 0.2%. The relationships between the BM test and the other three methods were 0.916×Tosoh G8+3.644, r=0.986; 0.887×Bio-Rad Variant II+1.896, r=0.972; and 0.941×AutoLab+4.532, r=0.977. The concordance rates using a cut-off of 48 mmol/mol were 91.5% with Tosoh G8, 82.8% with Bio-Rad Variant II, and 91.0% with AutoLab. The simultaneously assayed plasma glucose with HbA1c was 1.002×Routine plasma glucose+0.625, r=1.000 Conclusions: The enzymatic BM Test HbA1c in the JCA-BM6010/C analyzer showed excellent precision and linearity, and a minimal carry-over rate. The simultaneously assayed plasma glucose analysis showed good performance. [ABSTRACT FROM AUTHOR]

To assess the diagnostic utility of bone turnover markers (BTMs) and demographic variables for identifying individuals with osteoporosis. A cross-sectional study involving 280 participants was conducted. Serum BTM values were obtained from 88 patients with osteoporosis and 192 controls without osteoporosis. Six machine learning models, including extreme gradient boosting (XGBoost), light gradient boosting machine (LGBM), CatBoost, random forest, support vector machine, and k-nearest neighbors, were employed to evaluate osteoporosis diagnosis. The performance measures included the area under the receiver operating characteristic curve (AUROC), F1-score, and accuracy. After AUROC optimization, LGBM exhibited the highest AUROC of 0.706. Post F1-score optimization, LGBM's F1-score was improved from 0.50 to 0.65. Combining the top three optimized models (LGBM, XGBoost, and CatBoost) resulted in an AUROC of 0.706, an F1-score of 0.65, and an accuracy of 0.73. BTMs, along with age and sex, were found to contribute significantly to osteoporosis diagnosis. This study demonstrates the potential of machine learning models utilizing BTMs and demographic variables for diagnosing preexisting osteoporosis. The findings highlight the clinical relevance of accessible clinical data in osteoporosis assessment, providing a promising tool for early diagnosis and management., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: Although real-time reverse transcription-PCR (RT-PCR) is the gold standard for diagnosing coronavirus disease 2019 (COVID-19), simpler and faster antibody detection tests can be complementary for diagnosis of COVID-19. To manage the COVID-19 pandemic, the need for serologic testing has increased. In this report, the newly developed antibody detection assays ACCEL ELISA COVID-19 (ACCEL) and Elecsys anti-SARS-CoV-2 (Elecsys) were evaluated., Methods: Serum samples submitted for routine laboratory testing were analyzed (66 and 161 PCR-positive and PCR-negative samples). After the samples were aliquoted, antibody detection tests were performed using ACCEL and Elecsys assays., Results: When detection of viral RNA using RT-PCR was set as the reference method for diagnosis of COVID-19, the sensitivity was 83.3% and 75.8, and the specificity was 96.9 and 99.4% in ACCEL and Elecsys, respectively. The true positivity rates of ACCEL and Elecsys assays were 57.1%/42.9%, 57.1%/28.6%, 77.8%/66.7%, and 97.1%/97.1% among the specimens collected ≤3, 4-7, 8-14, and >14 days after symptom onset, respectively., Conclusions: The ACCEL assay showed high sensitivity in samples collected within 7 days after symptom onset. Because many patients are asymptomatic in the early stage of SARS-CoV-2 infection, the ACCEL assay could be a good screening tool due to high sensitivity in the early stage of SARS-CoV-2 infection., (© 2022 by the Association of Clinical Scientists, Inc.)

Background: In response to inflammation, procalcitonin plasma concentrations increase more rapidly than other acute-phase reactants and higher values are associated with severe disease. Procalcitonin measurements assist in determining whether antibiotic therapy should be used. point-of-care testing (POCT) is performed for early decision making about additional testing or therapy. The ABSOGEN ™ PCT (Bumyoungbio, Inc., Suwon, Korea) is a rapid novel semi-quantitative immunochromatographic PCT assay that analyses whole blood samples. We compared the patient quantitative test results to ABSOGEN ™ PCT test results., Methods: Whole blood was loaded onto an ABSOGEN ™ PCT cartridge and incubated for 10 minutes. The color intensity of the band of the cartridge was measured using an accompanying device and with the naked eye. The results were graded as negative (<0.1 ng/mL), low (0.1 to <1.0 ng/mL), middle (1.0-2.0 ng/mL), and high (>2.0 ng/mL). A total of 158 specimens with procalcitonin levels measured from 0 to 18.96 ng/mL were used for comparison study., Results: The concordance rate between ABSOGEN ™ PCT using the reader and quantitative assay, between ABSOGEN ™ PCT using naked eyes and quantitative assay, and between ABSOGEN ™ PCT using the reader and naked eyes for the same category was 83.5% (P=.040), 78.5% (P<.001), and 82.3% (P=.001), respectively. The concordance rates for the ±1 categories were all 100%., Conclusion: ABSOGEN ™ PCT is an accurate assay. It is easy to use, simple, fast, portable. The assay has potential value in clinical applications, especially in emergency care., (© 2016 Wiley Periodicals, Inc.)

