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Previously, we have shown that mitochondrial transplantation in the sepsis model has immune modulatory effects. The mitochondrial function could have different characteristics dependent on cell types. Here, we investigated whether the effects of mitochondrial transplantation on the sepsis model could be different depending on the cell type, from which mitochondria were isolated. We isolated mitochondria from L6 muscle cells, clone 9 liver cells and mesenchymal stem cells (MSC). We tested the effects of mitochondrial transplantation using in vitro and in vivo sepsis models. We used the LPS stimulation of THP-1 cell, a monocyte cell line, as an in vitro model. First, we observed changes in mitochondrial function in the mitochondria-transplanted cells. Second, we compared the anti-inflammatory effects of mitochondrial transplantation. Third, we investigated the immune-enhancing effects using the endotoxin tolerance model. In the in vivo polymicrobial fecal slurry sepsis model, we examined the survival and biochemical effects of each type of mitochondrial transplantation. In the in vitro LPS model, mitochondrial transplantation with each cell type improved mitochondrial function, as measured by oxygen consumption. Among the three cell types, L6-mitochondrial transplantation significantly enhanced mitochondrial function. Mitochondrial transplantation with each cell type reduced hyper-inflammation in the acute phase of in vitro LPS model. It also enhanced immune function during the late immune suppression phase, as shown by endotoxin tolerance. These functions were not significantly different between the three cell types of origin for mitochondrial transplantation. However, only L6-mitochondrial transplantation significantly improved survival compared to the control in the polymicrobial intraabdominal sepsis model. The effects of mitochondria transplantation on both in vitro and in vivo sepsis models differed depending on the cell types of origin for mitochondria. L6-mitochondrial transplantation might be more beneficial in the sepsis model.

Background: Retrograde aortic root dissection toward the coronary ostium is uncommon, and acute myocardial ischemia is a potentially fatal condition in this situation. Repairing dissected coronary arteries to prevent myocardial malperfusion is difficult and we introduce our technique with case presentation. Case presentation: A 52-year-old male patient was admitted for acute type A aortic dissection. Circumferential detachment of the right coronary artery (RCA) ostium was detected intraoperatively. The proximal RCA was dissected, the intimal RCA was circumferentially detached with inner intussusception, and only adventitia was partially connected to the aortic root. Instead of performing coronary artery bypass grafting surgery to the RCA, direct RCA implantation to the ascending graft was performed after repairing the dissected lumen of the proximal RCA. Cardiopulmonary bypass weaning was smooth, and no complications related to the RCA were observed. Conclusion: Repairing dissected coronary artery at retrograde aortic root dissection is feasible option.

Immune suppression is known to occur during sepsis. Endotoxin tolerance is considered a mechanism of immune suppression in sepsis. However, the timing and serial changes in endotoxin tolerance have not been fully investigated. In this study, we investigated serial changes in endotoxin tolerance in a polymicrobial sepsis model. Herein, we used a rat model of fecal slurry polymicrobial sepsis. After induction of sepsis, endotoxin tolerance of peripheral blood mononuclear cells (PBMCs) and splenocytes was measured at various time points (6 h, 12 h, 24 h, 48 h, 72 h, 5 days, and 7 days), through the measurement of TNF-α production after stimulation with lipopolysaccharide (LPS) in an ex vivo model. At each time point, we checked for plasma tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 levels. Moreover, we analyzed reactive oxygen species (ROS) as measured by 2′,7′-dichlorodihydrofluorescein, plasma lactate, serum alanine aminotransferase (ALT), and creatinine levels. Nuclear factor (NF)-κB, IL-1 receptor-associated kinase (IRAK)-M, and cleaved caspase 3 levels were measured in the spleen. Endotoxin tolerance, measured by TNF-α production stimulated through LPS in PBMCs and splenocytes, was induced early in the sepsis model, starting from 6 h after sepsis. It reached a nadir at 24 to 48 h after sepsis, and then started to recover. Endotoxin tolerance was more prominent in the severe sepsis model. Plasma cytokines peaked at time points ranging from 6 to 12 h after sepsis. ROS levels peaked at 12 h and then decreased. Lactate, ALT, and serum creatinine levels increased up to 24 to 48 h, and then decreased. Phosphorylated p65 and IRAK-M levels of spleen increased up to 12 to 24 h and then decreased. Apoptosis was prominent 48 h after sepsis, and then recovered. In the rat model of polymicrobial sepsis, endotoxin tolerance occurred earlier and started to recover from 24 to 48 h after sepsis.

