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Objective MicroRNAs (miRNAs), small noncoding RNA molecules, are involved in the pathogenesis of various diseases such as cancer and arthritis. The aim of this study was to determine whether miR-127-5p regulates interleukin-1β (IL-1β)-induced expression of matrix metalloproteinase 13 (MMP-13) and other catabolic factors in human chondrocytes. Methods Expression of miR-127-5p and MMP-13 by normal and osteoarthritic (OA) human cartilage was determined using real-time polymerase chain reaction. The effect of miR-127-5p on MMP-13 expression was evaluated using transient transfection of human chondrocytes or chondrogenic SW-1353 cells with miR-127-5p or its antisense inhibitor (anti-miR-127-5p). MMP-13 protein production was quantified by enzyme-linked immunosorbent assay, and the involvement of miR-127-5p in IL-1β-mediated catabolic effects was examined by immunoblotting. MicroRNA-127-5p binding with the putative site in the 3′-untranslated region (3′-UTR) of MMP-13 messenger RNA (mRNA) was validated by luciferase reporter assay. Results There was a significant reduction in miR-127-5p expression in OA cartilage compared with normal cartilage. Up-regulation of MMP-13 expression by IL-1β was correlated with down-regulation of miR-127-5p expression in human chondrocytes. MicroRNA-127-5p suppressed IL-1β-induced MMP-13 production as well as the activity of a reporter construct containing the 3′-UTR of human MMP-13 mRNA. In addition, mutation of the miR-127-5p binding site in the 3′-UTR of MMP-13 mRNA abolished miR-127-5p-mediated repression of reporter activity. Conversely, treatment with anti-miR-127-5p remarkably increased reporter activity and MMP-13 production. Interestingly, the IL-1β-induced activation of JNK, p38, and NF-κB and expression of MMP-1 and cyclooxygenase 2 were significantly inhibited by miR-127-5p. Conclusion MicroRNA-127-5p is an important regulator of MMP-13 in human chondrocytes and may contribute to the development of OA. [ABSTRACT FROM AUTHOR]

Background. The role of the new Myocbacterium tuberculosis–specific enzyme-linked immunosorbent spot (ELISPOT) assay for diagnosis of tuberculous meningitis (TBM) has not yet been fully assessed. Here, we conducted a prospective, blinded, observational study to evaluate the diagnostic accuracy of this assay, compared with the conventional tests, for diagnosing TBM.Methods. All adult patients with suspected TBM were enrolled at a tertiary care hospital (Seoul, South Korea) during a 12-month period. ELISPOT assays were performed on peripheral mononuclear cells and mononuclear cells from cerebrospinal fluid (CSF).Results. Eighty-nine patients with suspected TBM were enrolled. Of these, 31 (35%) were classified as having TBM (10 confirmed, 6 highly probable, and 15 probable cases), and 55 (62%) were classified as not having active tuberculosis. The remaining 3 (3%) with possible TBM were excluded from the final analysis. The sensitivities and specificities, respectively, of the tested methods for diagnosing TBM were as follows: CSF adenosine deaminase level >5.8 U/L, 89% (95% confidence interval [CI], 69%–98%) and 73% (95% CI, 58%–84%); peripheral mononuclear cells ELISPOT, 71% (95% CI, 51%–86%) and 57% (95% CI, 42%–70%); and CSF mononuclear cells ELISPOT assay, 59% (95% CI, 36%–79%) and 89% (95% CI, 72%–98%). The combined sensitivity of an adenosine deaminase level >5.8 U/L or a positive peripheral mononuclear cells ELISPOT assay result was 94% (95% CI, 79%–99%), conferring a negative likelihood ratio of 0.14 (95% CI, 0.03–0.55) when both test results were negative.Conclusion. ELISPOT assays using peripheral mononuclear cells and CSF mononuclear cells are useful adjuncts to the current tests for diagnosing TBM, particularly when used in combination with the assessment of adenosine deaminase level in CSF. [ABSTRACT FROM PUBLISHER]

Objectives: To investigate antibody production in asymptomatic and mild COVID-19 patients. Methods: Sera from asymptomatic to severe COVID-19 patients were collected. Microneutralization (MN), fluorescence immunoassay (FIA), and enzyme-linked immunosorbent assay (ELISA) were performed. Results: A total of 70 laboratory-confirmed COVID-19 patients were evaluated, including 15 asymptomatic/anosmia, 49 mild symptomatic, and 6 pneumonia patients. The production of the neutralizing antibody was observed in 100% of pneumonia, 93.9% of mild symptomatic, and 80.0% of asymptomatic/anosmia groups. All the patients in the pneumonia group showed high MN titer (≥1:80), while 36.7% of mild symptomatic and 20.0% of asymptomatic/anosmia groups showed high titer (p < 0.001). Anti-SARS-CoV-2 antibodies could be more sensitively detected by FIA IgG (98.8%) and ELISA (97.6%) in overall. For the FIA IgG test, all patients in the pneumonia group exhibited a high COI value (≥15.0), while 89.8% of mild symptomatic and 73.3% of asymptomatic/anosmia groups showed a high value (p = 0.049). For the ELISA test, all patients in the pneumonia group showed a high optical density (OD) ratio (≥3.0), while 65.3% of mild symptomatic and 53.3% of asymptomatic/anosmia groups showed a high ratio (p = 0.006). Conclusions: Most asymptomatic and mild COVID-19 patients produced the neutralizing antibody, although the titers were lower than pneumonia patients. ELISA and FIA sensitively detected anti-SARS-CoV-2 antibodies. [ABSTRACT FROM AUTHOR]

