Differential DNA methylation landscape of miRNAs genes in mice liver fibrosis

BACKGROUND

Patients with chronic liver disease were found nearly all to have liver fibrosis, which is characterized by excess accumulation of extracellular matrix (ECM) proteins. While ECM accumulation can prevent liver infection and injury, it can destroy normal liver function and architecture. miRNA's own regulation was involved in DNA methylation change. The purpose of this study is to detect DNA methylation landscape of miRNAs genes in mice liver fibrosis tissues.

METHODS

Male mice (10-12 weeks) were injected CCl4 from abdominal cavity to induced liver fibrosis. 850 K BeadChips were used to examine DNA methylation change in whole genome. The methylation change of 16 CpG dinucleotides located in promoter regions of 4 miRNA genes were detected by bisulfite sequencing polymerase chain reaction (BSP) to verify chip data accuracy, and these 4 miRNA genes' expressions were detected by RT-qPCR methods.

RESULTS

There are 769 differential methylation sites (DMS) in total between fibrotic liver tissue and normal mice liver tissue, which were related with 148 different miRNA genes. Chips array data were confirmed by bisulfite sequencing polymerase chain reaction (R = 0.953; P < 0.01). GO analysis of the target genes of 2 miRNA revealed that protein binding, cytoplasm and chromatin binding activity were commonly enriched; KEGG pathway enrichment analysis displayed that TGF-beta signaling pathway was commonly enriched.

CONCLUSION

The DNA of 148 miRNA genes was found to have methylation change in liver fibrosis tissue. These discoveries in miRNA genes are beneficial to future miRNA function research in liver fibrosis.

Neutrophil ALDH2 is a new therapeutic target for the effective treatment of sepsis-induced ARDS

Acetaldehyde dehydrogenase 2 (ALDH2) mutations are commonly found in a subgroup of the Asian population. However, the role of ALDH2 in septic acute respiratory distress syndrome (ARDS) remains unknown. Here, we showed that human subjects carrying the ALDH2rs671 mutation were highly susceptible to developing septic ARDS. Intriguingly, ALDH2rs671-ARDS patients showed higher levels of blood cell-free DNA (cfDNA) and myeloperoxidase (MPO)-DNA than ALDH2WT-ARDS patients. To investigate the mechanisms underlying ALDH2 deficiency in the development of septic ARDS, we utilized Aldh2 gene knockout mice and Aldh2rs671 gene knock-in mice. In clinically relevant mouse sepsis models, Aldh2-/- mice and Aldh2rs671 mice exhibited pulmonary and circulating NETosis, a specific process that releases neutrophil extracellular traps (NETs) from neutrophils. Furthermore, we discovered that NETosis strongly promoted endothelial destruction, accelerated vascular leakage, and exacerbated septic ARDS. At the molecular level, ALDH2 increased K48-linked polyubiquitination and degradation of peptidylarginine deiminase 4 (PAD4) to inhibit NETosis, which was achieved by promoting PAD4 binding to the E3 ubiquitin ligase CHIP. Pharmacological administration of the ALDH2-specific activator Alda-1 substantially alleviated septic ARDS by inhibiting NETosis. Together, our data reveal a novel ALDH2-based protective mechanism against septic ARDS, and the activation of ALDH2 may be an effective treatment strategy for sepsis.

Sex differences in the management of patients with suspected acute coronary syndrome in China

Few studies have assessed sex differences in the management of suspected acute coronary syndrome (ACS). We aimed to compare the evaluation, treatment, and outcomes between males and females with suspected ACS in the emergency department. Data were obtained from a prospective registry of acute chest pain involving 21 emergency departments in Shandong Province, China. The primary endpoint was 30-day major adverse cardiac events (MACEs). Overlap propensity score weighting was used to address potential confounding. A total of 8046 patients were analysed (42.8% female). Overlap-weighted analysis showed no significant association of female sex with 30-day MACEs (odds ratio, 0.91; 95% CI 0.75 to 1.11; P = 0.363). Secondary analyses found that women were less likely to be identified as high risk at first presentation (odds ratio, 0.86; 95% CI 0.78 to 0.94; P < 0.001). In the emergency department, women were less likely to undergo antiplatelet therapy (odds ratio, 0.87; 95% CI 0.79 to 0.96; P = 0.004) or coronary angiography (odds ratio, 0.78; 95% CI, 0.69 to 0.88; P < 0.001). Women had a longer length of stay in the emergency department and were less likely to be admitted to a ward at disposition. These sex differences existed only in the non-ST-elevation subgroup and were independent of risk stratification. Women with non-ST-elevation chest pain in China received suboptimal treatment in the emergency department. However, their clinical outcomes were not significantly different from those of men. Further studies are needed to determine the causes and impacts of these sex differences.

Magnetocardiography-based coronary artery disease severity assessment and localization using spatiotemporal features

Objective.This study aimed to develop an automatic and accurate method for severity assessment and localization of coronary artery disease (CAD) based on an optically pumped magnetometer magnetocardiography (MCG) system.Approach.We proposed spatiotemporal features based on the MCG one-dimensional signals, including amplitude, correlation, local binary pattern, and shape features. To estimate the severity of CAD, we classified the stenosis as absence or mild, moderate, or severe cases and extracted a subset of features suitable for assessment. To localize CAD, we classified CAD groups according to the location of the stenosis, including the left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA), and separately extracted a subset of features suitable for determining the three CAD locations.Main results.For CAD severity assessment, a support vector machine (SVM) achieved the best result, with an accuracy of 75.1%, precision of 73.9%, sensitivity of 67.0%, specificity of 88.8%, F1-score of 69.8%, and area under the curve of 0.876. The highest accuracy and corresponding model for determining locations LAD, LCX, and RCA were 94.3% for the SVM, 84.4% for a discriminant analysis model, and 84.9% for the discriminant analysis model.Significance. The developed method enables the implementation of an automated system for severity assessment and localization of CAD. The amplitude and correlation features were key factors for severity assessment and localization. The proposed machine learning method can provide clinicians with an automatic and accurate diagnostic tool for interpreting MCG data related to CAD, possibly promoting clinical acceptance.

SUPER Score Contributes to Warning and Management in Early-Stage COVID-19

Background

Some COVID-19 patients deteriorate to severe cases with relatively higher case-fatality rates, which increases the medical burden. This necessitates identification of patients at risk of severe disease. Early assessment plays a crucial role in identifying patients at risk of severe disease. This study is to assess the effectiveness of SUPER score as a predictor of severe COVID-19 cases.

Methods

We consecutively enrolled COVID-19 patients admitted to a comprehensive medical center in Wuhan, China, and recorded clinical characteristics and laboratory indexes. The SUPER score was calculated using parameters including oxygen saturation, urine volume, pulse, emotional state, and respiratory rate. In addition, the area under the receiver operating characteristic curve (AUC), specificity, and sensitivity of the SUPER score for the diagnosis of severe COVID-19 were calculated and compared with the National Early Warning Score 2 (NEWS2).

Results

The SUPER score at admission, with a threshold of 4, exhibited good predictive performance for early identification of severe COVID-19 cases, yielding an AUC of 0.985 (95% confidence interval [CI] 0.897-1.000), sensitivity of 1.00 (95% CI 0.715-1.000), and specificity of 0.92 (95% CI 0.775-0.982), similar to NEWS2 (AUC 0.984; 95% CI 0.895-1.000, sensitivity 0.91; 95% CI 0.587-0.998, specificity 0.97; 95% CI 0.858-0.999). Compared with patients with a SUPER score<4, patients in the high-risk group exhibited lower lymphocyte counts, interleukin-2, interleukin-4 and higher fibrinogen, C-reactive protein, aspartate aminotransferase, and lactate dehydrogenase levels.

