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Germinal centers (GCs) are microanatomic structures that develop in secondary lymphoid organs in response to antigenic stimulation. Within GCs B cells clonally expand and their immunoglobulin genes undergo class switch recombination and somatic hypermutation. Transcriptional profiling has identified a number of genes that are prominently expressed in GC B cells. Among them is Rgs13, which encodes an RGS protein with a dual function. Its canonical function is to accelerate the intrinsic GTPase activity of heterotrimeric G-protein α subunits at the plasma membrane, thereby limiting heterotrimeric G-protein signaling. A unique, non-canonical function of RGS13 occurs following translocation to the nucleus, where it represses CREB transcriptional activity. The functional role of RGS13 in GC B cells is unknown. To create a surrogate marker for Rgs13 expression and a loss of function mutation, we inserted a GFP coding region into the Rgs13 genomic locus. Following immunization GFP expression rapidly increased in activated B cells, persisted in GC B cells, but declined in newly generated memory B and plasma cells. Intravital microscopy of the inguinal lymph node (LN) of immunized mice revealed the rapid appearance of GFP+ cells at LN interfollicular regions and along the T/B cell borders, and eventually within GCs. Analysis of WT, knock-in, and mixed chimeric mice indicated that RGS13 constrains extra-follicular plasma cell generation, GC size, and GC B cell numbers. Analysis of select cell cycle and GC specific genes disclosed an aberrant gene expression profile in the Rgs13 deficient GC B cells. These results indicate that RGS13, likely acting at cell membranes and in nuclei, helps coordinate key decision points during the expansion and differentiation of naive B cells. [ABSTRACT FROM AUTHOR]

Background: A substantial number of patients presenting with non-ST-elevation myocardial infarction (NSTEMI) and multivessel disease (MVD) have severe left ventricular systolic dysfunction (LVSD) (left ventricular ejection fraction (LVEF) less than 35%). But data are lacking regarding optimal percutaneous coronary intervention (PCI) strategy for these patients. The aim of this study was to compare the long-term outcomes of IRA (infarct-related artery)-only and multivessel PCI in patients with NSTEMI and MVD complicated by severe LVSD. Methods: Among 13,104 patients enrolled in the PCI registry from November 2011 to December 2015, patients with NSTEMI and MVD with severe LVSD who underwent successful PCI were screened. The primary outcome was 3-year major adverse cardiovascular events (MACEs), defined as all-cause death, any myocardial infarction, stroke, and any revascularization. Results: Overall, 228 patients were treated with IRA-only PCI (n = 104) or MV-PCI (n = 124). The MACE risk was significantly lower in the MV-PCI group than in the IRA-only PCI group (35.5% vs. 54.8%; hazard ratio [HR] 0.561; 95% confidence interval [CI] 0.378–0.832; p = 0.04). This result was mainly driven by a significantly lower risk of all-cause death (23.4% vs. 41.4%; hazard ratio [HR] 0.503; 95% confidence interval [CI] 0.314–0.806; p = 0.004). The results were consistent after multivariate regression, propensity-score matching, and inverse probability weighting to adjust for baseline differences. Conclusions: Among patients with NSTEMI and MVD complicated with severe LVSD, multivessel PCI was associated with a significantly lower MACE risk. The findings may provide valuable information to physicians who are involved in decision-making for these patients. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to develop and validate deep-learning-based artificial intelligence algorithm for predicting mortality of AHF (DAHF). Methods and results: 12,654 dataset from 2165 patients with AHF in two hospitals were used as train data for DAHF development, and 4759 dataset from 4759 patients with AHF in 10 hospitals enrolled to the Korean AHF registry were used as performance test data. The endpoints were in-hospital, 12-month, and 36-month mortality. We compared the DAHF performance with the Get with the Guidelines–Heart Failure (GWTG-HF) score, Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) score, and other machine-learning models by using the test data. Area under the receiver operating characteristic curve of the DAHF were 0.880 (95% confidence interval, 0.876–0.884) for predicting in-hospital mortality; these results significantly outperformed those of the GWTG-HF (0.728 [0.720–0.737]) and other machine-learning models. For predicting 12- and 36-month endpoints, DAHF (0.782 and 0.813) significantly outperformed MAGGIC score (0.718 and 0.729). During the 36-month follow-up, the high-risk group, defined by the DAHF, had a significantly higher mortality rate than the low-risk group(p<0.001). Conclusion: DAHF predicted the in-hospital and long-term mortality of patients with AHF more accurately than the existing risk scores and other machine-learning models. [ABSTRACT FROM AUTHOR]

