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We validated candidate biomarkers using circulating miRNAs by analyzing serum miRNA concentrations from patients with gastric cancer (GC) to predict lymph node (LN) metastasis. In a pilot study, serum levels of miR-21, miR-27a, miR-106b, miR-146a, miR-148a, miR-223, and miR-433 were compared in 10 healthy donors, 16 LN-positive patients with GC, and 15 LN-negative patients with GC. Then, we compared the level of three miRNAs (miR-21, miR-146a, and miR-148a) with the total of 79 GC patients with or without LN metastasis. In the pilot study, miR-21, miR-27a, miR-106b, miR-146a, miR-148a, and miR-223 concentrations from LN-positive patients with GC were significantly different from those of LN-negative patients with GC (P < 0.001, P = 0.003, P = 0.033, P < 0.001, P <0.001, and P = 0.017, respectively). In the validation study, levels of miR-21, miR-146a, and miR-148a increased as pN stage increased (P < 0.001, P = 0.001, and P < 0.001, respectively). Levels of the miRNAs were significantly different between pN0 and pN0 in the pT1 group (P = 0.013, P = 0.004, and P = 0.035, respectively) and among clinical stages (P = 0.001, P = 0.002, and P < 0.001, respectively). No differences in miRNA levels were observed by pT stage, Lauren's classification, sex, or age. Serum concentrations of miR-21, miR-146a, and miR-148a were closely associated with GC pN stage. These serum miRNA levels could be biomarker candidates to predict the presence of LN metastasis.

ObjectivesThe stability of circulating proteins can be affected by repeated freezing and thawing. The aim of our study was to identify the effect of repeated freezing and thawing on the plasma and serum concentrations of eight proteins [interferon-γ, interleukin (IL)-8, IL-15, IL-17A, matrix metalloproteinase (MMP)-7, tumor necrosis factor-α, vascular endothelial growth factor (VEGF), and VEGF receptor 2 (VEGF-R2)].MethodsWe assessed the concentration changes of these proteins in 30 plasma and serum samples subjected to three, four, or five freeze–thaw cycles, and compared these with the concentration changes in the samples that were subjected to two freeze–thaw cycles before analysis.ResultsRepeated freezing and thawing by up to five cycles did not modify the plasma and serum concentrations of interferon-γ, IL-8, and VEGF-R2, while levels of MMP-7, tumor necrosis factor-α, and VEGF were significantly changed in both plasma and serum samples. Moreover, MMP-7 and VEGF concentrations tended to increase with freeze–thaw cycles. They were more elevated in plasma samples (up to about 15%) than in serum samples (up to about 7%), suggesting that serum is the preferred sample type for the analysis of circulating proteins.ConclusionThis is the first report on the effect of repeated freezing and thawing on plasma concentrations of MMP-7 and VEGF-R2. Our findings propose that researchers should consider the number of freeze–thaw cycles to select plasma or serum samples, depending on the type of analyte.

We evaluated the UF-100 flow cytometer (TOA Medical Electronics, Kobe, Japan) as a screening test for community-acquired urinary tract infection (UTI) to reduce the need for bacterial cultures. By comparing the test results for 330 urine samples with quantitative urine cultures, we established cutoff criteria for the UF-100. To rule out hospital-acquired UTI, all urine samples were from new patients who had not been admitted to a hospital within the previous month. Abacterial cutoff value of 3,000/microL provided the best discrimination for community-acquired UTI, with a sensitivity of 94.4% and a specificity of 73.4%compared with urine culture. It was possible to forgo 58.2% of cultures with only 4 false-negative results. With a bacterial cutoff value of 1,500/microL, the sensitivity improved to 100%, but the specificity declined to 49.8%, and only 38.5% of cultures could be avoided without any false-negative results. Screening with the UF-100 for community-acquired UTI is acceptable for routine use. It would improve the efficiency of the routine microbiology laboratory, and unnecessary antibiotic prescriptions could be reduced.

Introduction. The aim of this study was to differentiate between Candida famata and Candida guilliermondii correctly by using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and gene sequencing. Methods. Twenty-eight Candida strains from blood cultures that had been identified as C. famata (N = 25), C. famata/C. guilliermondii (N = 2), and C. guilliermondii (N = 1) by the VITEK 2 system using the YST ID card were included. We identified these strains by MALDI-TOF MS and gene sequencing using the 28S rRNA and ITS genes and compared the results with those obtained by the VITEK 2 system. Results. All 28 isolates were finally identified as C. guilliermondii. Sequencing analysis of the 28S rRNA gene showed 99.80%–100% similarity with C. guilliermondii for all 28 strains. The ITS gene sequencing of the strains showed 98.34%–100% homology with C. guilliermondii. By MALDI-TOF, we could correctly identify 21 (75%) of 28 C. guilliermondii isolates. Conclusion. We should suspect misidentification when C. famata is reported by the VITEK 2 system, and we always should keep in mind the possibility of misidentification of any organism when an uncommon species is reported.