Conclusions

In conclusion, the SUPER score demonstrated equivalent accuracy to the NEWS2 score in predicting severe COVID-19. Its application in prognostic assessment therefore offers an effective early warning system for critical management and facilitating efficient allocation of health resources.

Electrical-mechanical dynamical coupling between electrocardiographic and photoplethysmographic signals during cardiopulmonary resuscitation

BACKGROUND AND OBJECTIVE

Cardiac arrest (CA) remains a significant cause of death and disability. High-quality cardiopulmonary resuscitation (CPR) can improve the survival rate of CA. A challenging issue is to find physiological indicators for screening and evaluating the cardiovascular function associated with CPR. This study aimed to investigate the electrical-mechanical dynamic coupling between electrocardiographic (ECG) and photoplethysmographic (PPG) signals for indicating cardiovascular function in the progress of CPR.

METHOD

The ECG and PPG signals were simultaneously collected from a porcine CA model (n = 10) induced by ventricular fibrillation, and were further divided into four periods: Baseline, CA, CPR, and recovery of spontaneous circulation (ROSC). Recurrence quantitative analysis (RQA) was applied to examine the nonlinear dynamics of the ECG and PPG signals individually, and cross recurrence quantitative analysis (CRQA) was used to examine the ECG-PPG dynamical coupling.

RESULTS

The CA influenced the dynamic patterns of electrical and mechanical activities and the electrical-mechanical coupling, which can be observed from the reduced entropy (ENTR) (p < 0.01), reduced determinism (DET) (p < 0.01) and reduced trapping time (TT) (p < 0.01) at CA compared to Baseline. The recurrence rate (RR), ENTR, DET, and TT at CPR were significantly lower than the parameters at ROSC but higher than those at CA.

CONCLUSIONS

The electrical-mechanical dynamical coupling was sensitive to CPR and able to reflect the changes in cardiac function in the process of CPR.

Co-registration of OPM-MCG signals with CT using optical scanning

Magnetocardiography (MCG) can be used to noninvasively measure the electrophysiological activity of myocardial cells. The high spatial resolution of magnetic source localization can precisely determine the location of cardiomyopathy, which is of great significance for the diagnosis and treatment of cardiovascular disease. To perform magnetic source localization, MCG data must be co-registered with anatomical images. We propose a co-registration method that can be applied to OPM-MCG systems. In this method, the sensor array and the trunk of the subject are scanned using structured light-scanning technology, and the scan results are registered with the reconstructed structure using computed tomography (CT). This can increase the number of effective cloud points acquired and reduce the interference from respiratory motion. The scanning bed of the OPM-MCG system was modified to be consistent with the CT device, ensuring that the state of the body remains consistent between the cardiac magnetometry measurements and CT scans.

Early Progression of Abdominal Aortic Aneurysm is Decelerated by Improved Endothelial Barrier Function via ALDH2-LIN28B-ELK3 Signaling

The involvement of endothelial barrier function in abdominal aortic aneurysm (AAA) and its upstream regulators remains unknown. Single-cell RNA sequencing shows that disrupted endothelial focal junction is an early (3 days) and persistent (28 days) event during Angiotensin II (Ang II)-induced AAA progression. Consistently, mRNA sequencing on human aortic dissection tissues confirmed downregulated expression of endothelial barrier-related genes. Aldehyde dehydrogenase 2 (ALDH2), a negative regulator of AAA, is found to be upregulated in the intimal media of AAA samples, leading to testing its role in early-stage AAA. ALDH2 knockdown/knockout specifically in endothelial cells (ECs) significantly increases expression of EC barrier markers related to focal adhesion and tight junction, restores endothelial barrier integrity, and suppresses early aortic dilation of AAA (7 and 14 days post-Ang II). Mechanically, ELK3 acts as an ALDH2 downstream regulator for endothelial barrier function preservation. At the molecular level, ALDH2 directly binds to LIN28B, a regulator of ELK3 mRNA stability, hindering LIN28B binding to ELK3 mRNA, thereby depressing ELK3 expression and impairing endothelial barrier function. Therefore, preserving vascular endothelial barrier integrity via ALDH2-specific knockdown in ECs holds therapeutic potential in the early management of AAAs.

Deubiquitinase OTUD5 as a Novel Protector against 4-HNE-Triggered Ferroptosis in Myocardial Ischemia/Reperfusion Injury

Despite the development of advanced technologies for interventional coronary reperfusion after myocardial infarction, a substantial number of patients experience high mortality due to myocardial ischemia-reperfusion (MI/R) injury. An in-depth understanding of the mechanisms underlying MI/R injury can provide crucial strategies for mitigating myocardial damage and improving patient survival. Here, it is discovered that the 4-hydroxy-2-nonenal (4-HNE) accumulates during MI/R, accompanied by high rates of myocardial ferroptosis. The loss-of-function of aldehyde dehydrogenase 2 (ALDH2), which dissipates 4-HNE, aggravates myocardial ferroptosis, whereas the activation of ALDH2 mitigates ferroptosis. Mechanistically, 4-HNE targets glutathione peroxidase 4 (GPX4) for K48-linked polyubiquitin-related degradation, which 4-HNE-GPX4 axis commits to myocyte ferroptosis and forms a positive feedback circuit. 4-HNE blocks the interaction between GPX4 and ovarian tumor (OTU) deubiquitinase 5 (OTUD5) by directly carbonylating their cysteine residues at C93 of GPX4 and C247 of OTUD5, identifying OTUD5 as the novel deubiquitinase for GPX4. Consequently, the elevation of OTUD5 deubiquitinates and stabilizes GPX4 to reverse 4-HNE-induced ferroptosis and alleviate MI/R injury. The data unravel the mechanism of 4-HNE in GPX4-dependent ferroptosis and identify OTUD5 as a novel therapeutic target for the treatment of MI/R injury.

GDF-15 at admission predicts cardiovascular death, heart failure, and bleeding outcomes in patients with CAD

AIMS

We aimed to investigate the independent associations between growth differentiation factor 15 (GDF-15) level at admission and cardiovascular (CV) death, thrombotic events, heart failure (HF), and bleeding outcomes in patients with coronary artery disease (CAD).

METHODS AND RESULTS

We measured the plasma concentrations of GDF-15 centrally in patients from the BIomarker-based Prognostic Assessment for patients with Stable angina and acute coronary Syndrome (BIPass) registry, which consecutively enrolled patients with CAD from November 2017 to September 2019 at five tertiary hospitals in China. The outcomes included CV death, thrombotic events [myocardial infarction (MI) and ischaemic stroke], HF events [acute HF during hospitalization and hospitalization for HF post-discharge (A/H HF) and cardiogenic shock], and bleeding outcomes [non-coronary artery bypass grafting-related major bleeding and clinically significant bleeding (CSB)] during the 12 month follow-up period after hospitalization. Among 6322 patients with CAD {65.4% male, median age 63.7 [inter-quartile range (IQR)] 56.0-70.1 years}, the median concentration of plasma GDF-15 at admission was 1091 (IQR 790.5-1635.0) ng/L. Higher concentrations of GDF-15 were associated with an increased risk of CV death [hazard ratio (HR) 1.98, 95% confidence interval (CI) 1.35-2.88, P < 0.001], A/H HF (HR 2.69, 95% CI 1.92-3.77, P < 0.001), cardiogenic shock (HR 1.46, 95% CI 1.04-2.05, P = 0.029), and CSB (HR 1.48, 95% CI 1.22-1.79, P < 0.001), but not for MI or stroke, after adjusting for clinical risk factors and prognostic biomarkers. Adding GDF-15 to the model with risk factors and biomarkers improved the net reclassification for CV death, A/H HF, cardiogenic shock, and CSB.