BACKGROUND AND AIMS Fat accumulation results from increased fat absorption and/or defective fat metabolism. Currently, the lipid-sensing nuclear receptor that controls fat utilization in hepatocytes is elusive. Liver X receptor alpha (LXRα) promotes accumulation of lipids through the induction of several lipogenic genes. However, its effect on lipid degradation is open for study. Here, we investigated the inhibitory role of LXRα in autophagy/lipophagy in hepatocytes and the underlying basis. APPROACH AND RESULTS In LXRα knockout mice fed a high-fat diet, or cell models, LXRα activation suppressed the function of mitochondria by inhibiting autophagy/lipophagy and induced hepatic steatosis. Gene sets associated with "autophagy" were enriched in hepatic transcriptome data. Autophagy flux was markedly augmented in the LXRα knockout mouse liver and primary hepatocytes. Mechanistically, LXRα suppressed autophagy-related 4B cysteine peptidase (ATG4B) and Rab-8B, responsible for autophagosome and -lysosome formation, by inducing let-7a and microRNA (miR)-34a. Chromatin immunoprecipitation assay enabled us to find LXRα as a transcription factor of let-7a and miR-34a. Moreover, 3' untranslated region luciferase assay substantiated the direct inhibitory effects of let-7a and miR-34a on ATG4B and Rab-8B. Consistently, either LXRα activation or the let-7a/miR-34a transfection lowered mitochondrial oxygen consumption rate and mitochondrial transmembrane potential and increased fat levels. In obese animals or nonalcoholic fatty liver disease (NAFLD) patients, let-7a and miR-34a levels were elevated with simultaneous decreases in ATG4B and Rab-8B levels. CONCLUSIONS LXRα inhibits autophagy in hepatocytes through down-regulating ATG4B and Rab-8B by transcriptionally activating microRNA let-7a-2 and microRNA 34a genes and suppresses mitochondrial biogenesis and fuel consumption. This highlights a function of LXRα that culminates in the progression of liver steatosis and steatohepatitis, and the identified targets may be applied for a therapeutic strategy in the treatment of NAFLD.

Activation of sterol regulatory element-binding protein 1 (SREBP-1), a master lipogenic transcription factor, is associated with cancer metabolism and metabolic disorders. Neddylation, the process of adding NEDD8 to its substrate, contributes to diverse biological processes. Here, we identified SREBP-1 as a substrate for neddylation by UBC12 and explored its impact on tumor aggressiveness. In cell-based assays, SREBP-1 neddylation prolonged SREBP-1 stability with a decrease in ubiquitination. Consequently, NEDD8 overexpression facilitated proliferation, migration, and invasion of SK-Hep1 liver tumor cells. MLN4924 (an inhibitor of the NEDD8-activating enzyme-E1) treatment or UBC12 knockdown prevented SREBP-1 neddylation and tumor cell phenotype change. This effect was corroborated in an in vivo xenograft model. In human specimens, SREBP-1, UBC12, and NEDD8 were all upregulated in hepatocellular carcinoma (HCC) compared to nontumorous regions. Moreover, SREBP-1 levels positively correlated with UBC12. In GEO database analyses, SREBP-1 levels were greater in metastatic HCC samples accompanying UBC12 upregulation. In HCC analysis, tumoral SREBP-1 and UBC12 levels discriminated overall patient survival rates. Additionally, MLN4924 treatment destabilized SREBP-1 in MDA-MB-231 breast cancer cells and in the tumor cell xenograft. SREBP-1 and UBC12 were also highly expressed in human breast cancer tissues. Moreover, most breast cancers with lymph node metastasis displayed predominant SREBP-1 and UBC12 expressions, which compromised overall patient survival rates. In summary, SREBP-1 is neddylated by UBC12, which may contribute to HCC and breast cancer aggressiveness through SREBP-1 stabilization, and these events can be intervented by MLN4924 therapy. Our findings may also provide potential reliable prognostic markers for tumor metastasis.