There are few data on donor screening for latent tuberculosis infection (LTBI) using the tuberculin skin test (TST) and interferon-gamma releasing assay (IGRA). In South Korea, most renal allografts involve living donors (average, 80 %). Hence, we have an opportunity to evaluate donor and recipient screening for LTBI by TST and IGRA. All donors and recipients admitted for kidney transplantation during a 20-month period were evaluated prospectively by using TST and Mycobacterium tuberculosis-specific enzyme-linked immunosorbent spot (ELISPOT) assay. The study population consisted of 205 living donor-recipient pairs (≥16 years) including 15 (7 %) who yielded indeterminate donor or recipient ELISPOT results. Of the 205 donors, 63 (31 %) gave a positive TST ≥5 mm, 33 (16 %) a positive TST ≥10 mm, and 96 (47 %) a positive ELISPOT. Of the 205 recipients, 9 (5 %) gave a positive TST ≥5 mm, 3 (2 %) a positive TST ≥10 mm, and 79 (39 %) had a positive ELISPOT. Of the 205 donor-recipient pairs, only 59 (29 %) gave negative donor and recipient ELISPOT results and 139 (68 %) negative donor and recipient TSTs (<5 mm) ( P < 0.001). One third of donor-recipient pairs tends to be positive in the TST, and two thirds of the donor-recipient pairs tends to be positive in the ELISPOT. Given the high positive rate of LTBI obtained by screening donors, further studies on the clinical value of solid organ transplant donors with positive TST or ELISPOT and health economics analysis in countries with intermediate burden of TB are needed for policy decisions on isoniazid (INH) prophylaxis. [ABSTRACT FROM AUTHOR]

Abstract: As part of our search for botanical sources of SARS-CoV 3CLpro inhibitors, we selected Torreya nucifera, which is traditionally used as a medicinal plant in Asia. The ethanol extract of T. nucifera leaves exhibited good SARS-CoV 3CLpro inhibitory activity (62% at 100μg/mL). Following bioactivity-guided fractionation, eight diterpenoids (1–8) and four biflavonoids (9–12) were isolated and evaluated for SARS-CoV 3CLpro inhibition using fluorescence resonance energy transfer analysis. Of these compounds, the biflavone amentoflavone (9) (IC50 =8.3μM) showed most potent 3CLpro inhibitory effect. Three additional authentic flavones (apigenin, luteolin and quercetin) were tested to establish the basic structure–activity relationship of biflavones. Apigenin, luteolin, and quercetin inhibited 3CLpro activity with IC50 values of 280.8, 20.2, and 23.8μM, respectively. Values of binding energy obtained in a molecular docking study supported the results of enzymatic assays. More potent activity appeared to be associated with the presence of an apigenin moiety at position C-3′ of flavones, as biflavone had an effect on 3CLpro inhibitory activity. [ABSTRACT FROM AUTHOR]

Among noninvasive rapid tests available within 3–5 days, enzyme-linked immunospot assay had the highest sensitivity in patients with miliary tuberculosis, compared with acid-fast bacilli, Mycobacterium tuberculosis polymerase chain reaction, and tuberculin skin test.Forty-three patients with miliary tuberculosis were evaluated for diagnostic usefulness of enzyme-linked immunospot (ELISPOT) assay. Among noninvasive rapid tests available within 3–5 days, ELISPOT had the highest sensitivity (93%), compared with acid-fast bacilli stain (sputum, 32% and bronchoalveolar lavage, 7%), Mycobacterium tuberculosis polymerase chain reaction (sputum, 53% and bronchoalveolar lavage, 36%), and tuberculin skin test (22%). In comparison with 44 patients with lymph node tuberculosis, the sensitivity of the ELISPOT assay in patients with miliary tuberculosis (93%) was as high as in those with lymph node tuberculosis (95%, P = .63), whereas the sensitivity of the tuberculin skin test was substantially lower in patients with miliary tuberculosis (22%) than in those with lymph node tuberculosis (73%, P < .001). [ABSTRACT FROM PUBLISHER]