CONCLUSIONS

In patients with CAD, admission levels of GDF-15 were associated with an increased 1 year risk of CV death, HF, and bleeding outcomes, but not with thrombotic events. GDF-15 may be a prognostic biomarker for CV death, HF, and bleeding outcomes and could be used to refine the risk assessment of these specific clinical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04044066.

Effects of Chest Compression on Ventilation Quality during Cardiopulmonary Resuscitation

Ventilation is an important part of cardiopulmonary resuscitation (CPR). The advanced airway mode and 30:2 mode are used for intubated and non-intubated patients, respectively. It is debatable that passive produced by 30 compressions can provide adequate tidal volume for 30:2 mode. In addition, the fragmented ventilation caused by continuous compression may result in ineffective ventilation. In the study, one pig was anaesthetized and intubated for 2 CPRs. Continuous chest compressions with ventilation and continuous chest compressions without mechanical ventilation were performed in 2 CPRs, respectively. Three 10-minute data segments including a period of normal ventilation (V segment), a period of only compressions without ventilation (C segment), and a period of compressions with ventilation (C-V segment) were used to analyze peek flow (PF), peek pressure (PP) and tidal volume. All the data was presented as mean ± standard deviation. Chest compression resulted in 14.90% increase in mean PP (2401.40 ± 94.75 Pa vs 2822.06 ± 291.10 Pa, p<0.05), 81.46% increase in average PF (319.58 ± 56.93 ml/s vs 579.92 ± 80.27 ml/s, p<0.05). The mean tidal volumes for C segment, V segment and C-V segment were 189.13 ml, 514.72 ml, and 429.26ml, respectively. Continuous compressions reduced the accumulative tidal volume, but when five compressions were made in one inspiratory phase, there is almost no loss of tidal volume (510.86 ± 47.24 ml vs 514.72 ± 29.25 ml, p<0.05). The study suggested the ventilator without feedback regulation might reduce the peek pressure during CPR and 5 compressions in 2 s inspiratory phase provided higher tidal volume.Clinical Relevance- This study shows that 150 chest compressions per minute provided greater tidal volume than 100 and 120 compressions per minute; continuous chest compressions could also provide a certain amount of oxygen supply.

ALDH2 attenuates myocardial pyroptosis through breaking down Mitochondrion-NLRP3 inflammasome pathway in septic shock

Cell survival or death is critical for cardiac function. Myocardial pyroptosis, as a newly recognized programmed cell death, remains poorly understood in sepsis. In this study, we evaluated the effect of aldehyde dehydrogenase (ALDH2) on myocardial pyroptosis and revealed the underlying mechanisms in sepsis. We established a septic shock mice model by intraperitoneal injection of Lipopolysaccharide (LPS, 15 mg/kg) 12 h before sacrifice. It was found that aldehyde dehydrogenase significantly inhibited NOD-like receptor protein 3 (NLRP3) inflammasome activation and Caspase-1/GSDMD-dependent pyroptosis, which remarkably improved survival rate and septic shock-induced cardiac dysfunction, relative to the control group. While aldehyde dehydrogenase knockout or knockdown significantly aggravated these phenomena. Intriguingly, we found that aldehyde dehydrogenase inhibited LPS-induced deacetylation of Hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex α subunit (HADHA) by suppressing the translocation of Histone deacetylase 3 (HDAC3) from nuclei to mitochondria. Acetylated HADHA is essential for mitochondrial fatty acid β-oxidation, and its interruption can result in accumulation of toxic lipids, induce mROS and cause mtDNA and ox-mtDNA release. Our results confirmed the role of Histone deacetylase 3 and HADHA in NOD-like receptor protein 3 inflammasome activation. Hdac3 knockdown remarkedly suppressed NOD-like receptor protein 3 inflammasome and pyroptosis, but Hadha knockdown eliminated the effect. aldehyde dehydrogenase inhibited the translocation of Histone deacetylase 3, protected ac-HADHA from deacetylation, and significantly reduced the accumulation of toxic aldehyde, and inhibited mROS and ox-mtDNA, thereby avoided NOD-like receptor protein 3 inflammasome activation and pyroptosis. This study provided a novel mechanism of myocardial pyroptosis through mitochondrial Histone deacetylase 3/HADHA- NOD-like receptor protein 3 inflammasome pathway and demonstrated a significant role of aldehyde dehydrogenase as a therapeutic target for myocardial pyroptosis in sepsis.

[AZD9291 suppresses proliferation and migration of nasopharyngeal carcinoma cells by inhibiting the PI3K-AKT-mTOR pathway]

OBJECTIVE

To investigate the effects of AZD9291 on the proliferation and migration of nasopharyngeal carcinoma cells.

METHODS

Nasopharyngeal carcinoma HNE1 and CNE2Z cells were treated with AZD9291 at the doses of 0.5, 1, 2, 4, and 8 μmol/L and at the doses of 1, 2, 4, 8, and 16 μmol/L, respectively. Cell survival was measured using CCK8 assay, and proliferation inhibition of the cells after AZD9291 treatment was examined with colony-forming assay; the cell repair and migration abilities were determined using scratch assay and Transwell experiment. The expressions of EGFR-related signaling proteins and migration-related proteins were detected using Western blotting.

RESULTS

The results of CCK8 assay and colonyforming assay showed that AZD9291 significantly inhibited the viability and proliferation of both HNE1 and CNE2Z cells (P < 0.01). AZD9291 treatment also attenuated the migration ability of HNE1 and CNE2Z cells (P < 0.01). Western blotting showed that, as the concentration of AZD9291 increased, the expression levels of the proteins involved in the PI3K-AKT-mTOR signaling pathway were lowered progressively (P < 0.01), resulting in inhibition of migration of HNE1 and CNE2Z cells (P < 0.01).

CONCLUSION

AZD9291 suppresses proliferation and attenuates repair and migration capacities of nasopharyngeal carcinoma cells by inhibiting the EGFR/PI3K/AKT/mTOR signaling pathway, suggesting the potential value of AZD9291 in the treatment of nasopharyngeal carcinoma.

Biomarker-based risk model to predict cardiovascular events in patients with acute coronary syndromes - Results from BIPass registry

BACKGROUND

Risk models integrating new biomarkers to predict cardiovascular events in acute coronary syndromes (ACS) are lacking. Therefore, we evaluated the prognostic value of biomarkers in addition to clinical predictors and developed a biomarker-based risk model for major adverse cardiovascular events (MACE) within 12 months after hospital admission with ACS.

METHODS

Patients (n = 4407) consecutively enrolled from November, 2017 to October, 2019 in three hospitals of a prospective Chinese registry (BIomarker-based Prognostic Assessment for Patients with Stable Angina and Acute Coronary Syndromes, BIPass) were designated as the risk model development cohort. Validation was performed in 1409 patients enrolled in two independent hospitals. Cox proportional hazards regression analysis was used to generate a risk prediction model and evaluate the incremental prognostic value of each biomarker.

FINDINGS

Over 12 months, 196 patients experienced MACE (5.1%/year). Among twelve candidate biomarkers, N-terminal pro-B-type natriuretic peptide (NT-proBNP) measured at baseline showed the most prognostic capability independent of clinical predictors. The developed BIPass risk model included age, hypertension, previous myocardial infarction, stroke, Killip class, heart rate, and NT-proBNP. It displayed improved discrimination (C-statistic 0.79, 95% CI 0.73-0.85), calibration (GOF = 9.82, p = 0.28) and clinical decision curve in the validation cohort, outperforming the GRACE and TIMI risk scores. Cumulative rates for MACE demonstrated good separation in the BIPass predicted low, intermediate, and high-risk groups.