Background: This study compared the diagnostic power of isothermal target and probe amplification (iTPA) with the existing real-time PCR for the detection of Mycobacterium tuberculosis (MTB)., Method: The two molecular methods were performed using DNA extracted directly from lower respiratory tract samples, not from the culture broth. A total of 174 non-consecutive patients with suspected pulmonary tuberculosis were enrolled in this study. Acid-fast bacilli (AFB) stain and liquid culture with the BACTEC MGIT 960 system (Becton Dickinson Diagnostic, USA) were performed. Real-time PCR and iTPA methods were performed with the AdvanSure TB/NTM TaqMan assay (LG Lifescience, Korea) and the RapiDx® MTB test (RapleGene, Korea)., Results: Among 174 patients, 49 of 52 isolates were identified as MTB and 3 of 52 isolates were identified as non-tuberculous mycobacteria NTM. Based on the culture results, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 95.9%, 90.1%, 81.3%, and 98.2% for iTPA, and 95.7%, 91.0%, 80.4%, and 98.2% for real-time PCR, respectively. The agreement of iTPA was 83.0% with the AFB stain, 92.4% with the MGIT culture, and 94.2% with real-time PCR. Disagreement between the two molecular methods occurred in 10 patients., Conclusions: This study is the first to report the evaluation of iTPA conducted from direct specimens. Both iTPA and real-time PCR proved to be rapid, sensitive, and specific tools for the detection of MTB in clinical samples. The iTPA method for the MTB detection revealed a high concordance rate with real-time PCR., (© 2016 by the Association of Clinical Scientists, Inc.)

The amount of heart-type fatty acid-binding protein (FABP3) in cardiomyocytes may affect the prognosis of patients with coronary atherosclerosis. In this study, we examined whether single nucleotide polymorphisms (SNPs) of the FABP3 gene were prognostic factors in patients with coronary atherosclerosis. We enrolled 100 patients with myocardial infarction and coronary atherosclerosis and 100 healthy individuals to assess the genotypes of four SNPs of the FABP3 gene (RS2271072, RS16834408, RS2279885, and RS10914367). The MI patients with coronary atherosclerosis exhibited a higher frequency (16%) of the C/G-G/G haplotype of RS2271072 and RS10914367 than healthy individuals (7%). Koreans with the C/G-G/G haplotype for these SNPs had a higher risk of MI than did Koreans with the G/G-A/A haplotype. We calculated an odds ratio of 2.83 (95% confidence interval: 1.01-7.96). In conclusion, the C/G-G/G haplotype at RS2271072 and RS10914367 SNPs of FABP3 might be a prognostic factor in patients with coronary atherosclerosis.

Background: We compared two automated Rapid Plasma Reagin (RPR) assay kits with a manual RPR assay kit to evaluate the possibility of using the two automated RPR assays as an alternative to the manual RPR assay for a quantitative monitoring., Methods: One hundred eighty-five samples were analyzed, including 16 sera from patients with primary, secondary, and latent syphilis. Measured RPR unit (R.U.) values of two automated RPR assay kits, Mediace RPR (Sekisui Chemical Co., Ltd, Japan) and HBi Auto RPR (HBI Co., Ltd, Korea), were compared with the RPR titers of Macro-Vue RPR card test (Becton Dickinson BD Microbiology systems, USA). As a confirmatory test, Anti-Treponema pallidum EUROLINE WB (IgG) and Anti-Treponema pallidum EUROLINE WB (IgM) (Euroimmun, Germany) were used., Results: There was a prozone effect with Mediace RPR at RPR titer (card test) of 1:16, but not with HBi Auto RPR. The R.U. values of the two automated RPR assays did not show proportional increase to the RPR titer. Agreement between manual RPR and two automated RPR assay kits, Mediace RPR assay and HBi Auto RPR assay, were 83.8% and 83.2%, respectively., Conclusions: The two automated RPR assay kits could not be used as an alternative to manual RPR test for quantitative analysis of RPR titer. As Mediace RPR shows a prozone effect at relatively low RPR titer, caution is needed in the interpretation of the measured values.

