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Background and Objectives Determination of the anti-A/-B titre pre-and posttransplantation is beneficial for treatment selection. Currently, the recommended method for antibody titration is the tube test (TT) assay. Dithiothreitol (DTT) is used for IgM antibody inactivation. Recently, a fully automated antibody titration assay using the column agglutination technique (CAT) was developed (auto-CAT). Our aim was to compare the auto-CAT and TT techniques for ABO antibody titration, to evaluate the effectiveness of DTT-treated plasma for use with auto-CAT and to define the cut-off value for antibody titration by auto-CAT. Materials and MethodsWe enrolled 30 healthy individuals, including 10 each for blood types A, B and O. We performed antibody titre measurement using the TT technique and auto-CAT simultaneously. Auto-CAT uses the bead column agglutination technology. ResultsWith the auto-CAT cut-off value set to weak (w)+ with DTT treatment plasma, the concordance rate was 45%, and the weighted kappa value between TT and auto-CAT results was 0Á994 in all subjects. Furthermore, there was a significant positive correlation between the anti-A/-B titre results obtained using the TT technique and auto-CAT in all blood types. Moreover, a positive bias (falsely elevated end-points due to agglomeration of A/B cells) was not observed in auto-CAT testing using DTT-treated plasma.Conclusion Our results show that 1+ agglutination using the TT technique is equivalent to w+ agglutination obtained using auto-CAT. We recommend that DTT may be used with auto-CAT to measure antibody titres. Thus, we suggest that auto-CAT is useful for antibody titration in routine examination.

In an attempt to characterize proteins secreted by the corpus luteum, explant cultures of luteal slices from cows taken on Days 3, 7, 11, 14, 17, and 19 of the estrous cycle, and Days 17, 88, 180, and > 240 of pregnancy were incubated with H-leucine for 24 h. Proteins in luteal-conditioned medium were separated by two-dimensional PAGE, transferred to polyvinylidene fluoride membrane, and subjected to N-terminal amino acid microsequencing. Microsequence analysis revealed that the bovine corpus luteum synthesized and released de novo synthesized apolipoproteins (Apo) E and A-I in culture during the estrous cycle and pregnancy. Release of Apo E was observed only on Day 3 of the estrous cycle. Release of Apo A-I was observed on Days 11, 14, 17, and 19 of the estrous cycle, and on all days of pregnancy examined. To demonstrate the presence of the appropriate mRNA and characterize the temporal relationship for these identified proteins, total RNA was isolated from corpora lutea on Days 2, 3, 7, 16, 17, and 20 of the estrous cycle, and on Days 17, 90, 170, 180, and 272 of pregnancy, and submitted to Northern and dot blot analysis. Apo E mRNA was expressed only on Days 2-3 of the estrous cycle and was not expressed on the other days of the cycle or during pregnancy. A single Apo E mRNA transcript about 1.0 kilobase (kb) in size was observed. Expression of Apo A-I mRNA was detected on all days of the estrous cycle and pregnancy examined. Apo A-I cDNA hybridized with a single mRNA transcript about 1.0 kb in size. Apo A-I mRNA levels did not differ among days of the estrous cycle, although higher levels of Apo A-I mRNA were observed during later stages of pregnancy. Serum concentrations of Apo A-I and progesterone were correlated across the estrous cycle but not during the prepartum period or after parturition. This study demonstrates for the first time that the corpus luteum synthesizes Apo E and Apo A-I and expresses their respective mRNAs. The pattern of expression of Apo E and Apo A-I mRNAs paralleled that of de novo synthesis of their respective proteins after incubation of luteal tissue with [H]leucine. The role of luteal apolipoproteins may involve an autocrine/paracrine function influencing luteal development, tissue remodeling, and steroidogenesis.

The QT variability index (QTVI), which measures the instability of myocardial repolarization, is usually calculated from a single electrocardiogram (ECG) recording and can be easily applied in children. It is well known that frequency analysis of heart rate variability (HRV) can detect autonomic balance, but it is not clear whether QTVI is correlated with autonomic tone. Therefore, we evaluated the association between QTVI and HRV to elucidate whether QTVI is correlated with autonomic nerve activity. Apparently, healthy 320 children aged 0–7 years who visited Fujita Health University Hospital for heart checkup examinations were included. The RR and QT intervals of 60 continuous heart beats were measured, and the QTVI was calculated using the formula of Berger et al. Frequency analysis of HRV, including the QTVI analysis region, was conducted for 2 min and the ratio of low-frequency (LF) components to high-frequency (HF) components (LF/HF) and HF/(LF + HF) ratio was calculated as indicators of autonomic nerve activity. Then, the correlations between QTVI and these parameters were assessed. QTVI showed a significant positive correlation with LF/HF ratio (r = 0.45, p < 0.001) and negative correlation with HF/(LF + HF) ratio (r = −0.429, p < 0.001). These correlations remained after adjustment for sex and age. QTVI, which is calculated from non-invasive ECG and can detect abnormal myocardial repolarization, is significantly correlated with frequency analysis of HRV parameters. QTVI reflects autonomic nerve balance in children.

JTp can be used to evaluate the variability of the repolarization time in healthy infants, and may be useful for detection of early repolarization abnormalities.