INTERPRETATION

The BIPass risk model, integrating clinical variables and NT-proBNP, is useful for predicting 12-month MACE in ACS. It effectively identifies a gradient risk of cardiovascular events to aid personalized care.

FUNDING

National Key R&D Program of China (2017YFC0908700, 2020YFC0846600), National S&T Fundamental Resources Investigation Project (2018FY100600, 2018FY100602), Taishan Pandeng Scholar Program of Shandong Province (tspd20181220), Taishan Young Scholar Program of Shandong Province (tsqn20161065, tsqn201812129), Youth Top-Talent Project of National Ten Thousand Talents Plan and Qilu Young Scholar Program.

Macrophage ALDH2 (Aldehyde Dehydrogenase 2) Stabilizing Rac2 Is Required for Efferocytosis Internalization and Reduction of Atherosclerosis Development

BACKGROUND

Clinical studies show that the most common single-point mutation in humans, ALDH2 (aldehyde dehydrogenase 2) rs671 mutation, is a risk factor for the development and poor prognosis of atherosclerotic cardiovascular diseases, but the underlying mechanism remains unclear. Apoptotic cells are phagocytosed and eliminated by macrophage efferocytosis during atherosclerosis, and enhancement of arterial macrophage efferocytosis reduces atherosclerosis development.

METHODS

Plaque areas, necrotic core size, apoptosis, and efferocytosis in aortic lesions were investigated in APOE-/- mice with bone marrow transplanted from APOE-/-ALDH2-/- and APOE-/- mice. RNA-seq, proteomics, and immunoprecipitation experiments were used to screen and validate signaling pathways affected by ALDH2. Efferocytosis and protein levels were verified in human macrophages from wild-type and rs671 mutation populations.

RESULTS

We found that transplanting bone marrow from APOE-/-ALDH2-/- to APOE-/- mice significantly increased atherosclerosis plaques compared with transplanting bone marrow from APOE-/- to APOE-/- mice. In addition to defective efferocytosis in plaques of APOE-/- mice bone marrow transplanted from APOE-/-ALDH2-/- mice in vivo, macrophages from ALDH2-/- mice also showed significantly impaired efferocytotic activity in vitro. Subsequent RNA-seq, proteomics, and immunoprecipitation experiments showed that wild-type ALDH2 directly interacted with Rac2 and attenuated its degradation due to decreasing the K48-linked polyubiquitination of lysine 123 in Rac2, whereas the rs671 mutant markedly destabilized Rac2. Furthermore, Rac2 played a more crucial role than other Rho GTPases in the internalization process in which Rac2 was up-regulated, activated, and clustered into dots. Overexpression of wild-type ALDH2 in ALDH2-/- macrophages, rather than the rs671 mutant, rescued Rac2 degradation and defective efferocytosis. More importantly, ALDH2 rs671 in human macrophages dampened the apoptotic cells induced upregulation of Rac2 and subsequent efferocytosis.

CONCLUSIONS

Our study has uncovered a pivotal role of the ALDH2-Rac2 axis in mediating efferocytosis during atherosclerosis, highlighting a potential therapeutic strategy in cardiovascular diseases, especially for ALDH2 rs671 mutation carriers.

Tumor microenvironment and its clinicopathological and prognostic associations in surgically resected cutaneous angiosarcoma

PURPOSE

Cutaneous angiosarcoma (CAS) is a rare but typically aggressive malignant vascular neoplasm of the skin. Tumor microenvironment (TME) of CAS and its associations with baseline clinicopathological features and patient outcomes are very important, especially when considering the recent advances in understanding of the tumor biology.

METHODS/PATIENTS

We retrospectively reviewed medical records of patients who underwent surgical resection for CAS at a tertiary Hospital. The pretreated specimens were evaluated by immunohistochemistry for programmed cell death protein 1 (PD-1) and its ligand (PD-L1), densities of tumor infiltrative lymphocytes (TILs) (CD3+, CD4+, CD8+, CD45RO+, FoxP3+), as well as c-MYC and Ki-67 expressions. Overall survival (OS) was estimated by Kaplan-Meier method and compared with Log-rank test.

RESULTS

A total of 21 CAS patients were identified. Median age was 67 (ranges: 20-81) years, 14 (66.7%) were male, and over 50% had lesions of scalp. Histopathological examination showed a predominantly spindle cell type (57.1%). All patients underwent surgery, 16 (76.2%) were treated further. PD-L1 was positively stained (> 1%) in tumor cells (42.9%) and TILs (23.8%). PD-1 expression (> 1%) was identified in TILs of 11 (52.4%) cases. PD-1/PD-L1 expressions were significantly associated with the higher densities of CD3+, CD4+, CD8+, CD45RO+, and Foxp3+ TILs, but not with patient characteristics or c-MYC or Ki-67 expression. Median OS was 18.5 months (95% CI 6.0-35.9), although no prognostic significance was observed with respect to any clinicopathological features.

CONCLUSION

We characterized TME and its clinical and prognostic association in CAS. PD-1/PD-L1 expressions were significantly associated with TILs subtypes but not with OS.

Global magnitude of encephalitis burden and its evolving pattern over the past 30 years

OBJECTIVE

We aimed to estimate the spatiotemporal patterns of the encephalitis burden along with its attributable risk factors at the national, regional, and global levels, which may be helpful in guiding targeted prevention and treatment programs.

METHODS

Based on available data sources, the incidence, mortality, and disability-adjusted life years (DALYs) of encephalitis in 204 countries and regions from 1990 to 2019 were reconstructed by the Global Burden of Disease Study 2019 using the Cause of Death Ensemble model, spatiotemporal Gaussian process regression, and DisMod-MR 2.1. We conducted a systematic analysis on the epidemiological characteristics of encephalitis in detail by gender, region, and age over the past three decades.

RESULTS

Globally, 1,444,720 incident cases, 89,900 deaths, and 4.80 million DALYs related to encephalitis were estimated in 2019. The age-standardized incidence rate and age-standardized mortality rate (ASMR) decreased from 23.17 and 2.18 to 19.33 and 1.19 per 100,000 person-years over the past 30 years, respectively. However, beginning in 2011-2013, the burden of encephalitis has shown an inflection point, with a further decline of the ASRs ceasing. Lower socio-demographic index (SDI) regions in South Asia, Western and Eastern Sub-Saharan Africa had the highest burden of encephalitis in 2019. During the past three decades, most countries of South Asia achieved significant control of the burden. In contrast, developed countries with a higher SDI have shown a notable increase in ASMR and age-standardized DALYs rate. Children and older adults have always been high-risk groups for encephalitis.

CONCLUSION

Although the global burden of encephalitis has decreased in the past 30 years, a further decline stopped from 2011-2013. The diverse burden in different regions calls for differentiated management, and the persistent high burden in some low-SDI regions and the increased burden in developed countries with higher SDIs deserve more attention.

ABBREVIATIONS

ASDR: age-standardized DALY rate, ASIR: age-standardized incidence rate, ASMR: age-standardized mortality rate, ASR: age-standardized rate, CI: confidence interval, DALY: disability-adjusted life-year, EAPC: estimated annual percentage change, GBD: Global Burden of Disease Study, HAP: household air pollution from solid fuels, HSE: herpes simplex encephalitis, HSV: herpes simplex virus, ICD: International Classification of Diseases, JE: Japanese encephalitis, PCR: polymerase chain reaction, SDI: socio-demographic index, TBE: tick-borne encephalitis, UI: uncertainty interval.