Background: The objective of this study was to evaluate the role of proteases on the degradation of parathyroid hormone (PTH) in blood samples., Methods: Protease inhibitors with specificity against serine proteases (aprotinin), cysteine proteases (E-64), serine and cysteine proteases (leupeptin), metalloproteases (EDTA), or a protease inhibitor cocktail with a broad spectrum of inhibitory activity were added to blood samples. After storage at room temperature (0-48 hr), PTH levels were measured., Results: PTH levels in samples with the protease inhibitor cocktail did not change significantly after 48 hr of storage at room temperature, but the average PTH levels decreased by 40.7% and 20.1%, in samples stored at room temperature and stored at 4 degrees C without protease inhibitors, respectively. PTH levels in samples with leupeptin were stable for up to 24 hr. After 48 hr, the mean PTH levels decreased by 17.1%, 16.0%, 26.2%, and 32.1%, with 500 KIU/mL aprotinin, 100 micromol/L leupeptin, 10 micromol/L E-64, and 10 micromol/L EDTA, respectively, in the samples stored at room temperature., Conclusions: The decrease in PTH levels in blood samples seemed to be due to the degradation of PTH by proteases. Various proteases, including especially serine proteases, would act together to degrade PTH in blood specimen. The PTH degradation may be inhibited in blood specimen with protease inhibitor cocktail.

Objectives: We investigated the occurrence and mechanism of amikacin resistance and its association with various beta-lactamase genes in Pseudomonas aeruginosa isolates., Methods: Of the total 250 consecutive, non-duplicated isolates of P. aeruginosa, 55 isolates showed amikacin resistance. PCR amplification of genes for aminoglycoside (AG)-modifying enzymes [aac(3)-I, aac(3)-II/VI, aac(3)-III/IV, aac(6')-I, aac(6')-II, ant(2'')-I, ant(4')-II and aph(3')-VI], 16S rRNA methylases (rmtA, rmtB, rmtC and armA) and class 1 integrons was performed. In addition, we analysed the association of AG resistance genes with various beta-lactamase genes., Results and Conclusions: In Korea, the amikacin resistance rate in P. aeruginosa was high (22%), and it varied among provinces (3.8% to 40%). Four types of AG-modifying enzyme genes [aph(3')-VI, ant(2'')-I, aac(6')-I and aac(3)-II/VI] were found in 48 isolates. Thirty-six strains harboured two or more types of enzymes, of which a combination of aph(3')-VI and ant(2'')-I was the most frequent (24/36 isolates, 66.7%). None harboured aac(3)-I, aac(3)-III/IV, aac(6')-II, ant(4')-II, rmtA, rmtB, rmtC or armA. Forty-two isolates co-harboured beta-lactamase genes (mostly bla(OXA-10)). A class 1 integron was detected in all but one, and all the ant(2'')-I and 26/29 bla(OXA-10) were found in it. In contrast, aph(3')-VI was not found to be associated with the class 1 integron. Considering the possibility of co-selection and dissemination, constant monitoring of resistance evolution is necessary.

The levels of monocyte intracellular monokines (TNFalpha, MIP, and MIG) in patients with cancer or bacterial infection were studied by multiparameter flow cytometry and comparative fluorescence analysis. TNFalpha, MIP, and MIG levels in peripheral blood of patients with cancer or bacterial infection were higher than in normal controls (p < 0.005). In normal controls, no significant relationships were found among TNFalpha, MIG, MIP levels, monocyte count, and lymphocyte count in peripheral blood. In cancer patients, TNFalpha was strongly related to MIP (r = 0.809, p < 0.001) and MIG (r = 0.773, p < 0.001). Of the 3 monokines, TNFalpha and MIG levels were related to monocyte count, but none showed correlation with lymphocyte count in cancer patients. In patients with bacterial infection, TNFalpha was not significantly related to MIP (r = 0.423, p = 0.051), but it was related to MIG (r = 0.457; p = 0.033). None of the monokines (TNFalpha, MIP, MIG) was related to the monocyte count, but the MIP level was related to the peripheral blood lymphocyte count in patients with bacterial infection (r = 0.559, p = 0.008). These results suggest that circulating monocytes may play an important role in both cancer and bacterial infection through increased production of monokines. Moreover, correlations of the monokine levels with each other and their relationships to the monocyte count differ in patients with cancer and bacterial infection.