Objectives: Beneficial effects of overweight and obesity on mortality after acute myocardial infarction (AMI) have been described as “Body Mass Index (BMI) paradox”. However, the effects of BMI is still on debate. We analyzed the association between BMI and 1-year clinical outcomes after AMI. Methods: Among 13,104 AMI patients registered in Korea Acute Myocardial Infarction Registry-National Institute of Health (KAMIR-NIH) between November 2011 and December 2015, 10,568 patients who eligible for this study were classified into 3 groups according to BMI (Group 1; < 22 kg/m2, 22 ≤ Group 2 < 26 kg/m2, Group 3; ≥ 26 kg/m2). The primary end point was all cause death at 1 year. Results: Over the median follow-up of 12 months, the event of primary end point occurred more frequently in the Group 1 patients than in the Group 3 patients (primary endpoint: adjusted hazard ratio [aHR], 1.537; 95% confidence interval [CI] 1.177 to 2.007, p = 0.002). Especially, cardiac death played a major role in this effect (aHR, 1.548; 95% confidence interval [CI] 1.128 to 2.124, p = 0.007). Conclusions: Higher BMI appeared to be good prognostic factor on 1-year all cause death after AMI. This result suggests that higher BMI or obesity might confer a protective advantage over the life-quality after AMI. [ABSTRACT FROM AUTHOR]

Background: We investigated the role of nutritional risk index (NRI) in predicting 1-year mortality in patients with acute decompensated heart failure (ADHF). Methods: Among 5,625 cohort patients enrolled in Korean Acute Heart Failure (KorAHF) Registry, a total of 5,265 patients who were possible to calculate NRI [NRI = (1.519 x serum albumin [g/dl]) + (41.7 x weight [kg]/ideal body weight [kg])] were enrolled. The patients were divided into 4 groups according to the NRI quartile; Q1 <89 (n = 1121, 69.9 ± 14.5 years, 632 males), Q2 89–95 (n = 1234, 69.7 ± 14.4 years, 677 males), Q3 95–100 (n = 1199, 68.8 ± 14.0 years, 849 males), Q4 >100 (n = 1711, 65.6 ± 14.5 years, 779 males). Primary end-point was all-cause mortality at 1-year clinical follow-up. Results: The 1-year mortality was significantly increased as the NRI quartile decreased, and the lowest NRI quartile was associated with the highest 1-year mortality (Q1: 27.5% vs. Q2: 20.9% vs. Q3: 12.9% vs. Q4: 8.7%, linear p <0.001). On Kaplan-Meier survival analysis, the significant inter-quartile difference was observed (p <0.001 for all). In multivariate analysis using Cox proportional hazard regression, the lowest NRI quartile was an independent predictor of 1-year mortality in patients with ADHF. Conclusions: Poor nutritional status as assessed by NRI and quartile grading of NRI was associated with 1-year mortality in Korean patients with ADHF. The assessment of nutritional status by NRI may provide additional prognostic information and thus would be useful in the risk stratification of the patients with ADHF. [ABSTRACT FROM AUTHOR]

Plant genetic engineering, which has led to the production of plant-derived monoclonal antibodies (mAbPs), provides a safe and economically effective alternative to conventional antibody expression methods. In this study, the expression levels and biological properties of the anti-rabies virus mAbP SO57 with or without an endoplasmic reticulum (ER)-retention peptide signal (Lys-Asp-Glu-Leu; KDEL) in transgenic tobacco plants (Nicotiana tabacum) were analyzed. The expression levels of mAbP SO57 with KDEL (mAbPK) were significantly higher than those of mAbP SO57 without KDEL (mAbP) regardless of the transcription level. The Fc domains of both purified mAbP and mAbPK and hybridoma-derived mAb (mAbH) had similar levels of binding activity to the FcγRI receptor (CD64). The mAbPK had glycan profiles of both oligomannose (OM) type (91.7%) and Golgi type (8.3%), whereas the mAbP had mainly Golgi type glycans (96.8%) similar to those seen with mAbH. Confocal analysis showed that the mAbPK was co-localized to ER-tracker signal and cellular areas surrounding the nucleus indicating accumulation of the mAbP with KDEL in the ER. Both mAbP and mAbPK disappeared with similar trends to mAbH in BALB/c mice. In addition, mAbPK was as effective as mAbH at neutralizing the activity of the rabies virus CVS-11. These results suggest that the ER localization of the recombinant mAbP by KDEL reprograms OM glycosylation and enhances the production of the functional antivirus therapeutic antibody in the plant. [ABSTRACT FROM AUTHOR]