Malnutrition Contributes to Low Lymphocyte Count in Early-Stage Coronavirus Disease-2019

Background and Aim: Lymphocytes play an important role in fighting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Low total lymphocyte count (TLC), which contributes to poor clinical outcomes, is common in persons with coronavirus disease 2019 (COVID-19). The current explanation for the cause of low TLC is that it is directly related to the invasiveness of SARS-CoV-2, which attacks lymphocytes. We hypothesized that malnutrition contributes to the development of low TLC in early-stage COVID-19. Methods: We prospectively enrolled 101 patients with confirmed COVID-19. On their first day of hospitalization, we collected baseline and laboratory data, including clinical symptoms; the Sequential Organ Failure Assessment, Nutrition Risk Screening 2002 and Subjective Global Assessment were used to assess the malnutrition status of the patients. Multivariable logistic regression was used to identify independent risk factors for low TLC and severe COVID-19. Results: Malnutrition was associated with lower TLC in COVID-19. Fifty-nine (58.4%) of the patients showed low TLC, 41 (40.6%) were at risk for malnutrition, and 18 of them were malnourished. Low TLC was an independent risk factor for severe COVID-19. Compared to patients with normal TLC, those with low TLC more often presented with anorexia, malnutrition, higher SOFA scores (P < 0.05) and comorbidities (diabetes and malignancies). Malnutrition (OR: 3.05, 95% CI: 1.5-6.19, P = 0.006) and SOFA scores (OR: 1.51, 95% CI: 1.04-2.43, P = 0.042) were identified as independent risk factors for low TLC. Conclusions: Malnutrition was common among our patients with early-stage COVID-19, and it contributed to the occurrence of low TLC.

Population genomic screening of all young adults in Australia to detect familial hypercholesterolemia: a cost-effectiveness analysis

Background

Heterozygous familial hypercholesterolemia (FH) is a highly-penetrant, autosomal dominant monogenic disorder that causes elevated plasma low-density cholesterol (LDL-C) levels and risk of premature coronary heart disease (CHD). To date, the cost-effectiveness of the emerging strategy of genomic screening of adult populations for FH has not been investigated.

Purpose

To assess the impact and cost-effectiveness of offering population genomic screening to all young adults in Australia to detect heterozygous familial hypercholesterolemia (FH).

Methods

We designed a decision analysis model to compare the current standard of care for heterozygous FH diagnosis in Australia (opportunistic cholesterol screening and genetic cascade testing) with population genomic screening of adults aged 18–40 years to detect pathogenic variants in the LDLR/APOB/PCSK9 genes. The model captured morbidity/mortality due to coronary heart disease (CHD) over a lifetime horizon, from a healthcare perspective. Risk of CHD, treatment effects, prevalence, and healthcare costs were estimated from published studies. Outcomes included quality adjusted life years (QALYs), costs and incremental cost-effectiveness ratio (ICER), discounted 5% annually. Sensitivity analyses were undertaken to explore the impact of key input parameters on the robustness of the model. The model structure was designed to be transferable to countries with different healthcare systems.

Results

Over the lifetime of the population (4,167,768 men; 4,129,961 women), the model estimated a gain of 62,722 years of life lived and 73,959 QALYs due to CHD prevention. Population genomic screening for FH would be cost-effective from a healthcare perspective if the cost per test was ≤AU$300 (∼US$233) which would yield an ICER AU$28,000 cost-saving.

Conclusion

Based on our model, offering population genomic screening to all young adults to detect FH could be cost-effective in the Australian healthcare system, at testing costs that are currently feasible.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This work was supported by the Australian National Heart Foundation and Monash University Faculty of Medicine, Nursing and Health Sciences Results from scenario analysesResults from Monte Carlo simulations

PCSK9 inhibition with alirocumab decreases plasma lipoprotein(a) concentration by a dual kinetic mechanism of action

Background

Lipoprotein(a) [Lp(a)] is a low-density lipoprotein (LDL)-like particle, covalently bound to apolipoprotein(a) [apo(a)]. Recent trials show that proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, such as alirocumab, decrease plasma Lp(a) levels and risk of atherosclerotic cardiovascular disease (ASCVD). The kinetic mechanism for lowering Lp(a) by PCSK9 inhibitors may differ according to pre-treatment apo(a) levels.

Purpose

We investigated the effect of alirocumab on Lp(a) metabolism in 21 long-term statin-treated patients [Lp(a) &gt;0.5 g/L in all] with moderate-high (n=10) and high (n=11) apo(a) concentrations according to a cutoff of median apo(a) levels of 145 nmol/L.

Methods

Apo(a) kinetics were studied before and after 12-week treatment with alirocumab (150 mg subcutaneously fortnightly). Apo(a) fractional catabolic rate (FCR) and production rate (PR) were determined using intravenous D3-leucine administration, mass spectrometry and compartmental modelling.

Results

The plasma concentration and PR of apo(a) were significantly higher in patients with high apo(a) than in patients with moderate-high apo(a) levels (273±30 nmol/L vs 130±4.7 nmol/L and 6.0±0.69 nmol/kg/day vs 2.6±0.15 nmol/kg/day, respectively; P&lt;0.001). The FCR of apo(a) was not significantly different between two groups (0.48±0.02 pools/day vs 0.45±0.01 pools/day, P&gt;0.05). In patients with moderate-high apo(a) levels, alirocumab significantly lowered plasma apo(a) levels (−17%, P&lt;0.01) and increased the FCR of apo(a) (+26%, P&lt;0.001), but did not alter apo(a) PR. In contrast, alirocumab significantly lowered plasma apo(a) concentrations (−31%, P&lt;0.001) via a dual mechanism that increased apo(a) FCR (+31%, P&lt;0.001) and lowered PR (−9%, P&lt;0.05) in patients with high apo(a) levels. The reductions in apo(a) concentration and PR with alirocumab in the high apo(a) group remained significant after adjusting for background statin when compared with patients with moderate-high apo(a) levels (P&lt;0.05).

Conclusions

In statin-treated patients with elevated Lp(a), alirocumab may lower elevated plasma Lp(a) concentrations by a dual mechanism of increasing the catabolism and decreasing the production of Lp(a) particles, specifically in patients with relatively high apo(a) concentrations.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This independent research was funded by an Investigator Initiated Study Concept Research Grant from Regeneron Pharmaceuticals and Sanofi (Protocol No. LPS 14508). Figure 1Figure 2

[Chuanxiong Rhizoma inhibits brain metastasis of lung cancer through multiple active ingredients acting on multiple targets, pathways and biological functions]

OBJECTIVE

To explore the molecular mechanism mediating the inhibitory effect of Chuanxiong Rhizoma against brain metastasis of lung cancer using network pharmacology methods and molecular docking.

METHODS

The chemical components of Chuanxiong Rhizoma and their targets were obtained through the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. The relevant targets for brain metastasis of lung cancer were screened using the GeneCards database. Clusterpro-filerR package was used to perform GO and KEGG enrichment analysis. Cytoscape and STRING database were used to construct the "active ingredient-target-disease" network and protein-protein interaction (PPI) network of Chuanxiong Rhizoma. The core components of Chuanxiong Rhizoma and their targets in the treatment of lung cancer brain metastasis were screened based on the topological parameters, and the results were verified using molecular docking and in Chuanxiong extract- treated human lung cancer PC9 cells by detecting the core target with Western blotting.