Hepatocellular carcinoma (HCC) is the second most common cancer worldwide, demonstrating aggressiveness and mortality more frequently in men than in women. Despite reports regarding the inhibitory ability of estrogen receptor alpha (ERα, ESR1) in certain cancer progression, targets and the basis of underlying gender disparity in HCC worsening remain elusive. Here, we report the ability of ERα to transcriptionally inhibit G protein subunit alpha 12 (Gα12) responsible for HCC worsening. First, using human samples and public database, the expression of ERα and Gα12 in HCC was examined. Then, quantitative real-time PCR, chromatin immunoprecipitation-assay, luciferase assay and immunoblottings of liver cancer cell lines confirmed the inhibitory ability of ERα on Gα12 and HCC progression. Gα12 promoted mesenchymal characteristics and amoeboidal movement, which was antagonized by ERα overexpression. Additionally, we found microRNA-141 and microRNA-200a as downstream targets of the Gα12 signaling axis for cancer malignancy regulation under the control of ERα. As for in-depth mechanism, PTP4A1 was found to be directly inhibited by microRNA-141 and microRNA-200a. Moreover, we found the inhibitory effect of ERα on amoeboidal movement by analyzing the morphology and blebbing of liver cancer cells and the active form of MLC levels. The identified targets and ESR1 levels are inversely correlated with human specimens, as well as with sex-biased survival rates of HCC patients. Collectively, ERα-dependent repression of Gα12 and consequent changes in the Gα12 signaling may explain the gender disparity in HCC, providing pharmacological clues for the control of metastatic HCC.

A prosthesis with a self-expanding nitinol frame firmly incorporates into the aortic wall and thus is difficult to explant. We introduce a novel technique that simplifies explantation.

Left ventricular lipoma is a rare intracardiac tumour that is usually resected through sternotomy to effectively explore the left ventricular cavity. We introduce a simple technique to expose the left ventricular cavity and resect the intraventricular lipoma using a rolled up flexible ruler through right mini-thoracotomy. Imaging studies and gross and microscopic photography of intraventricular lipoma are presented in this report.

The muscular discontinuities at the pulmonary vein (PV)–left atrial (LA) junction are known. The high-density mapping may help to find the muscular discontinuity. This study evaluated the efficacy of a partial antral ablation for a pulmonary vein (PV) isolation using high density (HD) mapping. A total of 60 drug-refractory atrial fibrillation (AF) patients undergoing catheter ablation were enrolled. The detailed activation mapping of each PV and LA junction was performed using an HD mapping system, and each PV segment’s activation pattern was classified into a “directly-activated from the LA” or “passively-activated from an adjacent PV segment” pattern. The antral ablations were performed at the directly-activated PV segments only when the PV had “passively-activated segments”. If the PV did not contain passively-activated segments, a circumferential antral ablation was performed on those PVs. A “successful partial antral ablation” was designated if the electrical isolation of targeted PV was achieved by ablation at the directly-activated segments only. If the isolation was not achieved even though all directly-activated segments were ablated, a “failed partial antral ablation” was designated, and then a circumferential ablation was performed. Among 240 PVs, passively-activated segments were observed in 140 (58.3%) PVs. Both inferior PVs had more passively-activated segments than superior PVs, and the posteroinferior segments had the highest proportion of passive activation. The overall rate of successful partial antral ablation was 85%. The atrial tachyarrhythmia recurrence was observed in 10 patients (16.7%) at 1-year. HD mapping allowed the evaluation of the detailed activation patterns of the PVs, and passively-activated segments may represent muscular discontinuity. Partial antral ablation of directly-activated antral segments only was feasible and effective for a PVI.