RESULTS

Forty-eight active ingredients of Chuanxiong Rhizoma including (Z)-ligustilide, butylphthalide, oleic acid, and myricetone were screened, which target 49 proteins including INS, BDNF, FOS, VEGFA, PTGS2, ESR1, MAPK14, and PTGS1. These proteins participated in 57 biological functions such as nuclear receptor activity, ligand activation, and transcription factor activity, involving 40 signaling pathways such as prolactin signaling pathway, breast cancer, and etrogen signaling. The results of molecular docking showed that myricetone, butylphthalide, 4-hydroxy-3 butylphthalide, (Z)-ligustilide, and ligustalide-E, among others, had strong affinities to 7 cores targets including BDNF, FOS, PTGS2, and MAPK14. In PC9 cells, treatment with Chuanxiong Rhizoma extract resulted in significant reductions in the phosphorylation levels of PI3K, Akt and VEGF (P < 0.01).

CONCLUSION

Chuanxiong Rhizoma contains multiple active ingredients against brain metastasis lung cancer, and these ingredients act on multiple targets involving multiple signal pathways and biological functions.

Ten-Year Changes in Bloodstream Infection With Acinetobacter Baumannii Complex in Intensive Care Units in Eastern China: A Retrospective Cohort Study

Background: There is little evidence on the changing prevalence, microbiological profile, and outcome of nosocomial Acinetobacter baumannii complex (ABC)-caused bloodstream infection (ABCBSI) specified in intensive care units (ICUs) in long-term studies, especially in China. Objective: We aimed to investigate changes in incidence, antibiotic resistance, therapy, and prognosis of ABCBSI in ICUs in eastern China during 2009-2018. Methods: A multicenter retrospective cohort study was conducted, and microbiological and clinical data for patients with ABCBSI acquired in nine adult ICUs in eastern China from 2009 to 2018. Results: A total of 202 cases were enrolled. For the years 2009-2010, 2011-2012, 2013-2014, 2015-2016, and 2017-2018, the incidence of ABCBSI increased significantly, as did the percentage of pan-drug-resistant isolates and resistant rates to most of antimicrobial agents; the percentage of drug-sensitive isolates decreased (all P < 0.05). The frequency of treatment with carbapenems and tigecycline increased, and that of cephalosporins decreased. Compared with those in the first years (2009-2012), ABCBSI patients in the lattermost years (2017-2018) were less often treated with appropriate empirical therapy, more often underwent pneumonia-related ABCBSI and mechanical ventilation support, and had higher 28-day mortality rates. Multivariate Cox regression indicated that increase in the degree of ABC antibiotics resistance, pneumonia-related ABCBSI, and septic shock were risk factors of 28-day mortality and associated with significant lower survival days. Conclusions: The past decade has witnessed a marked increase in the incidence of ABCBSI and in antibiotic resistance, with increasing pneumonia-related infections and worrisome mortality in ICUs in China. Controlling increasing resistance and preventing nosocomial pneumonia may play important roles in combatting these infections.

Aldehyde dehydrogenase 2 protects against acute kidney injury by regulating autophagy via the Beclin-1 pathway

The mitochondrial enzyme aldehyde dehydrogenase 2 (ALDH2) catalyzes the detoxification of acetaldehyde and endogenous lipid aldehydes. Approximately 40% of East Asians, accounting for 8% of the human population, carry the E504K mutation in ALDH2 that leads to accumulation of toxic reactive aldehydes and increases the risk for cardiovascular disease, cancer, and Alzheimer disease, among others. However, the role of ALDH2 in acute kidney injury (AKI) remains poorly defined and is therefore the subject of the present study using various cellular and organismal sources. In murine models, in which AKI was induced by either the contrast agent iohexol or renal ischemia/reperfusion, KO, activation/overexpression of ALDH2 were associated with increased and decreased renal injury, respectively. In murine renal tubular epithelial cells (RTECs), ALDH2 upregulated Beclin-1 expression, promoted autophagy activation, and eliminated ROS. In vivo and in vitro, both 3-MA and Beclin-1 siRNAs inhibited autophagy and abolished ALDH2-mediated renoprotection. In mice with iohexol-induced AKI, ALDH2 knockdown in RTECs using AAV-shRNA impaired autophagy activation and aggravated renal injury. In human renal proximal tubular epithelial HK-2 cells exposed to iohexol, ALDH2 activation potentiated autophagy and attenuated apoptosis. In mice with AKI induced by renal ischemia/reperfusion, ALDH2 overexpression or pretreatment regulated autophagy mitigating apoptosis of RTECs and renal injury. In summary, our data collectively substantiate a critical role of ALDH2 in AKI via autophagy activation involving the Beclin-1 pathway.

EGFR tyrosine kinase inhibitor Almonertinib induces apoptosis and autophagy mediated by reactive oxygen species in non-small cell lung cancer cells

Almonertinib, a new third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is highly selective to EGFR T790M-mutant non-small cell lung cancer (NSCLC). However, there is no available information on the form and molecular mechanism of Almonertinib-induced death in NSCLC cells. Herein, CCK-8 and colony formation assays, flow cytometry, electron microscopy, and western blots assay showed that Almonertinib inhibited NSCLC cells growth and proliferation by inducing apoptosis and autophagy which can be inhibited by a broad spectrum of caspase inhibitor Z-VAD-fmk or autophagy inhibitor chloroquine. Importantly, Almonertinib-induced autophagy was cytoprotective in NSCLC cells, and the blockade of autophagy improved cell apoptosis. In addition, Almonertinib increased reactive oxygen species (ROS) generation and clearance of ROS through pretreatment with N-acetyl-L-cysteine (NAC) inhibited the decrease of cell viability, apoptosis and increase of LC3-II induced by Almonertinib. The results of Western blot showed that both EGFR activity and downstream signaling pathways were inhibited by Almonertinib. Taken together, these findings indicated that Almonertinib induced apoptosis and autophagy by promoting ROS production in NSCLC cells.

[Development and functional validation of a nano-delivery system of miR-16/polypeptide targeting ovarian cancer cells]

OBJECTIVE

To develop a nano-delivery system for targeted delivery of miR-16/polypeptide for enhancing cisplatin sensitivity of ovarian cancer.

OBJECTIVE

R9-SS-R9 and cRGD-R9-SS-R9 peptides were synthesized and self-assembled with miR-16 molecules to form a nano-delivery system. The stability, particle size, potential and morphology of the nanoparticles were determined by agarose gel electrophoresis, particle size potentiometer and transmission electron microscopy. CCK-8 assay was used to assess the toxicity of the polypeptides in ovarian cancer cells. Stem loop qRT-PCR and living cell imaging were used to verify the uptake efficiency and intracellular distribution of the nanoparticles. Flow cytometry and Western blotting were performed to verify the effect of the nanoparticles for enhancing cisplatin sensitivity of ovarian cancer cells and explore the possible mechanism.

OBJECTIVE

R9-SS-R9/miR-16 and cRGD-R9-SS-R9/miR-16 nanoparticles were successfully prepared. The nanoparticles, with a particle size below 150 nm, a dispersity index less than 0.1 and a potential of about 40 mV, showed a good serum stability. The polypeptide material had no obvious cytotoxicity. The miR-16/polypeptide nanoparticles could be efficiently absorbed by human ovarian cancer cells and were distributed in the cytoplasm. The nanoparticles significantly increased the intracellular expression level of miR-16 (P < 0.001) and decreased the expression of Bcl-2 and Chk-1 proteins in ovarian cancer cells, thus enabling miR-16 to promote apoptosis and enhance cisplatin sensitivity of the cells.

OBJECTIVE

We successfully prepared a miR-16/polypeptide nano-delivery system for targeted delivery of miR-16 to ovarian cancer cells for enhancing cisplatin sensitivity of the cancer cells.

Prevention of aortic dissection and aneurysm via an ALDH2-mediated switch in vascular smooth muscle cell phenotype

AIMS

Aortic aneurysm/dissection (AAD) is a life-threatening disorder lacking effective pharmacotherapeutic remedies. Aldehyde dehydrogenase 2 (ALDH2) polymorphism is tied with various risk factors for AAD including hypertension, atherosclerosis, and hypercholesterolaemia although direct correlation between the two remains elusive.

METHODS AND RESULTS

Two independent case-control studies were conducted involving 307 AAD patients and 399 healthy controls in two geographically distinct areas in China. Our data revealed that subjects carrying mutant ALDH2 gene possessed a ∼50% reduced risk of AAD compared with wild-type (WT) alleles. Using 3-aminopropionitrile fumarate (BAPN)- and angiotensin II (Ang II)-induced AAD animal models, inhibition of ALDH2 was found to retard development of AAD. Mechanistically, ALDH2 inhibition ablated pathological vascular smooth muscle cell (VSMC) phenotypical switch through interaction with myocardin, a determinant of VSMC contractile phenotype. Using microarray and bioinformatics analyses, ALDH2 deficiency was found to down-regulate miR-31-5p, which further altered myocardin mRNA level. Gain-of-function and loss-of-function studies verified that miR-31-5p significantly repressed myocardin level and aggravated pathological VSMC phenotypical switch and AAD, an effect that was blunted by ALDH2 inhibition. We next noted that ALDH2 deficiency increased Max expression and decreased miR-31-5p level. Moreover, ALDH2 mutation or inhibition down-regulated levels of miR-31-5p while promoting myocardin downstream contractile genes in the face of Ang II in primary human VSMCs.

CONCLUSIONS

ALDH2 deficiency is associated with a lower risk of AAD in patients and mice, possibly via suppressing VSMC phenotypical switch in a miR-31-5p-myocardin-dependent manner. These findings favour a role for ALDH2 and miR-31-5p as novel targets for AAD therapy.

Cardiovascular and behavioural risk factors in families with elevated lipoprotein(a)[Lp(a)]

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Elevated lipoprotein(a)[Lp(a)] is an inherited and independent risk factor for atherosclerotic cardiovascular diseases (ASCVD). However, it is an under detected condition with no specific therapy available at present for lowering Lp(a). Hence, identifying the distribution of modifiable cardiovascular and behavioural risk factors is important for implementing an effective intervention programme to mitigate the overall risk of ASCVD in high-risk individuals with elevated Lp(a).

Purpose

The primary aim was to describe and compare the distribution of modifiable cardiovascular and behavioural risk factors in both index cases and their relatives with elevated Lp(a) identified through cascade testing at the Lipid Disorders Clinic, Royal Perth Hospital.

Methods

We studied 51 index cases and 71 relatives cascade tested with elevated Lp(a) (≥0.5 g/L).  Questionnaires were completed concerning aspects of cardiovascular health (cholesterol level, blood pressure and blood glucose level) and behavioural health metrics (diet, smoking, physical activity, body-mass-index [BMI]). Lp(a) was measured by an immunoassay having minimal dependence on apolipoprotein(a) isoform size. The health metrics were described as proportions and statistical analyses performed using Student’s t-test or Chi-square where appropriate.

Results

Compared with the index cases, a higher proportion of their affected relatives were female (62% vs 43%, p = 0.039), younger (43 years vs 53 years, p &lt; 0.001) and had lower Lp(a) levels (1.03 g/L vs 1.12 g/L, p = 0.003). A lower proportion of the affected relatives were treated for dyslipidaemia (31% vs 96%, p &lt; 0.001). The affected relatives also had a lower incidence of ASCVD events (3% vs 37%, p &lt; 0.001), hypertension (21% vs 43%, p = 0.003), and lower HbA1c levels (5.3% vs 5.9%, p = 0.031) compared with index cases. Additionally, a larger proportion of the affected relatives had ideal cardiovascular health (35% vs 14%, p = 0.008) compared with their index cases. However, more than half of the index cases and their relatives did not maintain a healthy diet (59% and 69%, respectively) and an ideal BMI (68% and 59%, respectively).

Conclusion(s)

Although the younger affected relatives with elevated Lp(a) have a lower cardiovascular risk compared with the index cases, a focus on modifiable behavioural changes, such as a healthy diet and an ideal body weight, is still required to mitigate the overall risk of ASCVD.

Colonization With Extensively Drug-Resistant Acinetobacter baumannii and Prognosis in Critically Ill Patients: An Observational Cohort Study

Background: Acinetobacter baumannii is one of the most frequently isolated opportunistic pathogens in intensive care units (ICUs). Extensively drug-resistant A. baumannii (XDR-AB) strains lack susceptibility to almost all antibiotics and pose a heavy burden on healthcare institutions. In this study, we evaluated the impact of XDR-AB colonization on both the short-term and long-term survival of critically ill patients. Methods: We prospectively enrolled patients from two adult ICUs in Qilu Hospital of Shandong University from March 2018 through December 2018. Using nasopharyngeal and perirectal swabs, we evaluated the presence of XDR-AB colonization. Participants were followed up for 6 months. The primary endpoints were 28-day and 6-month mortality after ICU admission. The overall survival rate was estimated by the Kaplan-Meier method. We identified risk factors associated with 28-day and 6-month mortality using the logistic regression model and a time-dependent Cox regression model, respectively. Results: Out of 431 patients, 77 were colonized with XDR-AB. Based on the Kaplan-Meier curve results, the overall survival before 28 days did not differ by colonization status; however, a significantly lower overall survival rate was obtained at 6 months in colonized patients. Univariate and multivariate analysis results confirmed that XDR-AB colonization was not associated with 28-day mortality, but was an independent risk factor of lower overall survival at 6 months (HR = 1.749, 95% CI = 1.174-2.608). Conclusions: XDR-AB colonization has no effect on short-term overall survival, but is associated with lower long-term overall survival in critically ill patients.

Efficacy and tolerability of bevacizumab in patients with severe Covid-19

On the basis of Covid-19-induced pulmonary pathological and vascular changes, we hypothesize that the anti-vascular endothelial growth factor (VEGF) drug bevacizumab might be beneficial for treating Covid-19 patients. From Feb 15 to April 5, 2020, we conducted a single-arm trial (NCT04275414) and recruited 26 patients from 2-centers (China and Italy) with severe Covid-19, with respiratory rate ≥30 times/min, oxygen saturation ≤93% with ambient air, or partial arterial oxygen pressure to fraction of inspiration O₂ ratio (PaO₂/FiO₂) >100 mmHg and ≤300 mmHg, and diffuse pneumonia confirmed by chest imaging. Followed up for 28 days. Among these, bevacizumab plus standard care markedly improves the PaO₂/FiO₂ ratios at days 1 and 7. By day 28, 24 (92%) patients show improvement in oxygen-support status, 17 (65%) patients are discharged, and none show worsen oxygen-support status nor die. Significant reduction of lesion areas/ratios are shown in chest computed tomography (CT) or X-ray within 7 days. Of 14 patients with fever, body temperature normalizes within 72 h in 13 (93%) patients. Relative to comparable controls, bevacizumab shows clinical efficacy by improving oxygenation and shortening oxygen-support duration. Our findings suggest bevacizumab plus standard care is highly beneficial for patients with severe Covid-19. Randomized controlled trial is warranted.