A mild-to-moderate aortic root aneurysm might be overlooked during the assessment of the donor heart. The use of the Z-score in such cases may be helpful in guiding clinical decision-making. To make a diagnosis of genetic aortopathy, a genetic panel study and matching with clinical criteria such as Ghent nosology are essential. Valve-sparing root reimplantation may be a viable option in cases with aortic root aneurysm developing after heart transplant.

Background The injured liver loses normal function, with concomitant decrease of key identity genes. Super-enhancers contribute to mammalian cell identity. Here, we identified core transcription factors (TFs) that are active in hepatocytes, using genome-wide analysis and hierarchical ordering of super-enhancer distribution. Methods Expression of core TFs was assessed in a cohort of patients with hepatitis or cirrhosis and animal models. Quantitative PCR, chromatin immunoprecipitation assays, and hydrodynamic gene delivery methods were used to assess gene regulation and hepatocyte viability. RNA-sequencing data were generated to investigate the role of LRH1 in hepatocyte protection from injury. Results Network analysis of super-enhancer-associated gene interactions and expression arrays for cohorts of patients with hepatitis and cirrhosis enabled us to identify a super-enhancer-associated network, and LRH1, HNF4α, PPARα, and RXRα as core TFs. In mouse models, expression of core TFs was robustly inhibited by single and multiple challenge(s) with liver toxicant. RNA-seq analysis revealed changes in expression in the super-enhancer-associated genes sensitively biased toward repression by intoxication. LRH1 gene delivery prevented the loss of hepatic super-enhancer-associated signaling circuitry in toxicant-challenged mice, and protected the liver from injury, indicating the role of LRH1 in hepatocyte identity and viability. In hepatocytes, overexpression of each core TF promoted induction of other TFs. Conclusion Overall, this study identified LRH1-driven pathway as a circuitry responsible for hepatocyte identity by using cistromic analysis, improving our understanding of liver pathophysiology and identifying novel therapeutic targets.

Background: Takotsubo syndrome following cardiac surgery is a rare occurrence. However, early diagnosis is essential to prevent treatment which could increase the left ventricular outflow tract pressure gradient in patients with Takotsubo syndrome, and lead to cardiogenic shock. Therefore, our study aimed to identify the incidence of Takotsubo syndrome after cardiopulmonary bypass and the associated risk factors and prognosis.Methods: We retrospectively studied 5,773 patients who underwent cardiopulmonary bypass between February 2007 and July 2017. Among these, Takotsubo syndrome was diagnosed in 52 (0.9%). To evaluate the risk factors for Takotsubo syndrome, 104 of the remaining 5,721 patient were randomly selected as the control group (1:2 ratio). Univariate and multivariate logistic regression analyses were used for risk factor analysis. Results: Majority of patients (69.2%) in the Takotsubo syndrome group underwent mitral valve surgery, compared to 32.7% in the control group. The following risk factors of Takotsubo syndrome were identified: atrio-ventricular valve surgery (odds ratio (OR),10.5; 95% confidence interval (CI), 2.6-42.5; P=0.001); and the immediate postoperative use of epinephrine (OR, 3.3; 95%CI, 1.0-10.7; P=0.05) and dobutamine (OR, 4.8; 95%CI, 1.72-13.3; P=0.003). Hypertension was a significant protective factor against Takotsubo syndrome following cardiac surgery (OR, 0.22; 95%CI, 0.06-0.73; P=0.01).Conclusions: Takotsubo syndrome following cardiac surgery is rare. Immediate postoperative use of epinephrine and doputamine, as well as atrio-ventricular valve surgery were factors associated with the development of Takotsubo syndrome.

INTRODUCTION Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) catheter ablation. However, a PVI alone has been considered insufficient for persistent AF. This study aimed to evaluate the efficacy of persistent AF ablation targeting complex fractionated atrial electrogram (CFAE) areas within low voltage zones identified by high-resolution mapping in addition to the PVI. METHODS We randomized 50 patients (mean age 58.4 ± 9.5 years old, 86.0% males) with persistent AF to a PVI + CFAE group and PVI only group in a 1:1 ratio. CFAE and voltage mapping was performed simultaneously using a Pentaray Catheter with the CARTO3 CONFIDENSE module (Biosense Webster, CA, USA). The PVI + CFAE group, in addition to the PVI, underwent ablation targeting low voltage areas (

Background and Purpose Hepatocellular carcinoma (HCC) is the second most common cancer worldwide, demonstrating aggressiveness and mortality more frequently in men than in women. Despite reports regarding the inhibitory ability of estrogen receptor alpha (ERα, ESR1) in certain cancer progression, targets and the basis of underlying gender disparity in HCC worsening remain elusive. Experimental Approach Human HCC samples were used for immunoblottings and immunohistochemistry. Estradiol (E2) was treated to HCC cell lines and were evaluated by immunoblottings, polymerase chain reaction, immunofluorescence, and live imaging. Key Results Here, we report the ability of ERα to transcriptionally inhibit G protein subunit alpha 12 (Gα12). First, using human samples and public database, the expression of ERα and Gα12 in HCC was examined. Then, quantitative real-time PCR, chromatin immunoprecipitation-assay, luciferase assay, and immunoblottings confirmed the inhibitory ability of ERα on Gα12 and EMT. Additionally, we found microRNA-141 and -200a as downstream targets of the Gα12 signaling axis for cancer malignancy regulation under the control of ERα. As for in-depth mechanism, PTP4A1 was found to be directly inhibited by microRNA-141 and -200a. Gα12 and PTP4A1 promoted epithelial-mesenchymal transition, as well as mesenchymal to amoeboidal transition, antagonized by ERα modulations. Conclusion and Implications The identified targets and ESR1 levels inversely correlated in human specimens, as well as with sex-biased survival rates of HCC patients. Collectively, ERα-dependent repression of Gα12 and consequent changes in the Gα12 signaling may explain the gender disparity in HCC, providing pharmacological clues for the control of metastatic HCC.

Highlights • 19 patients (24%) were treated with ECMO among 80 mechanical ventilation-supported patients. • Weaning and mortality rate of ECMO was 42% (8/19) and 58% (10/19), respectively. • Despite the known low case-fatality rate of COVID-19, mortality rate of ECMO-treated patients was substantial., Background The COVID-19 pandemic has caused an epidemic of critical patients, some of whom have been treated with extracorporeal membrane oxygenation (ECMO). This purpose of study is to describe the clinical course of COVID-19 patients treated with ECMO. Methods A multicentered study of critical patients with COVID-19 treated at six hospitals in Daegu was conducted between January and April 2020. Results Among the 80 patients receiving mechanical ventilation support, 19 (24%) were treated with ECMO included (median age 63.0 years). Eight of the 19 patients (42%) were weaned off ECMO (9.8 days, IQR 7.0-13.7). Among them, four patients were also weaned off mechanical ventilation (33.4 days, IQR 29.3 - 35.7), three were still receiving mechanical ventilation (50.9 days), and one expired after ECMO weaning. According to the univariate analysis, the factor that was associated with successful ECMO weaning was vitamin B12 treatment (p = 0.028). Conclusions During the COVID-19 epidemic, ECMO weaning and mortality rates were 42% and 58%, respectively.