In this single-arm clinical trial, the authors show that treatment of COVID-19 patients with bevacizumab, an anti-vascular endothelial growth factor drug, can improve PaO₂/FiO₂ ratios and oxygen-support status. Relative to an external control group, bevacizumab shows clinical efficacy by improving oxygenation.

Fundamental Mechanisms of the Cell Death Caused by Nitrosative Stress

Nitrosative stress, as an important oxygen metabolism disorder, has been shown to be closely associated with cardiovascular diseases, such as myocardial ischemia/reperfusion injury, aortic aneurysm, heart failure, hypertension, and atherosclerosis. Nitrosative stress refers to the joint biochemical reactions of nitric oxide (NO) and superoxide (O₂ ^-) when an oxygen metabolism disorder occurs in the body. The peroxynitrite anion (ONOO^-) produced during this process can nitrate several biomolecules, such as proteins, lipids, and DNA, to generate 3-nitrotyrosine (3-NT), which further induces cell death. Among these, protein tyrosine nitration and polyunsaturated fatty acid nitration are the most studied types to date. Accordingly, an in-depth study of the relationship between nitrosative stress and cell death has important practical significance for revealing the pathogenesis and strategies for prevention and treatment of various diseases, particularly cardiovascular diseases. Here, we review the latest research progress on the mechanisms of nitrosative stress-mediated cell death, primarily involving several regulated cell death processes, including apoptosis, autophagy, ferroptosis, pyroptosis, NETosis, and parthanatos, highlighting nitrosative stress as a unique mechanism in cardiovascular diseases.

Current Evidence of Interleukin-6 Signaling Inhibitors in Patients With COVID-19: A Systematic Review and Meta-Analysis

Background: Interleukin-6 (IL-6) is known to be detrimental in coronavirus disease 2019 (COVID-19) because of its involvement in driving cytokine storm. This systematic review and meta-analysis aimed to assess the safety and efficacy of anti-IL-6 signaling (anti-IL6/IL-6R/JAK) agents on COVID-19 based on the current evidence. Methods: Studies were identified through systematic searches of PubMed, EMBASE, ISI Web of Science, Cochrane library, ongoing clinical trial registries (clinicaltrials.gov), and preprint servers (medRxiv, ChinaXiv) on August 10, 2020, as well as eligibility checks according to predefined selection criteria. Statistical analysis was performed using Review Manager (version 5.3) and STATA 12.0. Results: Thirty-one studies were included in the pooled analysis of mortality, and 12 studies were identified for the analysis of risk of secondary infections. For mortality analysis, 5630 COVID-19 cases including 2,132 treated patients and 3,498 controls were analyzed. Anti-IL-6 signaling agents plus standard of care (SOC) significantly decreased the mortality rate compared to SOC alone (pooled OR = 0.61, 95% CI 0.45-0.84, p = 0.002). For the analysis of secondary infection risk, 1,624 patients with COVID-19 including 639 treated patients and 985 controls were included, showing that anti-IL-6 signaling agents did not increase the rate of secondary infections (pooled OR = 1.21, 95% CI 0.70-2.08, p = 0.50). By contrast, for patients with critical COVID-19 disease, anti-IL-6 signaling agents failed to reduce mortality compared to SOC alone (pooled OR = 0.75, 95% CI 0.42-1.33, p = 0.33), but they tended to increase the risk of secondary infections (pooled OR = 1.85, 95% CI 0.95-3.61, p = 0.07). A blockade of IL-6 signaling failed to reduce the mechanical ventilation rate, ICU admission rate, or elevate the clinical improvement rate. Conclusion: IL-6 signaling inhibitors reduced the mortality rate without increasing secondary infections in patients with COVID-19 based on current studies. For patients with critical disease, IL-6 signaling inhibitors did not exhibit any benefit.

Health economic evaluation of screening and treating children with familial hypercholesterolemia early in life: many happy returns on investment?

Background

There are no studies that have specifically investigated the cost-effectiveness of cascade screening of children for heterozygous familial hypercholesterolemia (FH) and treatment of affected individuals with statins to prevent coronary heart disease (CHD).

Purpose

This study explores the cost-effectiveness of this strategy from the perspective of the Australian public healthcare system.

Methods

A lifetime Markov model with four health states (Alive without CHD, Alive with CHD, Dead from fatal CHD, and Dead from other causes) was developed to simulate the progression of ten- year-old children screened for FH and treated immediately with statins if found to have FH. The underlying prevalence of FH in this target population was assumed to be 56.8%, and the sensitivity and specificity of testing was 100%. The comparator was usual care, which assumed that subjects started statins spontaneously at a later point or when they experienced a cardiovascular event. The effect of reducing low-density lipoprotein cholesterol (LDL-C) on the risk of a first event at each age assumed that risk was proportional to total lifetime exposure and was implemented using Mendelian randomisation analysis data. Cost and other outcome data were sourced from published sources. Outcome of interests were costs in Australian dollars (AUD), life years gained (LYG) and quality-adjusted life years (QALYs) gained, as well as incremental cost-effectiveness ratios (ICERs) of costs per LYG and per QALY gained. All future costs and outcomes were discounted by 5% annually.

Results

Undiscounted results showed that compared with usual care, cascade screening of ten year-old children for FH and initiation of treatment of affected individuals saved 7.77 LYG and 7.53 QALYs per person over a lifetime. With 5% annual discounting, there were 0.97 LYG and 1.07 QALYs gained per person, at an additional cost of $3,244. These equated to ICERs of $3334 per LYG and $3023 per QALY gained. The equivalent ICERs in USD would be $5089 per LYG gained and $4615 per QALY gained. Sensitivity analysis showed the results to be robust.

Conclusions

Compared to usual care, cascade screening of ten year old children for FH and treating affected individuals is likely to be highly cost-effective.

Table 1. Granular cost and benefit data

Funding Acknowledgement

Type of funding source: None

PHACTR1, a pro-atherosclerotic mechanosensitive PPARgamma corepressor in endothelial cells

Background

Numerous genome-wide association studies revealed that SNPs at phosphatase and actin regulator 1 (PHACTR1) locus are strongly correlated with coronary artery disease (CAD). However, the mechanism linking these variants to CAD remains uncertain.

Purpose

We studied the biological functions and molecular mechanisms of PHACTR1 in atherosclerosis.

Methods and results

Analysis of GTEx database showed that CAD-related SNPs in PHACTR1 are cis-eQTLs for PHACTR1 in arteries. Therefore, we generated Phactr1 knockout mice and crossed them with apolipoprotein E-deficient (ApoE−/−) mice to induce atherosclerosis by high-fat/high-cholesterol (HF-HC) diet. Phactr1 deficiency significantly inhibited atherosclerosis with decreased inflammatory cell infiltration. Western blot showed that PHACTR1 was restricted to endothelial cells (ECs) in mice. Mechanistically, RNAseq of aortic ECs revealed that the major molecular function of PHACTR1 was transcriptional regulation. PPARγ/RXRα was the top transcription factor, and PPARγ target gene expression substantially increased in Phactr1−/− mice. Moreover, we generated endothelial cell specific Phactr1−/−, ApoE−/− mice and found decreased atherosclerotic plaque area in aortic sinus. In vitro, PHACTR1 associated with PPARγ and inhibited PPARγ transcriptional activity. The inhibitory effect of PHACTR1 on PPARγ required its shuttling from cytosol to nucleus triggered by disturbed flow, a well-established pro-atherosclerotic stimulus.

Conclusion

Our results identified PHACTR1 as a mechanosensitive corepressor of PPARγ in ECs to promote atherosclerosis. Endothelial PHACTR1 is a potential therapeutic target for atherosclerosis treatment.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China (NSFC), China Postdoctoral Science Foundation (CPSF)