Two sediment core samples from the brackish Lake Nakaumi in Japan were analyzed to determine the historical profiles of organochlorine pesticides (OCPs). It was observed that from the 1940s to 2005, the vertical distribution of OCPs in sediment cores reflected the temporal trend of pesticide usage in Japan. Dichlorodiphenyltrichloroethane (DDT) and its metabolites were predominant, with concentrations of 0.008-8.27 ng g

Background & Aims Hepatic stellate cells (HSCs) have a role in liver fibrosis. Guanine nucleotide-binding α-subunit 12 (Gα 12 ) converges signals from G-protein-coupled receptors whose ligand levels are elevated in the environment during liver fibrosis; however, information is lacking on the effect of Gα 12 on HSC trans -differentiation. This study investigated the expression of Gα 12 in HSCs and the molecular basis of the effects of its expression on liver fibrosis. Methods Gα 12 expression was assessed by immunostaining, and immunoblot analyses of mouse fibrotic liver tissues and primary HSCs. The role of Gα 12 in liver fibrosis was estimated using a toxicant injury mouse model with Gα 12 gene knockout and/or HSC-specific Gα 12 delivery using lentiviral vectors, in addition to primary HSCs and LX-2 cells using microRNA (miR) inhibitors, overexpression vectors, or adenoviruses. miR-16, Gα 12 , and LC3 were also examined in samples from patients with fibrosis. Results Gα 12 was overexpressed in activated HSCs and fibrotic liver, and was colocalised with desmin. In a carbon tetrachloride-induced fibrosis mouse model, Gα 12 ablation prevented increases in fibrosis and liver injury. This effect was attenuated by HSC-specific lentiviral delivery of Gα 12 . Moreover, Gα 12 activation promoted autophagy accompanying c-Jun N-terminal kinase-dependent ATG12-5 conjugation. In addition, miR-16 was found to be a direct inhibitor of the de novo synthesis of Gα 12 . Modulations of miR-16 altered autophagy in HSCs. In a fibrosis animal model or patients with severe fibrosis, miR-16 levels were lower than in their corresponding controls. Consistently, cirrhotic patient liver tissues showed Gα 12 and LC3 upregulation in desmin-positive areas. Conclusions miR-16 dysregulation in HSCs results in Gα 12 overexpression, which activates HSCs by facilitating autophagy through ATG12-5 formation. This suggests that Gα 12 and its regulatory molecules could serve as targets for the amelioration of liver fibrosis. Lay summary Guanine nucleotide-binding α-subunit 12 (Gα 12 ) is upregulated in activated hepatic stellate cells (HSCs) as a consequence of the dysregulation of a specific microRNA that is abundant in HSCs, facilitating the progression of liver fibrosis. This event is mediated by c-Jun N-terminal kinase-dependent ATG12-5 formation and the promotion of autophagy. We suggest that Gα 12 and its associated regulators could serve as new targets in HSCs for the treatment of liver fibrosis.

In this study, dust explosion experiments were conducted to investigate the explosion characteristics of three samples of dust from wood particleboard that had exploded in the manufacturing process. Explosion tests were conducted by utilizing a standardized Siwek 20L apparatus according to the standardized test procedures in the European Standard CEN EN 14034 series and CEN EN 13821. To understand the physiochemical properties of the tested dust samples, the element composition, particle size distribution, and heat release rate were obtained by utilizing an element analyzer, particle-size analyzer, and cone calorimeter, respectively. Explosion pressure and rising explosion pressure featured log-linearly increasing trends in dust concentration and equivalence ratios until the maximum. They then decreased linearly as the dust concentration and equivalence ratios increased. Dust particles of smaller sizes and non-spherical shapes achieved higher maximum explosion pressure and maximum explosion pressure rising rates. The dust concentration at maximum explosion pressure decreased as the dust particle size decreased. Thermal decomposition rates and mass loss rates of dusts, which were calculated from the results of the cone calorimeter test, were mainly affected by the content of noncombustible materials such as nitrogen and inorganic residuals. To suggest a proper method to analyze dust explosion characteristics, the correlations among the tested dust samples were calculated with four variables: dust concentration, equivalence ratio, equivalence ratio based on thermal decomposition rate, and mass loss rate. The results showed that the latter two variables were considered to be more proper methods than the dust concentration and showed slightly better correlation than the equivalence ratio. A bubble graph and a contour diagram of the explosion pressure were also utilized to visualize the degree of explosion risk and to determine a safe region of operation. The test results and analytical methods proposed in this study could be utilized to design methods for the prediction, prevention, and protection of dust explosions.